Serum bile acids in patients with hepatopulmonary syndrome

Background Hepatopulmonary syndrome (HPS) occurs in 20 - 30 % of patients with cirrhosis and is associated with increased mortality. Cholestasis and accumulation of bile acids (BAs) play a major role in chronic liver disease. Aim We aimed to evaluate the clinical role of serum BAs in patients with HPS. Methods Seventy-four patients with cirrhosis were included in this prospective study. Marker for cholestasis as total and individual serum BAs, bilirubin, alkaline phosphatase (AP), and gamma-glutamyl transpeptidase (GGT) were analyzed in patients screened for HPS. Criteria of HPS were fulfilled in 26 patients (35 %). Results In contrast to AP and GGT, bilirubin and serum BAs were significantly elevated in patients with HPS (median total BAs in HPS 83.5 μmol/L, IQR 43.1 - 148.9 vs. no HPS 26.9 μmol/L, 11 - 75.6; p < 0.001). Total BAs correlated with gas exchange by means of PaO2 / AaPO2 (r: -0.28, p < 0.05; r: 0.24, p < 0.05) and portal pressure (r: 0.33, p < 0.05). BAs were associated with HPS independently severity of underlying liver disease (OR: 1.012, 95 % CI: 1.001 - 1.023, p < 0.05). Conclusion BA retention is associated with HPS and gas exchange abnormalities. Future studies should assess whether modulation of BAs signaling may impact the course of HPS.