Diagnostic dilemma of cystic biliary atresia: A series of two cases and brief review of the diagnostic modalities.

Cystic biliary atresia (CBA) is a rare variant of biliary atresia that closely resembles choledochal cyst (CC), complicating diagnosis and potentially delaying critical surgical intervention. We report two cases of CBA that were difficult to diagnose. Case 1 involved a 32+2-week-old infant with ABO incompatibility and conjugated hyperbilirubinemia. Ultrasound suggested CC, but magnetic resonance cholangiopancreatography (MRCP) indicated CBA, confirmed by intraoperative cholangiogram. The infant underwent Kasai hepatoportoenterostomy (KHPE) and is now 2 years old with normal liver function. Case 2 involved a 17-day-old infant with hyperbilirubinemia and pigmented stools. Ultrasound and MRCP suggested CC or CBA, confirmed as CBA through intraoperative cholangiogram. The infant underwent KHPE but later required liver transplantation due to cirrhosis and is now 2 years old with normal liver function. Early diagnosis and timely surgical intervention are crucial for managing CBA, with KHPE being the treatment of choice if performed within 30-45 days of life.