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475 Cards in this Set
- Front
- Back
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Dermatological Hx should include:
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•Signalment: age, sex, breed, color
•Chief Complaint •Age of Onset •Pruritus, Seasonality, Progression, Travel, Contagion, Response to therapy, Environment •General Medical History |
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Com'n Skin Dz's younger than 6 months
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-Black Hair Follicle dysplasia
-K9 muzzle furunculosis (K9 acne) -Cutaneous asthenia -Demodecosis -Dermatomyositis -Dermatophytosis -Ichthyosis -Impetigo -Juvenile Sterile granulomatous dermatitis and lymphadenitis (juvenile Cellulitis) -Viral papillomatosis |
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Com'n Skin Dz's in 1-3 year old animals
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-Blastomycosis
-K9 Atopic dermatitis -Color dilution alopecia |
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Com'n Skin Dz's in animals older than 6 yo
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-Cushing's
-Sertoli Cell tumor assoc. dysplasia -Superficial necrolytic dermatitis |
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General quality of skin and hair to be noted
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Is the hair dull, dry, brittle, oily, or thin? Is the skin thinned, hyperelastic, or thickened? Are there any pigmentation changes or abnormalities? Are there obvious lesions that will need special attention during closer examination?
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Types of Primary Skin Lesions
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-Macule
-Patch -Papule -Nodule -Pustule -Vesicle -Bulla -Wheal -Plaque -Tumor -Abscess -Cyst |
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Types of Secondary Skin Lesions
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-Epidermal Collarette
-Scar -Callus -Erosion -Ulcer -Fissure -Lichenification (can be seen w/ hyperkeratosis & pigmentation involved) -Sinus -Fistula -Excoriation |
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Types of Primary or Secondary Skin Lesions
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-Alopecia
-Scale -Crust -Follicular casts -Comedo (blackheads) -Hyper/Hypopigmentation |
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Pustules may be:
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Follicular, non-follicular, large w/ multiple follicles (usually immunosuppresive)
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Most com'n sign of Sarcoptic mange
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Alopecia and crusts around the ears
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Terms used to describe lesion configuration
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-Annular
-Single -Multifocal -Polycyclic -Grouped -Sepiginous -Linear -Arciform -Iris (target) |
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Com'n Lesions found on the Head
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-Atopic dermatitis
-Demodicosis -Notoedres -Juvenile sterile granulomatous dermatitis & lymphadenitis |
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Com'n Lesions found on the Ear
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-Atopic dermatitis
-Food intolerance -Fly bite dermatitis -Sarcoptes -Notoedres -Solar dermatitis (feline) |
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Com'n Lesions found on the Eyelid
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Demodecosis
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Com'n Lesions found on the Nasal Planum
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-Discoid lupus erythematosus (collie nose)
-Nasodigital hyperkeratosis -Pemphigus foliaceus -Sterile pyogranuloma syndrome -Uveodermatological syndrome |
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Com'n Lesions found on the Lips
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-Demodicosis
-Indolent ulcer -Intertrigo -Oral papillomatosis |
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Com'n Lesions found in the Oral Cavity (mucosa)
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-Eosinophilic granuloma
-Erythema multiforme -Plasma cell stomatitis -Pemphigus vulgaris -Systemic lupus erythematosus |
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Com'n Lesions found on the Mucocutaneous Junctions
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-Epitheliotropic lymphoma
-Erythema multiforme -Mucocutaneous pyoderma -Superfical necrolytic dermatitis (TEN) |
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Com'n Lesions found on the Chin
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-Demodicosis
-Acne -Dermatophytosis |
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Com'n Lesions found on the Neck
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-Feline atopy
-Flea bite hypersensitivity, feline -Injection site reaction |
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Com'n Lesions found on the Ventral Chest
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-Bacterial folliculitis
-Sternal callus -Contact dermatitis |
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Com'n Lesions found in the Axillary region
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-Acanthosis nigricans
-Atopic Dermatitis -Malassezia dermatitis |
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Com'n Lesions found on the Back
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-Atopic dermatitis
-Bacterial folliculitis -Flea bite hypersensitivity -Schnauzer comedo syndrome -Cheyletiellosis -Seborrhea, primary |
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Com'n Lesions found on the trunk
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-Demodicosis
-Bacterial folliculitis -Hypothyroidism -Hyperadrenocorticism -Sebaceous adenitis |
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Com'n Lesions found on the Abdomen
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-Atopy, feline
-Eosinophilic plaque -Impetigo -Psychogenic alopecia -Solar dermatitis -Contact dermatitis -Atypical mycobacteriosis -Pelodera derematitis |
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Com'n Lesions found on the tail
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-Anal sac dz
-Food intolerance |
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Com'n Lesions found on the Legs
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-Acral lick dermatitis
-Demodicosis |
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Com'n Lesions found on the Paws
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-Sarcoptes
-Demodicosis -Adverse food reaction -Foreign body -Malassezia dermatitis -Pemphigus foliaceus -Plasma cell pododermatitis -Contact dermatitis -Superficial necrolytic dermatitis (NME) |
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Com'n Lesions found on/near the Claws
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-Lupoid onychodystrophy
-Bacterial paronychia -Systemic lupus erythematosus -Pemphigus foliaceus |
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Superficial Skin Scraping
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Performed over large area, collecting abundant material
-Taken from intact, crusted lesions of p's suspected of having Sarcoptes -Elbows, chest, pinna margins com'n areas |
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Terms used to describe lesion configuration
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-Annular
-Single -Multifocal -Polycyclic -Grouped -Sepiginous -Linear -Arciform -Iris (target) |
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Com'n Lesions found on the Head
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-Atopic dermatitis
-Demodicosis -Notoedres -Juvenile sterile granulomatous dermatitis & lymphadenitis |
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Com'n Lesions found on the Ear
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-Atopic dermatitis
-Food intolerance -Fly bite dermatitis -Sarcoptes -Notoedres -Solar dermatitis (feline) |
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Com'n Lesions found on the Eyelid
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Demodecosis
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Com'n Lesions found on the Nasal Planum
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-Discoid lupus erythematosus (collie nose)
-Nasodigital hyperkeratosis -Pemphigus foliaceus -Sterile pyogranuloma syndrome -Uveodermatological syndrome |
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Com'n Lesions found on the Lips
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-Demodicosis
-Indolent ulcer -Intertrigo -Oral papillomatosis |
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Com'n Lesions found in the Oral Cavity (mucosa)
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-Eosinophilic granuloma
-Erythema multiforme -Plasma cell stomatitis -Pemphigus vulgaris -Systemic lupus erythematosus |
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Com'n Lesions found on the Mucocutaneous Junctions
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-Epitheliotropic lymphoma
-Erythema multiforme -Mucocutaneous pyoderma -Superfical necrolytic dermatitis (TEN) |
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Com'n Lesions found on the Chin
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-Demodicosis
-Acne -Dermatophytosis |
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Com'n Lesions found on the Neck
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-Feline atopy
-Flea bite hypersensitivity, feline -Injection site reaction |
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Com'n Lesions found on the Ventral Chest
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-Bacterial folliculitis
-Sternal callus -Contact dermatitis |
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Com'n Lesions found in the Axillary region
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-Acanthosis nigricans
-Atopic Dermatitis -Malassezia dermatitis |
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Com'n Lesions found on the Back
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-Atopic dermatitis
-Bacterial folliculitis -Flea bite hypersensitivity -Schnauzer comedo syndrome -Cheyletiellosis -Seborrhea, primary |
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Com'n Lesions found on the trunk
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-Demodicosis
-Bacterial folliculitis -Hypothyroidism -Hyperadrenocorticism -Sebaceous adenitis |
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Com'n Lesions found on the Abdomen
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-Atopy, feline
-Eosinophilic plaque -Impetigo -Psychogenic alopecia -Solar dermatitis -Contact dermatitis -Atypical mycobacteriosis -Pelodera derematitis |
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Com'n Lesions found on the tail
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-Anal sac dz
-Food intolerance |
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Com'n Lesions found on the Legs
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-Acral lick dermatitis
-Demodicosis |
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Com'n Lesions found on the Paws
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-Sarcoptes
-Demodicosis -Adverse food reaction -Foreign body -Malassezia dermatitis -Pemphigus foliaceus -Plasma cell pododermatitis -Contact dermatitis -Superficial necrolytic dermatitis (NME) |
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Com'n Lesions found on/near the Claws
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-Lupoid onychodystrophy
-Bacterial paronychia -Systemic lupus erythematosus -Pemphigus foliaceus |
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Superficial Skin Scraping
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Performed over large area, collecting abundant material
-Taken from intact, crusted lesions of p's suspected of having Sarcoptes -Elbows, chest, pinna margins com'n areas |
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Dermanyssus gallinae
(Poultry mites) |
May be collected w/ superficial skin scrapings
Tend to be very scarce Scrape near excoriated sites Acetate tape impressions may be used |
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Lynxacarus radovsky
(Feline Fur mite?) |
Attach to hairs over spine
-Rare -Dx via Trichography |
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Deep skin scrapings
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Taken most often when there is a suspicion of demodicosis
-Shar Pei's, particularly deep scrapings needed |
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Pelodera strongyloides
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Free living nematode may invade skin of dogs
-600um larvae seen w/ deep skin scrapings |
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Trichography
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Direct examination of plucked hairs
If ringworm suspected, KOH clearing of keratin may help |
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Trichography especially useful when:
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-Demodex suspected in difficult area to scrape
-Cat fur mites -Pediculosis -Cheyletiellosis -Dermatophytosis |
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Increased number of Hairs in Anagen:
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Suggests an endocrinopathy or follicular arrest
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Skin surface cytology types
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Direct impression
Acetate Tape impression Cotton tipped-swab |
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Acetate tape impression
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Tape pressed against dry skin, mounted on a slide, then stained w/ blue part of diff-Quik stain
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Bacterial culture and susceptibility testing indicated in:
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-Cases responding poorly to appropriate antimicrobial therapy
-Suspected deep Pyoderma -Cases when resistant or uncom'n org's are suspected d/t chronicity or unusual presentations (atypical mycobacteria, Pseudomonas, Nocardia) |
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Abx in regard to C/S
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Should be d/c 48-72 hrs prior to culture
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Deep skin infections best cultured via:
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Best cultured using a skin biopsy, external surface of sample is excised and discarded
-Let lab know that you want it minced and if a special media is needed |
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Dermatophyte Test Media (DTM)
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Contains Abx, an antifungal, and a pH indicator (phenol red- selectively metabolize available proteins before carbs, producing alkali metabolites and turning the media red)
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3 most com'n spp of dermatophytes in SA's
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-#1- Microsporum canis
-Microsporum gypseum -Trichophyton mentagrophytes |
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Wood's Light Examination
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Emits 253.7nm UV light reacting w/ tryprophan metabolites in some spp to emit a yellow-green fluorescence
-Hairs should be exposed for 3-5 minutes |
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Skin biopsy indicated when:
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1) Have lesions suspicious of neoplasia
2) Have lesions consistent w/ a dz which is most readily dx'd by biopsy 3) Display an unusual presentation 4) Have a poor response to therapy 5) Might require long-term and/or expensive therapy |
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TEST TIPS
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-Be able to recognize a M. canis macroconidia
-Trichophyton mentagrophytes are cream-colored colonies, powdery to granular, microconidia usually round, macroconidia cigar shaped, may have spiral shaped hyphae |
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Objectives Lect. 2
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1. Be able to describe and provide examples of resident and transient bacteria of dogs and cats.
