Objective—To evaluate lack of encephalopathy as a positive prognostic factor for complete ligation of extrahepatic congenital portosystemic shunts in dogs.
Study Design—Retrospective analysis of case records.
Animals—Dogs with extrahepatic congenital portosystemic shunts treated at the Veterinary Medical Teaching Hospital of the College of Veterinary Medicine, Cornell University, from 1985 to 1996.
Methods—The ability to completely ligate the shunting vessel in 12 nonencephalopathic dogs was compared with that in 44 encephalopathic dogs with similar shunts.
Results—Clinical signs in the 12 nonencephalopathic dogs were related to ammonium biurate urolithiasis. All 12 dogs had single extrahepatic shunting vessels. The rate of complete ligation in the nonencephalopathic dogs was 92%, whereas the rate of complete ligation in the 44 encephalopathic dogs with single extrahepatic shunts was 59%. The ability to completely ligate the shunt in nonencephalopathic dogs was significantly better (P= .04) than in the encephalopathic dogs.
Conclusion—Lack of encephalopathy is a positive prognostic factor for complete ligation of single extrahepatic congenital portosystemic shunts.
Clinical Relevance—In most affected dogs, extrahepatic congenital portosystemic shunts in nonencephalopathic dogs can be completely ligated.