CXCL12 and CXCL13 as potential biomarkers for disease severity and recurrence in respiratory syncytial virus bronchiolitis.

To examine chemokine expression in children with Respiratory Syncytial Virus (RSV) bronchiolitis and evaluate its clinical utility for early warning and prognosis. Five hospitalised RSV bronchiolitis children and five matched controls were studied. To validate findings, 50 RSV infants and 30 controls were assessed for recurrent wheezing after 1 year. Blood leukocyte RNA-seq identified RSV-associated hub genes via GO/KEGG analysis, with flow cytometry confirming chemokine expression. Twelve hub genes were identified, with 712 differentially expressed genes (292 upregulated, 420 downregulated). RSV patients showed elevated CXCL2, CXCL12, CXCL13, CCL13, and CCL24 (P < 0.05). CXCL12 was higher in moderate-to-severe cases (Area Under the Curve, AUC = 0.835, 95% CI 0.714-0.956, P < 0.05), while CXCL13 was elevated in recurrent wheezers (AUC = 0.851, 95% CI 0.711-0.991, P < 0.05). CXCL12 predicted severity, and CXCL13 predicted recurrence (ROC-confirmed, P < 0.05). CXCL12 and CXCL13 may serve as biomarkers for assessing RSV bronchiolitis severity and predicting recurrence, aiding early clinical evaluation and prognosis.