2. Describe the therapeutic approach for acute moist dermatitis. 3. Know the factors which may adversely affect the response of a skin infection to antibiotic therapy. 4. Be able to compare acute moist dermatitis with pyotraumatic folliculitis and furunculosis. 5. Understand the causes and therapeutic options for acral lick dermatitis. 6. Describe the typical clinical presentation of feline opportunistic mycobacterial infection. |
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Defense Mechanisms of normal skin
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Physical (hair, s. corneum)
Chemical (sebum, sweat) Microbial (competition for niches, antimicrobial substances) |
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Resident Bact of dogs
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#1- S. intermedius
Clostridium spp Propionibacterium acnes Actinobacter spp Micrococcus spp |
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Transient bact of dogs
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E. coli
Proteus mirabilis Corynebacteria spp Bacillus spp Pseudomonas spp |
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Transient flora of cats
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B-hemolytic strep
E. coli P. mirabilis Pseudomonas spp Bacillus spp |
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Topical Antimicrobials
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Chlorhexidine, providone-iodine (careful w/ cats), ethyl lactate, benzoyl peroxide (best ABx topical tx), Abx
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Most com'n Abx used for skin infxns
*know mech's of axn* |
Cephalexin (80% of time for pyoderma)
Cefpodoxime (simplicef) Amoxicillin-clavulanate Dicloxacillin Clindamycin Enrofloxacin Marbofloxacin Doxycycline Trimethoprim-sulfamethoxazole Rifampin |
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Immunomodulation/Immunostimulation
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Should be given w/ systemic abx tx until pyoderma resolved
Staphage Lysate: S. aureus phage lysate for SC injection. ImmunoRegulin: killed Propionibacterium acnes preparation for IV injection. Autogenous staphylococcal bacterins: not widely used. Levamisole: 2.2 mg/kg q. 48 hrs. Cimetidine: 10 mg/kg TID. IFN-α: human recombinant form has been used at 1-3 million IU/dog po or sc q. 1-3 days. |
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Superficial Bact Infxns
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-Acute moist Dermatitis
-Impetigo -Mucocutaneous pyoderma -Superficial bact folliculitis -Dermatophilosis |
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Deep Bact Infxns
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-Pyotraumatic folliculitis and furunculosis
-Bacterial folliculitis and furunculosis -Nasal folliculitis and furunculosis -Muzzle folliculitis and furunculosis -Interdigital pyoderma -GSD Pyoderma -Acral lick dermatitis & furunculosis -Subcutaneous abscesses -Bact pseudomycetoma -Opportunistic mycobacterial granuloma -Plague -Actinomycosis -Actinobacillosis -Nocardiosis |
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Acute Moist Dermatitis- General info
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-AKA Hot spot, Pyotraumatic dermatitis (PTD)
-Uncom'n in cats |
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Acute Moist Dermatitis- Etiopathogenesis
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-Dvlp in minutes/hours in response to focused self-trauma
-Most often 2ndary to FAD, but many other causes |
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Acute Moist Dermatitis- Therapy
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-Clip/Clean wound
-Non-steroid antipruritic spray (lidocaine, oatmeal) -Topical corticosteroid/Abx spray (gentamycin/betamethasone) -Oral pred -Abx for 14-21 days -E-collar |
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Impetigo- General info
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Puppy pyoderma and bullous impetigo represent 2 subtypes
-NOT contagious -Common |
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Impetigo- Etiopathogenesis (puppy form)
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-Coagulase positive Staph. spp cultured from pustules
-May occur in assoc w/ parasitism, poor nutrition, or poor sanitary condtns, or sporadically in healthy dogs |
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Bullous Impetigo- Etiopathogenesis
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Occurs secondary to immunosuppressive conditions such as Cushing's, hypothyroidism, and diabetes mellitus
-Staph, Pseudomonas may be involved |
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Impetigo- Signalment
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2-12 mos (puppy pyoderma)
Middle age+ (bullous) |
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Impetigo-Clinical presentation
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-Non-follicular pustules in the abdominal and axillary skin
-Usually non-pruritic -Ruptured pustules dvlp into crust and epidermal collarettes |
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Impetigo- Therapy
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-Topical Abx ointment (mupirocin)
-Abx shampoo (chlorhex, benzoyl peroxide products) -Systemic abx if severe |
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Mucocutaneous Pyoderma- general
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AKA- MCP
Uncom'n |
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Mucocutaneous Pyoderma- Etiopathogenesis
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Unknown
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Mucocutaneous Pyoderma- Signalment
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GSD's predisposed, but may occur in any breed/age/sex
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Mucocutaneous Pyoderma- Cx
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-Scale, erythema, and swelling initially
-Lip commisures and wings of nostril most com'nl affected -Lesions progress to painful crusts, exudate, and depigmentation |
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Mucocutaneous Pyoderma- Dx
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Clinical recognition
Skin biopsy Response to therapy |
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Mucocutaneous Pyoderma- Tx
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-Topical abx
-Systemic abx 3-6 wks |
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Superficial Bacterial Folliculitis- general
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AKA Staph folliculitis
Com'n in dogs (short hair > long hair) |
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Superficial bacterial folliculitis- Etiopathogenesis
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-S. intermedius in most cases
-2y to demodicosis, irritant contact derm, atopic derm, FAD |
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Superficial bacterial folliculitis- Signalment
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More com'n in short-haired breeds
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Superficial bacterial folliculitis- Cx
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-Variably pruritic
-Follicular papules, pustules -Elevated tufts resemble hives -Multifocal alopecia |
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Superficial bacterial folliculitis- Dx
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-Clinical recognition of Cx
-R/O demodex and dermatophytosis -Cytology--> PMN's and cocci |
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Superficial bacterial folliculitis- Tx
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-Tx signs or work up underlying condtns
-Abx shampoo 1-2/wk **Systemic abx for min. 3 wks |
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Dermatophilosis- General
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AKA Cutaneous Steptotrichosis
-Very rare in SA's |
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Dermatophilosis- Etiopathogenesis
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Dermatophilus congolensis
-Aerobic, Gram + -Flagellaed, motile zoospores -Does NOT penetrate intact skin -Diplococci "railroad tracts" |
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Dermatophilosis- Cx
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-Papules and coalescing circular crusts
-Crusts are adherent, yellow, incorporate hair -Cats abscess more often |
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Dermatophilosis- Dx, Dogs
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-Crusts minced in water, stained w/ Wright-Giemsa
-Orthokeratotic and Parakeratotic |
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Dermatophilosis- Dx Cats
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Biopsy and histopath of nodule is the method of choice
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Dermatophilosis- Tx, Dogs
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Abx Shampoo and crust removal
-Penicillin V 14-21 days |
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Pyotraumatic folliculitis and furunculosis- General
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-Hot spot
- Pyotraumatic Dermatitis (PTD) |
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Pyotraumatic Folliculitis and Furunculosis- Cx
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-Eroded to ulcerated, alopecic, erythematous, purulent macules
-Pruritis and pain -Com'n on cheek and neck |
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Pyotraumatic Folliculitis and Furunculosis- Dx
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-Cx signs
-Skin biopsy |
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Pyotraumatic Folliculitis and Furunculosis- Tx
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-Same as hot spot tx
-More resistant to tx -Continue Abx 14d past Cx -Discontinue pred ASAP |
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Bacterial Folliculitis and Furunculosis- General
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-AKA Deep folliculitis, furunculosis, cellulitis
-May be assoc. w/ systemic illness -Com'n in dog, rare in cat |
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Bacterial Folliculitis and Furunculosis- Etiopathogenesis
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**S. intermedius most com'n
-Pseudomonas, Proteus, E. coli more com'n in deep than superficial -Secondary to demodecosis, dermatophytosis, immunosuppression |
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Bacterial Folliculitis and Furunculosis- Cx
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Lesions localized or generalized
-papules, pustules, hemorrhagic bullae, sinuses, nodules, etc |
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Bacterial Folliculitis and Furunculosis- Dx
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-By Cx, may be febrile
-Cyto. exam to see bacteria and rule out fungal -Tissue eosinophilia com'n |
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Bacterial Folliculitis and Furunculosis- Tx
