Crusting disease Flashcards
define crust
dried exudate, containing blood/serum/scales/pus (colloquially a ‘scab’)
Describe how to approach investigation of crust
rule out ectoparasites
rule out microbial infections
Then further investigations if lesions remain, especially biopsy
when is biopsy if crust most diagnostic
if secondary infections cleared first
when biopsing- DON’T dislodge the crust
Dog - pinnal margin crusting
Highly pruritic
+ve pinnal-pedal reflex
Most likley cause
Sarcoptic mange
3yo cat – self trauma to head
Most likely diagnosis
FASS/FFA
8yo GSD
6-month history of nasal depigmentation/ulceration
MOst likely diagnosis
Facial DLE/ mucocutaneous pyoderma
what cytology is very suggestive of pemphigus
Acantholytic keratinocytes (large ‘fried-egg’ cells, sometimes in rafts) + neutrophils
- under crust
Describe the signalment of canine pemphigus foliaceus
Middle aged to older dogs (but can occur at any age)
?male > female
Strong breed predisposition
Is the most common autoimmune skin disease in dog
Describe the pustules seen with pemphigus foliaceus
Often larger and with erythematous margins
Distribution – often includes face/pinnae/footpads - most important to tell it apart from other disease
Lesions bilaterally symmetrical
can only see the crust in most cases
when should you think pemiphigus foliaceus as diagnosis
bilaterally symetrical crusting
commonly lesions on head/pinnae
pyoderma that is unresponsive to rational treatment
Treatment of pemphigus
Immunosuppressive doses of systemic GCC- then taper slowly to lowest effective maintenance dose
can add in adjunctive immunosuppressive agents
prognosis- often poor due to adverse effects of treatment
what is Canine juvenile sterile granulomatous dermatitis and lymphadenitis also known as
juvenile cellulitis
puppy strangles
what do you see with puppy strangles
Acute onset swelling of muzzle, lips, eyelids, pinnae
Marked submandibular lymphadenopathy
Pyrexia, depression, anorexia
- usually in puppies but occasionally adults
diagnosis of puppy strangles
- signalment, CS, history- very suggestive
- rule out other conditions that can cause cellulitits (demodex, bacterial pyoderma, dermatophytosis)
- Biopsy confirmatory
Treatment of puppy strangles
Prednisolone (immunosuppressive doses)
warm soaks, topical washes
ABs not needed unless secondary infection
prognosis of puppy strangles
Good if treat early but may scar if treatment delayed —> may need to treat before histopath results return!
which cats get affected by Squamous cell carcinoma
older cats
usually unpigmented nasal planum, pinna, eyelids
esp white cats
UV related
clinical signs of feline SCC
Usually flat, firm, ulcerated lesions –> tissue destruction
Often crusted. Often >1 lesion
what can preceed feline SCC
actinic (solar) keratosis
erythematous plaque with erosion/ulceration/crust
treatment of feline SCC
depends on size and site of lesion
superficial= respond well
infiltrative tumours- needs aggressive surgery + radiotherapy or adjuvant chemotherapy
how to prevent new feline SCC
sunblock
Keep indoors in strong sunlight
UV light blocking film on windows?
if you have a claw bed infection in a dog that is not responding - what should you think
claw bed canine SCC
is aggressive- need quick treatment
describe feline acne
Dark waxy scales/crust on chin
May be primary disorder, but often secondary (e.g. to dermatophytosis, demodicosis)
what is calcinosis cutis
inappropriate deposition of calcium phosphate in skin/subcutis
–> gritty white deposits –> provoke surrounding inflammation and crust
what is calcinosis cutis generally due to
dystrophic calcification- HAC
Presentation of Superficial necrolytic dermatitis
Hyperkeratosis of footpads
Mild depression, weight loss
Mild lameness
What generally causes superficial necrolytic dermatitis
lesions due to keratinocyte death associated with:
1. end-stage liver disease
2. pancreatic atrophy/ glucagonomas diabetes mellitus
diagnosisi of superficial necrolytic dermatitis
histopathology
relevant changes on haem/biochem
treatment of superficial necrolytic dermatitis
dietary supplementation
treat secondary infections
adress underlying cause
prognosis is poor
what is Idiopathic facial dermatitis of Persians
Tightly adherent, greasy black scales
Malassezia dermatitis
treatment of idiopathic facial dermatitis of persions
Anti-yeast therapy
Ciclosporin ± prednisolone
Guarded prognosis
