Association of postoperative infection with early bilirubin clearance and native liver survival: a single - center retrospective cohort study

BACKGROUND: Apart from cholangitis, studies focusing on other postoperative infections after the Kasai procedure (KP) in children with biliary atresia (BA) remain limited.This study aimed to investigate the association between post-KP infection and prognosis. METHODS: This retrospective study included children with BA who underwent KP. Postoperative infection was the primary exposure variable of interest in this cohort. The primary outcome measure was post-operative native liver survival, while the secondary outcome measure was mortality attributed to infection. A time-dependent Cox regression model was used to account for the timing of postoperative infection as a time-varying covariate. RESULTS: One. A total of 404 cases included in the study. There were no significant differences in gender, age at operation, or gestational age between the two groups (P > 0.05). Two. Early-onset infection is primarily associated with delayed bilirubin clearance (P < 0.01).Time-dependent Cox regression showed that later onset of infection was associated with better native liver survival (HR = 0.777, 95% CI: 0.719-0.839, P < 0.001). After accounting for measured confounders, each one-month later infection onset corresponded to a 22.3% lower hazard of death or liver transplantation. These findings should be interpreted as associations, not causal effects. CONCLUSION: Postoperative infection in biliary atresia is associated with delayed bilirubin clearance and poorer native liver survival. The timing of infection onset is an important factor associated with native liver survival outcomes. Given the observational design, causality cannot be inferred.