A six months old domestic short hair cat was presented at small animal clinic after a period of severe anorexia and skin lesions. The animal was fully clinically examined, which also included radiography and laboratory examinations. In clinical examination the animal was febrile and acute moist dermatitis was seen, especially in prneaum, around the anal sphincter. Sever pododermatitis, paronychia and hyperkeratosis of footpads induced lameness in animal. Impetigo with crust formation on marginal surface of pinea and nasal planum was seen too. Several skin biopsies were obtained from lesions. There was no abnormality in thoracic and abdominal radiographs. Results of complete blood count indicated leukocytosis and neutrophilia. There was no biochemical abnormality except the imbalance of the albomin/glubolin ratio. The level of globulin was very high (5.6 gr/dl). Electrophoresis showed that level of β2 globulin (1.4 gr/dl) and γ globulin (3.4gr/dl) was increased. From the pus of interdigital fistulas on bacteriological examination, beta hemolytic Streptococcus, pasteurella multocida and pseudomonas aeruginosa were isolated. Histopathological findings are as follow: Acanthosis and hyperkeratosis was obvious. Basement membrane had minimal change but invasion of microcarcinomatous islets of epidermal cells was occurred. These cells possessed of normal shape and orientation and did not show pleomorphism, mitotic figures and or other indices of malignancy. The epidermal cells in the dermis formed horn pearls and the thickened, downward growing epidermis forms a crypt, which eventually becomes a multiloculated cyst crowded with keratin.

Although there is no report of keratoacanthoma occurrence in cats and in veterinary medicine this tumor has been described only in dogs, results of clinical examination besides pathological finding confirm the occurrence of Keratoacanthoma in this case(1). Because often an epithelial pore that furnishing a direct connection between cavity and epidermal surface is present, Inflammatory reactions can be encountered in more than 90% of the tumors, especially in ruptured ones. Secondary bacterial infections that cause acute moist dermatitis and impetigo come off for this reason. In animal tumor, versus human, lake of tumor elevation in early stages, deeper origin in the skin and multiplicity caused surgical techniques unsuccessful and conservative treatment was suggested(2). Thus To improve the clinical status of animal and control of secondary bacterial infections, syrup Amoxyclav were used for two weeks. Conservative Treatment by daily washing of lesions with chlorhexidine solution (0.2%) and topical gel of Benzyl peroxide (5%)was recommended and for decrease of sever skin inflammation, prednisolone tablets (5 mg) in taper dosage was used for 4 months. After this period the lesions were cured and there was no relapse of disease in length of monitoring of animal. Keratoacanthoma in animals as in man, could be a self -limiting disease, and proper control of secondary bacterial infection can cured the disease(2).

References

1.  Rudolph, R.; et al., (1977) Intracutaneous cornifying epithelioma ("keratoacanthoma") of dogs and keratoacanthoma of man, Cornell Veterinarian,V 67 (2), p. 254-264.

2.  Rudolph, R., (1983) Spontaneous keratoacanthoma--animal model for the tumour of man? Deutsche Tierarztliche Wochenschrift, V 90 (9), p.349-352.