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-Severe cases may require IV fluids and parenteral Abx
-Frequent bathing w/ Abx shampoo -Tx 2-3 wks past cure, Often 6-12 wks |
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Nasal Folliculitis and Furunculosis- General
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AKA Nasal pyoderma
*UNCOMMON S. intermedius most com'n |
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Nasal Folliculitis and Furunculosis- Cx
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-Painful papules/pustules on dorsal muzzle
-Rapidly progressive *UNCOMMON |
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Nasal Folliculitis and Furunculosis- Ddx
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-Pemphigus foliaceus, discoid lupus erythematosus, eosinophilic folliculitis and furunculosis, demodecosis, Dermatophytosis
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Nasal Folliculitis and Furunculosis- Tx
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-Abx for 7-14d post-cure
-Soak and clean lesions TID w/ Chlorhex or Burrow's solt'n |
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Muzzle folliculitis and furunculosis- General
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AKA- Canine Acne
*Common* |
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Muzzle Folliculitis and Furunculosis- Etiopathogenesis
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-Probably 2ndry infxn of a sterile process
-Underlying etio may be a genetic keratinization disorder aggravated by local trauma |
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Muzzle Folliculitis and Furunculosis- Signalment
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-Young dogs
-Short-haired breeds |
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Muzzle Folliculitis and Furunculosis- Cx
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-Early papules are sterile follicular papules around the lips and on the chin
-Chronic-- lg bleeding/oozing pustues dvlp |
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Muzzle Folliculitis and Furunculosis- Tx
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-Modify behavior which predispose chin to trauma, if possible
-Mild cases may respond to regular Antibact cleaning/topical Abx -Infected- ORal abx for 4-6wks |
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Interdigital Pyoderma- General
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-AKA pododermatitis, pedal folliculitis/furunculosis
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Bacterial Folliculitis and Furunculosis- General
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-AKA Deep folliculitis, furunculosis, cellulitis
-May be assoc. w/ systemic illness -Com'n in dog, rare in cat |
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Bacterial Folliculitis and Furunculosis- Etiopathogenesis
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**S. intermedius most com'n
-Pseudomonas, Proteus, E. coli more com'n in deep than superficial -Secondary to demodecosis, dermatophytosis, immunosuppression |
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Bacterial Folliculitis and Furunculosis- Cx
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Lesions localized or generalized
-papules, pustules, hemorrhagic bullae, sinuses, nodules, etc |
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Bacterial Folliculitis and Furunculosis- Dx
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-By Cx, may be febrile
-Cyto. exam to see bacteria and rule out fungal -Tissue eosinophilia com'n |
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Bacterial Folliculitis and Furunculosis- Tx
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-Severe cases may require IV fluids and parenteral Abx
-Frequent bathing w/ Abx shampoo -Tx 2-3 wks past cure, Often 6-12 wks |
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Interdigital Pyoderma- Etiology
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-Primary or idiopathic
-S. intermedius most com'n, but G - orgs may be involved and more resistant to Tx -One foot--> FB's (awns), trauma, ostiomyelitis, fungal -Multiple feet--> Hypothyroidism, Demodecosis, Atopy, food allerg., immunodef, hookworms, Pelodera, FB's |
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Interdigital Pyoderma- Dx
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-Rule out underlying causes w/ skin scraping, fungal culture, skin biopsy, FB exploration, Radiography
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Interdigital Pyoderma- Tx
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-Tx w/ syst ABX for 6-8wks or 2 wks past clinical resolution
-Topical Abx/chorhex may help -Chronic cases may me difficult to tx and require debridement, and or fusion podoplasty |
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GSD Pyoderma- General
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-Hereditable dz of GSD's
-Underlying immunodeficiency -Results in inflamm that is out of proportion to the underlying cause |
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GSD Pyoderma- Cx
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-Rump, thighs, back, ventral abd, chest most affected
-Papules, pustules--> crusts, ulcers, fistulae |
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GSD Pyoderma- Tx
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-Tx underlying dz if ID'd
-Clip and clean matted/ulcerated lesions **Systemic ABX for 8-12 wks -ABX shampoo -Chronic ABX Tx may be needed |
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Acral lick Dermatitis and furunculosis- General
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AKA- Lick Granuloma
-Com'n -Chronic lesions carry poor prognosis for resolution |
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Acral lick Dermatitis and furunculosis- Etiology
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-Single lesions = Boredom, local trauma, jt pain
-Multiple lesions = Atopic derm or hypothyroidism -Often 2ndrly infected w/ Stapylococcus/other bact |
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Acral lick Dermatitis and furunculosis- Signalment
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-Lg Breeds
-Middle age to old dogs |
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Acral lick Dermatitis and furunculosis- Tx
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** Long term Tx, 6-12wks ABX
-Behavior modification -Amytriptyline, fluoxetine, CLOMIPRAMINE, variable efficacy -No single modality works in most cases |
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SQ Abscesses- General
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-Frequent in cats, uncom'n in dogs
-WEAR GLOVES!! |
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SQ Abscesses- Etiology
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-Bite wounds (Pasturella multocida)
-Non-healing may result from immunosup, Y. pestis, mycobacterial infxn, Actinomyces, Nocardia spp |
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SQ Abscesses- Dx
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Cx w/ evidence of skin puncture is characteristic
**serology to check FeLV/FIV status** |
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Bacterial pseudomycetoma- General
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-AKA Botryomycosis, cutan. bact. granuloma
UNCOMMON |
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Bacterial pseudomycetoma- Etiology
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-2ndry to penetrating wound most com'n
-Staph most com'n -Pseudomonas, Proteus, Strep, Actinobacillus less com'n |
|
|
Bacterial pseudomycetoma- Cx
|
Single/multiple nodules w/ draining fistulae
|
|
|
Bacterial pseudomycetoma- Dx
|
Skin biopsy
Histopath shows granulomatous to pyogranulomatous inflammation surrounding tissue granules composed of bact and eosinophilic material -Bact C & S |
|
|
Bacterial pseudomycetoma- Tx
|
-Surgical excision
-Systemic ABX |
|
|
Opportunistic Mycobacterial Granuloma- General
|
-AKA= Atypical mycobacterial granuloma
-Uncom'n in cats -Rare in dogs -Guarded prognosis |
|
|
Opportunistic Mycobacterial Granuloma- Etiology
|
-Facultative pathogens found in soil
-Ubiquitous organisms (Mycobact. fortuitum, M. chelonei, M. phlei, M. smegmatis) |
|
|
Opportunistic Mycobacterial Granuloma- Cx
|
-SQ nodules, ulcers, draining tracts and fistulae
-Most com'n location is the inguinal rgn in cats -Dogs--> nodules on pinnae |
|
|
Opportunistic mycobacterial granuloma- Dx
|
-Cx
-Demonstrate acid fast orgs -C & S= alert lab of your suspicion, difficult to grow |
|
|
Opportunistic mycobacterial granuloma- Tx
|
-Surgical excision when practical
-Enrofloxacin, Doxycycline **Months of tx usually necessary (4-6wks past clinical cure) |
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|
Plague- General
|
-Cats/rodents much more susceptible
-30-40 spp of wild rodents as natural reservoirs -Transmitted b/t rodents/fleas -Bubonic, pneumonic, septicemic forms |
|
|
Plague- Etiology
|
-Yersinia pestis
-G Neg, fac anaerob, nonmotile, bipolar staining coccobacillus -Rocky mtn states and Hawaii |
|
|
Opportunistic Mycobacterial Granuloma- General
|
-AKA= Atypical mycobacterial granuloma
-Uncom'n in cats -Rare in dogs -Guarded prognosis |
|
|
Plague- Cx
|
-Febrile (105-106F)
-Dehydration -Submand, retropharyng, cervical LN's abscess and drain (bubo formation) -Bubonic form may progress to septicemic form and pulmonic form (least com'n) |
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|
Plague- Dx
|
-Cytology of exudates and aspirates: monomorphic population of Gram Neg bipolar coccobacilli
|
|
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Plague- Tx
|
Gloves/mask should be worn
-Tx should begin BEFORE laboratory confirmation |
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|
Fungal sections Objectives
|
1. Be able to discuss the three species of dermatophytes which most commonly infect small animals.
2. Describe three clinical presentations of feline dermatophytosis. 3. Describe how to reach a diagnosis of Malassezia dermatitis. 4. Know the geographic distribution of the systemic mycoses. 5. Know which fungal infections carry the greatest risk of zoonosis. |
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Superficial Mycoses
|
-Dermatophytosis
-Malassezia -Candidiasis |
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Dermatophytosis- General
|
-Ringworm
-Overdiagnosed d/t over-reliance of Wood's light examination |
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Dermatophytosis- Etiology
|
-Fungal infxn of the s. corneum, hair, and/or claw by:
-Microsporum, Trichophyton, or Epidermophyton spp. |
|
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Dermatophytosis- 3 most com'n org's
|
Microsporum canis
M. gypseum T. mentagrophytes |
|
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Microsporum canis
|
-Most often acquired from cats
-Spindle-shaped macroconidia w/ thick walls and 6+ cells -White to buff, cottony colony |
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Microsporum gypseum
|
-Most often acquired from soil
