Presence of white bile associated with lower survival in malignant biliary obstruction

Objective: The chemical composition and clinical significance of white bile In patients with malignant biliary obstruction were evaluated in a prospective study. Methods: Consecutive patients (January 1996 through December 1997) with inoperable malignant biliary obstruction underwent endoscopic placement of 10F straight, plastic biliary stents. Bile was aspirated during the endoscopic procedure. Patients were divided into 2 groups: those with white and those with yellow bile. The chemical composition of bile was analyzed. Levels of bile acids in the serum and bile (11 samples) were estimated by high-performance thin-layer chromatography. The groups were compared for decremental fall in bilirubin (b value), cholangitis after stent insertion, and survival. Results: Thirty-five patients (15 men, 20 women; mean age 54 years) underwent endoscopic drainage for malignant obstruction (29 hilar, 6 distal bile duct). Eighteen patients had white bile. Refractory jaundice (b > -0.025) was seen in 9 (50%) patients with white bile compared with 3 (17.6%) with yellow bile; mean difference -42.2 (95% CI [-62.4, -22.0]) and -45.7 (95% CI [-72.0, -19.4]), respectively. The bilirubin (0.48 mg/L) and bile acid (15.6 mmol/L) concentrations in white bile were significantly less than bilirubin (42.7 mg/L) and bile acid (61.3 mmol/L) concentrations in yellow bile; mean difference -42.2 (95% CI [-62.4, -22.0]) and mean difference -45.7 (95% Cl [-72.0, -19.4]), respectively. Cholangitis developed in 66.6% of patients with white bile compared with 35% of those with yellow bile (OR 3.67: 95% CI [0.74, 19.25]). Kaplan-Meier curves showed that median survival (interquartile range) was shorter in patients with white bile (35 [23-60] versus 77 [35-220] days) (p = 0.004, log rank test), which was significant even after adjusting for potential confounders with Cox proportional hazards regression. Conclusion: White bile is largely devoid of bilirubin and bile acids. The presence of white bile was associated with significantly worse survival in patients with malignant biliary obstruction.