Lecture: Scabies and other parasitic skin dz

Question 1

canine scabies

Answer 1

sarcoptes

Question 2

Feline Scabies

Answer 2

Notoedres

Question 3

Canine Scabies

about

Answer 3

• parasitic, contagious disease
• one species, and many varieties
• zoonotic

Question 4

Sarcoptes

life cycle

Answer 4

• male mite lives on surface of skin
• fertilized femails burrow into stratum corneum
  
  • eggs
  • larvae (6 legs)
  • Nymphs (6 legs)
  • Adult (8 legs)
• life cycle: 3 weeks

Question 5

Sarcoptes transmission

Answer 5

• direct contact
• not part of normal flora
• not resilient in environment

Question 6

sarcoptes pathogenesis

Answer 6

• hypersensitivity
• mechanic irritation
• pruritogenic substances from saliva and feces

Question 7

Sarcoptes CS

Answer 7

• intense pruritis
• predilection for
  
  • ventral abdomen
  • pinnae (margins)
  • Hocks
  • Elbows
• Primary lesions: papule
• Excoriations, crusts, alopecia
• Secondary infections

Question 8

Clinical features chronic sarcoptes infestation (scabies)

Answer 8

• hyperpigmentation
• lymphadenopathy
• weight loss
• hyperglobulinemia

Question 9

Norwegian scabies

Answer 9

• immunosuppressed animals
  
  • glucocorticoids
  • puppies
• rare form
• thick crusts
• numerous mites
• little pruritis

Question 10

Scabies incognito

Answer 10

• well groomed animals
• Intense pruritus
• No lesions

Question 11

Scabies dx

Answer 11

• clinical diagnosis
  
  • intense pruritis
  • papular eruption
  • typical distribution of lesions
• superficial skin scraping
  
  • positive < 50% of the time
  • margins of pinnae, elbows, hocks
• response to treatment
  
  • if you suspect it, treat it

Question 12

scabies

TX

Answer 12

• Topical
  
  • lime sulfur dip (for itching)
  • selamectin (revolution)
  • Fipronil (frontline)
• Systemic
  
  • Ivermectin
  • Milbemycin

Question 13

Scabies

General considerations

Answer 13

• treat all animals with contact
• length of treatment (duration of cycle plus so more than 3 weeks)
• treat secondary infections
• pruritus may get worse before better
• product resistance
• clean environment

Question 14

LymDip

Answer 14

• Faster relief
• strong antipruritic
• yellow staining
• sulfur smell
• drying

Question 15

Selamectin

Answer 15

• label
• suggested regimen 1 dose/2 weeks for 3 times
• won’t kill demodex

Question 16

Ivermectin

Answer 16

• 250-300mcg/kg
• make sure HW negative

Question 17

Notoedric mange

(feline scabies)

Answer 17

• rare, zoonotic disease
• Notoedres resembles sarcoptes
• life cycle: 21 days

Question 18

Notoedric mange

CS

Answer 18

• extreme pruritus
• erythema, crusting, papules
• Distribution
  
  • head and neck
  • generalized

Question 19

Notoedric mange

Diagnosis

Answer 19

• clinical signs
  
  • itchy face, ear pinnae
• superficial skin scrapings
  
  • frequently positive
• response to treatment

Question 20

Notoedric mange

TX

Answer 20

• LymDip
• Revolution
• Ivermectin
• All in contact animals need to be treated
• treatment should extend beyond life cycle

Question 21

cheyletiella

(walking dandruff)

Answer 21

• large, obligate parasite, hook-like mouth parts
• whole life cycle on host
• can live in environment up to 10 days
• zoonotic

Question 22

Three species of cheyletiella

Answer 22

• C. yasguri (dogs)
• C. parasitovorax (rabbits)
• C. blakei (cats)

Question 23

Cheyletiella

CS

Answer 23

• skin irritation and subsequent scratching
  
  • hair loss, scabs, wounds
• digesting enzymes excreted by mite
  
  • mites eat the dissolved skin

Question 24

Cheyletiella

transient zoonosis

Answer 24

• papular eruption and pruritus
• unable to reproduce on human skin
• self-limiting once source removed

Question 25

Cheyletiella Life cycle

Answer 25

* completed in 3 weeks * eggs * larvae (6 legs) * nymphs (8 legs) * Adults (8 legs)

Question 26

Cheyletiella CS

Answer 26

* usually puppies * scaling and pruritus * dorsal distribution

Question 27

Cheyletiella CS in cats

Answer 27

* miliary dermatitis * mild/moderate pruritus * asymptomatic carriers

Question 28

Cheyletiella DX

Answer 28

* Demonstration of eggs or mites * combing technique * superficial scrapings * cellophane tape impressions

Question 29

what drug toxic to rabbits?

Answer 29

fipronil

Question 30

Cheyletiella TX

Answer 30

* Easily killed by most insecticides * pyrethrin * lime sulfur dips * Ivermectin * Fipronil (not on rabbits) * Selamectin * clean environment

Question 31

Pediculosis 2 types affecting dogs

Answer 31

1. biting lice (bigger head w/ jowels) * Trichodectes canis 2. Sucking lice (pointy head) * linognatus setosus

Question 32

Pediculosis about

Answer 32

* host specific **(not zoonotic)** * spends all ife cycle on host * life cycle: 3 weeks

Question 33

Pediculosis more about :-D

Answer 33

* Esp in winter months * Variable clinical signs * asymptomatic-intense pruritus * few direct lesions * secondary excoriations * seborrhea * anemia * matted coat with nits (eggs)

Question 34

Pediculosis DX

Answer 34

* Physical identification of lice and eggs * Brush or acetate tape impression

Question 35

Pediculosis TX

Answer 35

* clip long-haired animals * treat to cover life cycle * easily killed * pyrethrin * fipronil * lime sulfur dips

Question 36

papular diseases

Answer 36

* scabies * ??? * staph * flea allergy/bites