Demodex

Question 1

Demodex mites transmission

Answer 1

from mom to pups when they’re 1-3 days old

normal in low numbers in post-natal dogs

Question 2

What makes mites a disease state v. healthy state

Answer 2

abnormal proliferation of mites

Question 3

Pathogenesis of demodex

Answer 3

• deficient immune response
• genetic, juvenile onset
• immunosupressed
• bacterial folliculitis (both demodex and staph live in hair follicle so they go hand in hand)

Question 4

is demodex contagious or zoonotic?

Answer 4

nope

Question 5

clinical signs of demodex

Answer 5

papules/pustules, erythema
alopecia (patchy bc folliculitis) hyperpigmentation
scaling, crusting
**comedones (plugged hair follicles)

Question 6

diagnosis of demodex

Answer 6

deep skin scrape
hair plucks (in area you don't want to plug, eye)
biopsy (sharpei (thick skin), scar tissue, pododermatitis) shows dilated hair follicle full of mites

Question 7

different ages for juvenile onset of demodicosis for different breeds

Answer 7

small breeds <12 mo
large breeds <18 mo
giant breeds <24 mo

Question 8

demodex and _____ are closely related

Answer 8

staphlococcus (both live in hair follicle)

Question 9

benign demodicosis

Answer 9

mites in one area based on 5 deep skin scrape
= localized
*can be bred

Question 10

generalized v. localized

Answer 10

localized is benign, typically won’t recur

generalized

Question 11

progression of localized demodicosis

Answer 11

90% will clear spontaneously (in 6-12 weeks)

10% will generalize

Question 12

Which demodicosis generally has a good prognosis

Answer 12

localized juvenile onset

Question 13

therapy juvenile localized demodex?

Answer 13

1. benign neglect
2. abx (esp. if pustular)
   - topical: 2% mupirocin, benzoyl peroxide gel,
   - systemic if needed
3. de-worming, good diet, HW rx

Question 14

Don’t give to tx localized juvenile demodicosis

Answer 14

steroids
anti-mite therapy
(will predispose to relapse)

Question 15

why wouldn’t you treat localized demodecosis with miticides?

Answer 15

1. you want to know if it will become generalized

2. to prevent unnecessary medical treatment

Question 16

recheck in

Answer 16

2-4 weeks to see if it becomes generalized

Question 17

generalized demodicosis

Answer 17

2+ regions, typically when found on feet is generalized

Question 18

juvenile onset generalized

Answer 18

should be neutered because its genetic
50% will clear
50% will need anti-mite tx (95% of those will resolve 5% will keep relapsing)

Question 19

adult onset generalized

Answer 19

underlying immunosuppression

treat cause

Question 20

treatments to kill mites

Answer 20

*amitraz!
ivermectin
milbemycin

Question 21

Amitraz

Answer 21

only FDA approved tx

• clip hair short and bathe with benzoyl peroxide to open the follicle before dipping (let air dry)
• dip weekly
• not used often anymore
• toy breeds, immunosuppresed at risk for toxicity - sedation
• avoid with diabetes

Question 22

Ivermectin

Answer 22

off label
400-600mcg/kg (.4-.6ml/kg) daily (no collies, shelties)
- build up dose slowly!

Question 23

treat generalized demodex until

Answer 23

several negative scrapes

Question 24

Moxidectin

Answer 24

advantage multi

- weekly, systemic absorbtion

Question 25

Bravecto

Answer 25

highly effective
one pill last 12 weeks
safe for MDR1 breeds!

Question 26

monitoring generalized demodicosis

Answer 26

deep scrape, incuding muzzle and feet every 4 weeks, until 3 consecutive negative scrapes, then can stop the anti-mite therapy

Question 27

stop antibiotics

Answer 27

once you get a negative scrape

Question 28

recheck a generalized demodex case

Answer 28

1 month later
then 3 months later
then 6 months later

Question 29

feline demodex

Answer 29

d. cati

d. gatoi

Question 30

demodex cati

Answer 30

follicular, long narrow
like canine demodex
diagnose with deep skin scrape

Question 31

d. gatoi

Answer 31

stratum corneum, fatter mite
behaves like sarcoptes
contagious, doesnt have to do with immunosuppresion
diagnose with superficial skin scrape

Question 32

tx d. cati

Answer 32

dont use amitraz!
- ivermectin, lym dip, advatage multi
-

Question 33

tx. d. gatoi

Answer 33

• lym dip

- have to treat all animals in contact with the cat