-Ellipsoidal macroconidia w/ THIN walls and 4-6 cells -Beige, granular colonies |
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Trichophyton mentagrophytes
|
-Most often acquired from rodents or enviro
-Numerous grape-like clusters of microconidia, few cigar-shaped macroconidia, spiral hyphae -White to cream, powdery to granular colony |
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Dermatophytosis- signamlent
|
-Long haired cats
-Yorkies, dalmatians -Poor nutrition, immunosuppressed at incr risk |
|
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Miliary Dermatitis
|
Characterized by multiple, small, crusted papules and pruritis
-RARELY caused by M. canis, much more com'n from Flea allergies |
|
|
Dermatophytosis- Cx- Dogs
|
-Annular lesions w/ alopecia, follicular papules, scale and crust most com'n
-Folliculitis, furunculosis and scarring alopecia seen w/ T. mentagrophytes |
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Kerion
|
Nodule w/ purulent exudate
|
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Dermatophytosis- Dx
|
-DTM
-Wood's Light -Trichography (ectothrix spores) -Skin biopsy (not as sensitive as DTM) |
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Dermatophytosis- Tx
|
-Isolation
-Environmental deconamination -spores viable for 18mos -1:10 or 1:20 bleach -Destroy Bedding/grooming aids -Topical-- CLOTRIMAZOLE, miconazole, terbinafine -Shampoos--chlorhex, miconazole -Rinses-- Lime sulfur -Systemic- Griseofulvin -Microsized (Fulvicin U/F) -Ultramicrosixed (Gris-PEG) Fluconazole Itraconazole Ketoconazole |
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Malassezia Dermatitis- General
|
-Yeast dermatitis
-Com'n in dogs, rare in cats |
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Malassezia Dermatitis- Etiology
|
M. pachydermatis (syn Pityrosporum canis)is a normal inhabitant of K9 skin/ears
-Other factors may predispose to overgrowth, various dermatites, FAD, etc |
|
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Malassezia Dermatitis- Cx
|
-Pruritis
-Generalized or regional -Lichenification and hyperpigmentation if chronic -Paronychia and claw infxns w/ brown discoloration and waxy accum on claws and nail biting |
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Malassezia Dermatitis- Dx
|
Skin surface cytology
-Direct impression -Acetate tape impression -Cotton-tipped swab Skin biopsy less sensitive b/c outer half of s. corneum lost during processing |
|
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Malassezia Dermatitis- Topical Tx
|
Ointments: Clotrimazole, miconazole, terbinafine
Shampoos and rinses: Chlorhex, miconazole |
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Malassezia Dermatitis- Systemic Tx
|
Ketoconazole
Itraconazole, fluconazole ***Griseofulvin is NOT effective*** |
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Candidiasis- General
|
AKA- Moniliasis, Thrush
-RARE -Normal inhabitants of alimentary, upper resp, genital mucosa |
|
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Candidiasis- Signalment
|
-Dogs w/ Diabetes mellitus, Cushing's, Hypothyroidism, neoplasia, taking immunosuppressive drugs
|
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Candidiasis- Cx
|
-Grey plaques/ulcers in mucocutaneous jxns, ear canal, intertriginous areas, interdigital areas
-Papular to pustular lesions |
|
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Candidiasis- Dx
|
-Cutaneous cytology
-Narrow-based budding org's |
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Candidiasis- Tx
|
-Correct underlying dz
-Control moisture by clipping and cleaning, when approp. -Topical antifungals -Systemic antifungals -Ketoconazole -Itraconazole |
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Subcutaneous Mycoses
|
-Often introduced via trauma, grow in living tissue
-Eumycotic mycetoma -Phaeohyphomycosis -Zygomycosis -Sporotrichosis -Rhinosporidiosis |
|
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Eumycotic mycetoma- General
|
-Maduromycosis
-Tropical dz -Rare in US |
|
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Eumycotic mycetoma- Etiology
|
-Most com'nly caused by Pseudoallescheria boydii
-Gains entry via wound contamination |
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Eumycotic mycetoma- Cx
|
-Solitary nodules, draining tracts and tissue grains
-Head/limbs most affected |
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Eumycotic mycetoma- Dx
|
Cytology
Histopathology Fungal culture |
|
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Eumycotic mycetoma- Tx
|
-Surgical excision or limb amputation
-Poor prognosis |
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Phaeohyphomycosis- General
|
-AKA Chromomycosis
-Pigmented hyphae -RARE to UNCOMMON |
|
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Phaeohyphomycosis- Etiology
|
-Many dematiaceous soil saprophytes are capable of causing this
-Bipolaris spiciferum -Xylohypha bantiana |
|
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Phaeohyphomycosis- Dx
|
Cytology and histopath
-Granulomatous to pyogranulomatous dermatitis and panniculitis |
|
|
Phaeohyphomycosis- Tx
|
-Poor prognosis w/ recurrence com'n
-Ketoconazole -Itraconazole -Flucytosine -Amphotercin B -Wide surgical excision |
|
|
Zygomycosis- General
|
-Mucormycosis, entomopthoromycosis
|
|
|
Zygomycosis- Etiology
|
-RARE in dogs & cats
-Multiple fungi cause this -Rhizopus, Mucor, Absidia, Conidiobolus, Basidiobolus |
|
|
Zygomycosis- Cx
|
-Solitary or multiple ulcerated, draining nodules on extremities
|
|
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Zygomycosis- Tx
|
-Surgical excision or debulking along w/ antifungal therapy
|
|
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Sporotrichosis- General
|
-UNCOMMON
-Zoonotic -Exudates and tissues from cats are infective |
|
|
Sporotrichosis- Etiology
|
-Sporothrix schenckii
-Mycelial form in environment, yeast form in tissue -Gains entry via wound -Dogs- splinters and thorns -Cats- Contaminated claws |
|
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Sporotrichosis- Cx
|
-Cutaneous, cutaneolymphatic, disseminated froms may occur concurrently
-Lesions begin distally and travel up -Cats dvlp abscesses and cellulitis under puncture wound -Dissemination often evident at necropsy |
|
|
Sporotrichosis- Dx
|
**Suspect this dz when an abscess or wound responds poorly to tx**
-Fluorescent Ab testing |
|
|
Sporotrichosis- Tx- Dogs
|
-Supersaturated solution of potassium iodide (SSKI) is the tx of choice
-If iodism is a concern, use ketoconazole or itraconazole |
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Sporotrichosis- Tx- Cats
|
Itraconazole is Tx of choice since cats are more susceptible to SSKI and Ketoconazole SE's
-Monitor for hepatotoxicity, anorexia, vomiting, wt. loss |
|
|
Rhinosporidiosis- General
|
RARE in dogs
NOT reported in cats |
|
|
Rhinosporidiosis- Etiology
|
Rhinosporidium seeberi
Difficult to culture Mucous Mb trauma may predispose to infxn |
|
|
Rhinosporidiosis- Tx
|
Surgicl excision of polyps is often curative
-Dapsone or Ketoconazole may help w/ recurrence |
|
|
Systemic Mycoses (Cutaneous manifestations)
|
-Blastomycosis
-Coccidiomycosis -Cryptococcosis -Histoplasmosis Hematogenous and lymphatic spread of deep or systemic mycoses may lead to skin infxn Primary cutaneous infxn is extremely rare |
|
|
Blastomycosis- General
|
UNCOMMON in dogs
VERY RARE in cats -MS, OH, MO river valleys -NOT zoonotic by aerosol from infected pets, but humans have gotten infected at the same time as pets |
|
|
Blastomycosis- Etiology
|
Blastomyces dermatitidis, a dimorphic saprophyte
-Inhalation of spores from mycelial growth in enviro **Infection established in the lungs** |
|
|
Blastomycosis- Signalment
|
1-5 yo, male, outdoor, hunting dogs most com'nly affected
|
|
|
Blastomycosis- Cx
|
-Skin lesions in 20-40% of infected dogs
-Planum nasale, face, and nail beds most com'n sites -Papules, plaques, nodules, ulcers, draining tracts, abscesses -Multi-system involvement: fever, dry harsh lung sounds, ocular lesions, lameness and bone involvement, wt loss |
|
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Blastomycosis- Dx
|
-Cytology of exudates shows round to oval yeast
-Histopath -Fungal culture -Serology -Radiograph chest, and lame limbs |
|
|
Blastomycosis- Tx
|
-Itraconazole Tx of choice**
-Amphotericin B and Ketoconazole alternatives -Fair prognosis if no brain involvement or bad lung dz |
|
|
Coccidiodomycosis- General
|
-San Joaquin Valley Fever
-Valley Fever -UNCOM'N (dogs) to RARE (cats) -Southwestern US |
|
|
Coccidiodomycosis- Etiology
|
Coccidiodes immitis, a soil-borne fungus
-Epidemics may follow wind, recent rain, or earthquakes -Inhalation of arthroconidia -Most asymptomatic |
|
|
Coccidiodomycosis- Signalment
|
1-4 yo male dogs predisposed
|
|
|
Coccidiodomycosis- Cx
|
-Multi-system involvement:
fever, anorexia, wt. loss, depression -Skin lesions 2ndry to disseminated dz **Papules, nodules, ulcers and draining tracts usually over site of infxn in DISTAL long bone** |
|
|
Coccidiodomycosis- Dx
|
Cytology and histology may work, but not com'nly
-Dx based on clinical signs, radiograph findings, and serology -Fungal culture should be avoided |
|
|
Coccidiodomycosis- Tx
|
Guarded prognosis w/ frequent relapses
-Ketoconazole, itraconazole, fluconazole, Amphotericin B |
|
|
Cryptococcosis- General
|
-RARE in dogs
-UNCOMMON in cats **Pigeon droppings serve as the main reservoir** -NOT Zoonotic |
|
|
Cryptococcosis- Etiology
|
Cryptococcus neoformans is a ubiquitous, saprophytic, round, yeast-like fungus
-Forms a capsule when growing in tissue, hindering Ag presentation -Rte of infxn--Inhalation |
|
|
Cryptococcosis- Signalment
|
-Siamese cats susceptible
-In dogs, young adults -Doberman, Great Danes, American Cockers |
|
|
Cryptococcosis- Cx
|
-Skin lesions in 40% of cats, 20% of dogs
-Nasal cavity involved in 80% of cats (polyps) -Papules, nodules, ulcers, draining tracts -Other signs: CNS, ocular, wt loss, mild fever |
|
|
Cryptococcosis- Dx
|
-Cytology of nasal exudates, skin exudates, CSF, tissue impressions
-Fungal culture, histopath, serology |
|
|
Cryptococcosis- Tx
|
-Long term tx - 7-10 mos
-Serial latex agglutination testing help to monitor response -ITRACONAZOLE drug of choice -Fluconazole for CNS involvement -Ketoconazole- Use w/ CAUTION w/ cats -Amphotericin B and Flucytosine used less com'nly d/t toxicity |
|
|
Histoplasmosis- Etiology
|
Histoplasma capsulatum
-Survives best in soils w/ bat and bird excrement -Inhalation probable route of inoculation |
|
|
Histoplasmosis- General
|
UNCOMMON in dogs/cats
-Most cases in MI, MO, OH River valleys |
|
|
Histoplasmosis- Signalment
|
-Young cats and dogs (<4yo)
-Pointers, Weim's, Brittany spaniels |
|
|
Histoplasmosis- Cx
|
-Disseminated dz most com'n
-Skin infrequently affected -Papules, nodules, ulcers, tracts -Usually multiple lesions -Face, nose, pinnae -Depression, wt loss, anorexia, dyspnea -Dogs--> Lg bowel diarrhea |
|
|
Histoplasmosis- Dx
|
-Org's usually numerous in exudates and tissues
-Intracellular small, round yeast in mononuclear cells -Basophilic center and light halo caused by shrinkage -Fungal culture should be avoided (let the pro's do it) -Serology unreliable |
