Diagnosis and management of biliary cystic malformations in neonates

Recent advances in ultrasonography have made it possible to identify biliary atresia (BA) and choledochal cyst (CC) with biliary cystic malformations (BCM) both prenatally and neonatally. The early differential diagnosis between BA and CC is extremely important because operations must be performed as soon as possible before the livers of BA patients advance to an irreversible cirrhotic stage. The aim of this study was to differentiate patients with BCM and to determine the best course of management in the neonatal period.

The medical records of patients that were diagnosed with BCM by a prenatal or neonatal ultrasound between 1997 and 2008 were reviewed. We retrospectively divided the BCM patients into the BA and CC groups and then compared the results of ultrasound, computed tomography, and laboratory tests between the 2 groups.

Ten patients were enrolled in the study. The median age at the time of corrective surgery was 74 days (range, 24-206 days). All of the BA cases received an operation by the time they were 60 days old. In the BA group (5 patients), the mean cyst size was 15 mm, the mean direct bilirubin (D-Bil) was 3.3 mg/dL, and the mean total bile acid (TBA) was 138.1 µmol/L at 30 days of age, whereas in the CC group (5 patients), cyst size, D-Bil, and TBA were 40 mm, 0.9 mg/dL, and 46.9 µmol/L, respectively. These differences between the 2 groups were statistically significant. All of the patients with CC successfully cleared their jaundice, whereas 4 patients with BA subsequently required liver transplantation for liver failure. In our study, all patients with BCM less than 21 mm, D-Bil greater than 2.5 mg/dL, and TBA greater than 111 µmol/L in the neonatal period were diagnosed with BA.

Our data suggested that patients with BCM smaller than 21 mm, D-Bil higher than 2.5 mg/dL, and TBA higher than 111 µmol/L in the neonatal period were more likely to have BA than CC. This potential diagnosis should be surgically examined and corrected as soon as possible.