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30 Cards in this Set
- Front
- Back
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Vescicle definition
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Circumscribed
Fluid containing Epidermal elevations Size < 5 mm May transform into a bulla or pustule |
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Bullae definition
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Rounded or irregularly shaped raised lesions
Fluid-filled with serous or seropurulent material Size > 5 mm |
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Pustules definition
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Circumscribed, raised lesions
Contain a purulent exudate Pus is composed of leukocytes with or without cellular debris |
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Herpes simplex overview: transmission, clinical features, diagnosis
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Worldwide distribution
ds-DNA virus HSV-1 (orolabial); HSV-2 (genital) Primary, latent and recurrent infections Transmission can occur during asymptomatic and symptomatic periods of viral shedding Clinical features: - asymptomatic infection - primary infection: symptoms occur within 3 to 7 days after exposure - prodrome: lymphadenopathy, malaise, anorexia, fever, localized pain, tenderness and burning - painful, umbilicated vesicles on an erythematous base - crusting and resolution within 2 to 6 weeks Diagnosis: Tzanck smear (look for multinucleated epithelial giant cells), DFA, culture, PCR |
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Orolabial herpes
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“Cold sore” or “Fever blister”
HSV-1 in 95% of cases Prodrome more common and severe in primary lesions: tingling, itching or burning sensation Mouth and lips are most common sites Recurrent lesions on vermilion border of the lip Variable symptomatology: local discomfort, headache, nasal congestion, flu-like symptoms Sun exposure is a trigger |
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Genital herpes
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HSV-2 in 85% of cases
Spread by sexual contact Primary infection lasts 7-14 days: grouped vesicles and erosions in the vagina, rectum, penis Fever, flu-like symptoms, vaginal pain and dysuria Recurrent lesions can be limited in severity with resolution within 1 week |
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Herpetic whitlow
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HSV infection of the digits
Affects children and did affect dentists, dental hygienists and health care workers who did not use gloves Tenderness and erythema on the lateral nail fold Deep-seated vesicles develop 24-48 hours after contact |
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Herpetic keratoconjunctivitis
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Common cause of blindness in USA
Edema, tearing, photophobia, preauricular lymphadenopathy Recurrent episodes with unilateral involvement are common Complications include corneal ulceration and scarring |
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Varicella zoster virus
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VZV: varicella (chicken pox) and herpes zoster (shingles)
Varicella is usually symptomatic (very itchy) Before the varicella vaccine occurred in 90% of children < 10 years of age Herpes zoster represents reactivation of latent varicella infection and develops in 20% of healthy adults and 50% of immunocompromised patients |
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Varicella - chicken pox
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Transmission: airborne droplets or direct contact with lesions
Incubation period is 11-20 days Extremely contagious until all of the vesicles have crusted Prodrome of fever, malaise and myalgia Pruritic erythematous macules, papules that evolve into vesicles over 12-14 hours Scalp and face then spreading to trunk and extremities Vesicles with clear serous fluid and red halos Older lesions evolve to pustules and crusts and heal within 7-10 days Self-limited course in healthy children Complications: secondary bacterial infection, encephalitis, Reye’s syndrome (rare) Adults present with more severe disease, pneumonia, glomerulonephritis, optic neuritis, arthritis, myocarditis Treatment: early acyclovir in adolescents and adults, antipruritic lotions, oatmeal baths, keep environment cool |
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Herpes zoster: latency, reactivation, clinical symptoms, course, complications, diagnosis, treatment
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After natural infection or immunization, virus remains latent in the sensory dorsal root of ganglion cells
Immunosupression, old age, stress, fever, radiation therapy can cause reactivation Intense pain, pruritus, tingling, tenderness Grouped vesicles on an erythematous base along a dermatome Usually trunk but face, neck, scalp or extremity Course: 10-21 days until clear Viral shedding the first week May recur in 5% of patients Complications: post-herpetic neuralgia, secondary bacterial infection, scarring, pneumonitis, meningoencephalitis and hepatitis Diagnosis: clinical, Tzanck prep, PCR, biopsy Treatment: analgesics, thymidine kinase inhibitors (acyclovir, valacyclovir, famciclovir), antibiotics Post-herpetic neuralgia: local applications of heat, capsaicin, lidocaine 10% gel, nerve blocks, systemic steroids, tricyclic antidepressants, gabapentin, hypnosis, healing touch |
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Scabies: transmission, symptoms,
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Caused by the itch mite Sarcoptes scabiei
Transmitted directly by close personal contact, sexual contact or indirectly via fomite transmission In first-time infestation, symptoms appear 2-6 weeks after exposure Recurrent infestation can present within 24 hours Intense pruritus accentuated at night and exacerbated by hot showers Symmetrical red papules and vesicles, excoriations Web spaces, body folds, axillae, genitalia, breasts, elbows, wrists, ankles, buttocks, feet |
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Scabies: diagnosis and treatment
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Diagnosis:
- clinical - mineral oil examination of skin sample under the microscope - biopsy Treatment: - permethrin 5% cream: 2 topical treatments, overnight, from head to toe, 1 week apart - Wash in hot water and dry on high heat all clothing, linens and towels used within the previous week - Crotamiton 10% cream, every night for 3-5 days - Lindane 1% lotion, contraindicated in children < 2 years of age, pregnant, breast-feeding women or patients with neurologic disease - Sulfur 5-10% ointment, very irritating - Ivermectin 200-400 μg/kg, 2 times, 2 weeks apart |
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Dishidrotic eczema
