The Science Journal of the American Association for Respiratory Care
Objective: To find out the infection rate and the clinical features of patients with acute respiratory infection caused by Chlamydia pneumoniae (C. Pneumoniae). Method: A prospective study for C.pneumoniae infection was conducted in 110 patients with respiratory tract infection from January-December 1995 in Nanjing. Sputum and throat swab specimens were taken and C. pneumoniae DNA were detected by polymerase chain reaction (PCR) with the HM-1-HR -1 primer pair. At the same time, serum samples were taken and immunoglobulins G and M (IgG and IgM) fractions of antibodies to C. pneumoniae were studied by microimmuno-fluorescence test.
Results: Prevalence of specific IgG was 70% in patients with respiratory tract infection. Seventeen patients (16%) were serologically diagnosed as having recent C. pneumoniae infection and 12 patients (11%) had the positive PCR in sputum and/or swab specimens. The total positive rate was 23% (25/110) combining PCR with serology. Acute infection of C. pneumoniae was common in the patients with asthma (57%), pneumonia (35%), COPD (26%) and bronchitis (25%). The clinical feature between C. pneumoniae infection and non-C.pneumoniae infection was that there was no significant difference. Conclusion: Our data suggest that Chlamydia pneumonia is an important pathogen that causes infections of the human respiratory tract and attention should be drawn to this special illness.