Purpose: The aim of this study was to elucidate the epidemiology and short- and long-term results of biliary atresia in Japan analyzing the data of the Japanese Biliary Atresia Registry (JBAR).
Methods: In 1989, the Japanese Biliary Atresia Society started a nationwide registry, JBAR, to investigate all aspects of biliary atresia. A total of 1,381 patients, 863 girls, 507 boys, and 11 unknown, were registered between 1989 and 1999. JBAR includes an initial and follow-up questionnaires. Using these patients' data, the incidence, sex distribution, associated anomalies, the type of obstruction, the type of operation, and the surgical results were evaluated. The 5- and the 10-year results of 735 patients who were registered initially in or before 1994 also were analyzed.
Results: The incidence of biliary atresia was 1 in 9,640 live births. One hundred sixty-four patients (11.9%) had type I atresia of the common bile duct, 34 (2.5%) had type II atresia of the hepatic ducts, and 1,162 (84.1%) had type III atresia at the porta hepatis. Congenital associated anomalies were found in 19.6% of the patients including 33 cases associated with polysplenia. Impact of the age at operation on bile flow was not clear until 90 days of age, and after 90 days the bile flow rate worsened. The original Roux-en-Y procedure had been used in more than 50% of the patients since 1995. In 1999, 96% of the patients underwent the original Roux-en-Y procedure or the Roux-en-Y with an intestinal valve, and only 3 patients (3.5%) underwent other modifications. There were no significant differences in either the rate of disappearance of jaundice or the incidence of cholangitis among these 3 procedures. Of the 735 patients registered in or before 1994, 19 patients (2.6%) were lost to follow-up. The 5-year survival rates of patients registered in 1989, 1990, 1991, 1992, 1993, and 1994 were 62%, 64.5%, 61.3%, 59.0%, 58.7%, and 52.7% without liver transplantation (LTx), and 69.4%, 74.2%, 75.2%, 79.5%, 78%, and 78.3% with LTx, respectively. Although the overall 5-year survival rate changed from 69.4% to 78.3%, the difference was not statistically significant. According to the 10-year follow-up results of the 108 patients initially registered in 1989, 72 (66.7%) and 57 (52.8%) survived with and without the aid of LTx, respectively.
Conclusions: The overall 5- and 10-year survival rates were 75.3% (553 of 734) and 66.7% (72 of 108), respectively. In spite of the increasing number of survivors after LTx, there was no significant improvement in the 5-year survival rate. It was shown that the JBAR system was functioning well with only 19 patients lost to follow-up among the 743 patients registered from 1989 to 1994.