A 7-year-old girl was admitted with a 2-week history of recurrent episodes of right upper quadrant abdominal pain. Two days prior to hospital admission, she had fever and several episodes of vomiting. There was no history of jaundice, abdominal distension, gastrointestinal bleeding, or constipation. Laboratory evaluation revealed a hemoglobin level of 10 g/dL (to convert to grams per liter, multiply by 10) and total white blood cell count of 6.4/μL (to convert to ×109/L, multiply by 0.001) (differential, 62% segmented neutrophils, 32% lymphocytes, and 6% eosinophils). The total bilirubin level was 2.4 mg/dL (to convert to micromoles per liter, multiply by 17.104). The alanine aminotransferase (132 U/L [to convert to microkatals per liter, multiply by 0.0167]), aspartate aminotransferase (126 U/L [to convert to microkatals per liter, multiply by 0.0167]), and alkaline phosphatase (1240 U/L [to convert to microkatals per liter, multiply by 0.0167]) levels were elevated. Amylase and lipase levels were normal. Transabdominal ultrasonography (US) showed a dilated common bile duct (CBD) with echogenic material and a normal gallbladder and liver. Because of the small size of the child, a 7.4-mm-diameter endobronchial US scope (EB1970; Pentax, Slough, England) was used for evaluation of the CBD from the duodenum (Figure 1 and video showing evaluation of dilated CBD).
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