Immunoglobulin deposits in liver tissue from infants with biliary atresia and the correlation to cytomegalovirus infection.

PURPOSE The aim of this report was to study the amount and distribution of immunoglobulin deposits in liver biopsies from infants with biliary atresia (BA) and correlate the results to the cytomegalovirus (CMV) infection status. METHODS Stored liver biopsies from 18 patients with BA and from 6 control patients without liver disease were immunohistochemically stained to detect IgG and IgM deposits. The intensity of the immunoglobulin staining was evaluated by a semiquantitative scoring scale. Ongoing CMV infection was defined as the detection of CMV-IgM in serum and/or the isolation of CMV in the urine and was noted in 9 of the patients with BA. RESULTS When analyzing the immunoglobulin deposits on the hepatocellular canalicular membrane the intensity score for IgM deposits was significantly higher in biopsies from patients with BA infected with CMV than in those without. No canalicular staining was detected in control biopsies. CONCLUSIONS The results support the possibility that immunologic mechanisms are of importance in the pathogenesis of BA and that a CMV infection may trigger such mechanisms.