A 99-day-old boy was admitted to our hospital because of “abdominal B-ultrasound indicating gallbladder sludge for 2 months.” The infant was diagnosed with left nephroblastoma at birth. In the second cycle of chemotherapy, abdominal B-ultrasound indicated a low echo area in the gallbladder, and the diagnosis of gallbladder sludge was accordingly considered. The child exhibited jaundice and a progressive elevation in gamma-glutamyl transferase (γ-GT). He was transferred to our hospital for further treatment. The physical examination on admission revealed the following: temperature: 36.7°C, pulse rate: 154 times/min, respiratory rate: 36 times/min, blood pressure: 90/62 mmHg, percutaneous oxygen saturation: 97%, and weight: 7.5 kg. Mild jaundice was noted. He had no rash or blood spots on his skin. The heart and lung examinations were unremarkable. His abdomen was flat and non-tender and had no rebound tenderness. No mass was palpated. Murphy's sign was negative. The laboratory results revealed the following (Table 1): total bilirubin (TB) 73.4 μmol/L, conjugated bilirubin (CB): 55.9 μ/L, alanine aminotransferase (ALT): 84 U/L, aspartate aminotransferase (AST): 103 U/L, γ-GT: 2,189 U/L, alkaline phosphatase (ALP): 607 U/L, blood amylase: 3 U/L, white blood cells (WBCs): 10.9 × l0⁹/L, percentage of neutrophils: 8.9%, and percentage of lymphocytes: 81.5%. Blood coagulation function and routine urine and stool values were normal. B-ultrasound was repeated and showed that the diameter of the upper segment of the CBD was 0.8 cm. A hypoechoic mass was noted in the lower CBD. The CBD and intrahepatic bile duct were dilated.

After full communication and preoperative examinations were completed, the infant underwent ERCP. He was placed in the prone position and underwent ERCP under general anesthesia with intubation. An Olympus JF240 duodenal endoscope was used. The duodenal papilla appeared and had a granular, fluffy opening. An Olympus triple-lumen needle knife and a 0.025-inch Loach guide wire were used to achieve successful selective biliary cannulation. The bile sample obtained during backsuction was cloudy and dark. Under fluoroscopy, cholangiography was performed from the upper to lower segment of the CBD and showed dilation of the CBD (1.1 cm in diameter). Multiple contrast filling defects were observed in the CBD. At the 12 o'clock site of the bile duct, a small, 0.2 cm longitudinal incision was made in the papilla. No bleeding was observed at the cutting edge. A grasping basket was used to remove multiple black stones. Finally, a stone retrieval balloon was used to remove the stones in the bile duct. A 6 Fr straight-tip nasobiliary drainage catheter was placed at the end of the ERCP (Figures 1A–F). The endotracheal tube was removed upon awakening. The patient had stable vital signs and was returned to the ward. An laboratory results were repeated 72 h after ERCP and showed the following (Table 1): TB: 28.3 μmol/L, CB: 23.7 μmol/L, ALT: 33 U/L, AST: 31 U/L, γ-GT: 1,033 U/L, AKP: 201 U/L, blood amylase: 3 U/L, WBCs: 9.8 × l0⁹/L, neutrophils: 24.1%, and lymphocytes: 62.3%. The jaundice markedly improved. He was energetic and had acceptable food intake. Four days after ERCP, cholangiography was performed via a nasobiliary catheter and showed smooth draining of the contrast agent and no residual stones in the bile duct. Then, the nasobiliary catheter was removed. A liver function examination was repeated 1 week after ERCP; the profile had returned to normal. The patient was discharged.