05 - folliculitis and demodicosis

Question 1

1. folliculitis = ?
2. what is the usual resulting clinical lesion?
3. what other 3 things are associated with folliculitis?

Answer 1

1. inflammation of the hair follicle
2. circular area of alopecia with scale and hyperpigmentation
3. papules, pustules, and epidermal collarettes

Question 2

1-3. What are the three main differentials for folliculitis?

Answer 2

1. bacterial pyoderma
2. demodicosis
3. dermatophytosis

Question 3

(demodicosis)

1. caused by what?
2. how easy to cure?
3. life cycle spent where?

Answer 3

1. demodex canis

(small amount normal, ^ in dz)

2. very difficult
3. entirely on dog

Question 4

(demodicosis)

1. how do dogs get these?

Answer 4

1. spread from bitch in first 3 days of life

(nursing provides direct contact for transmission -> muzzle and forelegs are first sites of infestation)

Question 5

1. is demodicosis contagious?

Answer 5

1. no - only in the first few days of life

Question 6

1. it is assumed that dogs with demodicosis also have what?

Answer 6

1. weak immune systems (T-cell fxn abnormality)

Question 7

(localized demodicosis)

1. age?
2. lesions?
3. most commonly affected areas?

Answer 7

1. < 1 yr (usually 3-6 months)
2. localized areas of alopecia, minimal pruritis
3. face (periocular and commisures of mouth), and forelegs

Question 8

(localized demodicosis)

1. tx?
2. rescrape in 3 weeks why?
3. genetic?

Answer 8

1. optimize health - 90% resolve spontaneously in 6-8 weeks
2. to make sure not progressing to generalized form (small number will progress)
3. no

Question 9

(generalized demodicosis)

(juvenile onset - 3-12 months)

1. starts as localized and progresses until it affects all parts of body
2. genetic?

Answer 9

2. yep

Question 10

(generalized demodicosis)

(adult onset)

1. usually how old?
2. may be associated with internal dz, malignancy, or chronic corticosteroid use
3. what two conditions contribute?

Answer 10

1. older than 5 years
2. hypothyroidism and hyperadrenocorticism

(if no cause found changes of successfly treating are decreased)

Question 11

(clinical signs of generalized demodicosis)

1. large areas of alopecia, mild to severe erythema
2. pruritic?
3. skin usually becomes gray of hyperpigmented from what?
4. often get secondary what?

Answer 11

2. not usually
3. chronic inflammation
4. pyoderma (papules, pustules, crusts, exudation)

also can see peripheral lymphadenopathy if pyoderma is present

Question 12

(chronic demodectic pododermatitis)

1. for of generalized demodicosis on feet. remain after therapy or only even on feet

Question 13

(demodicosis)

(otitis)

demodicosis may occasionally occur as an erythematous, ceruminous otitis externa, esp in cats

Question 14

(demodicosis - dx)

1. how to dx?

Answer 14

1. deep skin scraping or hair plucks (trichograms)

Question 15

(localized demodicosis - tx)

1. spontaneous remission so tx usually not needed

Question 16

(demodicosis)

1. Do not use what for tx in these patients?

Answer 16

1. corticosteroids -> cause suspect that immunosuppression is the problem

Question 17

(generalized demodicosis tx)

1. correct any concurrent problems
2. dogs with adult onset should get full work up to check for underlying (immunosuppressive) diseases
3. start on antibiotic tx based on culture and sens, bath with antibacterial and keratolytic shampoo to open hair follicles and remove crusts
4. then tx with what?
5. contintue tx until when?
6. why should female dogs with this disease be spayed?
7. can consider what if mitaban fails?

Answer 17

4. mitaban dips (amitraz)
5. 1-2 months beyond two negative skin scraping 1 month apart
6. estrous cycle can reignite
7. ivermectin (careful with collies!)

Question 18

(demodicosis)

1. juvenile onset should not be bred!