Chlamydophila pneumoniae infection status is dependent on the subtypes of asthma and allergy.

This study was undertaken to investigate the association of Chlamydophila pneumoniae infection (CPI) with asthma and allergy. One hundred forty-one patients with asthma aged 3-21 years, 125 healthy controls aged 3-21 years, and 62 allergic but nonasthmatic patients aged 4-20 years participated in this study. C. pneumoniae-specific antibodies were measured by ELISA. There were no significant differences in the percentage of patients positive for C. pneumoniae-specific antibodies between the three groups. Significantly more allergic asthmatic patients were positive for C. pneumoniae-specific IgA and IgA + IgG than nonallergic asthmatic patients, and this difference remained significant after adjustment for age and gender: adjusted odds ratio (OR) = 5.9 (1.7-26.2) and p = 0.01 for IgA, and OR = 5.2 (1.6-25.8) and p = 0.02 for IgA + IgG. The prevalence of the C. pneumoniae-specific IgA and the IgA + IgG positivity also was significantly lower in the nonallergic asthmatic group than in the allergic and control groups (p < 0.005). No food/drug-allergic patient was positive for C. pneumoniae-specific IgA, whereas 41.6% of the inhalative-allergic patients were positive for this antibody (p = 0.002). In our population CPI does not associate directly with asthma and allergy, but chronic or recurrent infection is associated with allergic asthma and inhalative allergy as opposed to nonallergic asthma and noninhalative allergy.