The microscopic examination of bile in patients with biliary pain and negative imaging tests.

We describe a 5-yr retrospective analysis of the accuracy of the microscopic examination of bile in the detection of biliary tract disease in patients with episodic upper abdominal pain who had negative imaging procedures. In 182 patients, 189 studies of bile were performed using duodenal intubation and sincalide stimulation for gallbladder contraction. The presence of cholesterol crystals, leukocytes (greater than or equal to 5/hpf) or the absence of "B" bile constituted a "positive" study. Bilirubinate sludge alone, was defined as "suspicious." Eighty-three patients underwent cholecystectomy. Among the acalculous patients who underwent cholecystectomy, 28/28 with bilirubinate sludge had symptomatic improvement as compared with the negative group of which only five of 10 improved (p less than 0.005). The sensitivity of this test for the presence of gallstones in these imaging-negative patients was 87%, while the specificity was 16%. We conclude that a single microscopic examination of bile cannot accurately predict the pathological findings or the presence of gallstones in image-negative patients with biliary pain. The presence of bilirubinate sludge may predict symptomatic improvement in those patients with acalculous gallbladder disease undergoing cholecystectomy.