Ultrasonographic characteristics of soft tissue tumours in dogs.

OBJECTIVE: To identify and describe the ultrasonographic features of soft tissue tumours in dogs. PROCEDURE: Superficial soft tissue tumours of various histological types, including mast cell tumours (MCTs) and soft tissue sarcomas (STSs), were evaluated. Ultrasound was used to visualise internal characteristics of the tumour, including vascularity. Tumours were categorised according to size, shape, margin definition, tissue plane mobility, echogenicity, echotexture, acoustic shadowing or enhancement and vessel distribution. Objective measurements of intratumoural blood flow included velocities and maximal perfused cross-sectional area (fractional area). Logistic regression models incorporating a variety of data were used in an attempt to predict the histopathological type of tumours. RESULTS: The logistic regression model defined by the parameters echotexture, margin definition and presence of subcapsular vessels was highly predictive of MCTs (> 73%; P = 0.024). Several other trends, including a larger size for STSs and less vascularity for both MCTs and STSs, were observed, but did not reach statistical significance. CONCLUSION: This preliminary study has shown the potential diagnostic value of ultrasound in differentiating soft tissue tumours. However, at present, ultrasound cannot replace biopsy and histopathological evaluation for tumour diagnosis.

Spontaneous hepatic rupture in six cats with systemic amyloidosis.

Spontaneous hepatic rupture, secondary to the accumulation of hepatic amyloid, was diagnosed in six cats over a two-year period. Previous reports of feline hepatic amyloidosis have documented clusters of cases from breeding catteries. Most affected cats have been Siamese or a related breed and the disease is generally regarded as familial. In contrast, the cases presented here were sporadic, with relatives and other cats in the household not clinically affected. They included a Devon rex, a breed not previously reported with this condition, and a domestic shorthair. Clinical signs in three of these cases had, prior to referral, been misinterpreted as resulting from blunt trauma, immune-mediated haemolysis or a coagulopathy. Antemortem diagnostic features, including new data on the value of hepatic ultrasonography and fine-needle aspirate cytology, are reported. These cases illustrate how the course of this disease can vary between individuals and that, despite the dramatic underlying pathology, hepatic amyloidosis can present a diagnostic challenge and should be suspected in any young adult cat with consistent clinical signs, irrespective of breed or environment.

Perirenal pseudocysts in 26 cats.

OBJECTIVE: To evaluate clinical features, anatomical location, nature of pseudocyst fluid, results of surgical treatment and links with underlying renal disease in cats with perirenal pseudocysts. DESIGN: A retrospective study of 26 affected cats, including 8 treated surgically. RESULTS: Nineteen (73%) affected cats were male. The median age was 11 years. Most presented for abdominal enlargement and had varying degrees of renal dysfunction on presentation. Thirteen cats (50%) had bilateral pseudocysts. The pseudocyst fluid was a transudate or modified transudate in all cases. All surgically treated cats had subcapsular perirenal pseudocysts. Associated renal lesions were identified in all cats that had renal biopsies or detailed ultrasonographic examinations. Surgery relieved clinical signs but did not stop progression of renal disease. Cats survived a median of 9 months after surgery and survival was correlated statistically to degree of azotaemia at presentation. Percutaneous drainage of pseudocysts was ineffective in controlling long-term fluid accumulation. CONCLUSIONS: Subcapsular perirenal pseudocysts are formed in cats by accumulation of transudate between the capsule and parenchyma of the kidney as a result of underlying parenchymal disease. Pseudocyst formation can occur at variable stages of renal dysfunction. Resection of the pseudocyst wall is usually effective in eliminating signs but does not stop progression of renal disease. The prognosis for cats with pseudocyst formation is related to the degree of renal dysfunction at time of diagnosis.

Concurrent Aelurostrongylus abstrusus infection and salmonellosis in a kitten.

