Key Histopathologic Features of Liver Biopsies That Distinguish Biliary Atresia From Other Causes of Infantile Cholestasis and Their Correlation With Outcome: A Multicenter Study

The liver biopsy guides diagnostic investigation and therapy in infants with undiagnosed cholestasis. Histologic features in the liver may also have prognostic value in the patient with biliary atresia (BA). We assessed the relative value of histologic features in 227 liver needle biopsies in discriminating between BA and other cholestatic disorders in infants enrolled in a prospective Childhood Liver Disease Research Network (ChiLDReN) cohort study by correlating histology with clinical findings in infants with and without BA. In addition, we reviewed 316 liver biopsies from clinically proven BA cases and correlated histologic features with total serum bilirubin 6 months after hepatoportoenterostomy (the Kasai procedure, HPE) and transplant-free survival up to 6 years. Review pathologists were blinded to clinical information except age. Semiquantitative scoring of 26 discrete histologic features was based on consensus. Bile plugs in portal bile ducts/ductules, moderate to marked ductular reaction, and portal stromal edema had the largest odds ratio for predicting BA versus non-BA by logistic regression analysis. The diagnostic accuracy of the needle biopsy was estimated to be 90.1% (95% confidence interval [CI]: 85.2%, 94.9%), whereas sensitivity and specificity for a diagnosis of BA are 88.4% (95% CI: 81.4, 93.5) and 92.7% (95% CI: 84.8, 97.3), respectively. No histologic features were associated with an elevated serum bilirubin 6 months after HPE, although it (an elevated serum bilirubin) was associated with an older age at HPE. Higher stages of fibrosis, a ductal plate configuration, moderate to marked bile duct injury, an older age at HPE, and an elevated international normalized ratio were independently associated with a higher risk of transplantation.