|
|
Histoplasmosis- Tx
|
-Itraconazole
-Fluconazole (CNS) -Ketoconazole less effective |
|
|
Parasitic Skin Diseases I: Mites, Helminths, & Flies
Objectives: |
1. Be able to describe the clinical features, diagnosis, and treatment of canine demodicosis.
2. Be able to recognize the mites affecting dogs and cats. 3. Understand why ivermectin is more toxic to certain individuals. 4. List three techniques for the collection of Cheyletiella mites. |
|
|
Demodicosis- General
|
AKA-Follicular mange, Red mange
-Com'n in dogs -RARE in cats |
|
|
Demodicosis- Etiology in Dogs
|
-Demodex canis
-Normal resident of skin -Juvenile onset assoc. w/ immune abnormalities and genetics -Adult onset assoc. w/ Immuosuppression, metabolic dz, neoplasia |
|
|
Demodicosis- Etiology in Cats
|
Demodex cati assoc'd w/ systemic dz (FIV, FeLV, diabetes mellitus, SLE)
-Plumper mite -CONTAGIOUS |
|
|
Localized Demodicosis
|
-5 or less discrete lesions
-Periocular, perioral, limbs most com'nly affected -Mild erythema, alopecia -Non-pruritic |
|
|
Generalized Demodicosis
|
>5 patches, lg rgns, or generalized
-Any rgn of the body, esp feet -Mild-severe erythema, alopecia -Swelling, sinus tracts may dvlp -May dvlp deep bact folliculitis/furunculosis -Greasy and malodorous |
|
|
Felin Demodicosis
|
-Periocular, head, neck alopecia
-Erythema, scale, crust -Ceruminous otitis externa -Pruritis variable, severe w/ D. gatoi |
|
|
Demodicosis- Tx- dogs
|
-Localized, should resolve w/o tx
-Topical benzoyl peroxide gel or rotenone -Repeat monthly skin scapings until 2 negatives -Amitraz (Mitaban)- *ONLY approved tx -Don't bathe b/t dips -Ivermectin -Milbemcyin (Interceptor) |
|
|
Demodicosis- Tx- cats
|
-Often self-limiting
-Weekly lime-sulfur dips for 4 wks if generalized or D. gatoi |
|
|
Canine Scabies- Etiology
|
-S. scabiei var. canis
-Front legs short w/ UNJOINTED pedicles and suckers -Burrow in the s. corneum |
|
|
Canine Scabies- Cx
|
-Pruritis severy by 3-4wks
-Positive pinnal-pedal reflex -Ventral chest, abdomen, legs, elbows, pinnal margins -Papules, alopecia and erythematous, excoriated crusted macules |
|
|
Canine Scabies- Dx
|
-Superficial skin scrapings positive less than 50% of time
-When scabies suspected, but not seen, trial tx w/ Revolution -Skin scrapings over large areas |
|
|
Canine Scabies- Tx
|
-Isolation
**Tx ALL dogs in house** -Selamectin (Revolution) every 2 wks for 3-4 tx's -Ivermectin SQ wkly for 3-4wks -Milbemycin -Lime-sulfur dips -In many cases the pruritis will worsen at first, by 14d improvement should be seen |
|
|
Notoedric Mange- General
|
-AKA Feline scabies, Head mange
-HIGHLY contagious -ZOONOTIC |
|
|
Notoedric Mange- Etiology
|
-Notoedres cati (a sarcoptiform mite)
-Smaller than sarcoptes, look similar, w/ dorsal anus |
|
|
Notoedric Mange- Cx
|
-Pinnae, face, neck, legs, feet, perineum mostly affected
|
|
|
Notoedric Mange- Dx
|
Skin scrapings reveal mites w/ UNJOINTED pedicles (shorter than sarcoptes) w/ suckers
|
|
|
Notoedric Mange- Tx
|
Selamectin
Ivermectin a good alternative |
|
|
Cheyletiellosis- General
|
"Walking Dandruff"
-Dogs, cats, rabbits -Zoonotic |
|
|
Cheyletiellosis- Etiology
|
Dogs- C. yasguri
Cats- C. blakei Rabbits- C. parasitivorax |
|
|
Cheyletiellosis- Cx
|
-Pruritis varies from non-existent to severe
-Dorsal distribution of scaling -May be asymptomatic |
|
|
Cheyletiellosis- Dx
|
-Acetate tape impression
-Superficial skin scraping -Fecal exam -Visualization |
|
|
Cheyletiellosis- Tx
|
-Selamectin once monthly
-Ivermectin every 2wks -Milbemycin weekly (9X) -Lime Sulfur dips wkly |
|
|
Trombiculosis- General
|
-Chiggers, Harvest mites
-Most of time spent off patient -Summer/Fall |
|
|
Trombiculosis- Etiology
|
-Eutrombicula alfreddugesi
-Neotrombicula autumnalis -Walchia americana Larvae feed on animals |
|
|
Trombiculosis- Cx
|
-Lesions in areas w/ contact to ground: feet, head, ears, ventrum
-Intensely pruritic |
|
|
Trombiculosis- Dx
|
Visualization
|
|
|
Trombiculosis- Tx
|
Fipronil spray
|
|
|
Dermanyssus gallinae- General
|
-Poultry mite, red mite
-Rarely affects dogs and cats -May affect pets w/ access to poultry |
|
|
Dermanyssus gallinae- Tx
|
-Pyrethrin shampoo
-Revolution likely as effective -Environmental decontamination |
|
|
Lynxacarus radovsky- General
|
-Cat fur mite
-AUS, HI, Brazil -Not very contagious |
|
|
Lynxacarus radovsky- Tx
|
-Fipronil
-Ivermectin -Lime sulfur dips |
|
|
Otodectes cynotis- General
|
-Ear mite
-Non-burrowing mite -3wk life cycle Highly contagious |
|
|
Otodectes cynotis- Tx
|
-Selamectin
-Fipronil -Ivermectin -Otic preparations |
|
|
Pelodera- General
|
-Rhabditic dermatitis
-Uncom'n in dogs |
|
|
Pelodera- Etiology
|
-Pelodera strongyloides
-Aberrant infestation w/ larval stage of a free-living nematode found in organic material (Straw) |
|
|
Pelodera- Cx
|
-Pruritis of the ventral chest and abdomen, feet, legs
-Erythematous and alopecic skin dvlping papules, pustules |
|
|
Pelodera- Dx
|
-Skin Scrapings
-Skin biopsy |
|
|
Pelodera- Tx
|
-Remove infected bedding
-Tx environment w/ insecticide -Self-limiting when bedding replaced |
|
|
Hookworm Dermatitis- General
|
-Uncom'n in dogs, rare in cats
-Spring/Summer most com'n |
|
|
Hookworm Dermatitis- Etiology
|
Uncinaria stenocephala most com'n
-3rd stage larvae enter skin |
|
|
Fly Bite Dermatitis- Etiology
|
-Stomoxys calcitrans (stable fly)
-Simulidae spp (black flies) |
|
|
Fly Bite Dermatitis- Cx
|
-Highest pt of ears most com'nly bit by stable flies
-Hairless/thin areas bitten by black flies |
|
|
Fly Bite Dermatitis- Tx
|
Fly control measures
-Repellants (permethrin, citronella) -Clean enviro -Topical Abx/steroids |
|
|
Hymenoptera
|
-Bees, wasps, hornets
-Eosinophilic folliculitis and furunculosis of the face |
|
|
Fire Ants
|
Solenopsis invicta
-1-2 cm wheals |
|
|
Fleas vectors for:
|
Transmit Rickettsia, Bartonella, Dipylidium
|
|
|
Echidnophaga gallinacea
|
Poultry sticktight flea
|
|
|
Spilopsyllus cuniculi
|
Rabbit flea
|
|
|
Flea Bite Hypersensitivity- General
|
Type I Hypersensitivity rxn
Cutaneous basophil hypersensitivity |
|
|
Flea control- Adulticides
|
-Fipronil (Top spot, frontline Plus)
-Imidacloprid (Advantage) -Selamectin (Revolution) -Nitenpyram (Capstar) --other traditional insecticides |
|
|
Fipronil
|
-Blocks GABA-gated Cl channel in insects
|
|
|
Imidacloprid
|
-Blocks nicotinic receptors of postsynaptic neurons
|
|
|
Selamectin
|
-Semisynthetic avermectin
-GABA interaxn, increases Cl permeability |
|
|
Nitenpyram
|
-Neonicotinoid
-Binds nicotin receptors |
|
|
Insect Growth Regulators
|
-Lufenuron (Program)
-Methoprene (Frontline Plus) |
|
|
Fleas- Antipruritic therapy
|
Dogs
-Dexamethasone -Prednisone -Trimepramine/Pred (Temaril-P) Cats -Methylprednisone -Prednisolone -Antihistamines |
|
|
Pediculosis- General
|
-Lice infestation
-Dorsoventrally flattened -Entire life on host -Nits on hair shaft -14-21 d life cycle -May be more com'n during winter |
|
|
Sucking Lice
|
Anoplura
-Linognathus setosus (dogs) |
|
|
Biting lice
|
Mallophaga
-Trichodectes canis -Felicola subrostrata -Heterodoxus spiniger (dogs) |
|
|
Ticks- Common species
|
-Rhipicephalus sanguineous (brown dog tick)
-Dermacenter variabilis (American dog tick- rectangular basis capituli) -Ixodes Pacificus (Western black-legged tick) |
|
|
Ticks- Tx
|
-Tick removal, soak w/ alcohol and apply steady traction
-Amitraz collars (Preventic) -Fipronil -Methoprene, permethrin (dogs) -Selamectin -Premise tx w/ chlorpyrifos |
