Peritoneal fluid bilirubin to serum bilirubin ratio for the diagnosis of bile leaks in orthotopic liver transplant recipients.

Background: A peritoneal fluid-to-serum bilirubin ratio (FSBR) of >5 has been shown to be accurate for the detection of bile leaks in post-cholecystectomy and trauma patients; however, there are no studies evaluating the accuracy of this threshold ratio in orthotopic liver transplant (OLT) recipients.
Methods: We performed a nested case-control analysis to determine the optimal FSBR threshold for diagnosing bile leaks in OLT recipients and the relationship between FSBR and likelihood of bile leak. Adult OLT patients undergoing ERCP for suspected bile leak were divided into 2 groups: those with cholangiographic evidence of a bile leak and those without evidence of leak. Of 57 included patients, 37 were found to have a bile leak on cholangiogram (64.9 %).
Results: We found a relationship between higher FSBR and the presence of a bile leak (OR 2.84, 95 % CI 1.37-5.88, p = 0.005). A FSBR of >3.25 produced the optimal sensitivity and specificity for identifying bile leaks in OLT recipients (area under ROC curve 0.8865, sensitivity 72.97 %, specificity 95.00 %).
Conclusions: We conclude FSBR is an easily accessible, moderately accurate test to diagnose bile leaks in liver transplant recipients. This test can inform clinical decision-making with regard to the utilization of ERCP in lower suspicion transplant recipients with a suspected bile leak.