Page 1124 - Problem-Based Feline Medicine

1116 PART 13 CAT WITH SKIN PROBLEMS

Deep wedge biopsy from a footpad near the pad mar- Pruritis is present but may not be obvious to the owner.
gin is diagnostic. A punch biopsy may not go deep ● Over-grooming results in non-inflammatory alope-
enough to be diagnostic. cia (“fur mowing”).
● If a number of pads are affected choose a more
Foot or claw chewing may initially be the only pre-
mildly affected one to biopsy as a severely affected
senting clinical sign.
one may not heal well.
● The cat drags the claws through the teeth with loud
clicking noises, which brings the problem to the
attention of the owner.
Differential diagnosis ● One or more ulcerated areas of the paws (digits,
Undifferentiated sarcoma may appear very similar and periungual areas or interdigital spaces) may be
needs a biopsy to differentiate. present.
● Histologically these lesions are typical of eosino-
philic granuloma complex.
Treatment
Diagnosis
This is not necessary if the cat is asymptomatic, as the
disease may spontaneously regress. Rule out other causes of claw problems, especially
infectious pododermatitis and neoplasia.
Immunosuppressive doses of prednisolone (up to
4 mg/kg/day) have been recommended, but may not be Control external parasites. A good choice is fipronil as
effective. this controls fleas, and anecdotally mites (Cheyletiella,
Sarcoptes, Otodectes and Notoedres) and provides partial
Chrysotherapy (aurothioglucose; Solganol; 1–2 mg/kg
control of ticks.
IM weekly) may be effective.
Try a dietary trial using a food source that the cat has
Surgical excision of the footpad. A new footpad
not been exposed to before. It may take ingenuity to
grows back. Reported to be the best therapy at present.
find a new food that the cat is willing to eat. Duck,
venison or rabbit (2/3 cup) with cooked rice or pasta
(1/3 cup) are often tolerated. A trial period of a mini-
Prognosis
mum of 9 weeks has been advocated for cats and up to
Prognosis is guarded as the recurrence rate is high, 16 weeks preferably. Re-challenge the cat with the old
usually within 4–6 months. diet to confirm the diagnosis, although owners may be
unwilling to risk signs recurring.

ATOPY AND ADVERSE FOOD REACTION* Intradermal skin testing to test for atopy. This is tech-
nically more difficult in cats than dogs, as reactions are
less intense and more transient.
Classical signs
● Pruritis, which is manifested as scratching,
licking or chewing. PRIMARY AND SECONDARY NEOPLASIA*
● Skin lesions varying in severity from
alopecia to miliary dermatitis to ulcerated Classical signs
plaques or granulomas.
● Swollen, painful digit(s) and/or paronychia.
● Ulcerative destructive lesion of the paw
and digits.
Clinical signs
Atopy and adverse food reactions result in various
Pathogenesis
other dermatological manifestations such as ulcer-
ated plaques, miliary dermatitis, symmetrical alopecia Neoplasia involving the foot is rare in cats and is usu-
and pruritis of the face and neck. ally seen in older cats. The neoplasia may be primary