|
|
Atopic Dermatitis- Objectives
|
1. Be able to describe the difference between extrinsic atopic dermatitis and intrinsic atopic dermatitis.
2. Learn some of the breeds that are predisposed to atopic dermatitis. 3. Be able to describe how you would make a diagnosis of atopic dermatitis. 4. Understand the limitations intradermal testing, serum allergy testing, and immunotherapy. 5. Be able to describe how you would manage a dog with mild, seasonal atopic dermatitis versus one with severe, year-around atopic dermatitis. 6. Know the indications and potential side effects of cyclosporine A therapy. |
|
|
Atopic Dermatitis- General
|
AKA- Allergic inhalant dermatitis, airborne allergies
-Dogs > Cats -3-15% of all dogs -Predisposed to become allergic to normally innocuous substances |
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Atopic Dermatitis- Etiology
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-Immunologic response not well understood
-Type I HS rxn -Animal becomes sensitized to allergen-specific IgE, which binds to receptor sites on cutaneous mast cells, further allergen exposure causes mast cell degranulation (d/t IgE x-linking)and results in release of histamine, tryptase, chymase, leukotrienes, TNF-a |
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Atopic Dermatitis- Pathogenesis may also include:
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-Epidermal lipid barrier defect allowing percutaneous absorption of allergens at sites of friction and trauma
-Allergen processed by Langerhans cells and presented to allergen-specific T-cells -Sub-class of IgE which is overabundant in atopic dogs -Increased inflamm mediators -Failure to down-regulate |
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Atopic Dermatitis- Signalment
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-Familial history is com'n, although unclear how
-Any breed affected -Shar pei, WHWT -Onset 1-3yrs |
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Atopic Dermatitis- Dx
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-Mild to severe pruritis
-Primary lesions may occur, but 2ndry more com'n -Chronicity leads to salivary staining, hyperpigmentation, lichenification |
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Atopic Dermatitis- Com'n areas affected
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-Interdigital spaces
-Carpal/tarsal areas -Muzzle -Periocular rgns -Axillae -Groin -Pinnae |
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Atopic Dermatitis- Dx
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-A clinical Dx b/c lab testing isn't very specific or sensitive
-Seasonal pruritis -Exclusion of FA w/ approp elimination trial -Exlusion of FBH w/ flea ctrl -Typical distribution -Recurrent otitis externa |
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Atopic Dermatitis- Allergy Testing
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-Should be used to select allergens for inclusion in immunotherapy tx, not for a dx
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Drugs to withdraw prior to intradermal allergy testing
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Antihistamines- 14d
Topical steroids- 14-21d Prednisone- 4 wks Inj. Triamcinolone- 6wks |
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Sedation to avoid prior to Intradermal Allergy testing
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-Oxymorphone, ketamine/diazepam, acepromazine, propofol
-OTHER sedatives should be ok |
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Intradermal Testing (IDT) methods and results
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-Inject histamine and saline for +/- controls
-Inject 0.05-0.1cc of each sol'n intradermally -Wheal sized 0-4 -0-1 negative -Test rxns evaluated 15mins after injxn |
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Serological allergen-specific IgE testing (SAT)
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Does not agree well w/ IDT
-Repeatability varies |
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Serological allergen-specific IgE testing (SAT)--Advantages over IDT
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-Sedation not required
-Less invasive -Less concerns about drug withdrawal |
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Serological allergen-specific IgE testing (SAT)-- Disadvantages over IDT
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-Results not immediate
- Immunotherapy less effective based on SAT results -No control over allergen selection |
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Atopic Dermatitis- Tx- General
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-Tx usually required for life, at least seasonally
-Tailor Tx's to signs -Combo therapy -Tx pyoderma or Malassezia |
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Atopic Dermatitis- Tx- Topical
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-Fluocinonide spray (Genesis)
-Antipruritc shampoos (oatmeal, hydrocort.) |
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Atopic Dermatitis- Essential FA supplementation
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-Best used as an adjunctive therapy
-Total dietary EFA supplementation is more significant than adding sm amts |
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Atopic Dermatitis- Tx- Antihistamines
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-Evidence supporting efficacy is poor (10-20% of time)
-Hydroxyzine -Diphenhydramine -Clemastine -Chlorpheniramine -Loratadine |
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Atopic Dermatitis- Tx- Glucocorticoids
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-In spite of SE's, efficacy and low cost are important
-Use the least amt to control pruritis -Break itch-scratch cycle -Trimeprazine/prednisolone (Temaril-P) -Pred, Prednis, Methylprednisolone EOD -INJECTABLE: Dexamethasone (short acting) vs Methylprednisolone (long term) |
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Atopic Dermatitis- Cyclosporine A (Atopica)
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-Lipophilic cyclic fungal polypeptide
-Microemulsion concentrate -Low cytotoxicity vs immunosuppression -Block CK gene transcription in activated T-cells -Inhibits fxns of cells which initiate immune response (lymphocytes,etc) -Inhibits fxns of effector cells (mast cells, eosinophils) |
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Atopic Dermatitis- Atopica SE's
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Vomiting, Soft stool, diarrhea, hirsutism, gingival hyperplasia, Cutaneous papillomatosis
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Atopic Dermatitis- Atopica drug interactions
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-Metabolized by cytochrome P-450
-Inhibitors may increase CsA levels -Ketoconazole -Cimetidine? -Methylprednisolone -Doxycycline |
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Atopic Dermatitis- Miscellaneous Non-steroidal drugs
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-Amitriptyline
-Doxepin -Misoprostol -Pentoxifylline |
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Atopic Dermatitis- Tx- Immunotherapy
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~70-80% efficacy (at least 50%)
-Response is slow and gradual -Gradually incr amts of allergens |
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Adverse Food Reactions, Contact Dermatitis, and Eosinophilic Granuloma Complex-- Objectives
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1. Know the clinical presentation of adverse food reactions in dogs and cats.
2. Understand how to go about diagnosing an adverse food reaction. 3. Be able to describe the pathogenesis of allergic contact dermatitis. 4. Describe the clinical presentations comprising the eosinophilic granuloma complex of cats. |
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Adverse Food Rxns- General
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-Food hypersensitivity and food intolerance
-UNCOMMON -5-15% allergic skin dz in dog/cat |
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Adverse Food Rxns- Etiology
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-Not completely understood
-Immediate (Type I HS) or delayed (Types III & IV) -Non-immunologic, involves effect of ingredients of food inducing histamine release |
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Adverse Food Rxns- Cx
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-Non-seasonal pruritis
-Poorly glucocorticoid responsive -Distribution is identical to Atopy -Dz may be limited to ears |
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Adverse Food Rxns- Dx
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-Neither IDT or SAT are reliable for diagnosing AFR
-Hypoallergenic diet trials w/ provacative challenge testing is most reliable method of dx -Switch diet for 6-12wks |
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Contact Dermatitis- General
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2 types
-Allergic contact dermatitis (ACD) -Irritant contact dermatitis (ICD) |
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Adverse Food Rxns- Etiology
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ICD
-Direct damage to keratinocytes by exposure to a chemical ACD -Immunologic rxn involving Type IV HS -Elicitation phase occurs on subsequent exposure, Memory T-cells recruited to the area, host of CK's released w/ the end result of inflamm |
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Adverse Food Rxns- Tx
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Avoidance
Prednisone Pentoxifylline |
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Eosinophilic Granuloma Complex- General
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3 distinct entities in the cat:
1) Eosinophilic granuloma (linear) 2) Eosinophilic plaque 3) Indolent ulcer (lip ulcer) COMMON in cats RARE in dogs |
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Eosinophilic Granuloma Complex- Signalment
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-Indolent ulcers more frequent in females
-Eosinophilic plaques- geneteic |
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Eosinophilic Granuloma Complex- Cx- Eosinophilic plaque
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-Pruritic, alopecic, erythematous, eroded patches and plaques
-Ventral abdomen and axillae |
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Eosinophilic Granuloma Complex- Cx- Eosinophilic granuloma
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-White to yellow plaques, nodules
-Linear lesions on cd thighs, swelling of chin, oral nodules |
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Eosinophilic Granuloma Complex- Cx- Indolent ulcers
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-Non-painful ulcers on the upper lip, usually adjacent to philtrum
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Eosinophilic Granuloma Complex- Tx
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-Methylprednisolone
-Prednisolone -Immunotherapy or hypoallergenic diets may be successful in those cases where a specific dx is made |
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Immune Mediated Skin Dz's- Objectives
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1. Be able to compare and contrast the various forms of pemphigus/pemphigoid diseases.
2. Know the non-cutaneous signs of systemic lupus erythematosus. 3. Know the clinical presentations of EM and TEN. 4. Be able to describe how you would make a specific diagnosis and treat a patient with nasal depigmentation and/or crusting. |
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Immune Mediated Skin Dz's- General
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AI dz's result from dvlpmt of Ab's or lymphocytes directed against normal body tissues
-Secondary IM dz's are those resulting from rxns to foreign substances that stim. immunologic rxns -1-2% of all k9, feline dermatoses |
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Immune Mediated Skin Dz's- Hypothetical mechanisms
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-Suppressor T-cell dysfxn
-X-reacting Ag's -Abnormal MHC II expression or interaxn |
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Pemphigus foliaceus- General
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AKA- PF
Most com'n form of pemphigus complex |
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Pemphigus foliaceus- Etiology
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-Primary target Ag is desmoglein I, an adhesion molecule of keratinocytes
-Auto-Ab's against desmoglein I result in loss of adhesiveness -Subcorneal pustules containing rounded keratinocytes (ACANTHOCYTES) dvlp -Drug-induced form should be self-limiting |
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Pemphigus foliaceus- Signalment
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Akita, Chows, Labs, Dobies, others
Mean age of onset- 4 years |
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Pemphigus foliaceus- Cx
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-Planum nasale, face, ears most com'nly affected in dogs
-Footpads, nail beds, areolas, most com'n in cats -Depigmentation, crusting, erythema com'nly observed -Pustules, erythema, alopecia -Variable pruritis |
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Pemphigus foliaceus- Dx
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-Cytology of pustules: PMN's and acantholytic keratinocytes
-Histopath- Subcorneal pustular dermatitis w/ acantholysis and acanthlytic keratinocytes in pustules, crusts -Immunohistochem- Intracell Ab deposition in the s. spinosum |
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Pemphigus foliaceus- Tx
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-#1-Prednisolone or Pred
-Triamcinolone, methylprednisolone -Azothioprine (not in cats- BM suppression) -Chorambucil (Leukeran) LT mgmt -Chrysotherapy (gold salts) -Aurothioglucose, Auranofin |
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Pemphigus erythematosus- General
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-Poss mild form of PF
-Face and ears MOST com'nly affected -Depigmentation on planum nasal early in dz -May worsen w/ SUN xpsure |
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Pemphigus erythematosus- Cx
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-Histopath features of both PF and DLE
-Subcorneal pustules w/ acanthocytes, acantholysis, Lymphocytic-plasmacytic interface dermatitis |
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Pemphigus erythematosus- Tx
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-Sun avoidance
-Topical glucocorticoids -Topical tacrolimus (Protopic) -Tetracycline and niacinamide -Oral pred |
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Pemphigus Vulgaris- General
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RARE in dogs/cats
-Target Ag is desmoglein III, an adhesion molecule |
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Pemphigus Vulgaris- Cx
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-Vesicles, bullae, ulcers of oral cavity/mucocutaneous jxns, groin, axillae
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Pemphigus Vulgaris- Dx
