Demodicosis in cats

Feline demodicosis, caused by Demodex cati, may be associated with immunosuppression, as from FeLV infection or diabetes mellitus. Clinical signs include nonpruritic alopecia, scaling, erythema and hyperpigmentation in the facial region. Local topical application of 2.5% lime sulfur solution every 10 days is usually curative in a few weeks or months.     

Neosporosis in cats

Six cats (Nos. 1-6) were inoculated intramuscularly with (1 x 10(6)) and orally (5 x 10(5)) tachyzoites of Neospora caninum. Three (Nos. 1-3) of the six cats were given 40 mg/kg methylprednisolone acetate 7 days before and on the day of inoculation with N. caninum tachyzoites, and three cats (Nos. 4-6) were not given methylprednisolone acetate. Two of the cats (cat Nos. 1 and 2) given methylprednisolone acetate died suddenly. Cat No. 1 died 8 days post-inoculation, and cat No. 2 died 16 days post-inoculation. Cat No. 3 was euthanatized 21 days post-inoculation. Cat No. 1 had lesions of gram-positive bacterial septicemia. Necrotizing encephalitis, myelitis, disseminated skeletal muscle necrosis, hepatic necrosis, interstitial pneumonia, and renal tubular necrosis were the main lesions in cat Nos. 2 and 3. The cats that were not given methylprednisolone acetate remained clinically normal except for slight weight loss in cat No. 6. All three of these cats were euthanatized 55 days post-inoculation. Mild myositis and encephalitis were noted on microscopic examination of tissues from these three cats. Neuromuscular lesions were not seen in six control cats (Nos. 7-12) not inoculated with N. caninum and euthanatized 21 or 22 days after administration of the first two doses of methylprednisolone acetate (40 mg/kg), given at a weekly interval.     

Cowpox in cats

Orthodox virus infection of domestic cats in the United Kingdom was first reported in 1978. Outbreaks of a disease considered to be due to cowpox (orthopox) infection had been reported in a number of species of zoo animals in Europe between 1971 and 1977 and a serious outbreak occurred among cheetahs in a United Kingdom zoo. In this species the clinical signs were ülcerating and crusted skin lesions, in some cases complicated by respiratory signs and death. An increasing number of cases of pox infection of domestic cats has been reported in Great Britain. Affected animals have shown ulcerating and crusted skin lesions particularly of the head and limbs; systemic illness was uncommon. Immunologically compromised cats, ie, FeLV positive or those receiving corticosteroid of megestrol acetate therapy, were found to be more likely to show extensive or generalised pox lesions. The source of infection is thought to be small wild mammals, ie, voles, acting as a reservoir of virus, which are preyed upon by domestic cats. Feline orthopox virus infection is a zoonosis. Transmission of the disease from affected cats to incontact owners has been reported from Great Britain and the continent of Europe. The differential diagnosis of the condition in cats includes those skin disorders commonly treated with steroidal anti-inflammatory preparations. Definite diagnosis is important as these drugs are contraindicated in viral infections. Confirmation of diagnosis may be by virus isolation and serology. Histological examination of skin biopsy specimens is also helpful. Whether or not the causal agent of this disease should be referred to as cowpox virus or feline orthopox virus continues to be a matter of debate.     

Angiosarcoma in cats

In a survey of 3145 feline necropsies at The Animal Medical Centre, eighteen cases of haemangiosarcoma and one case of lymphangiosarcoma were diagnosed. The haemangiosarcomas were primarily located in the spleen (four), liver (six), mesentery (four), mediastinum (three) and the lungs (one). The lymphangiosarcoma was seen in the skin and subcutaneous tissue of the abdominal wall and thighs. The clinical, macroscopic, and microscopic features of these tumours have been described. The most common clinical signs in the case of haemangiosarcoma were due to the rupture of the primary or metastatic neoplasms (70%). Metastases wese observed in 67% of the cases. Three main histological types (1, cavernous; 2, solid; and 3, capillaries separated by stroma) were observed, although mixtures of more than one histological type were seen in any one particular tumour. Rare cases of pulmonary haemangiosarcoma and lymphangiosarcoma in the cat have also been described.     

Osteopetrosis in cats

Osteopetrosis was found in two adult cats, radiographically characterised by a ‘marble bone’ appearance of the axial skeleton and of the subchondral bone of all joints, and endosteal thickening of the cortex of long bones. Computer tomography and histological assessment revealed massive endosteal lamellar bone formation. Bone resorption was still apparent, though only atypical mononuclear osteoclasts were seen. Histological findings support the assumption that the disorder was acquired. Severe anaemia was found in one cat. In the other, no clinical abnormalities were present. The condition appears to be different from feline leukaemia virus-induced medullary osteosclerosis described by Hoover and Kociba (1974).