Background/Purpose: Late-onset cholangitis is an uncommon complication after the Kasai operation for biliary atresia.Experience with 3 recent patients illustrates appropriate management.Methods: Retrospective review of patients with late unexplained deterioration in liver function attributed to cholangitis.All underwent quantitative radioisotope hepatobiliary scans to identify the Roux loop obstruction and confirm post operative resolution. The role of percutaneous transhepatic cholangiography and computed tomography scanning was reviewed.Results: Three patients aged 8, 13, and 17 years were identified. All 3 had had a successful Kasai portoenterostomy for type 3 biliary atresia and presented after several virtually trouble-free years with late-onset cholangitis. The radioisotope scans in all 3 patients showed poor tracer uptake by the liver and pooling of the radioisotope at the porta hepatis. Laparotomy confirmed a proximal Roux loop obstruction at the level of the mesocolic window in all. This required mobilization and adhesiolysis and, in 1, correction of an actual stenosis with in the wall of the intestine at this level. All patients had normalization of their liver function postoperatively. All are now well and anicteric at a follow-up of 6 to 12 months. Conclusions:Long-term survivors of the Kasai portoenterostomy for biliaryatresia with immediate deterioration in liver function warrant investigation for possible Roux loop obstruction. Resolution of the obstruction allows preservation of their native liver. Background / Purpose: Late-onset cholangitis is an uncommon complication after the Kasai operation for biliary atresia. Experience with 3 recent patients illustrates appropriate management. Methods: Retrospective review of patients with late unexplained deterioration in liver function attributed to cholangitis. All underwent quantitative radioisotope The role of percutaneous transhepatic cholangiography and computed tomography was reviewed. Results: Three patients aged 8, 13, and 17 years were identified. All 3 had a successful Kasai portoenterostomy for type 3 biliary atresia and presented after several virtually trouble-free years with late-onset cholangitis. The radioisotope scans in all 3 patients showed poor tracer uptake by the liver and pooling of the radioisotope at the porta hepatis. Laparotomy confirmed a proximal Roux loop obstruction at the level of the mesocolic window i n all. This required mobilization and adhesiolysis and, in 1, correction of an actual stenosis with in the wall of the intestine at this level. All patients had normalization of their liver function postoperatively. All are now well and anicteric at a follow-up of 6 to 12 months. Conclusions: Long-term survivors of the Kasai portoenterostomy for biliary atresia with immediate deterioration in liver function warrant investigation for possible Roux loop obstruction. Resolution of the obstruction allows preservation of their native liver.