Abstract
Objectives In children with hospitalised and non-hospitalised asthma exacerbations, to: (a) describe the point prevalence of respiratory viruses/atypical bacteria using polymerase chain reaction (PCR) and; (b) evaluate the impact of respiratory viruses/atypical bacteria and atopy on acute severity and clinical recovery.
Design This was a prospective study performed during 2009-2011.
Setting The study was performed in the Emergency Departments of 2 hospitals.
Patients 244 children aged 2-16 years presenting with acute asthma to the Emergency Departments were recruited. A nasopharyngeal aspirate and allergen skin prick test were performed.
Main outcome measures The outcomes were divided into (a) acute severity outcomes [Australian National Asthma Council assessment, hospitalisation, Functional Severity Scale, acute asthma score, asthma quality of life questionnaires for parents (PACQLQ) on presentation, asthma diary scores (ADS) on presentation and length of hospitalisation] and (b) recovery outcomes (PACQLQ for 21 days, ADS for 14 days and representation for asthma for 21 days).
Results PCR for viruses/atypical bacteria was positive in 81.7% of children (75.1% human rhinovirus, co-detection in 14.2%). M. pneumoniae and C. pneumoniae were rarely detected. The presence of micro-organisms had little impact on acute asthma or recovery outcomes. Children with atopy were significantly more likely to relapse and represent for medical care by day-14 (OR 1.11, 95%CI 1.00,1.23).
Conclusions The presence of any viruses is associated with asthma exacerbations but does not appear to influence asthma recovery. In contrast, atopy is associated with asthma relapse. M. pneumoniae and C. pneumoniae are rare triggers of acute asthma in young children.