title: Useful predictors of bile duct stones in patients undergoing laparoscopic cholecystectomy. McGill Gallstone Treatment Group.
abstract: OBJECTIVE
  The authors determined the most useful predictors of common bile duct (CBD) stones as diagnosed by endoscopic retrograde cholangiopancreatography (ERCP) in patients who underwent laparoscopic cholecystectomy (LC).
  
  
  METHODS
  Prospective and retrospective collection of historical, biochemical and ultrasonographic data was used. Receiver operating characteristics curve analysis was used to determine optimal biochemical cut-off values. Multivariate analysis using logistic regression with generation of the best model identifying independent predictors of CBD stones also was employed. Prospective validation of the model was performed on an independent group of patients.
  
  
  RESULTS
  Endoscopic retrograde cholangiopancreatographies were performed before LC in 106 patients, and after LC in 33. Only four of ten clinical variables evaluated independently predicted the presence of CBD stones. The optimal model predicted a 94% probability of CBD stones in a patient older than 55 years of age who presented with an elevated bilirubin (over 30 mumol/L) and positive ultrasound findings (a dilated CBD, and a CBD stone seen on ultrasound). This model was validated prospectively in a subsequent series of 49 patients in which the probability of CBD stone was only 8% when all four predictors were absent.
  
  
  CONCLUSIONS
  The identified independent clinical predictors of a CBD stone helps select a population of symptomatic gallstone bearers who benefit most from cholangiographic assessment.
authors.affiliation: Division of Gastroenterology, McGill University, Montreal, Quebec, Canada.
authors.forename: A N
authors.initials: AN
authors.lastname: Barkun
authors.forename: J S
authors.initials: JS
authors.lastname: Barkun
authors.forename: G M
authors.initials: GM
authors.lastname: Fried
authors.forename: G
authors.initials: G
authors.lastname: Ghitulescu
authors.forename: O
authors.initials: O
authors.lastname: Steinmetz
authors.forename: C
authors.initials: C
authors.lastname: Pham
authors.forename: J L
authors.initials: JL
authors.lastname: Meakins
authors.forename: C A
authors.initials: CA
authors.lastname: Goresky
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000469:Alkaline Phosphatase / Q000097:blood; D000681:Amylases / Q000097:blood; D001663:Bilirubin / Q000097:blood; D002760:Cholangiopancreatography, Endoscopic Retrograde; D017081:Cholecystectomy, Laparoscopic; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D042882:Gallstones / Q000097:blood / Q000175:diagnosis* / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011446:Prospective Studies; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D005723:gamma-Glutamyltransferase; D000469:Alkaline Phosphatase; D000681:Amylases; D001663:Bilirubin