Scale Flashcards
Define scale
the presence of flakes of keratinized skin in the hair coat and on the skin.
List 5 things that scale can result from
normal skin function- small amounts normal
abnormal desquamation
Abnormal cornification
Inflammation
Bacterial and fungal enzymatic action
what is crust
result from the hardening of pus, serum and/or blood with scale to form a solid material which like scale is variably adherent to the skin
What is more common primary or secondary scale
secondary scale much more common
what is the most common form of scale
scale secondary to bacterial infection
the amount of scale depends on bacterial toxins
Decsribe the diagnostic plan in cases of scale
- check for parasites
- check for infection
- older animals- general health screening (e.g. biochem, urinalysis, haem)
- Biopsy
- Genetic testing if indicated
Describe Type 1 Zn-respinsive dermatosis
Genetically predisposed breeds eg Husky (type I)
Don’t absorb Zn very well - often young adult
see dull coat and specific hard plaques with marked scale and crusting
what is Zn needed for in the skin
Zinc is required for normal keratinisation
Describe how to treat Zn-responsive dermatosis
Zn supplementation (zinc sulphate - can cause v+)
correct diet
what is typically seen with ichthyosis of the golden retriever
seen from few weeks of age- scale is variable over life but can be severe
symptomatic treatment only
is a genetic disease
Describe canine ear margin seborrhea
uncommon - seen in dachshunds
thick white crust around ear margin
rubbing of these produces erosions and ulceration
Describe how to treat canine ear margin seborrhoea
incurable condition
surgery- can perform edge resection
medical- topical anti-seborrhoeic shampoos, combined with moisturisers
what is Nasodigital hyperkeratosis
A broad term for dogs with non-inflamed, quiescent and tightly adherent hyperkeratosis affecting the nose and sometimes the feet.
what is nasodigital hyperkeratosis associated with
distemper virus
has genetic component?
Desribe how to treat nasodigital hyperkeratosis
cutting off prominent fronds with scissors or a scalpel blade
hydrating the keratin using shampoos and soaks as described elsewhere
Essential fatty acids
Describe nasal parakeratosis of labradour retrivers
First observed between 6 & 12 months
genetic
roughening of nasal skin
treatment is for life- animals should not be bred from
Describe how to diagnose NPLR (nasal parakeratosis of labrador retrievers)
biopsy
genetic testing
Describe how to treat NPLR (nasal parakeratosis of labrador retrievers)
topical vitamin E
petroleum jelly
propylene glycol
Describe Footpad hyperkeratosis of the Dogue de Bordeaux
fist signs at 4-6months
Foot pads only, with severe thickening with deep cracks appearing centrally
Describe how to treat Footpad hyperkeratosis of the Dogue de Bordeaux
50% propylene glycol soaks
antibiotics for secondary infection
retinoids- very expensive
where does callus generally occur
hocks, elbows, sternum and ischium
what are callus
round or oval hyperkeratotic plaque that develops on the skin at points of trauma.
Callus is the normal response to pressure induced ischemia and inflammation.
Describe how to treat callus
treat secondary infection
removal of trauma/pressure
bandaging and padding??
surgery is possible- Don’t really do though
Describe Thymoma induced exfoliative dermatitis
Diffuse, non-pruritic erythema and exfoliation (large 1+ cm flakes if skin) +/- alopecia
Concurrent signs from respiratory compromise
Describe how to treat Thymoma induced exfoliative dermatitis
immunomodulatory drugs
surgery is curative
What is Idiopathic canine sebaceous adenitis
Inflammation in the sebaceous glands resulting in reduced activity to complete loss
not uncommon
List the clinical signs of Idiopathic canine sebaceous adenitis
dry scale- fine
hair loss
Perifollicular hyperkeratosis is prominent
Follicular casts are common
Pruritus when 2˚ infection present
Describe how to diagnose Idiopathic canine sebaceous adenitis
clinical signs highly suggestive
biopsy- will see absent sebaceous glands
Treatment of Idiopathic canine sebaceous adenitis
Use emollient and lubricating shampoos
fatty acid and oil supplementation
ciclosporin
prognosis good if seen early enough
what do Keratoplastic / keratolytic products
do
reduce scale production
but cause excessive drying so need to be used before moisturizing products
what do Moisturising and emollient products
do
These reduce transepidermal water loss and prevent inflammation
Best used after other products have removed scale
what is the action of keratoplastic products
reducing cell turnover in the skin to reduce scale production
e.g. sulphur and tar
what is the action of keratolytic products
the shampoo removes cells from the surface of the skin
e.g. salicylic acid
when do we use Selenium sulphide to treat scale
Older anti-seborrheic but can be used to treat severe cases of oily greasy skin non-responsive to other agents- not used much
causes marked drying
stains coat pink in white animals
Describe nasodigital hyperkeratosis lesions
nasal lesions - nose is dry with hard projections, cracks and fissures may occur
pad lesions - all the pads lack flexibility, they are cracked and corns can form
How do steroids affect keratinisation
reduce turnover of epithelial cells
Describe type 2 Zn-responsive dermatosis
In nutritional restriction seen in young rapidly growing larger breeds
