RESUMO
Hippurate-synthesizing ability was investigated in patients with jaundice with percutaneous transhepatic biliary drainage (PTBD) in relation to hepatic metabolic capacity. In 16 patients with PTBD because of obstructive jaundice and 11 patients without hepatic disease, 1.77 grams of sodium benzoate was injected and the amount of hippurate synthesized and excreted in the urine collected at 30, 60, 120 and 180 minutes was measured (hippurate test). In patients with jaundice and patients in the control group, an almost linear increase was observed in the level of urinary hippurate after benzoate loading. However, the values of the patients with jaundice at one and two hours after the benzoate loading were significantly lower than those of the patients in the control group. Serum levels of glutamate oxaloacetic transaminase, glutamate pyruvate transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, total bilirubin and direct bilirubin were significantly decreased during PTBD (p < 0.05). Bilirubin levels were closely correlated with hippurate test values (r = 0.567, p < 0.05). Values were also correlated with the period of PTBD before the hippurate test was performed (r = 0.632, p < 0.05). Recovery in hippurate synthesizing ability was observed when the total bilirubin levels decreased to less than 5 milligrams per deciliter or PTBD was maintained for more than three weeks. Because hippurate synthesis is dependent on adenosine triphosphate supply in the hepatic mitochondria, the value of the hippurate test reflects the metabolic viability of the liver in relation to energy metabolism. It is also suggested that the steady maintenance of PTBD for three weeks or more with a decrease in total bilirubin level less than 5 milligrams per deciliter is necessary for full recovery of the metabolic capacity of the jaundiced liver.