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-Histopath: SUPRAbasilar acantholysis, clefts, and basement mb attached basal cells appearing as "ROW OF TOMBSTONES" (deeper than PF)
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Pemphigus Vulgaris- Tx
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-Early and aggressive Tx warranted
-Pred and azathioprine (dogs) -Poor prognosis |
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Pemphigus vegetans- General
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EXTREMELY RARE DZ OF DOGS*
-May represent a variant of PF -Tx same as PF |
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Pemphigus vegetans- Cx
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-Vesicles and pustules on verrucuous vegetations
-Variable pruritis |
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Bullous Pemphigoid- General
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-VERY RARE in dogs/cats
-Collagen type XVII is hemidesmosome Ag apparently involved |
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Bullous Pemphigoid- Cx
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-Vesicles, bullae, ulcers
-Looks like PF -Vesicles tense and persistent -2ndry pyoderma com'n -Axillae and groin most affected |
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Bullous Pemphigoid- Dx
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-Excisional biopsy of vesicle
-Histopath: Subepidermal cleft and vesicle formation -DIF or IH testing reveals linear deposition of Ig's and C' at Basement mb |
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Bullous Pemphigoid- Tx
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-Aggressive immunosuppressive Tx usually required
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Discoid Lupus Erythematous- General
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-AKA- DLE, Collie nose
-Com'n in dogs -VERY RARE in cats |
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Discoid Lupus Erythematous- Etiology
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-Aggravated by sunlight ~50% of cases
-Type III HS rxn -Auto-Ab's to nuclear Ag's or immune complex deposition involved in lesion formation |
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Discoid Lupus Erythematous- Signalment
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Collies, Shelties, GSD's
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Discoid Lupus Erythematous- Cx
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-Depigmentation and erosions early in the course of dz
-Crusting ulcerations may dvlp -Nasal planum, nares, lips, dorsal muzzle |
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Discoid Lupus Erythematous- Dx
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-Histopathology samples should be taken from depigmented, but non-ulcerated areas
-ANA (anti-nuclear Ab) testing is usually NEGATIVE |
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Discoid Lupus Erythematous- Tx
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-Sun avoidance
-Tailor to severity -Topical glucorticoids -Topical tacrolimus -Vit. E -Tetracycline and niacinamide -Pred |
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Vesicular cutaneous lupus erythematosus- General
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-Rough collies and Shelties
-Onset usually during summer |
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Vesicular cutaneous lupus erythematosus- Cx
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-Annular and polycyclic ulcerations on the ventral abdomen, axillae, groin, pinnae
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Systemic Lupus Erythematosus- General
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-AKA- SLE
*A multisystem AI dz of unknown etiology -UNCOMMON in dogs -RARE in cats |
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Systemic Lupus Erythematosus- Etiology
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-Antinuclear and anticytoplasmic Ab's are formed
-Immune complexes deposited in glomerular basement mb, synovial mb, skin, BV's -C'activation results in tissue injury |
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Systemic Lupus Erythematosus- Signalment
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-Collies, Shelties, GSD's, Poodles
-Any age |
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Systemic Lupus Erythematosus- Cx
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-Acute or insidious onset, depending on systems affected
-Shifting leg lameness -Lethargy -Fever -Arrythmias -Muscle wasting Variable pruritis, Erythematous macules, scaling, alopecia, ulceration -Oral and mucocut. ivolvement is com'n |
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Systemic Lupus Erythematosus- Dx
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-Often elusive dx d/t variability of organs affected
-Recognize variable multi-system involvement signs -Photosensitivity -Hematologic disorders **POSTIVE ANA TITER 80-90% OF TIME* |
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Systemic Lupus Erythematosus- Tx
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-Depends upon organ system involved
-Prednisolone -Azathioprine -Chlorambucil -Splenectomy -Cyclophosphamide (for anemia) -Vincristine (for thrombocytopenia) -Chrysotherapy |
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Uveodermatological Syndrome- General
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-AKA- Vogt-Koyanagi-Harada-like syndrome (VKH)
-Rare K9 dermatitis and uveitis |
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Uveodermatological Syndrome- Etiology
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-Unknown etiology
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Uveodermatological Syndrome- Signalment
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-Akitas, Chows, Husky, Samoyeds
-No sex/age discrimination |
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Uveodermatological Syndrome- Cx
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Acute onset of uveitis: photophobia, blepharospasm, corneal edema, blindness
-Glaucoma and cataracts may dvlp -depigmentation of nose -Scale, erythema dvlp |
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Uveodermatological Syndrome- Dx
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-Clinical recognition
-Histiocytic lichenoid dermatitis |
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Uveodermatological Syndrome- Tx
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-Early dx and tx essential to avoid blindness
-Prednisolone -Azathioprine -Opthalmic glucocorticoids and cycloplegics (atropine) |
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Cutaneous adverse drug rxn- General
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-May involve types I, II, III, and IV HS rxns
-Most com'n assoc: in dogs/cats: topical agents, sulfonamides, penicillins, cephalosporins |
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Cutaneous adverse drug rxn- Cx
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-Urticaria
-maculopapular -PF -Exfoliative dermatitis -Inj. site rxns |
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Cutaneous adverse drug rxn- Dx
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-Suspicious Hx and Cx
-D/c suspect drug for 10-14d |
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Erythema multiforme- General
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-EM
-Thought to be cell mediated Hypersensitivity -May be initiated by multiple fx's |
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Erythema multiforme- Cx
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-Acute onset
-Erythematous macules/papules -Target lesion -Vesicles and bullae -Oral ulcers -Urticaris -fever, depression, anorexia |
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Erythema multiforme-Dx
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-Histopath: single-cell apoptosis of keratinocytes throughout epidermis and follicular outer root sheat
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Erythema multiforme- Tx
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-Correct underlying cause
-Immunosuppression may be helpful -Pentoxifylline -Cyclosporine |
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Toxic Epidermal Necrolysis- General
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-AKA- TEN
-RARE, extensive skin dz assoc w/ a poor prognosis -May be a drug rxn causing keratinocyte apoptosis |
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Toxic Epidermal Necrolysis- Dx
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-Histopathology: basal cell hydropic degeneration, full-thickness coagulation necrosis of epidermis
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Vasculitis- General
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-UNCOM'N in dogs
-RARE in cats -Thought to be a Type III HS rxn -Number of causes -50% idiopathic |
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Vasculitis- Signalment
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-Jack russel, Scottie, GSD, Greyhound, Dachshund, Rotties
-Vx rxns more prevalent in poodles, Bichon, silky terriers, yorkies, Pekingese, maltese |
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Vasculitis- Cx
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-Tip of pinnae, footpads, tail tip
-Purpura, plaques, hemorrhagic bullae, papules, pustules, necrosis -Anorexia, depression, fever |
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Vasculitis- Proliferative Thrombovascular necrosis of the pinnae
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-Elongated necrotic ulcer at the pinnal apex
-Dachshunds |
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Vasculitis- Focal cutaneous vasculitis and alopecia secondary to rabies vx
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-Poodles, yorkies, silkies
-Alopecia, scarring dvlp 3-6 mos after vx |
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Vasculitis- Cutaneous and renal glomerular vasculopathy
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-AKA Alabama Rot
-Greyhounds -Limbs, trunk, groin -E-coli toxin in raw beef products |
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Vasculitis- Familial cutaneous vasculopathy of GSD's
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Puppies, fever, lethargy, swollen footpads, Alopecia, crusts
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Vasculitis-Ischemic Dermatopathy
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-Post-rabies vx alopecia
-Plaques, nodules, erosions, ulcers |
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Vasculitis- Tx
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-Tx underlying issue
-Pentoxyfylline -Pred -Dapsone -Vit. E -Azathioprine -Tetracycline and niacinamide |
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Histopath of endocrine dermatoses
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-Impossible to definitively differentiate one from another based on histo changes
-Typically displays numerous telogen hair follicles, follicular dilatation, follicular hyperkeratosis, and a thin epidermis |
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Alopecia X- General
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-Adrenal sex hormone imbalance
-UNCOM'N |
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Alopecia X- Etiology
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-Thought to represent a 21-hydroxylase deficiency (adrenal enzyme)
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Alopecia X- Signalment
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-Pomeranians and plush coated breeds
-1-5 y/o |
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Alopecia X- Cx
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-Progressive loss of primary hair over neck, tail, trunk
-Head/limb hair spared -Hyperpigmentation -Non-pruritic |
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Alopecia X- Dx
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ACTH sex hormone stimulation testing
-Offered by U of Tenn |
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Alopecia X- Tx
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-purely cosmetic
-Melatonin may work -Mitotane is effective but has lots of SE's (kill adr gland) -Tilostane (special FDA approval) safe and effective |
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Hyperestrogenism of intact females- General
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-Ovarian imbalance type I
-Rare in dogs -Very Rare in cats -Middle aged bull dogs |
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Hyperestrogenism of intact females- Cx
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-Bilateral alopecia of the flanks and perineum
-Nipples/vulva enlarged -Irregular estrous cycles |
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Hyperestrogenism of intact females- Dx
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-Ultrasonography
-Measuremt of serum estrogen levels, or response to OVH (may take 1-6 mos) |
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Estrogen reponsive dermatosis of neutered females- General
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-Ovarian imbalance type II
-Rare in dogs -Dachshunds and Boxers more often |
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Estrogen reponsive dermatosis of neutered females- Cx
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-Infantile nipples/vulva
-Diffuse alopecia of trunk begins at flanks/perineum |
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Estrogen reponsive dermatosis of neutered females- Dx
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-Based on Cx and response to therapy
-Diethylstilbesterol or estradiol usually effective |
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Hyperestrogenism in males- General
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-Dogs w/ testicular tumors
-Cryptorchid testes are 10x more likely to dvlp tumors |
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Hyperestrogenism in males- Cx
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-Bilateral alopecia
-Feminization -Non-neoplastic testicle atrophied |
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Hyperestrogenism in males- Dx
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-Blood estrogen levels
-U/S of testicles -Histopathology -Response to neuter w/in 3 mos |
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Pinnal alopecia of Dachshunds
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-Usually males
-Slow onset ~6 mos old -Bilat pinnal alopecia |
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Alopecia of American water spaniels ad Portugues water dogs
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-Onset ~6 mos old
-Ventral neck, caudomedial thighs, and tail alopecia |
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Greyhound Bald thigh syndrome
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-Caudal/lateral thigh alopecia
-may be related to stress of racing |
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Regional pattern baldness
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-Usually females
