Objective To investigate the relationships of serum C-C motif chemokine ligand 2 (CCL2) and C-X-C motif chemokine ligand 16 (CXCL16) with inflammatory response and prognosis in children with asthma induced by Mycoplasma pneumoniae (MP) infection.

Methods A total of 166 children with asthma induced by MP infection (asthma group), 166 children with simple MP infection (MP infection group), and 166 healthy children undergoing physical examination (control group) were prospectively selected as the study subjects. According to the 6-month follow-up prognosis, children in the asthma group were divided into poor prognosis group and good prognosis group. Pearson correlation analysis was used to evaluate the correlation between serum CCL2 and CXCL16 levels and levels of inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-17 (IL-17) in children with asthma induced by MP infection. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis were used to analyze the relationship between serum CCL2, CXCL16 and the prognosis of children with asthma induced by MP infection and their predictive efficacy. Decision curve analysis was used to evaluate the net benefit of serum CCL2 and CXCL16 in predicting poor prognosis in children, individually and in combination.

Results The levels of serum CCL2, CXCL16, TNF-α, IL-6, and IL-17 in the MP infection group and the asthma group were higher than those in the control group, and those in the asthma group were higher than those in the MP infection group, with statistically significant differences (P < 0.05). Pearson correlation analysis showed that serum CCL2 and CXCL16 levels in children with asthma induced by MP infection were positively correlated with TNF-α, IL-6, and IL-17 levels, respectively (r=0.743, 0.824, 0.759 and r=0.741, 0.723, 0.714, P < 0.001); CCL2 and CXCL16 levels were also positively correlated (r=0.748, P < 0.001). After 6 months of follow-up, the poor prognosis rate in the asthma group was 36.75% (61/166). Compared with the good prognosis group, the poor prognosis group had a higher proportion of children with severe illness, elevated eosinophil (EOS) count and levels of TNF-α, IL-6, IL-17, CCL2, and CXCL16, and decreased Childhood Asthma Control Test (C-ACT) score and forced expiratory volume in the first second to forced vital capacity ratio (FEV₁/FVC), with statistically significant differences (P < 0.05). Multivariate logistic regression analysis showed that severe illness, high CCL2 level, and high CXCL16 level were independent risk factors for poor prognosis in children with asthma induced by MP infection, while high C-ACT score and high FEV1/FVC were independent protective factors (P < 0.05). ROC curve analysis showed that the areas under the curve for predicting poor prognosis in children by C-ACT score, CCL2, CXCL16 individually and CCL2 combined with CXCL16 were 0.787, 0.801, 0.792 and 0.871, respectively. Decision curve analysis showed that within the threshold probability range of 0.20 to 0.85, the net benefit of combined prediction by CCL2 and CXCL16 was higher than that of C-ACT score and serum CCL2 and CXCL16 individually.

Conclusion Elevated serum CCL2 and CXCL16 levels are associated with aggravated inflammatory response and poor prognosis in children with asthma induced by MP infection, and their combined detection has high predictive efficacy for prognosis.