Diagnostic value of routine biochemical markers for biliary atresia in neonates with cholestasis: a retrospective study

Background Early diagnosis of biliary atresia (BA) is essential for improving outcomes, but distinguishing it from other causes of neonatal cholestasis (NC) remains difficult. This study aimed to evaluate the diagnostic performance of routine biochemical markers in neonates and determine optimal cutoff values for BA. Methods We retrospectively analyzed 226 neonates with cholestasis admitted between 2018 and 2025. Based on intraoperative cholangiography or clinical follow-up, 53 were diagnosed with BA and 173 with non-BA cholestasis. Demographic and laboratory data were compared between groups. ROC curve analysis was used to determine optimal thresholds, and variables with statistical significance were included in multivariate logistic regression. Results Compared to the non-BA group, the BA group had significantly higher levels of gamma-glutamyl transferase (GGT), total bile acid (TBA), and direct bilirubin (DBIL) (all P < 0.001). ROC analysis revealed the optimal cutoff values for diagnosing BA as: GGT 274.5 U/L (AUC = 0.882), TBA 67.4 µmol/L (AUC = 0.826), and DBIL 46.2 µmol/L (AUC = 0.764). In multivariate logistic regression, all three markers remained significant independent predictors. GGT > 274.5 U/L showed the highest odds ratio (OR = 30.758, 95% CI: 5.989–157.965, P < 0.001), followed by TBA > 67.4 µmol/L (OR = 10.508, P = 0.010) and DBIL > 46.2 µmol/L (OR = 5.044, P = 0.046). Conclusion GGT, TBA, and DBIL are reliable, noninvasive biochemical markers for the early diagnosis of BA in neonates. Their age-specific cutoff values may assist in early screening and timely intervention for affected neonates.