Derm Parasites- Midterm Material (653)

Question 1

When a patient presents with pruritus, what are the 3 steps of evaluation?

Answer 1

1) rule out ectoparasites FIRST
2) rule out bacteria/fungi
3) consider allergies

Question 2

DDX for folliculitis in dogs:

Answer 2

1) bacterial (Staph.)
2) demodicosis
3) dermatophytosis

Question 3

DDX for folliculitis in cats:

Answer 3

1) dermatophytosis
2) bacterial (Staph.)
3) demodicosis

Question 4

What is the minimum dermatologic database?

Answer 4

cytology, skin scrape, trichogram

Question 5

Most common flea of domestic small animals scientific name:

Answer 5

Ctenocephalides felis

Question 6

What is the principle host of C. felis?

Answer 6

cats

Question 7

C. felis life cycle:

Answer 7

eggs -> larvae (feed on flea dirt) -> pupae (remain until appropriate host is present- sensitive to CO2, warmth, and shadow/light change) -> adult (require blood meal to reproduce- only life stage on the host)

Question 8

Diseases transmitted by C. felis:

Answer 8

bartonella, Diplydium caninum, Borrelia burgdephori (?)

Question 9

Clinical signs of flea infestation:

Answer 9

pruritus*, multiple pets in home affected, pyotraumatic dermatitis (hot spots)

Question 10

DX for C. felis (flea infestation):

Answer 10

flea comb -> live fleas, flea dirt (smear to see if it looks like blood)

Question 11

TX for flea infestation:

Answer 11

treat ALL pets in home, adulticide +/- growth regulator (adulticide not enough to stop a true infestation if it takes too long to kill)

Question 12

Capstar:

Answer 12

nitenpyram
kills ADULT fleas only in 30 minutes
must be given every 1-2 days -> not ideal for long term, usually only used in clinic

Question 13

Fipronil:

Answer 13

Frontline, etc.
kills adults in 12-18 hours, treats ticks and chewing lice
RESISTANCE
fipronil + S-methoprene (frontline plus) -> killls adults and prevents larvae development

Question 14

Imidocloprid:

Answer 14

kills adults in 12-24 hr.
TOXIC TO BIRDS
Advantix (imidocloprid + permethrin + pyriproxifen) = TOXIC TO CATS

Question 15

Isoxazolines:

Answer 15

RAPID KILL (2-8 hr)
fleas, ticks, mites, lice, ear mites
seizure risk
Bravecto, Simparica, Nexgard, Credelio

Question 16

Sentinel:

Answer 16

lufenuron + milbemycin oxime
prevents larvae development but DOES NOT kill adult fleas!
NOT APPROPRIATE FOR FLEA INFESTATION OR ALLERGIES

Question 17

Vectra 3D:

Answer 17

dinitefuran + pyriproxyfen + permethrin
TOXIC TO CATS
repels fleas, mosquitoes, biting flies and kills fleas, ticks, and lice
associated with pemphigus foliaceus in dogs

Question 18

Adverse effects of permethrin in cats:

Answer 18

ataxia, tremors, twitching, seizures

Question 19

Which superficial mites affect dogs?

Answer 19

Sarcoptes scabiei var. canis

Question 20

Where do the S. scabiei mites burrow?

Answer 20

epidermis (stratum corneum)

Question 21

Reservoir host of S. scabiei mites:

Answer 21

foxes

Question 22

Transmission of S. scabiei:

Answer 22

direct contact, fomites

Question 23

What superficial mites infect cats?

Answer 23

Notoedres cati

Question 24

Which superficial mites are zoonotic?

Answer 24

both S. scabiei and N. cati BUT they cannot reproduce in humans

Question 25

Clinical signs of scabies:

Answer 25

PRURITUS, initial response to anti-pruritics but later worsens acute = erythema, papules, excoriations chronic = type IV hypersensitivity, yellow crust, hyperkeratosis

Question 26

Distribution of lesions for scabies:

Answer 26

dogs: pinna, lateral elbows, lateral hocks, ventrum cats: pinna, head and neck

Question 27

Pinnal-pedal response:

Answer 27

test for scabies infection rub the ear pinnae -> dog lifts leg as if to scratch

Question 28

DX for scabies:

Answer 28

superficial skin scraping (< 50% chance of finding mites- treat empirically) pick area with scale but not excoriated

Question 29

TX for scabies:

Answer 29

treat pruritus (steroids) and secondary infections, isoxazolines

Question 30

Which deep mites infect dogs?

Answer 30

Demodex canis Demodex injai

Question 31

How is D. canis transmitted?

Answer 31

from dams while nursing

Question 32

Distribution of D. canis lesions:

Answer 32

rostral muzzle, periocular, paws

Question 33

Clinical signs of D. canis infestation:

Answer 33

folliculitis (alopecia), comedomes, NO PRURITUS, inflammation

Question 34

What breed may be predisposed to D. injai infection?

Answer 34

fox terriers

Question 35

Differences between D. canis and D. injai morphology:

Answer 35

D. injai is longer and only has 3 pairs of ventral scutes (4 in D. canis)

Question 36

Clinical signs of D. injai infection:

Answer 36

greasy skin, alopecia, scale

Question 37

Which deep mites affects only cats?

Answer 37

Demodex cati Demodex gatoi

Question 38

Distribution of lesions with D. cati infections

Answer 38

face, neck

Question 39

Clinical signs of D. cati:

Answer 39

folliculitis, non-pruritic

Question 40

What is unique about D. gatoi?

Answer 40

PRURITIC, CONTAGIOUS, very small morphologically

Question 41

DX for demodicosis:

Answer 41

deep skin scraping in areas of alopecia and comedomes