PORTAL VEIN ANOMALY AND HEPATIC ENCEPHALOPATHY IN THREE DOGS

SUMMARY Portal vein anomaly and associated hepatic encephalopathy was diagnosed in three dogs; a 2-year-old Old English Sheep Dog, a 14-week-old Old English Sheep Dog and a 20-week-old Corgi. The common clinical changes were anorexia, vomiting, depression, weakness and ataxia. The major laboratory findings were an elevated serum alanine amino transferase activity, hypoproteinaemia, hypoalbuminaemia, prolonged retention of sulphobromophthalein, fasting and postprandial hypeoammonaemia and ammonium biurate crystalluria. Angiographic studies demonstrated the presence of a patent ductus venosus in each case. The 2 Old English Sheep Dogs were destroyed at the owners' request and the necropsy findings in each case verified the presence of a portacaval shunt and hepatic encephalopathy. The Corgi is still alive, with conservative medical management, 28 months after the onset of signs. The dog is stunted and has mild, intermittent neurological disturbances. Clinical biochemistry indicates severe hepatic insufficiency and suggests a poor long term prognosis.