Clinical significance of plasma endothelin levels in patients with biliary atresia

Biliary atresia (BA) is the end-result of a destructive inflammatory process that affects intra- and extrahepatic bile ducts, leading to fibrosis and obliteration of the biliary tracts with the development of biliary cirrhosis and portal hypertension (PH). Endothelins (ET) are 21-amino-acid peptides of endothelial origin with potent vasoconstrictor activity that bind to various cells of the liver. Nothing is presently known about plasma ET levels in BA. The aim of this study was to determine the clinical significance of plasma ET levels in patients with BA after hepatic portoenterostomy (Kasai's procedure) and to correlate these with liver function tests (LFT) and PH. We measured plasma concentrations of ET in 19 patients with BA (5 boys and 14 girls; mean age 11.6 ± 5.5 years) after portoenterostomy and 10 age-matched controls. Patients were grouped according to outcome based on LFT: group A consisted of 9 patients with an ‘‘unfavorable outcome” and Group B 10 patients with a “favorable outcome”. The plasma ET levels were measured using a highly sensitive and specific enzyme immunometeric assay (EIA). No patient had ascites or hepatorenal syndrome. Plasma ET levels were significantly higher in patients with BA than in controls (3.42 ± 0.42 vs 1.75 ± 0.39 pg/ml, respectively; P < 0.01) and in patients in group A than in group B. (3.75 ± 0.25 vs 3.06 ± 0.23 pg/ml, respectively; P < 0.01). In group A, plasma ET levels were higher in patients with PH (n = 4) than in those without PH (n = 5) (3.99 ± 0.06 vs 3.64 ± 0.22 pg/ml, respectively; P < 0.05). We conclude that plasma ET levels are high in patients with BA, especially those with severe biliary cirrhosis, and that ET may partially contribute to development of PH in BA. The results of the present study also suggest that plasma ET concentrations may be a useful marker in the follow-up of patients with BA. Accepted: 12 September 1997