The Association Between Respiratory Viruses and Asthma Exacerbation in Children Visiting Pediatric Emergency Department: A Retrospective Cohort Study

<b>Background/Objectives:</b> Respiratory viral infections are a major cause of asthma exacerbations. However, studies examining the association between symptoms, signs, treatments, outcomes of asthma exacerbations, and various respiratory viruses in children are limited. This study aims to investigate the association between respiratory viral infections and clinical symptoms and signs, treatment, and hospital admission in children with asthma exacerbations visiting the pediatric emergency department. <b>Methods:</b> This study examined 395 children under 15 years of age who had a previous diagnosis of bronchial asthma, experienced asthma exacerbation, and visited an emergency center between 1 July 2015 and 30 June 2017. Among the 395 participants, respiratory virus polymerase chain reaction (PCR) was conducted in 96 patients (24.3%). The symptoms and signs of asthma exacerbation (dyspnea, tachypnea, chest retraction, wheezing, and gastrointestinal symptoms), treatment (oxygen supplementation and systemic steroid administration), symptom relief within 1 h, and hospital admission were analyzed. <b>Results:</b> Among the 96 patients who underwent respiratory virus PCR, at least one respiratory virus was detected in 72 (75.0%), and over two viruses were detected in 21 children (21.9%). Three common viruses were detected: rhinovirus in 59 (61.5%), adenovirus in 10 (10.4%), and respiratory syncytial virus (RSV) in nine children (9.4%). Rhinovirus infection was associated with tachypnea (adjusted odd ratio (aOR) 4.457, <i>p</i> = 0.007), chest retraction (aOR 3.142, <i>p</i> = 0.013), and systemic steroid administration (aOR 3.065, <i>p</i> = 0.034). Adenovirus infection was associated with oxygen supplementation via nasal cannula (aOR 5.297, <i>p</i> = 0.042). <b>Conclusions:</b> Rhinovirus was associated with tachypnea, chest retraction, and systemic steroid administration, while adenovirus was linked to oxygen supplementation in childhood asthma exacerbations. These findings will help clinicians to better observe asthma symptoms, select appropriate treatments, and improve outcomes for asthma exacerbations.