Page 1123 - Problem-Based Feline Medicine

53 – THE CAT WITH PAW OR PAD PROBLEMS 1115

Chronic lesions develop nodules, pigment changes Prognosis and prevention
(dark or pale patches), and alopecia.
Good control of the problem is possible if the cat can
Footpads may be affected with swelling, scales or be kept away from biting insects, or will tolerate insect
crusts, hyperkeratosis, fissures and pigment changes. repellent.

However, lesions may increase with severity over the
Diagnosis years if exposure cannot be controlled.

Seasonal occurrence is evident coinciding with mos-
PLASMA CELL PODODERMATITIS*
quito or midge season in cats allowed outdoors.
Tentative diagnosis can be confirmed by keeping the Classical signs
cat indoors or hospitalized for 5 days and demon-
● Swollen, very soft footpads, generally non-
strating great improvement of lesions.
painful.
Biopsy and obtain small specimens (4-mm biopsy punch) ● Normal pad symmetry.
carefully, as the ears and nose bleed easily and readily
show scars. Histopathological changes are similar to those
Pathogenesis
of cats with atopy, food and flea bite hypersensitivity.
Plasma cell pododermatitis is a rare skin disease
affecting the footpads.
Differential diagnosis
The cause is unknown, but is thought to be immune-
Food allergy commonly results in pruritis of the face,
mediated or allergic.
head, pinnae and neck, in contrast to just the nose
and/or ears affected with insect hypersensitivity. One study found 50% of cases to be feline immuno-
Lesions are usually asymmetrical and very excoriated. deficiency virus-positive.
Non-seasonal occurrence, and does not respond to the
indoor confinement trial, but responds to an elimination Clinical signs
dietary trial.
Typically, the footpads are swollen, very soft and
Autoimmune diseases such as pemphigus foliaceus/ fluctuant (mushy). Usually the larger metacarpal and
erythematosus and discoid lupus erythematosus typi- metatarsal pads are the ones affected.
cally also have a symmetric pattern, but usually there is
Normal pad symmetry is not disturbed by the swelling,
extensive crusting and exudation of head and body.
but the stretching of the skin over the swollen pad
Depression and anorexia are often present. Pruritis is
results in a white, silvery, cross-hatched appearance.
variable.
Lesions involve one or more feet.
Normally, the lesions are non-painful and the cat is
Treatment
not lame, although cases of cats limping on the affected
Keep the cat indoors at the times of greatest insect feet have been reported.
activity, usually early morning and dusk.
The pad may become ulcerated, and drain hemor-
Topical insect repellents applied to the affected area. rhagic fluid.
Try a variety, as not many are well tolerated by cats;
Some cats also have plasma cell stomatitis, immune-
ointments or creams are best tolerated.
mediated glomerulonephritis or renal amyloidosis.
Petroleum jelly smeared on the ear tips and nose has
also been used successfully. Diagnosis

Oral prednisolone (0.5–2 mg/kg on alternate days) or Fine-needle aspirate of the lesion contains large num-
injectable glucocorticoids (repositol methyl pred- bers of uniform plasma cells with a few neutrophils and
nisolone acetate, 20–40 mg/cat subcutaneously). lymphocytes.