Serum Interleukin-6 and Ventricular Tachycardia as Predictors of Mortality in Children With Fulminant Myocarditis.

BACKGROUND

Fulminant myocarditis (FM) is still associated with a high mortality in children. This study aims to provide clinical indicators that will enable early identification of children with FM at high risk of death and predict the mortality.

METHOD: A total of 40 children diagnosed with FM from January 2014 to March 2024 at our hospital were retrospectively analysed. Baseline demographic characteristics and relevant clinical data including basic vital signs, clinical presentation, and clinical findings were collected at admission and follow-up. Binary logistic regression analysis and receiver operating characteristic curves were used to screen for factors with clinical predictive value. Spearman correlation analysis was used to detect the correlation between interleukin-6 (IL-6) and disease severity.

RESULTS

A total of 40 children with FM were included in this study and were divided into a survival group (n=34) and a death group (n=6). The most common clinical symptom was circulatory disorders (n=28; 70.0%). There were significant differences between the two groups in creatine kinase (CK) (p=0.031), serum IL-6 (p<0.001), left ventricular end-systolic diameters (p=0.041), and ventricular tachycardia (VT) (p=0.019). The multivariate logistic regression analysis of serum IL-6 and VT showed that IL-6 (odds ratio [OR] 1.094; 95% confidence interval [CI] 1.027-1.166; p=0.006), and VT (OR, 0.096; 95% CI 0.010-0.920; p=0.042) were independently associated with mortality. The results of receiver operating characteristic curve analysis showed that serum IL-6 (area under the curve [AUC] 0.975; 95% CI 0.894-1), VT (AUC 0.755; 95% CI 0.541-0.868), with a cut-off value of IL-6 of 24.60 pg/mL, a sensitivity of 100%, a specificity of 97.1%, and a Youden index of 0.971, suggesting that high levels of serum IL-6 (>24.60 pg/mL) and an electrocardiogram manifesting as VT have a predictive value for mortality, in which serum IL-6 has a very high accuracy. Spearman correlation analysis showed that CK, CK-MB, and aspartate aminotransferase were positively correlated with IL-6 levels, whereas left ventricular ejection fraction was negatively correlated with IL-6 levels, indicating that IL-6 levels are related to disease severity.

CONCLUSIONS

Serum IL-6 levels and VT manifestations on electrocardiogram at admission enable accurate early identification of children with FM at high mortality risk.