derm CAD Flashcards
question
answer
a dog comes in with lesions on the mouth, crotch, legs, and feet, and arm pits. The owner says this happens every year around the spring. The lesions show erythema and alopecia. The owner says shes not concerned as the dog is not itchy…. A) you suspect atopic dermatitis so you need to rule out ectopic parasites , B) you can rule out atopic dermatitis so you start working up other causes c) its a food allergy so start a diet trial d) its an environmental allergy so you start on steroids
B - if the animal is not pruritic it is not atopic dermatitis
lesions on the rump and some dots on the neck and crotch - what is your 1st differential
flea allergy
lesions on the ears hind hock and the elbow
scabies
what is the distribution of demodex
focal lesions all over the body
you see lichenification in the cubital fold of the dog (front of the elbow)
predilectation site of atopic dermatitis
Cad is a ____ and ____ disease (2 broad side effects), that involves immunoglobulin __ directed most commonly against ____ allergens but sometimes associated with ___ allergens.
inflammatory and pruritic disease, IgE , usualy against environmental but sometimes assocaited with food allergies
what are 5 components that make up the pathogenesis of CAD
genetics, environment, immune system dysfunction, sesnitization to allergens, skin barrier dysfunction, aleration in microbial populations
you have many clients with puppies from the same breeder and they all have signs of CAD. What do you want to discuss with the owners / breeder
there is a genetic component of CAD that increases if both parents have the genes that predispose…. This can affect the inflamm cytokines and skin structural . So they should not breed these animals anymore.
what are some risk factors of CAD
urban environment, male, neutered, allowed on upholstered furniture, receiving flea control, exposure to smoke, being raised in a shed as a puppy, adopted at 8-12 weeks, living in a county with a veterinary dermatologist, regular bathing, chocolate labs vs. other color labs
what are some protective factors associated with CAD
Potential Protective factors: rural, walking in woodlands, fields or beaches, non-commercial diet, raw diet, living with other animals
an owner has a dog you have diagnosed with atopic dermatitis - you’ve ruled out food allergy and explain that environmental allergies are the most common cause. What is the most common cause of environmental allergies for CAD dogs?
dust mites
dust mites is a common cause of CAD. How can an owner help reduce this exposure a) keep a cleaner house b) don’t let the dog roll in dirt c) improve the skin barrier with nutrition and bathing d) use a mite preventative medication
c) improve the skin barrier
what are 2 primary and 2 secondary skin lesions for CAD
priamry - erythema and papules … secondary - excoriation, alopecia, lichenification, moist dermatitis, 2ndary infection
you dx CAD and the owner says the c/s arent so bad and they don’t want to treat … what do you tell them
this disease is progressive and will likely get worse with time
what are the 3 important steps to dx CAD
- rule out other diseases 2. detailed history and c/s 3. demonstrate an IgE component
what are 3 ways we can rule out other causes when working up a case of CAD
- skin scraping or treat for ectoparasites (demodex) 2. cytology (pyoderma) 3. food trials (food allergy)
a dog presents with lesions that make you suspicious of CAD. You take a history: …… Dog lives indoors, is 6 years old, has never had a yeast infection, has lesions on the front feet and pinnae but not on the ear margins or dorsolumbar region… which of these are NOT part of the criteria for ruling in CAD (favrot’s criteria)
AGE = <3years old is more common for CAD, also recurrent yeast infections is more common for CAD (doesn’t mean the dog doesn’t have it ..)
how do you identify a component of IgE with CAD
intradermal skin testing or serum IgE testing
t/f the only way to dx CAD is to do intradermal / serum testing so all owners should do it if they have a dog that presents with potential CAD?
