Usefulness of a scoring system in the interpretation of histology in neonatal cholestasis

AIM: To ascertain the usefulness of a histological scoring system devised to assist in the interpretation of liver histology in neonatal cholestasis (NC).

METHODS: Liver biopsy specimens obtained from infants with NC referred to a tertiary pediatric unit in Malaysia were prospectively studied. The first author, blinded to the final diagnosis, devised the histological diagnosis based on a 7-feature (portal ductal proliferation, bile plugs in portal ductules, porto-portal bridging, lymphocytic infiltration in portal region, multinucleated hepatocytes, neutrophilic infiltration, hepatocellular swelling), 15-point (0 to 15) scoring system. The author classified the histological diagnosis as either biliary atresia (BA) or neonatal hepatitis (NH, all other diagnoses), and subsequently compared the author's diagnosis with the final diagnosis.

RESULTS: Eighty-four biopsy specimens obtained from 78 patients were reviewed. Without the scoring system, BA was correctly diagnosed by the author histologically in 30 cases, labelled as NH in 3. For other diagnoses, BA was excluded correctly in 33 cases and mislabeled as BA in 2 cases. The overall sensitivity for BA was 91%, specificity 86% and accuracy 88%. With the scoring system, a score of >or=7 had the best diagnostic utility to differentiate BA from other intrahepatic cholestasis histologically (sensitivity 88%, specificity 94%, accuracy 92%). Four patients with a score<7 had BA, and 3 patients with a score>or=7 had NH.

CONCLUSION: A 7-feature, 15-point histological scoring system had good diagnostic accuracy in the interpretation of liver histology in neonatal cholestasis.