Chlamydia pneumoniae infection in patients with diffuse panbronchiolitis and COPD

Study objectives: To determine the possible association of Chlamydia pneumoniae infection with diffuse panbronchiolitis (DPB) and with COPD, Design: Prospective case-control study, Setting: Division of Respiratory Diseases, Kawasaki Medical School Hospital. Participants: Fifteen DPB and 77 COPD patients who had acute exacerbations of respiratory conditions and 35 and 120 control subjects, respectively, matched for age, sex, and smoking status. Measurements and results: Nasopharyngeal swabs and paired serum samples were obtained from all patients and control subjects for isolation and antibody testing of C pneumoniae, C pneumoniae was isolated from one DPB patient and from no COPD patients or control subjects. Serologic evidence of acute C pneumoniae infection was observed in one DPB patient (6.7%) and six COPD patients (7.8%), The prevalence and mean titer of C pneumoniae IgG and IgA antibodies were significantly higher in COPD patients than in control subjects (p<0.001), However, no such differences were observed between DPB patients and control subjects. Conclusions,, This study showed that C pneumoniae infection may be associated with acute exacerbations of COPD and that chronic C pneumoniae infection is common in COPD but not in DPB.