To investigate the stratification value of combined scoring of procalcitonin (PCT) and amino-terminal pro-B-type natriuretic peptide (NT-proBNP) on the efficacy of methylprednisolone combining integrated blood purification in children with severe sepsis.

A retrospective analysis was conducted on children with severe sepsis who received methylprednisolone combined with integrated blood purification from January 2024 to December 2025. Based on organ function and perfusion status at 72 hours post-treatment, the patients were divided into a treatment response group and a non-response group. Baseline characteristics were compared between the two groups, and a combined PCT and NT-proBNP scoring model was constructed. Multivariate logistic regression was used to analyze independent factors influencing treatment response, while receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis were employed to evaluate the predictive performance and clinical utility of the combined markers.

A total of 117 children patients were included, comprising 68 in the treatment response group and 49 in the non-response group. Compared with the non-response group, the treatment response group exhibited significantly lower baseline pediatric sequential organ failure assessment scores, lactate, PCT, NT-proBNP, and combined scores (all P<0.05). A higher combined score was identified as an independent risk factor for poor treatment response (OR=4.150, 95%CI: 1.892-9.102, P<0.01). According to the stratification of the optimal cut-off value of 0.85, children with higher combined scores exhibited lower treatment response rates, higher 28-day mortality, slower organ function recovery, and longer pediatric intensive care unit (all P<0.05). Based on the combined scoring prediction model, the area under the curve for predicting treatment response was 0.842, with good calibration. Additionally, decision curve analysis demonstrated a high clinical net benefit within reasonable threshold ranges.

Baseline combined PCT and NT-proBNP scoring is associated with the 72-hour early treatment response and 28-day mortality risk in children with severe sepsis treated with methylprednisolone and integrated blood purification. The prediction model constructed based on this score demonstrates favorable discrimination and calibration, suggesting it could serve as a valuable reference for early risk stratification and management.