Portosystemic shunts in cats--evaluation of six cases and a review of the literature.

The objective of this study was to give a recent review of the literature of portosystemic shunt (PSS) in cats and to describe a case series of 6 cats diagnosed with PSS. Cats diagnosed with a PSS between 1997 and 2006 were reviewed with a focus on history, clinical signs, laboratory findings, imaging techniques, and outcome. Among 12,438 analysed cats, six cats were found with confirmed PSS (one portocaval, two intrahepatic, and three portoazygos shunts) leading to a prevalence of PSS in cats of 4.8/10,000 (0.048%) when compared to the clinic population. Three of the cats were purebred; four were male and two female. Median age at time of diagnosis was four months. All cats showed signs of hepatoencephalopathy and elevated fasted serum bile acids. Elevated fasted ammonia levels were found in five of six cats. Abdominal ultrasonography showed the shunting vessel in four of six cats. Three of four cats in which the shunt was surgically attenuated had a good to excellent outcome (follow up of 65 months). In conclusion PSS are rare in cats. Affected cats may have an excellent long term outcome with surgery.