FALSE … only do allergy testing if the owner wants to consider allergen specific immunotherapy … otherwise there is no point because it doesn’t change how we treat the disease
what are 4 ways we can offer to a client to treat CAD
- treat with anti-pruritics and anti-inflammatories 2. allergen specific immunotherapy 3. topical therapy 4. identify and prevent flares
when / why would you prescribe oclacitinib (apoquel)
fast acting for acute flares but less helpful for otitis and pododermatitis. Its relatively safe. No increased risk of neoplasia. Cannot use in animals younger than 12 months
what is the MOA of oclacitinib?
inhibits the cytokines involved with CAD (janus kinase inhibitor)
pros and cons of lokivetmab (cytopoint)
monoclonal antibody against IL - 31. fast acting (useful for flares), it lasts 4-8 weeks but needs an injection, no drug interactions if they are on other drugs, minimal immune suppression
what is the MOA of lokivetmab
monoclonal antibody against IL-31
which drug is : slow acting calcineurin inhibitor starts dose 5 mg/kg and decrease to EOD or less frequent, not useful for acute flares.
modified cyclosporine (atopica)
when / why would you prescribe oclacitinib (apoquel)
acute flares in animals >12months
what are 4 examples of corticosteroids
prednisone - dog, prednisilone - cat, methlypredisolon (medrol) - 1.2x more potent, dexamethasone - 10x more potent
what is the dose and most common steroid used for allergies ?
0.5 mg/kg pred for pruritis and taper down to lowest effective dose …… If you have inflamm otic / pedal conditions = 1mg/kg
you have a large dog with otic inflammationg and pruritis what dose would you use …. A) 0.5 mg/kg and taper predisone B) 1 - 1.5 mg/kg but likely higher in larger dogs c) 1mg/kg but likely lower dose because doses are often lower in larger dogs d) don’t use pred for otic inflammation
C 1mg/kg for otic inflammation and taper down - esp. in larger dogs they often require lower doses
name 5 side effects of pred
PU/PD, polyphagia, muscle atrophy, weight gain, panting, sterioid hepatopathy, iatrogen cushings, GI ulceration, lipidemia, vomiting /diarrhea, immune suppression, hypercoagulability
what are some indications for oral corticosteroids
when other tx don’t work, acute allergic rxns, ear stenosis and severe pododermatitis (essentially ear and foot signs treat better with pred)
t/f topical steroids are stronger than oral because they metabolize to weaker steroids once they enter circulation
true
what are two kinds of topical steroids
(soft steroids: hydrocortisone aceponate, mometason) and topical tacrolimus (its similar to corticosteroids but smaller so good for topical use)
aside from the common antipuritics and topical steroids what are some other options for medical treatment of CAD
antihistamines, vitamin E, fish oils, pentoxifylline, palmitoylethanolamide, dietary modifications (derm diets)
what is the only “TREATMENT” that can decrease disease progression of CAD?
allergen spcific immunotherapy (ASIT)
how does allergen specific therapy work?
first you do a intradermal skin test to see what the specific allergen is promotes a Th1 response that induces T-cell anergy … increases IgG that competes with IgE …. You give low doses of the allergens identified to induce tolerance desensitization
how long does ASIT take to work?
3-9 months (12-18 to see full benefits)… 60 - 80% improvement NOT CURE
which of the 4 anti-pruritics is not used for flares
NOT cyclosporine
what are some common causes of flares or what can we do to reduce flares?
food allergens, ectoparasites, seasonal allergies, medication ingredients, infection (yeast or staph)
what are some chronic treatments of CAD?
oclacitinib, lokivetmab, cyclosporine (combinational therapy possible). Topic treatment (shampoos and ear meds), antifungals / parasitics …. Consider ASIT
what would you do to find out if there is a food allergy cause of CAD?
diet trials ?
how long do food trials take?
8 weeks
t/f you don’t use anti-pruritics during a food trial because it messes up your results
you can use anti-pruritcs at the beginning of the trial (oclacitinib ideally) and stop 1-2 weeks before you challenge the diet
you do a food trial and notice the animal’s c/s have improved…. What are 6 reasons for this improvement
- seasonal 2. placebo, 3. nutraceutical ingrediates, 4. infection has resolved, 5. strict flea control, 6. true food allergy
