**3. Microlithiasis**

Microlithiasis/biliary sludge is a controversial etiology for acute pancreatitis. Biliary sludge is detected in 75% of the patients with recurrent idiopathic acute

pancreatitis [16, 17]. Abdominal ultrasound has low sensitivity in diagnosis of biliary sludge. Bile analysis with microscopic examination for cholesterol crystals is the gold standard for diagnosing biliary sludge with however a sensitivity of 66% [18].

The bile for analysis can be obtained directly through common bile duct aspiration at ERCP or by duodenal aspiration of bile after cholecystokinin stimulation. EUS can also be utilized in diagnosis of microlithiasis/biliary sludge with a higher sensitivity and also applicability in evaluating other causes of idiopathic acute pancreatitis [18]. ERCP should be done 4–6 weeks after the initial presentation when the pancreatitis has resolved and if microlithiasis is detected, cholecystectomy or biliary sphincterotomy can be considered as management options depending on the patient's surgical risk [19].
