Heightened Local T<sub>h</sub>17 Cell Inflammation Is Associated with Severe Community‐Acquired Pneumonia in Children under the Age of 1 Year
Ming Liu, Bingtai Lu, Huifeng Fan, Xuanjie Guo, Shuling Du, Diyuan Yang, Yiping Xu, Yue Li, Di Che, Yunfeng Liu, Xiaoqiong Gu, Tao Ding, Ping Wang, Hai‐Bin Luo, Gen Lu
Abstract
Severe community‐acquired pneumonia (sCAP) early in life is a leading cause of morbidity, mortality, and irreversible sequelae. Herein, we report the clinical, etiological, and immunological characteristics of 62 children age < 1 year. We measured 27 cytokines in plasma and bronchoalveolar lavage (BAL) from 62 children age < 1 year who were diagnosed with CAP, and then, we analyzed correlations among disease severity, clinical parameters, and etiology. Of the entire cohort, three cytokines associated with interleukin‐17‐ (IL‐17‐) producing helper T cells (T h 17 cells), IL‐1 β , IL‐6, and IL‐17, were significantly elevated in sCAP patients with high fold changes (FCs); in BAL, these cytokines were intercorrelated and associated with blood neutrophil counts, Hb levels, and mixed bacterial‐viral infections. BAL IL‐1 β (area under the curve (AUC) 0.820), BAL IL‐17 (AUC 0.779), and plasma IL‐6 (AUC 0.778) had remarkable predictive power for sCAP. Our findings revealed that increased local T h 17 cell immunity played a critical role in the development of sCAP in children age < 1 year. T h 17 cell‐related cytokines could serve as local and systemic inflammatory indicators of sCAP in this age group.