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 (20 x 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.