Definition and Classifications of Biliary Atresia

In the late 1950s, Professor Kasai from Tohoku University in Japan noted that bile flow from the porta hepatis was possible after excision of the entire fibrotic extrahepatic biliary tree. The prognosis of these patients is related to the differences in the site of obstruction and most classifications are based on these, using the macroscopic findings and a direct cholangiogram. There are many different types of classification for biliary atresia (BA) in the literature. There are five recent large-scale reports that refer to disease types, including those from Japan, the United States, the United Kingdom, the Netherlands, and France. We introduce these five large-scale reports using the Japanese Biliary Atresia Society (JBAS) classification and compare their long-term native liver outcomes. The age at surgery is also important for BA. The overall average age at surgery in Japan was 66.5 days. The group of patients who underwent surgery less than 30 days of age (the neonatal period) showed the best jaundice clearance rate (71.9%). Finally, we introduce a severity classification because, in Japan, the cost of treatment is supported by publicly funded medical care.