Background/aims: Abnormal liver chemistry tests are a hallmark of common bile duct (CBD) stones. There is little information, however, on the prevalence of and predictors for normal liver chemistry tests in such patients.
Methods: Over an 11-year period, all patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) at our Center were prospectively identified. Patients in this study were those with CBD stones found at ERCP and where the indication for ERCP was CBD stones seen on imaging studies or when CBD stones were highly suspected based upon clinical presentation and radiographic and laboratory findings. Liver chemistry tests were recorded from those taken at the time of initial presentation as well as the time closest to ERCP.
Results: Of a total of 5,133 patients undergoing ERCP during the study period, the indication was suspicion for CBD stones or for radiographically identified CBD stones in 476 and 593, respectively, with 115 patients having both indications. Of these 1184 patients, 765 had CBD stones of whom 541 had liver tests. Of these 541, 29 patients (5.4%) were found to consistently have normal liver chemistry tests. Multivariate analysis identified two factors predictive of normal liver tests including age >55 years and the presence of abdominal pain.
Conclusions: Although rare, liver tests can be normal in patients with CBD stones. Patients most likely to have normal liver tests included older patients and those with abdominal pain.