Retroperitoneal Biloma due to Spontaneous Perforation of the Left Hepatic Duct.

BACKGROUND Spontaneous perforation of the bile duct in adults is very rare, particularly in cases accompanied by retroperitoneal biloma. We report a patient with retroperitoneal biloma due to a spontaneous perforation of the left hepatic duct. CASE REPORT An 82-year-old man was admitted to our institution with abdominal pain and a high fever. He had tenderness at the epi-mesogastrium. Computed tomography showed several stones in the gall bladder and common bile duct (CBD) and a few ascites. A substantial amount of fluid had collected from the dorsal stratum of the duodenum and pancreas head to the right paracolic gutter and anterior side of the right iliopsoas. Laboratory examination revealed a high inflammation score. He underwent emergent laparotomy. Biliary fluid was revealed after the mobilization of the pancreas head, duodenum, and right side of the colon. Bile duct perforation was suspected. Therefore, we exfoliated the dorsal side of the CBD to the cranial side, and intraoperative cholangiography was performed. However, the perforation site could not be detected. Cholecystectomy and choledocholithotomy were performed. A retrograde transhepatic biliary drainage tube was inserted, and primary closure of the CBD incision site was achieved. Postoperative cholangiography revealed leakage from the left hepatic duct near the caudate branch. CONCLUSIONS There are a few reports of spontaneous bile duct perforation cases in the literature, particularly on infants or children with congenital anomalies, but it is rare in adults. It usually causes bile peritonitis, although bile duct perforation should be considered in the differential diagnosis of spontaneous retroperitoneal fluid collection in adults.