Direct bilirubin as a prognostic biomarker in enteric fistula patients complicated with sepsis: a case-control study

Objective: The objective of this study was to evaluate the predictive value of serial bilirubin determinations for mortality in enteric fistula (EF) patients complicated with sepsis. Methods: From January 1st, 2012 to January 13rd, 2013, a prospective study enrolling 162 patients was performed. Patients were divided into the survivors group (n = 119) and non-survivors group (n = 43) according to 28-day outcomes. Laboratory variables on day 0, day 3 and day 7 after admission were recorded. DB0 was defined as serum direct bilirubin (DB) value in admission, while Delta DB3 as the changes from DB3 to DB0. The definition applied to other parameters. The results were validated in an independent cohort of 116 patients. Results: Compared with survivors, non-survivors had significantly higher DB7 (23.1 +/- 10.6 vs. 11.2 +/- 1.1, P < 0.001) and procalcitonin (PCT7) (5.2 +/- 2.8 vs. 1.7 +/- 0.3 P = 0.006). ROC analysis showed that DB7 > 12.8 mu mol/L and Delta DB7 > 7.3 mu mol/L were reliable predictors (DB7: 86.4% sensitivity, 88.6% specificity (area under the curve (AUC): 0.881, P < 0.001; Delta DB7: 84.4% sensitivity, 85.1% specificity, AUC: 0.865, P < 0.001) for mortality. The combination form (DB7 > 12.8 mu mol/L + Delta PCT7 < 5.3 ng/ml) had greatest predictive value (AUC: 0.894, P < 0.001). Their predictive values were confirmed in the validation cohort. Conclusions: Serum direct bilirubin was a reliable predictor for mortality in enteric fistula patients, which should be paid close attention in the critical care.