Is MRCP equivalent to ERCP for diagnosing biliary obstruction in orthotopic liver transplant recipients? A meta-analysis

Background Biliary complications are the second leading cause of morbidity and mortality in orthotopic liver transplant (OLT) recipients. Endoscopic retrograde cholangiography (ERC) is considered the diagnostic criterion standard for post-orthotopic liver transplantation biliary obstruction, but incurs significant risks. Objective To determine the diagnostic accuracy of MRCP for biliary obstruction in OLT patients. Design A systematic literature search identified studies primarily examining the utility of MRCP in detecting post-orthotopic liver transplantation biliary obstruction. A meta-analysis was then performed according to the Quality of Reporting Meta-Analyses statement. Setting Meta-analysis of 9 studies originally performed at major transplantation centers. Patients A total of 382 OLT patients with clinical suspicion of biliary obstruction. Interventions MRCP and ERCP or clinical follow-up. Main Outcome Measurements Sensitivity and specificity of MRCP for diagnosis of biliary obstruction. Results The composite sensitivity and specificity were 0.96 (95% CI, 0.92-0.98) and 0.94 (95% CI, 0.90-0.97), respectively. The positive and negative likelihood ratios were 17 (95% CI, 9.4-29.6) and 0.04 (95% CI, 0.02-0.08), respectively. Limitations All but 1 included study had significant design flaws that may have falsely increased the reported diagnostic accuracy. Conclusions The high sensitivity and specificity demonstrated in this meta-analysis suggest that MRCP is a promising test for diagnosing biliary obstruction in patients who have undergone liver transplantation. However, given the significant design flaws in most of the component studies, additional high-quality data are necessary before unequivocally recommending MRCP in this setting.