To evaluate the clinical utility of targeted next-generation sequencing (tNGS) for pathogen detection of pediatric acute lower respiratory tract infections (ALRTIs), with a particular focus on the use of throat swab samples. In this diagnostic accuracy study involving 132 children, throat swabs and bronchoalveolar lavage fluid (BALF) samples were collected and analyzed by tNGS, and the results were compared with those obtained from conventional diagnostic methods. The impact of prior antibiotic use on the detection rate of tNGS was evaluated, the consistency between throat swabs and BALF was assessed, and the economic cost and invasiveness of the sampling methods were examined. This study enrolled 132 children, of whom 79 (60%) were boys and 53 (40%) were girls. Ninety-two (70%) of the patients had fever, and 128 (97%) had a cough. The detection rates of bacteria, viruses, and atypical pathogens in BALF samples by tNGS were 89.5% (n = 68), 98.2% (n = 108), and 77.8% (n = 63), respectively. Compared to traditional detection methods, tNGS showed significantly higher detection rates for bacteria and viruses (P < 0.001), but there was no statistically significant difference in the detection of atypical pathogens (P = 0.59). The use of antibiotics had no significant effect on bacterial detection by tNGS (P = 0.237). Using BALF-tNGS as the “gold standard,” the sensitivities of tNGS of throat swabs for detecting bacteria, viruses, and atypical pathogens were 95.83%, 88.16%, and 92.06%, respectively, with specificities of 55.95%, 83.93%, and 100%. In the analysis of economic costs and invasiveness, the cost of throat swab sampling was significantly lower than that of BALF sampling, and the associated pain score and complication rate were significantly lower (P < 0.05). tNGS with throat swabs offers higher sensitivity and specificity than traditional methods for diagnosing pediatric ALRTIs. As such, it offers a less invasive, more cost-effective alternative to BALF sampling.

Introduction: Plastic bronchitis (PB) is a rare but severe complication of Mycoplasma pneumoniae pneumonia (MPP) in children. Early identification of PB is critical for timely intervention. This study aimed to develop and validate a nomogram incorporating the CD4+/CD8 + ratio to predict PB risk in children with MPP who underwent bronchoscopy.Methods: This single-center, retrospective cohort study was conducted at Fujian Children's Hospital, China, from January 2023 to December 2024. A total of 281 children hospitalized with MPP, including 39 patients who developed PB, were included. Key predictors for nomogram were selected out of 19 variables using least absolute shrinkage and selection operator regression, followed by multivariable logistic regression. Model performance was evaluated through discrimination, calibration, and decision curve analysis (DCA). Internal validation was performed using the Bootstrap method with 1,000 resamples.Results: The nomogram incorporated four independent predictors—fever duration, atelectasis, elevated D-dimer, and reduced CD4+/CD8 + ratio. It demonstrated strong discrimination (AUC = 0.83, 95% CI 0.77–0.90) and calibration (Hosmer-Lemeshow P = 0.303), with superior net benefit across risk thresholds of 0.1–0.7 by decision curve analysis, supporting its clinical utility for early risk stratification. Bootstrap validation confirmed robust performance with minimal overfitting.Discussion: CD4+/CD8 + ratio based nomogram provides a practical tool for predicting PB risk in children with MPP, which may facilitate early bronchoscopy leading to improved patient outcomes.

To explore the effect of targeted second-generation sequencing technique to guide clinical diagnosis and medication on the therapeutic effect and prognosis of respiratory tract infection (RTI) in children. During January 2021 to June 2022, 320 children with RTI cured were selected in our hospital as the object of this retrospective study. The control group accepted empirical broad-spectrum antibacterial therapy and the observation group accepted targeted second-generation sequencing technique to guide diagnosis and medication. The therapeutic effect, improvement time of clinical symptom index, laboratory-related index, level of inflammatory factors, incidence of complications, and parents’ treatment satisfaction were compared. The observation group was considerably more efficacious (91.25%) versus the controlled group (72.50%). The duration of enhancement of fever, nasal congestion, tonsillar congestion, and cough symptoms was shorter in the observation group (P < .05). Serum levels of iron, IgA, IgG as well as IgM were substantially elevated in the observation group. The levels of IL-4 and IL-10 were markedly reduced in the observation group after treatment. The prevalence of complications was considerably below that of the comparison group (21.25%) in the observation group (8.75%). Parental satisfaction with therapy was markedly higher in the observation group (92.50%) than in the control group (66.25%). The application of targeted second-generation sequencing technology to guide clinical diagnosis and drug use can elevate the RTIs efficacy and prognosis in childhood. Targeted second-generation sequencing can achieve precise treatment, reduce drug resistance of drug-resistant strains, and improve the efficacy. It has high promotion and application value.

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.

Introduction: Childhood asthma (CA) is a common chronic respiratory condition that significantly impacts the respiratory function and quality of life of affected children. With a rising global incidence, CA poses substantial physical, psychological, and economic burdens. This study aimed to elucidate the role of pyroptosis-related differentially expressed genes (PRDEGs) in CA by conducting a comprehensive bioinformatics analysis using an integrated dataset from the Gene Expression Omnibus.Methods: Differential expression analysis was performed using the R package limma, identifying 2,069 differentially expressed genes (DEGs), with 1,158 upregulated and 911 downregulated genes in CA compared with the control group. Among these DEGs, 45 PRDEGs were identified, suggesting the potential involvement of pyroptosis in the pathological processes of CA. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that PRDEGs were primarily enriched in biological processes related to the immune response, cell disassembly, and inflammatory pathways.Results: Immune cell infiltration analysis using the CIBERSORT algorithm revealed significant differences between the CA and control groups, with increased macrophages M0, activated mast cells, and γδ T cells and decreased resting natural killer cells in the CA group. Among the six hub genes identified, BAX, BECN1, MAVS, and BCL2 exhibited statistically significant expression differences between the groups (p < 0.05 in GEO data; p < 0.0001 or p < 0.001 in quantitative real-time polymerase chain reaction validation), while NOD2 and NFKBIA showed no significant differences. Receiver operating characteristic analysis of BAX, BECN1, MAVS, and BCL2 supported their potential as diagnostic biomarkers for CA, with area under the curve values ranging from 0.602 to 0.621 (95% confidence interval: 0.510–0.712).Discussion: Our findings provide novel insights into the molecular mechanisms underlying CA and highlight the diagnostic potential of BAX, BECN1, MAVS, and BCL2 as biomarkers. Targeting PRDEGs may offer new therapeutic avenues, and further research is warranted to validate these findings and explore the clinical applicability of suggested biomarkers in precision medicine for managing CA.