Dermatology: Dog Pruritis Flashcards
An unpleasant sensation of the skin that provokes the urge to scratch is?
Pruritus aka Itch
You have an owner come in with the complaint of biting, licking, chewing, scratching gnawing, and/or rubbing. What is top on your differential list?
Pruritus
What do we see early on with Pruritus(3)?
Alopecia
Erythema
Excoriations
True or False: Depending on the cause, pruritic skin looks the same in most cases.
FALSE!
Irrespective of the cause. Location is the key.
What do we see in the Chronic stage of Pruritus?
Lichenification
Hyperpigmentation
Seborrhea
True or False: It is important when looking at a pruritic case to look for treatable diseases.
True!
You want to find good/treatable diseases when working up the case.
What does it mean to be systematic in your approach with pruritic cases?
Determine factors contributing to pruritus.
Diagnostically (Derm pushups) & Treatment
Eliminate factors until diagnosis is obtained
Keep owner informed so they understand each step of the process.
What are the 4 differentials for allergy causes of Pruritus in a dog?
Flea allergy
Atopic dermatitis
Cutaneous adverse food reaction
Insect bit hypersensitivity/contact dermatitis
What are the 3 main categories of pruritis in a dog?
Allergy
Ectoparasite
Infections
What are the 5 ectoparasites we are worried about with pruritus in a dog?
Sarcoptes Demodex Cheyletiella Lice Chiggers
What is secondary to Demodex in dogs?
Pyoderma
What are the 3 infections we are worried about with pruritus in dogs?
Staph pyoderma
Yeast
Dermatophytes
You have a dog come in with caudal dorsum pruritus. What is the most likely cause?
Flea Allergy
A dog comes in with pruritus on its elbows and ears. What is the most likely cause?
Sarcoptic Mange
A dog comes in feet licking and chewing. What is the most likely cause?
Atopy or Food Allergy
What does the phrase “rears and ears” refer to?
Food Allergy
What two things can be both seasonal and not?
Flea Allergy
Atopy
*depends on if multiple allergens or geographic location
What 3 things that cause pruritus in a dog is seasonal?
Flea Allergy
Atopy
Insect Allergy
What 6 things that cause pruritus in a dog are not seasonal?
Scabies Food Allergy Flea Allergy Atopy Secondary Infections Demodex
What is the scale for grading pruritus?
Scale of 1-10
Reference point to judge response to treatment
What are the top differentials for a grade 9-10 pruritus?
Scabies
Flea Allergy
Food Allergy
What are your top differentials if pruritus came before lesions?
Allergies
Scabies
What are your top differentials if lesions came before pruritus?
Demodex
Dermatophytes
What are we looking for in a good PE to help narrow down causes of pruritus?
Lesions that confirm historical information
Pyoderma, lesion distribution, hair loss, etc
General health
Immunosuppresion
Ear check
What is the most important thing to check when doing a PE of a pruritus patient?
Ears!
Often Involved!!!
What is important for you to tell the client when they are going to bring their pet in for pruritus?
Do NOT bathe before the visit (for a couple days). You want the organisms to still be there to find.
What are the 5 mainstays of the treatment plan for pruritus patients?
Flea control Treat pyoderma if present Treat Malassezia infection Treat Sarcoptes if suspected Treat ear disease if present
When should you re-assess after treatment for pruritus?
1 week… possibly 2 but no later
True or False: Skin disease are usually cured with one visit.
FALSE
They are rarely cured with one visit
Many chronic ones are ‘life long’ but controllable
Systemic exposure to allergens occurs when _____ in Flea Allergic Dermatitis.
fleas take a blood meal
What type of hypersensitivity is FAD?
Type 1 (antigen-antibody reaction)
What signs do you see with FAD?
Itching
Inflammation
Excoriations
True or False. Flea Allergic Dermatitis is very common.
True!!! Should always be on the list! Use a flea comb every time.
What is it about the flea that causes the hypersensitivity?
Saliva!
Contains many antigens, amino acids, aromatic compounds, polypeptides, phosphorus
Sensitizes the Th cell
What is the classical distribution seen on a pruritic dog that has FAD?
Lumbo-sacral!
What are the primary and secondary lesions seen in FAD on a dog?
P - Papules
S - Crusts
Does FAD show any self inflicted lesions? If so, what are they?
Yes!
Excoriations (itching)
Alopecia
What chronic changes do you see with FAD in a dog?
Lichenification
Hyperpigmentation
True or False. You will always see fleas with FAD.
FALSE.
Fleas or flea dirt may or may not be present. It only takes one!!! Excessive grooming may have removed the fleas.
What is the normal age range for dogs with FAD?
1-3 years old
What differential for pruritus usually has the clinical alopecia sign of “pants”?
FAD
*Dorsal lumbosacral, tailbase, caudomedial thighs, ventral abdomen, flanks