Risk factors analysis of poor prognosis in ICU-admitted children with severe influenza pneumonia: a retrospective case-control study

This study investigated independent prognostic risk factors for adverse outcomes in children admitted to the ICU with severe influenza pneumonia to guide early risk stratification and timely clinical intervention.

This retrospective study included 139 eligible pediatric ICU patients with severe influenza pneumonia. Univariate and multivariate logistic regression was applied to analyze the independent risk factors for poor prognosis with severe influenza pneumonia, and the Receiver operating characteristic (ROC) curve was used to evaluate the effectiveness of risk factors.

Among the 139 children, 45 had a poor prognosis and 94 had a good prognosis. Multiple clinical and laboratory parameters differed significantly between the two groups (all P\(\:<\)0.05). The three independent risk factors associated with poor prognosis were identified: fever peek \(\:\ge\:\:\)41\({}^\circ \text{C}\)(Odds ration [OR] \(\:=\) 13.584, P\(\:=\) 0.036), requirement for invasive mechanical ventilation (IMV) (OR \(\:=\) 47.526, P\(\:=\) 0.006), and elevated interleukin-6 (IL-6) levels (OR \(\:=\) 1.049, P\(\:=\) 0.002).The optimal cut-off value of IL-6 for predicting poor prognosis was 492.05 pg/mL (Area under the Curve [AUC] \(\:=\) 0.755; sensitivity 46.7\(\:\%\), specificity 94.7\(\:\%\); 95\(\:\%\) Confidence Interval [CI]: 0.666–0.844). The AUCs for fever peak \(\:\ge\:\) 41\({}^\circ \text{C}\) and IMV were 0.623 and 0.737, respectively, whereas the combined AUC for all three indicators reached 0.848 \(\:(\)95\(\:\%\) CI: 0.784–0.912).

Fever peak \(\:\ge\:\)41\({}^\circ \text{C}\), requirement for IMV, and IL-6 levels exceeding 492.05 pg/mL are robust independent early predictors of poor prognosis in children admitted to the ICU with severe influenza pneumonia. Combined assessment of these markers demonstrates strong predictive performance and supports targeted early intervention in high-risk patients.