A 14-week-old kitten had a history of vomiting, diarrhoea and pyrexia, all of which resolved without treatment. Three weeks later the kitten developed a violent non-productive dry cough. Thoracic radiographs revealed pneumothorax and nodular alveolar disease. Aelurostrongylus abstrusus larvae and intracellular Gram-negative bacilli were seen in bronchial wash fluid and pleural exudate, and Salmonella Typhimurium was cultured from both fluids but not from faeces. Therapy included unilateral closed-tube thoracostomy, enrofloxacin and fenbendazole. Historical signs were compatible with gastrointestinal salmonellosis and secondary broncho-pneumonia. Seeding of the lungs with salmonellae may have occurred as a result of migration of A abstrusus from a gastro-intestinal tract residually infected or colonised by S Typhimurium. Alternatively, the development of lungworm infection in the cat may have activated quiescent S Typhimurium pulmonary granulomata from bacteraemia secondary to gastro-intestinal salmonellosis. Two years after diagnosis the cat was reportedly in good health.

Intestinal obstruction by trichobezoars in five cats.

Between 1997 and 1999, five domestic crossbred cats (four long haired, one short haired) presented with a palpable abdominal mass and were shown to have small intestinal trichobezoars at laparotomy or necropsy. Hair balls were associated with partial or complete intestinal obstruction and were situated in the proximal jejunum to distal ileum. In four cats obstructions were simple, while the remaining cat had a strangulating obstruction. Three of the cats were 10 years or older, and two were less than 4 years. In the three older cats abdominal neoplasia was suspected and investigations were delayed or declined in two of these cats because of a perceived poor prognosis. Predisposing factors identified in this series of cats included a long-hair coat, flea allergy dermatitis, inflammatory bowel disease and ingestion of non-digestible plant material. This report shows that the ingestion of hair is not always innocuous and that intestinal trichobezoars should be considered in the differential diagnoses of intestinal obstruction and intra-abdominal mass lesions, particularly in long-haired cats.

Quantitative ultrasonography of the liver in cats during obesity induction and dietary restriction.

A study was designed to evaluate quantitative ultrasonographic characteristics of a diffuse parenchymal disease in an experimental model of subclinical fatty infiltration of the liver using diet-induced obesity and dietary restriction in the cat. Ultrasound images of livers were quantitatively analysed by a video signal analysis technique before, during and at the end of obesity induction, and then during and following dietary restriction. Attenuation and brightness (backscatter coefficient) were correlated with hepatic lipid content obtained from the livers by surgical and ultrasound-guided percutaneous biopsy. Attenuation and backscatter increased as hepatic lipid content increased. Both attenuation and backscatter significantly correlated with the hepatic lipid content (P=0.002 and P=0.02 respectively). This model of subclinical fatty infiltration of the liver in the cat demonstrates that hepatic lipid content increases as a consequence of obesity and of severe dietary restriction. Infiltration of the liver with fat may be evaluated non-invasively using quantitative ultrasonography by the video signal analysis technique. This method of image analysis may prove useful for the evaluation of diffuse parenchymal organ disease.

Clinical and radiographic findings, treatment, and outcome in cattle with osteochondrosis: 29 cases (1986-1996).

OBJECTIVE: To summarize the radiographic and clinical findings, treatment, and outcome in cattle with osteochondrosis diagnosed radiographically. DESIGN: Retrospective case series. SAMPLE POPULATION: 29 cattle with radiographic evidence of osteochondrosis. PROCEDURES: Medical records were reviewed, and owners or referring veterinarians were contacted for outcome assessment. Data were analyzed for potential interactions between osteochondrosis classification (osteochondritis dessicans vs subchondral cyst-like lesions), clinical and radiographic findings, treatment, and outcome, using Fisher's exact test and descriptive statistics. RESULTS: Osteochondrosis was associated with young, male, purebred cattle, clinical evidence of lameness, and radiographic evidence of concurrent degenerative joint disease. Osteochondritis dissecans and subchondral cyst-like lesions had similar clinical findings and outcomes but varied significantly in their radiographic distribution among joints. Osteochondrosis often manifests clinically as a unilateral condition, but bilateral lesions were often found (88%) when limbs were radiographically examined. Cattle managed conservatively tended to be culled (within 6 months of diagnosis because of lameness) more often than those managed surgically, despite the lack of treatment bias. CLINICAL IMPLICATIONS: Osteochondrosis in cattle is often associated with lameness or degenerative joint disease. Conservative management does not result in a favorable clinical prognosis for long-term, lameness-free survival, and more studies need to be completed to evaluate the efficacy of surgical treatment of osteochondrosis in cattle.