Intrahepatic mast cell population correlates with clinical outcome in biliary atresia

Purpose: To determine if mast cells influence the clinical outcome in biliary atresia (BA), the authors examined the intrahepatic mast cell population in BA. Methods: Mast cells were identified histochemically using Toludin Blue and immunohistochemically using antimast cell tryptase antibody in formalin-fixed paraffin-embedded sections from 21 cases of BA. Patients were divided into 3 groups; group I (n = 8) with good liver function, group II (n = 8) with moderate liver dysfunction, and group III (n = 5) with severe liver dysfunction. Liver biopsies from patients with choledochal cysts (CDC, n = 5), and normal liver (NL, n = 4) served as controls. The results were compared among the groups. Results: Both histochemical and immunohistochemical methods showed similar data. Mast cells were seen mostly in the portal tracts. Mast cell numbers per medium power field (20x magnification) were higher in BA than in the controls (15.03 ± 2.25 v 3.85 ± .65, [mean ± SEM], P < .05, BA v CDC; 15.03 ± 2.25 v 1.73 ± .06, [mean ± SEM], P < .05, BA v NL, immunohistochemical data). Clinical correlation showed an association between higher mast cell number and liver dysfunction (32.62 ± .80 v 8.52 ± .87 [mean ± SEM], group III v group I; P < .05, immunohistochemical data). Conclusion: Increased mast cell population in BA adversely affects liver function and raises the possibility that type I allergic reaction may play role in the pathology of BA. Copyright (C) 2000 by W.B. Saunders Company.