Clinical, laboratory, and microbiological factors associated with bronchiolitis severity: a prospective study

Year 2026, Volume: 9 Issue: 2, 511 - 518, 12.03.2026

Abdullah Akkuş , Ahmet Osman Kılıç , Sevgi Pekcan , Fatih Ercan , Mehtap Yücel , Muhammet Zahit Koyuncu , Hasan Çetin , Mustafa Osman Şimşekler , Hanife Tuğçe Çağlar , Mustafa Gençeli , Özge Metin , Abdullah Yazar , Fatih Akın

https://izlik.org/JA72MS59PX

Abstract

Aims: Bronchiolitis is a leading cause of pediatric emergency visits and hospitalization in infants, with a broad spectrum of clinical severity. This prospective study aimed to evaluate demographic, clinical, laboratory, radiological, and microbiological characteristics of children with bronchiolitis and to analyze their association with disease severity according to Wang’s criteria.
Methods: A total of 305 children aged 0–24 months who presented to the pediatric emergency department of our institution and were diagnosed with bronchiolitis were prospectively enrolled. Patients were classified as having mild, moderate, or severe bronchiolitis. Demographic features, clinical findings, laboratory parameters, imaging results, respiratory support requirements, length of hospital stay, and viral and bacterial etiologies were recorded and analyzed.
Results: The median age was 7 months, and 61.6% of patients were male. Mild, moderate, and severe bronchiolitis were observed in 49.8%, 31.5%, and 18.7% of patients, respectively. Recurrent respiratory tract infections were more frequent in moderate and severe disease (29.2% and 22.8%) compared with mild cases (11.2%; p=0.001). Chronic comorbidities were also associated with higher severity (p=0.007). Hospitalization rates increased significantly with severity (14.5% in mild vs 80.2% in moderate and 57.9% in severe cases; p<0.001). Viral pathogens were detected in 21.1% of mild, 67.7% of moderate, and 77.2% of severe bronchiolitis cases (p<0.001). Bacterial superinfection was significantly more common in severe bronchiolitis (14.0%) than in mild (1.3%) and moderate (2.1%) groups. Median length of hospital stay increased from 1 day in mild cases to 6 days in moderate and severe cases (p<0.001).
Conclusion: Bronchiolitis severity was associated with viral detection and bacterial superinfection. Patients with confirmed viral infection or bacterial superinfection may represent patients with an increased likelihood of prolonged respiratory support and hospitalization. Early comprehensive assessment may help identify high-risk patients and optimize management in pediatric emergency settings.

Keywords

Bronchiolitis , children , disease severity , respiratory support

Ethical Statement

After approval from Ethics Committee on Non-Pharmaceutical and Non-Medical Device Research (Date: January 5, 2024; Approval No: 2024/4727), the study was conducted in accordance with the principles of Declaration of Helsinki.

Supporting Institution

No financial support was received for this study.

Thanks

None

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