Efficacy of urinary sulfated bile acids for diagnosis of bacterial cholangitis in biliary atresia

This study evaluated the efficacy of measuring urinary sulfated bile acids (USBA) for diagnosis of bacterial cholangitis in patients with biliary atresia. Eight infants with biliary atresia were recruited. The USBA level was measured when they were admitted to hospital with a fever of unknown origin. Clinical manifestations and laboratory data were reviewed. The standard USBA value for each patient (S-USBA) was defined as the level measured when they had no fever, and USBA ratio (R-USBA) was calculated as the USBA level during the febrile episode divided by the S-USBA. Then R-USBA values were compared between febrile episodes with and without cholangitis to assess the diagnostic ability of USBA. Twenty-three febrile episodes occurred in eight patients during a 15-month period. Nine episodes were diagnosed as being due to cholangitis, five were due to non-cholangitis, and nine were of undetermined origin. The R-USBA value ranged from 1.5 to 15.4 during cholangitis episodes and from 0.4 to 1.2 during non-cholangitis febrile episodes. When fever was of undetermined origin, R-USBA was found to be increased during some episodes and not in others. USBA increased immediately in patients with cholangitis. The measurement of USBA is a useful non-invasive test for cholangitis in patients with biliary atresia who had undergone Kasai's operation.