-Hypotrichosis involving postauricular, ventral neck, ventrum, and caudal thigh regions |
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Follicular Dysplasia- General
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-Weak hairs are susceptible to breakage d/t rubbing
-Regrowth is thinner/weaker |
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Follicular Dysplasia- Cx
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-Cx varies w/ breed
-Husky and malamute -Onset at 3 mos - 4 yrs -Progressive loss of primary guard hair on the trunk -Doberman, min-pin -Onset 1-4 yrs in black/red dogs -Progresses from flanks to dorsal trunk -Irish / portuguese water dogs -Hair loss over cd dorsum to most of trunk -Regrowing hair is of a coarse texture |
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Seasonal Flank Alopecia
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-Localized follicular dysplasia
-Spring/fall Regrowth in 3-6 mos -Alopecic patches have distinct borders and dvlp hyperpigmxn -Melatonin may be effective |
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-Color dilution alopecia
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-Blue dilutions/ fawn dilutions of darker colors
-Dobies, Dachshunds, Gread danes, Whippets, chows -Lg macromelanosomes w/ irregular distribution in hair shafts -Dorsal distribution -Bacterial folliculitis com'n -Tx usually unrewarding |
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Solar Dermatitis
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-UVB--> sunburn cells (vacuolated keratinocytes)
-Incr. histamine, PG's, Inflamm CK's, O2 radicals |
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Feline Solar Dermatitis- General
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-Affects pinnae, eyelids, and/or nose of cats that are white in those areas
-May progress to SCC |
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Follicular Dysplasia- Tx
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Photoprotection
-Sun avoidance -Sunscreen -Beta-carotene -Synthetic retinoid tx (Acetretin) $$$ -Ear tip amputation |
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Burns- Partial thickness
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Burns involve the epidermis and superfical dermis
-Epithelializatino w/o scarring is possible |
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Burns- Full thickness
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Burns involve the deep dermis including all cutaneous structures
-Second intention healing and scarring result |
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Burns d/t heating pads/cage driers cx
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-results in hard and dry skin
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Burns d/t chemicals, electric, microwaves cx
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-These burns appear erosive and/or necrotic
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Burns- Tx
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-Fluid therapy
-Pain mgmt -Topical abx against Pseudomonas spp- Silver sulfadiazine -Surgical debridement/excision |
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Chronic radiant heat dermatitis
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Alopecia, erythema, ulceration d/t chronic use of wood stoves, infrared lamps
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Ichthyosis- General
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-Rare congenital dz w/ excessive scale and hyperkeratosis
-WHWT predisposed |
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Ichthyosis- Cx
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-Hyperpigmented and scaly at birth
-Peeling by 2 wks old -Hyperkeratosis of footpads and planum nasale |
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Ichthyosis- Tx
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Management best care
-Frequent bathing -Emollient shampoos/rinses -Acretin may be helpful -Chronic dz |
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Ehler-Danlos Syndrome- General
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-AKA- Cutaneous asthenia, dermatosparaxis
-Rare dz causing hyperextensibility and fragility of skin -Abnormal collagen synthesis or fiber formation -Various modes of inheritance |
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Ehler-Danlos Syndrome- Cx
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-Skin hyperextensibility
-Skin easily torn -Decreased elasticity -Scars from prev injuries -Jt laxity -Lens luxation -Cataracts |
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Ehler-Danlos Syndrome- Tx
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-Poor prognosis requires dedicated owner
-Maintain injury-proof environment -Repair lacerations as they occur -Declaw cats |
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Idiopathic Primary Seborrhea- General
|
Com'n hereditary keratinization abnormality
-Epidermal cell renewal = 8d in affected dogs, 21d in normal dogs |
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Idiopathic Primary Seborrhea- Signalment
|
WHWT (autosomal recessive)
-Cocker spaniel, bassets, English springer spaniel |
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Idiopathic Primary Seborrhea- Cx
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-Severe seborrhea by 12-18mos
-Ceruminous, hyperplastic otitis externa -Dull, scaly coat -Greasy, stinky -Alopecia, scale, erythema around eyes |
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Idiopathic Primary Seborrhea- Dx
|
-Rule out causes of 2ndry seborrhea
-Histopath--> Follicular hyperkeratosis, perivascular dermatitis |
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Idiopathic Primary Seborrhea- Tx
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Long-term mgmt required
-Antiseborrheic shampoo -Control secondary pyoderma and Malassezia dermatitis -Synthetic retinoids may help (acitretin) -Vit. A therapy -Pred may help |
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Schnauzer comedo syndrome
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-Hereditary condtn of min schnauzer
-Multifocal comedones and crusted papules |
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Idiopathic facial dermatitis of Persians/Himalayans
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-AKA- Dirty face syndrome
-Idiopathic -Periocular, muzzle, perioral, ear and chin rgns -Brown/black exudate on skin/hair -Tx often unrewarding |
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Sebaceous adenitis- General
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-UNCOMMON
-Unknown etiology -Lesions more com'n in long-haired dogs |
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Sebaceous adenitis- Lesions in long-haired dogs
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-Prominent follicular hyperkeratosis
-Dull, brittle hair -Patches of alopecia and abnormally coarse, straight hair -Ceruminous otitis externa com'n |
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Sebaceous adenitis- Tx
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-Long-term bathing programs with antiseborrheic shampoo
-Soak w/ prop.glycol or oil mixtures prior to shampooing -Acecretin and Atopica have been used |
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Idiopathic Nasodigital hyperkeratosis
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-Hyperplastic keratin on the nasal planum and footpads
-Idiopathic -May also be seen w/ other dermatoses |
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Plasma cell pododermatitis
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Rare, idiopathic dz of feline footpads
-Swollen, soft, finely scaled pads -Histo--> plasmacytic dermatitis -Polyclonal gammopathy may be present |
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Canine familial dermatomyositis
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Hereditary and idiopathic inflamm dz
-Collies mostly -Onset 6 wks-6 mos -Alopecia, erythema, scales, crusts, ulcerations -Muzzle, periocular, ear tip, tail tip, carpus/tarsus -Myositis seen later -atrophy of musc of mastication |
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Canine familial dermatomyositis- Tx
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-Avoid physical trauma
-Vit. E -Pentoxifylline -Pred |
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Idiopathic sterile granuloma and pyogranuloma syndrome
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Uncom'n, affects all breeds
-Multiple non-pruritic papules, nodules, plaques on nose, muzzle, pinnae, paws -Alopecia and infxns secondarily |
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Idiopathic sterile granuloma and pyogranuloma syndrome- Tx
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-Sx excision of solitary nodules
-Pred -Azathioprine |
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Sterile juvenile granulomatous dermatitis and lymphadenitis- General
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AKA- Puppy strangles, juvenile cellulitis/pyoderma
-Unknown etiology -3wk - 4mos -Pred for tx |
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Tympanic mb parts
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Pars tensa (ventral)
Pars flaccida (dorsal) Stria mallearis (manubrium of the malleus) |
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Further diagnostic procedures of the ear
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-Ear mite prep
-Bacterial C & S testing -Radiography -CT, MRI -Tympanometry (waves shot at and measured as they bounce back) -Palpation of the TM with a catheter (don’t do this one) -Histopathology |
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Com'n bacteria found in the ear
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-S. intermedius
-Pseudomonas spp. -Proteus spp. -E. coli -Klebsiella spp. |
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Com'n yeast found in the ear
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-Malassezia pachydermatis
-Candida albicans |
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Principles of therapy- Ear dz's
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-Control predisposing, secondary, perpetuating factors
-Ear cleaning -Topical Tx -Systemic Tx -Re-evaluate |
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Ear cleaning and drying agents- Saline
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-Safe, used to get our ceruminolytics
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Ear cleaning and drying agents- Antimicrobials
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-Chlorhexidine
-Provodone-iodine |
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Ear cleaning and drying agents- Oil-based ceruminolytics
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-Help soften and dislodge debris in ears
-Squalene, Propylene glycol, min oil, glycerin |
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Ear cleaning and drying agents- Water based ceruminolytics
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-Dioctyl Sodium Sulfosuccinate (DSS)
-Calcium sulfosuccinate -Carbamate peroxide |
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Ear cleaning and drying agents- Alcohol-based drying agents
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-Boric acid
-Benzoic acid -Salicylic acid |
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Cerumene
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-Safe to use when the TM is torn, least likely to cause ototoxicity
-made up of: squalene isopropyl myristate, petrolatum |
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EpiOtic
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Made up of:
Salicylic acid, prop. glycol and lactic acid |
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OtiCalm
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Made up of:
Salicylic acid, benzoic acid, malic acid, oil of eucalyptus |
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Com'nly used drugs for compounding ear medications
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-Silver sulfadiazine
-Amikacin -Enrofloxacin -Ticarcillin (for Pseudomonas) |
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Systemic Tx for ear infxns
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Abx
-Enrofloxacin, Marbofloxacin, Cephalexin Antifungal -Ketoconazole Corticosteroid -Pred Acaricide -Selamectin |
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Tx for stenosis of ear canal d/t hyperplasia
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-Course of high dose prednisone
-Infuse with cortisone |
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Myringotomy
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Puncture TM to Tx mid ear
-5 o'clock left ear -7 o'clock right ear Heals w/in 3-5 wks |
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TECA- Complications
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-Horner's syndrome
-Facial n. paralysis -Abscessation -Hearing loss |
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Mycosis Fungoides- General
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-Uncom'n, affects both cats/dogs
-Generally of T-cell origin |
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Mycosis Fungoides- Cx
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-Generalized
-pruritis, erythema -Mucocutaneous -Erythema, ulcers -Oral mucosal dz -Ulcerative |
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Mycosis Fungoides- Tx
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-Grave prognosis (5-10mos)
-Systemic/topical chemotherapy -Synthetic retinoids -Interferon |
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Canine Oral papillomatosis
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-Com'n
-Multiple smooth papules and plaques -Progress to cauliflower-like masses |
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Cutaneous inverted papillomas
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-Young dogs
-Ventral abdomen -1-2cm plaque w/ central core |
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Papillomatosis- Histopath
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-Papillated epidermal hyperplasia
-Ballooning degeneration -Clumping of keratohyaline granules -Basophilic intranuclear incl bodies |
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Papillomatosis- Tx
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-Observation w/o tx
-Cryotherapy -Laser sx -Surgical excision |
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Keratoacanthoma
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Intracutaneous cornifying epithelioma
-Uncom'n -Histopath- similar to papilloma w/ no ballooning degeneration |
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Basal cell carcinoma
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-Com'n in cats, not dogs
-Low grade malignancy -Generally solitary, melanotic, rounded nodules on the nasal planum/eyelids |
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Sebaceous gland tumors
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Com'n in dogs, not cats
Older dogs Limbs/trunk Cauliflower-like |
