Respiratory Pathogens and Clinical Characteristics of Asthma Exacerbations in Hospitalized Children at a Tertiary Hospital in Türkiye

Background/Objectives: Respiratory pathogens are frequently detected during asthma exacerbations in children. This study aimed to evaluate the distribution of respiratory pathogens, associated clinical features, and factors related to severe exacerbation in children hospitalized for asthma exacerbations during a two-year period. Methods: This retrospective observational study included children aged 1–18 years hospitalized for asthma exacerbation between April 2023 and April 2025. Demographic, clinical, laboratory, and pathogen data were retrospectively obtained from medical records and analyzed. Results: A total of 312 children were included; 135 patients (43.3%) were female, and the median age was 5.70 years (IQR, 3.42–8.79). A respiratory pathogen was detected in 235 patients (75.3%). Among patients with single infections (n = 203), rhinovirus (RV) was the most common pathogen (n = 130), followed by respiratory syncytial virus (RSV) (n = 18). Compared with RSV infection, RV infection was associated with higher frequencies of allergic rhinitis and aeroallergen sensitization, as well as higher neutrophil and eosinophil counts and higher total IgE levels. RV was detected throughout the year, peaking in autumn, whereas RSV occurred predominantly in winter. RSV infection was observed in younger children and was associated with more frequent severe exacerbations in unadjusted comparisons; however, only younger age and moderate-to-severe asthma remained independently associated with severe exacerbation in multivariable analysis. Conclusions: Respiratory pathogens were detected in most children hospitalized for asthma exacerbation, with RV being the predominant pathogen. Younger age and moderate-to-severe asthma were the main factors associated with severe exacerbation.