just read this on wiki (dont know how credible it is)
sounds like whats going on w. her...
Portosystemic shunt - Wikipedia, the free encyclopedia
Symptoms of congenital PSS usually appear by six months of age[1] and include failure to gain weight, vomiting, and signs of hepatic encephalopathy (a condition where toxins normally removed by the liver accumulate in the blood and impair the function of brain cells) such as seizures, depression, tremors, drooling, and head pressing. Urate bladder stones may form because of increased amounts of uric acid in circulation and excreted by the kidneys. Initial diagnosis of PSS is through laboratory bloodwork showing either elevated serum bile acids after eating or elevation of fasting blood ammonia levels, which has been shown to have a higher sensitivity and specificity than the bile acids test.[4] Rectal portal scintigraphy using 99mtechnetium pertechnetate, a technique of imaging involving detection of gamma rays emitted by radionuclides absorbed through the rectum and into the bloodstream, demonstrates the blood vessel bypassing the liver. Surgery definitively shows the shunt if it is extrahepatic.