Extrahepatic anomalies in infants with biliary atresia: results of a large prospective North American multicenter study

Abstract

Background and aims The etiology of biliary atresia (BA) is unknown. Given that patterns of anomalies might provide etiopathogenetic clues, we utilized data from the North American Childhood Liver Disease Research and Education Network to analyze patterns of anomalies in infants with BA. Methods Two hundred eighty-nine infants who were enrolled into the prospective database prior to surgery at any of 15 centers participating were evaluated. Results Group 1 was non-syndromic, isolated BA (without major malformations) (n = 242, 84 %), Group 2 was BA and at least one malformation considered major as defined by the National Birth Defects Prevention Study but without laterality defects (n = 17, 6%). Group 3 was syndromic, with laterality defects (n = 30, 10%). In the population as a whole, anomalies (either major or minor) were most prevalent in the cardiovascular (16%) and gastrointestinal (14%) systems. Group 3 patients accounted for the majority of subjects with cardiac, gastrointestinal and splenic anomalies. Group 2 subjects also frequently displayed cardiovascular (71%) and gastrointestinal (24 %) anomalies; interestingly this group had genitourinary anomalies more frequently (47%) compared to Group 3 subjects (10%). Conclusions This study identified a group of BA (Group 2) that differed from the classical syndromic and non-syndromic groups and that was defined by multiple malformations without laterality defects. Careful phenotyping of the patterns of anomalies may be critical to the interpretation of both genetic and environmental risk factors associated with BA, allowing new insight into pathogenesis and/or outcome.