Congenital biliary malformations encompass a spectrum of structural defects in the extra- and intrahepatic bile ducts. The phenotypic expression is determined by the embryologic stage at which development is arrested and by the subsequent impairment of bile flow. Three cardinal symptom complexes dominate the clinical picture: cholestatic jaundice, recurrent cholangitis, and secondary hepatic dysfunction.

1. Cholestatic Jaundice
   Conjugated hyperbilirubinemia is the earliest and most consistent finding. In neonates it is usually recognized after the physiological jaundice window (>2 weeks of life) and is marked by progressive acholic stools and dark urine reflecting absent intra-intestinal bilirubin. In older children jaundice may fluctuate, often precipitated by intercurrent infection or intermittent cystic distension.
2. Abdominal Pain and Palpable Mass
   Dilation of the extrahepatic duct (choledochal cyst) produces right-upper-quadrant discomfort or colicky pain. A discrete, non-tender, cystic mass is palpable in up to 60 % of affected infants. Sudden enlargement may herald complete obstruction or intracystic hemorrhage.
3. Cholangitis and Systemic Sepsis
   Stagnant bile predisposes to bacterial ascent, presenting as fever, rigors, and elevated serum C-reactive protein. Repeated episodes accelerate periportal fibrosis and may precipitate acute-on-chronic liver failure.
4. Growth Failure and Fat-Soluble Vitamin Deficiency
   Chronic cholestasis impairs enterohepatic circulation of bile acids, leading to steatorrhea, hypoalbuminemia, and deficiencies of vitamins A, D, E, and K. Manifestations include rachitic rosary, coagulopathy, and failure to thrive despite adequate caloric intake.
5. Portal Hypertension and Cirrhosis
   Untreated malformations evolve toward biliary cirrhosis, with subsequent splenomegaly, thrombocytopenia, and variceal bleeding. Hepatopulmonary syndrome with digital clubbing and exertional dyspnea may supervene, mandating transplant evaluation.
6. Pancreaticobiliary Reflux–Associated Pancreatitis
   Anomalous pancreaticobiliary junction permits activation of pancreatic enzymes within the common channel, producing episodic hyperamylasemia and acute pancreatitis.
7. Miscellaneous Anomalies
   Gall-bladder agenesis is usually silent, yet concomitant ductal atresia can reproduce the full cholestatic phenotype. Intrahepatic gall-bladder predisposes to cholelithiasis and recurrent biliary colic.