Clinical and clinicopathologic abnormalities in young dogs with acquired and congenital portosystemic shunts: 93 cases (2003-2008).

OBJECTIVE: To determine whether clinical and clinicopathologic data could assist differentiation of congenital portosystemic shunts (CPSSs) from acquired portosystemic shunts (APSSs) in young dogs. DESIGN: Retrospective case series. ANIMALS: Dogs < 30 months of age with CPSSs (n = 62) or APSSs (31). PROCEDURES: Medical records from 3 referral centers identified 31 dogs with APSSs and 62 dogs with CPSSs diagnosed from July 2003 to July 2008. Signalment, clinical signs, physical examination, and clinicopathological data were recorded, and statistical analyses were performed to determine differences between groups. RESULTS: Univariable analysis showed APSS patients were older, heavier, and in poorer body condition, compared with CPSS patients. In CPSS patients, diarrhea was less prevalent, and neurologic signs were more prevalent. Ascites was more prevalent in APSS (Fisher exact test; OR, 50.2; 95% confidence interval [CI], 6.2 to 409.7), with no significant difference in albumin concentration between groups. The logistic regression model used to assess clinicopathological parameters showed lower Hct (OR, 1.42 × 10(-12); 95% CI, 1.42 × 10(-17) to 4.0 × 10(-6)), higher mean corpuscular volume (OR, 1.27; 95% CI, 1.08 to 1.50), and higher alanine aminotransferase concentrations (OR, 1.005; 95% CI, 1.001 to 1.009) were more likely in APSS patients. CONCLUSIONS AND CLINICAL RELEVANCE: Several clinicopathologic differences between dogs with congenital and acquired shunts were identified; however, assessed alone, these would be unlikely to enable differentiation between the 2 conditions. Awareness of the rarity of ascites in CPSS cases should prompt recognition of a likely diagnosis of APSS, allowing the veterinarian to target further diagnostics and counsel the owner appropriately.

Underlying diseases in dogs referred to a veterinary teaching hospital because of dyspnea: 229 cases (2003-2007).

OBJECTIVE: To identify the most frequent underlying diseases in dogs examined because of dyspnea and determine whether signalment, clinical signs, and duration of clinical signs might help guide assessment of the underlying condition and prognosis. DESIGN: Retrospective case series. ANIMALS: 229 dogs with dyspnea. PROCEDURES: Case records of dogs referred for dyspnea were reviewed and grouped according to location or etiology (upper airway, lower respiratory tract, pleural space, cardiac diseases, or obesity and stress). Signalment, clinical signs at initial examination, treatment, and survival time were analyzed. RESULTS: Upper airway (n = 74 [32%]) and lower respiratory tract (76 [33%]) disease were the most common diagnoses, followed by pleural space (44 [19%]) and cardiac (27 [12%]) diseases. Dogs with upper airway and pleural space disease were significantly younger than dogs with lower respiratory tract and cardiac diseases. Dogs with lower respiratory tract and associated systemic diseases were significantly less likely to be discharged from the hospital. Dogs with diseases that were treated surgically had a significantly better outcome than did medically treated patients, which were significantly more likely to be examined on an emergency basis with short duration of clinical signs. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs examined because of dyspnea, young dogs may be examined more frequently with breed-associated upper respiratory tract obstruction or pleural space disease after trauma, whereas older dogs may be seen more commonly with progressive lower respiratory tract or acquired cardiac diseases. Nontraumatic acute onset dyspnea is often associated with a poor prognosis, but stabilization, especially in patients with cardiac disease, is possible. Obesity can be an important contributing or exacerbating factor in dyspneic dogs.

Biliothorax in a Siamese cat.

A 2-year-old male neutered cat presented for further investigation of biliothorax. The cat was initially treated for pyothorax, including bilateral chest drains for lavage of the pleural space. Five days later, the pleural effusion turned clear-yellow and had a bilirubin concentration of 427 µmol/l compared to the serum bilirubin concentration of 15 µmol/l. Exploratory surgery revealed a 2mm tear in the diaphragm, with a corresponding 2mm defect in the diaphragmatic surface of the gall bladder, creating a fistula between the gall bladder and the pleural cavity. The defects were repaired routinely and the cat made a full recovery. It was suspected that the tears had been created at the time of the thoracostomy tube placement. Biliothorax has not been described before in a cat, and appears to be a rare complication following thoracostomy tube placement.

Use of recombinant human interferon alpha-2a in the management of a dog with epitheliotropic lymphoma.

An 8-year-old, mixed-breed dog with preputial epitheliotropic lymphoma was initially treated with cyclophosphamide, vincristine, and prednisolone. A short-term partial response was followed by disease progression after 4 weeks. Recombinant human interferon alpha-2a was administered starting at week 7. The interferon therapy resulted in rapid resolution of clinical signs and a 10-week disease-free interval. The lymphoma recurred at 17 weeks and did not respond to rescue chemotherapy. Additional oral lesions were treated with localized radiotherapy followed by increased dosages of interferon. This additional interferon treatment resulted in another 12 weeks of stable disease.

Efficacy of en bloc ligation of the thoracic duct: descriptive study in 14 dogs.

OBJECTIVE: To assess whether en bloc ligation of all caudal mediastinal tissue between the aorta and thoracic vertebrae will occlude all branches of the thoracic duct. STUDY DESIGN: Descriptive study. ANIMALS: Canine cadavers (n=15). METHODS: The cisterna chyli was approached through a right paralumbar abdominal incision and cannulated. A right 10th intercostal thoracotomy was performed and the tissue of the caudal mediastinum dorsal to the aorta and ventral to the thoracic vertebrae was ligated. Radio-opaque contrast material was injected into the cisterna chyli during fluoroscopic imaging of the thorax and cranial abdomen. Still images were obtained before and after contrast injection and a subtraction image produced. Gray values were measured from these images, cranial and caudal to the ligature site. RESULTS: Cannulation of the cisterna chyli in 1 cadaver was impossible and it was, therefore, excluded. In 13 (93%) cadavers contrast material did not pass cranial to the ligature site. In 1 cadaver, an intact thoracic duct was identified on lymphangiography outside the en bloc ligation. CONCLUSION: En bloc ligation of the caudal mediastinal tissue dorsal to the aorta was successful in preventing opacification with contrast material of all branches of the thoracic duct in 93% of cadavers. CLINICAL RELEVANCE: En bloc ligation is successful in 93% of cadavers and reduces the operative time compared with techniques requiring some type of mesenteric lymphangiography to aid identification of the thoracic duct.