Id: Otitis And Malassezia

Front 1

What are the layers of the skin?

Back 1

epidermis and dermis separated from underlying fascia by the hypodermis

Front 2

What are the inner and outer layers of the epidermis?

Back 2

Most inner: stratum basale, Most outer: stratum corneum (keratinized)

Front 3

What structures are part of the dermis?

Back 3

connective tissue, hair follicles, sebaceous and sweat glands, blood and lymph vessels, nerves

Front 4

What is the hypodermis comprised of?

Back 4

connective and adipose tissue

Front 5

What are the immune cells of the skin?

Back 5

Langerhans cells (antigen presenting cells), Mast cells, IgG

Front 6

What is the purpose of the normal skin flora?

Back 6

colonize surface of epidermis and hair follicles and inhibit colonization by other microorganisms

Front 7

What factors influence the quantity and type of resident flora? What type of bacteria predominate?

Back 7

skin pH, moisture, fatty acids, other factors; gram positive bacteria predominate

Front 8

What is the most common normal flora that is a gram negative rod? fungi?

Back 8

gram neg rod: Acinetobacter spp; Fungi: Malassezia pachydermatis, Candida albicans

Front 9

How are the transient flora of the skin acquired?

Back 9

acquired from environment or mucosal membrane flora (remain for days to weeks)

Front 10

What is Otitis Externa? What are the common agents in normal and abnormal ears?

Back 10

inflammation of external ear canal, staph pseudintermidius, Staph felis, beta-hemolytic Strep spp, Malassezia pachydermatis

Front 11

What agents are only found in abnormal ears?

Back 11

gram negative bacteria: Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae

Front 12

What are the predisposing factors of Otitis externa?

Back 12

breed, ear conformation, neoplasms, allergies, seborrhea, environment (moisture, trauma, foreign bodies, cleaning agents), other agents (Otodectes cynotis, demodex, sarcoptes, notoedres)

Front 13

What are the clinical signs of otitis externa?

Back 13

pruritus, head shaking, rubbing of ears against things, head shyness (pain); ear canal is reddened, often swollen, and may have moderate to large amounts of discharge, may have an odor

Front 14

What are some more clinical signs of otitis externa?

Back 14

attempts to scratch ear with ipsilateral hind paw, lesions on pinna and caudal to pinna on head, aural hematomas, severe cases may have head tilt

Front 15

What is dry coffee ground-like debris typical of?

Back 15

ear mite infection

Front 16

What is waxy, greasy, yellow to tan discharge typical of?

Back 16

ceruminous otitis; keratinization disorders, endocrine conditions, chronic hypersensitivity

Front 17

What is moist brown discharge typical of?

Back 17

staph and yeast infections

Front 18

What is purulent creamy to yellow exudate typical of?

Back 18

gram neg infections

Front 19

How is otitis externa diagnosed?

Back 19

otoscopic exam; cytological exam for bacteria, yeasts, mites; DQ stain for bacteria and fungi (>5 yeasts and/or >25 bacteria per high dry field)

Front 20

What is a clinical sign of chronic otitis externa?

Back 20

epidermal hyperplasia with thickening of pinna and narrowing or calcification of the ear canal

Front 21

When is culture and sensitivity used?

Back 21

cases that do not respond to current therapy or that may need systemic abx; take sample within the horizontal ear canal

Front 22

Why is sensitivity testing usually not needed in cases of otitis externa?

Back 22

concentrations of drugs used topically are much greater than what is present in the sensitivity discs

Front 23

What is the treatment of otitis externa?

Back 23

determine and eliminate and/or control predisposing factors; treat proper ear cleaning; topicals; systemic abx (middle ear infection or topicals can't be applied to ear)

Front 24

What is the etiologic agent of Malassezia Dermatitis? morphology?

Back 24

Malassezia pachydermatis; lipophilic yeast found as commensal on skin and mucocutaneous areas of dogs and cats

Front 25

Where on the animals are the highest numbers of M pachydermatis found?

Back 25

chin and lips, external ear canal, perianal regions, and dorsal interdigital areas

Front 26

What are the clinical signs of infection with M pachydermatis?

Back 26

pruritis, alopecia w/ erythema (reddened), seborrhea, hyperpigmentation, lichenification (thick and scaley), sour smell

Front 27

Where on the animal are common affected areas?

Back 27

interdigital, ventral neck, perianal, face, and axillary regions

Front 28

What are the predisposing factors that allow proliferation of the yeast?

Back 28

allergies, seborrhea, excessive bathing

Front 29

What causes clinical signs to develop due to M pachydermatis?

Back 29

allergic reaction to metabolic by-products of the yeast

Front 30

How is infection with M pachydermatis diagnosed?

Back 30

clincial signs, demonstration of yeast cells on skin scraping: small broad-based yeast cells

Front 31

What is the therapy for M pachydermatis?

Back 31

determine and treat predisposing factors; treat topically (shampoos or dips): miconazole, ketoconazole, clotrimazole, nystatin; consider oral azoles; *griseofulvin is ineffective

Front 32

What is the zoonotic potential?

Back 32

very low