Plasma endothelin-1 levels in patients with biliary atresia: possible role in development of portal hypertension

Background. Biliary atresia (BA) is a severe neonatal liver disease characterized by progressive extrahepatic biliary tract and intrahepatic inflammatory process. Hepatic fibrosis and portal hypertension (PH) still occur despite the disappearance of jaundice following successful hepatic portoenterostomy. Endothelin-1 (ET-1) is a potent vasoconstrictor and has been reported to stimulate hepatic collagen synthesis. The aim of this study was to demonstrate the potential role of ET-1 in the pathogenesis of the progressive inflammation, fibrosis and PH in BA. Methods. Thirty pediatric patients with biliary atresia post-hepatic portoenterostomy and 12 healthy children were examined. The ET-1 level was determined by commercially available enzyme-linked immunosorbent assay kits. Results. Endothelin-1 levels were elevated in the patients compared with those of the controls (5.45+/-3.34 vs. 2.74+/-2.17 pg/ml, P =0.01). Moreover, patients with PH also had greater levels of ET-1 than those without PH (6.73+/-3.27 vs. 3.26+/-2.2 pg/ml, P =0.004). Patients with abnormal transaminase enzymes had significantly higher ET-1 levels than those with normal enzymes (6.43+/-3.33 vs. 3.17+/-2.1 pg/ml, P =0.01). In the jaundice-free group, endothelin-1 levels were elevated in the patients with PH compared with those without PH (5.93+/-2.15 vs. 2.88+/-2.1 pg/ml, P =0.02). Conclusions. Our findings showed elevation of plasma ET-1 levels in patients with BA, especially in those with PH. ET-1 levels were also higher in patients with elevated transminase enzymes as well as in the jaundice-free group with PH. ET-1 might play a role in the pathogenesis of the progressive inflammation, fibrosis and PH in BA.