Dong Wang

Background & Objective: The clinical impact of testing timing for targeted next-generation sequencing (tNGS) in pediatric community-acquired pneumonia (CAP) is poorly understood. We hypothesized that early tNGS implementation accelerates clinical recovery and evaluated its comprehensive value. Methodology: In a retrospective study at Fujian Children's Hospital (2021-2023), 199 hospitalized children with CAP (BALF tested) were analyzed. Patients were grouped by tNGS vs. conventional testing (CT), with the tNGS group stratified into early (≤48h) and late (>48h) testing. We compared diagnostic yield, clinical outcomes, therapeutic adjustments, and costs. Results: tNGS demonstrated significantly higher sensitivity than CT for both bacteria (86.0% vs. 19.0%, P<0.001) and viruses (88.1% vs. 26.2%, P<0.001), and excelled at identifying mixed infections (55.8%). Critically, the early-testing group showed significantly shorter times to cough improvement (median 6.0 vs. 9.0 days, P=0.002) and rale resolution (median 7.0 vs. 8.0 days, P=0.027) compared to the late-testing group. This was associated with more timely therapeutic adjustments (P<0.05). A non-significant trend toward lower costs and shorter hospital stays was also observed. Conclusion: Early tNGS implementation in pediatric CAP not only enhances diagnostic yield but, more importantly, accelerates clinical recovery by facilitating timely, targeted therapeutic interventions. These findings provide strong evidence for integrating early tNGS into clinical workflows, marking a shift from simple pathogen identification to an outcome-driven diagnostic strategy.

Objectives: Respiratory syncytial virus (RSV) is a leading cause of hospitalization for acute lower respiratory tract infections (ALRIs) in children, with bacterial coinfection complicating diagnosis and often driving antibiotic overuse. This study aimed to develop and validate a clinical prediction model using common laboratory biomarkers to enable early, accurate identification of clinically significant bacterial coinfection in children with RSV infection. Methods: A single-center, retrospective cohort study was conducted at Fujian Children’s Hospital, enrolling 518 hospitalized children with RSV infection, which was confirmed via targeted next-generation sequencing (tNGS). Patients were randomly divided into a training set (n = 363) and a test set (n = 155) at a 7:3 ratio. The primary outcome, bacterial coinfection, was defined by a composite reference standard integrating etiological evidence from tNGS with clinical, inflammatory, and imaging data, and adjudicated by a blinded expert panel. LASSO regression identified independent predictors, followed by multivariable logistic regression modeling. Model performance was assessed via discrimination (AUC), calibration (Hosmer–Lemeshow test), and clinical utility (Decision Curve Analysis) in both sets. Results: Neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), and serum amyloid A (SAA) were selected as predictors. The model achieved an AUC of 0.832 (95% CI: 0.788–0.875) in the training set and 0.811 (95% CI: 0.737–0.885) in the test set, with well-calibrated predictions (p > 0.05). Decision curve analysis demonstrated net clinical benefit across 10–80% threshold probabilities. A nomogram was developed for practical application. Conclusions: This study established a model integrating NLR, CRP, and SAA. It offers a reliable tool for the early detection of bacterial coinfection in RSV-infected children, enabling targeted antibiotic stewardship and improving clinical outcomes.