dermatology Flashcards
what is scale
presence of keratin flakes in the hair coat and on the skin
small levels normal
primary diseases that cause scale
primary keratinization disorders - ichthyosis (golden ret)
primary sebhorrhoea
zinc responsive dermatitis
ear margin seborrhoea
naso/digital hyperkeratosis
most common scales
bacterial infection - following pustule rupture circle of scale/hair loss around site
diagnostic plan for scale
check for parasites
check for infection
general health screening
biopsy
genetic testing
scale type treatments 1
zinc responsive - treated with zinc supplementation/anti-inflammatory steroids
golden retriever ichthyosis - symptomatic (and dont breed)
ear margin seborrhoea - incurable, antiseborrhoeic shampoo/moisturiser/surgery
nasodigitial hyperkeratosis - cut off fronds, hydrate the keratin
nasal parakeratosis of labrador - topical vit E, petrolean jelly, propylene glycol
footpad hyperkeratosis - 50% propylene glycol soak
main causes of skin disease
ectoparasites
microbial
allergic
immune mediated
wound
metabolic
neoplasia
common skin diseases in the dog
ectoparasites
infection - staphs, malassezia, dermatophytes, viruses
allergies
neoplasia
endocrine
common skin diseases in the cat
ectoparasites
infections
dermatophytes
allergies
neoplasia
parasitic tests
coat brush - fleas/lice
acetate strip - surface parasotes (cheyletielle, d,gatoi, lice, neotrombicula)
skin scraping - deep parasites (d.canis/cati, sarcoptes)
trichogram - demodex, lice/cheyletiella
what stain should you use on acetate strips
eosin
methylene blue
(no fixative)
when do you only use methylene blue
tape if no need for eosin
waxy ear smears
canine atopic dermatitis
environmental cause of chronic, relapsing, pruritic, inflammatory skin disease
IgE association (not valid for diagnosis)
all pathways proliferate via Janus kinase (oclacitnib (apoquel) targets this)
food atopic dermatitis
any age
not associated with diet change
signs identical to environmental
4 feline atopy presentations
Face, head and neck (FHN)
self-induced alopecia (SIA)
miliary dermatitis (MD)
eoisinohpilic granuloma complex (EGC)
drug eruptions
can present as any type of cutaneous lesion with any hypersensitivity mechanism behind it
how long should a food trial be
min 8 weeks
drugs to control inflammation/pruritis
glucocorticoids/corticosteroids - whole cascade
oclacitnib
lokivetmab - good for pruritis, nothing for inflammation
ciclosporin
treatments to improve skin barrier
moisturisers
fatty acids
essential oils
non-specific scale treatments
keratoplastic/keratolytic shampoos
moisturising/emollient products
salicylic acid
selenium suplide
retinoids - normalise skin development
FAD
cs - dog - scratching, biting (caudal half of dog) cat - head and neck, miliary dermatitis, bilateral symmetrical
dx - combing/intra-dermal tests
tx - flea control
what is pruriceptive pruritis
pruritis due to stimulation of peripheral skin receptors with healthy nervous system
neuropathic pruritis
generated in CNS in response to anatomical lesions, circulating pruritogens, pharmacological
what is SIA
self induced alopecia
bilateral symmetrical alopecia that cat can reach with tongue
stubbley hair with damaged tips
what is the most common cause of face head and neck pruritis
ectoparasites
where do eosinophilic granuloma complexes normally occur
caudal thighs, oral cavity, feet, chin
where do indolent ulcers occur
mucocutaneous junction of upper lips
rarely painful or pruritic
assessment of microbial infection
cytology best
sarcoptic mange presentation
contagious
pinnal crusting
+ pinnal-pedal reflex
treatment - izoxazolines
viral ulceration in cats
feline herpes virus - lesions of eyelids, muzzle and nose
feline calicivirus - vesicles on mucous membranes, lips and nose
plasma cell pododermatitis
soft swollen pads with scaling
plasma cells on FNA
immune modulation - steroids, ciclosporin
treatment of cutaneous lupus
topical - steroid creams/sprays, tacrolimus, anti-septics
systemic - immunosuppression
treatment for mucocutaneous pyoderma
acute - antistaphylococcus antibiotics and chlorhexidine washes, steroids useful
chronic - frequent antiseptic use, intermittent topical steroids
diseases presenting as primary crusting
pemphigus foliaceua
canine juvenile sterile granulomatous dermatitis/lymphadenitis
squamous cell carcinoma
other - feline acne, calcinosis cutis, superficial necrolytic dermatitis, facial dermatitis of persians
canine pemphigus foliaceus
most common autoimmune disease
middle-older
igG response to desmosomal proteins
CS - bilateral symmetrical crusting, lesions usually head/pinane but can appear anywhere. pruritis/mildly unwell
treatment - immunosupression with slow tapering
feline same but lesions around claw folds and nipples
canine juvenile granulomatous dermatitis/lymphadenitis
swelling of muzzle, lips, eyelids, pinnae. pyrexia, depression and anorexia
sterile pustules with ulcers/draining tracts/crusts/hair loss/cellulitis
dx - cytology
treatment - prednisolone
squamous cell carcinoma
feline
older cats, white pigmented areas
uv related
flat firm ulcerated lesions
diagnosis on biopsy
treatment - surgery, radiotherapy
