Background: Mycoplasma pneumoniae has been implicated in asthma exacerbations and chronic asthma. A 2-year longitudinal study has been conducted to investigate the role of M. pneumoniae infections in 168 and 20 hospitalized children and adults, respectively, with asthma exacerbation compared with outpatients (88 children and 48 adults) with chronic asthma (without an exacerbation). The prevalence of Chlamydia pneumoniae and respiratory viruses was also assessed in these 2 populations.
Methods: Lung function testing, blood sampling and microbiological testing (polymerase chain reaction, culture and serology) were performed for 256 children and 68 adults followed by a 7-week, follow-up visit with repeated blood sampling for serological testing and phone interviews at 6 and 12 months later.
Results: M. pneumoniae infection was more prevalent in children with chronic asthma (13.6%) compared with children with exacerbation (7.1%), while the reverse was true in adults (6.3 vs. 10.0%, respectively). However, these differences were not statistically significant. Acute C. pneumoniae infection was identified in 3.9% of children and 7.4% adults. Children seen for chronic asthma were significantly more likely to be infected with C. pneumoniae than children hospitalized for an asthma exacerbation. Viruses were the most prevalent microorganisms detected in children with an asthma exacerbation. No differences in the outcome parameters were identified between M. pneumoniae-infected and noninfected patients.
Conclusions: The present study suggests that M. pneumoniae does not play a direct role in the pathogenicity of acute or chronic asthma in most children.