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Pompholyx
Precipitating factors: stress, primary fungal, fungal id, drug reaction and idiopathic Sweat glands play a secondary role Itchy, tiny, clear vesicles on sides of digits, palms and soles Skin may become dry, cracked, flaky Episodic flare-up Diagnosis: clinical Differential diagnosis: contact dermatitis, palmo-plantar psoriasis Treatment: topical steroids, light therapy, methotrexate for severe disease, antibiotics for secondary infection, avoid moisture |
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Contact dermatitis
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Clinical: linear distribution, history of exposure
Lesions develop within 1-10 days Causes: poison ivy, oak, sumac, nickel, rubber, thimerosal, neomycin, latex preservatives Treatment: remove agent, apply corticosteroids |
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Diseases with vesicles
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Herpes Simplex
Varicella Herpes Zoster Scabies Dyshidrotic eczema Contact Dermatitis |
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Diseases with bullae
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Bullous Impetigo
Erythema Multiforme Pemphigus vulgaris Bullous Pemphigoid |
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Bullous impetigo
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Common, highly contagious bacterial skin infection in children
Clinical: single or few blisters, annular lesions anywhere on body (more commonly on face and hands) Diagnosis: Gram stain, culture: S. aureus Treatment: mupirocin 2%, systemic antibiotics Complications: Staphylococcal scalded skin syndrome, glomerulonephritis, scarring |
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Erythema multiforme
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Acute, self-limited, recurrent disease
Clinical: abrupt onset of symmetrical red papules, measuring 1-2 cm, targetoid lesions on dorsa of hands, forearms, palms, neck, face and trunk. Mucosal involvement occurs in 25% of the cases Precipitating factors: - Infections: herpes simplex (50%), Orf, Histoplasma capsulatum, mycoplasma pneumoniae - Radiation therapy - Medications: sulfa |
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Pemphigus vulgaris
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Autoimmune disease
Equal frequency in men and women Affects individuals in their 5th or 6th decade of life Thin-walled, big, flaccid, easily ruptured bullae Symptoms appear first in the mouth (60% of cases) and spread to scalp, face, neck, axillae, groin or genitals Nikolsky sign: absence of cohesion in the epidermis Direct immunofluorescence shows intercellular deposits of IgG Treatment: silver sulfadiazine 1%, systemic corticosteroids, other immune modulating agents (azathioprine, cyclophosphamide, methotrexate) |
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Bullous pemphigoid
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Autoimmune disease, affects individuals in the 6th or 7th decade of life
Intense pruritic eruption with large tense bullae Most often begins on lower extremities. Other sites: groin, axillae, flexor surfaces of forearms Associated with diabetes mellitus, rheumatoid arthritis, dermatomyositis, ulcerative colitis, lymphoproliferative disorders Direct immunofluorescence shows linear deposits of IgG and C-3 along the BMZ Use salt-split skin for indirect immunofluorescence Treatment: corticosteroids (lower doses than PV), immunosuppressives agents (azathioprine, methotrexate, mycophenolate mofetil) |
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Diseases with pustules
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Acne vulgaris
Acne rosacea Folliculitis Candidal intertrigo |
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Acne vulgaris
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A chronic inflammatory disease of the pilosebaceous unit
Acne is a follicular process The primary lesion is the comedon whose rupture results in inflammation leading to papules, pustules, or cysts Acne is the most common dermatologic condition treated by physicians in the U.S. It affects 40-50 million individuals/year Acne can occur at any age, more common in teens: -85% of 12-24 year olds -3% of 35-44 year olds |
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Acne classification
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According to lesion type:
- Comedonal (black head), papulopustular, cystic According to severity: - Mild, moderate, severe |
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Acne treatment
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Topicals:
- Tretinoin - Benzoyl peroxide - Antibiotics - Azelaic acid - Salicylic acid - Alpha-hydroxy acids Oral: - Antibiotics: doxycycline, minocycline - Estrogens (oral contraceptives) - Retinoids: isotretinoin - Antiandrogens: spironolactone |
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Rosacea
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Most common in fair-skin individuals
It affects people in 3rd or 4th decade of life Pathogenesis related to vascular hyper-reactivity Triggers: hot drinks, red wine, spicy food, soy sauce, oral niacin, topical steroids |
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Rosacea clinical variants
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Vascular rosacea: flushing and facial erythema with or without telangiectasias
Papulopustular rosacea: central facial erythema with papules or pustules Ocular rosacea: foreign body sensation, burning, dryness, itching, ocular photosensitivity, blurred vision Granulomatous rosacea: firm, brown or red papules or nodules |
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Rosacea treatment
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Systemic:
Doxycycline, 40 mg qd Tetracycline, 250 mg bid Minocycline 100 mg qd Topical: Metronidazole 1% gel qd Sodium sulfacetamide 10% wash or cream qd Azelaic acid 20% bid Erythromycin 2% lotion bid Clindamycin 1% lotion bid Telangiectasias: Laser treatment Rhinophyma: Laser, cryosurgery, electrosurgery |
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Folliculitis
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Clinical: pustules at hair follicle, located especially on the extremities
Diagnosis: culture, clinical -Staphylococcus aureus (normal inhabitant of anterior nares in 20% adults) Complications: rupture of follicle can lead to a carbuncle or furuncle Treatment: antibacterial soap, oral antibiotics, mupirocin |
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Candidal intertrigo
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Typically caused by C. albicans but other species can cause infection
Red, moist areas with satellite papules and pustules on the groin, under breasts, abdominal fat, axillae Diagnosis: clinical, KOH, culture Treatment: topical antifungals, Silvadene, zinc oxide, oral antifungals (fluconazole, itraconazole) |
