Dermatology continued Flashcards
What are the 4 steps of the approach to a dermatology patient?
- collect a dermatologic history
- perform dermatologic examination
- generate a problem list and list of DDX
- perform appropriate diagnostic tests based on DDX
What are 12 important questions to ask?
- breed
- symptoms
- age
- length of disease, progression
- seasonal?
- parts of body affected, where started
- other clinical signs
- food
- other animals? symptoms?
- previous treatment and response
- parasite control
- last medication and bath
Why is important to know the breed?
certain breeds are predisposed to certain diseases
persian cat–dermatophytosis
Why is important to know the breed?
certain breeds are predisposed to certain diseases
persian cat–dermatophytosis
Why is important to know the symptoms?
b/c different symptoms point toward different diseases: like alopecia without pruritus indicates demodicosis or endocrine skin disease while pruritic dermatitis with skin that appears normal indicates atopci dermatitis. Presence or absence of dermatitis is very important
why is it important to know age?he
young animals more likely to have congenital or hereditary defetcts, parasites or dermatophytes, old animals more likely to have allergy of neoplasia and middle aged animals more likely to have allergy or hormonal disease
why is important to know duration and progression?
because sarcoptes, fleas and other parasites usually cause rapid onset of severe pruritus, while allergic skin diseases usually progress more slowly
why is important to know if disease is seasonal?
atopic dermatitis, flea allergy dermatitis, cyclic flank alopecia can be cyclic
why is important to know the sites of of the body affected?
because certain diseases affect different regions of the body
Tail and rump most likely for flea allergy dermatitis
Why is important to know if there are other clinical signs?
because atopic dogs may exhibit upper resp symptoms or more bowel movements indicates food allergy. PU/PD, lethargy indicates endocrine disease
Why is important to know if there are other clinical signs?
because atopic dogs may exhibit upper resp symptoms or more bowel movements indicates food allergy. PU/PD, lethargy indicates endocrine disease
Why does it matter if other animals are affected?
contagious
Why does it matter if the disease was treated?
need to see if animal improved
why does it matter if parasite control was used?
fleas etc can be ruled in ruled out
Why does it matter when the animal last used medication or were given baths?
because recent administration may alter clinical appearance and result of tests. Cytology, skin biopsies, bacterial and fungal cultures and allergy tests can be affected by medications
What does pain on opening the mouth suggest?
otitis media
What does pain on opening the mouth suggest?
otitis media
What should the pinnae be examined for?
alopecia, excoriation, crusts
What should the ear canal be palpated for?
thickening and mineralization
what does otoscopic examination allow?
visual assessment of the vertical ear canal and typmanic membrane
What is the normal appearance of the ear canal and tympanic membrane?
- ear canal is pink and smooth with a small amount of wax
- tympanic membrane is semi-transparent and slightly concave. the lower transulcent part is the pars tensa and the malleus is visible somewhat rostrally
What should the abnormal ear canal be checked for?
- erythema
- discharge
- degree of stenosis
- proliferation/hyperplasia of the ear canal lining and ulceration
What are primary dermatologic lesions?
- macule
- papule
- pustule
- vesicle
- wheal
- nodule
- tumor
What are lesions that may be primary or secondary/
alopecia
What are lesions that may be primary or secondary?
- alopecia
- scale
- crust
- follicular cast
- comedo
- hyperpigmentation
What are secondary dermatologic lesions?
- epidermal collarette
- erosion
- ulcer
- lichenification
- fissue
What are 15 dermatological techniques
- skin cytology
- aspirates
- skin scraping
- clear tape preparation
- flea examination
- trichogram
- wood’s lamp examination
- dermatophyte fungal culture
- bacterial or fungal culture
- skin biopsy
- intradermal allergy testing
- serum testing for allergen-specific IgE
- Bloodwork and endocrine testing
- elimination diet trial
- ectoparasite treatment trial
Why do skin cytology?
Tells more about what is going with the skin and quickly.
How is cytology collected?
- impression
- swab
- scraping
- tape
Why do aspirates?
useful for assessing nodules, tumors and cysts
can find content of lesions without surface contamination
Why do skin scrapings?
indicated for mite and louse infestations.
Why do skin scrapings?
indicated for mite and louse infestations.
Why do clear tape preparation?
To find some surface dewllers like cheyletiella, lice, poultry mites adn fur mites
How can you find fleas?
by parting hair on caudal dorsum and turning pet over, using flea comb or looking for flea feces
How is a trichogram performed
by using forceps to forcefuly pluck hair and place a drop of mineral oil and examine under low power
What is Wood’s lamp used for?
to find microsporum canis dermatohyte infections–50% cause apple-green fluorescence of trpytophan metabolites under UV lights
When is culture indicated?
- deep pyoderma
2. numerous rod-shaped bacteria
Why do skin biopsies?
1 when dealing with serious or poorly responsive skin disease
- if neoplasia, immune mediated disease or conditions only found on histology are suspected.
- if skin lesions appear unusual
- to rule out uncommon differential diagnoses
Why is intradermal allergy testing performed?
1/ in pets diagnosed with environmental allergies (atopic dermatitis)
Why is intradermal allergy testing performed rarely in general practice?
- it takes a lot of experience
2. maintaining test kits is quite expensive
Why is intradermal allergy testing performed rarely in general practice?
- it takes a lot of experience
2. maintaining test kits is quite expensive
Why is intradermal allergy testing performed rarely in general practice?
- it takes a lot of experience
2. maintaining test kits is quite expensive
What is serum testing for allergen-specific IgE used for?
to quntitate circulating allergen-specific IgE levels. not used to diagnose atopic dermatitis, but to ID offending environmental allergens
What is an elimination trial used for?
It is the only way to evaluate food adverse reactions in dogs and cats
What is an ectoparasite treatment trial?
The animal is treated with drugs that are eliminate parasites and can rule out parasites as cause or contributor to pruritus
