A two-year-old boy was presented at the hospital with prolonged fever and abdominal pain for 3 weeks His primary investigation revealed The patient has had high-grade fever and abdominal pain for 3 weeks prior to admission   The abdominal pain was confined over the right upper quadrant and epigastrium He was treated as dyspepsia without clinical improvement Physical examination revealed   Abdominal distention and right upper quadrant tenderness An ill-defined mass at RUQ  He was treated with ampicillin, gentamicin, and metronidazole intravenously, because of suspected infected choledochal cyst Imaging tests Ultrasonography demonstrated a cystic lesion, 6x4x6 cm, locating anterior to the gallbladder   Abdomen CT showed a 5x7 cm well-defined non-enhancing hypodense lesion in the left sub hepatic region, anterior-inferior to the gallbladder, containing air-fluid level (CT image attached)…