ABSTRACT
Chlamydophila (Chlamydia) pneumoniae infection is increasingly reported worldwide nowadays. We studied twelve Thai adults presenting with the clinical symptoms and signs of community-acquired pneumonia (CAP) due to C. pneumoniae (TWAR) at Pramongkutklao Hospital in Bangkok, Thailand. Their mean age was 38 (range 21-73) years. Six patients lived in Bangkok. Seven patients had comorbid diseases (four cases with allergic asthma, one each with diabetes mellitus, chronic obstructive pulmonary disease and coronary artery disease). C. pneumoniae pneumonia presented as subacute pneumonia in 6 patients. The clinical manifestations were mild (IDSA risk class I-III) except in 4 patients who had preexisting allergic asthma, COPD and coronary heart disease. The diagnosis of C. pneumoniae pneumonia was based on microimmunofluorescence (MIF) antibody technique (IgM titer > or = 1:16, IgG > or = 1:512, IgA > or = 1:256 with or without fourfold rises). The clinical conditions were consistent with the primary infection (IgM titer of 1:16 or higher) in 6 patients and reinfection (IgG titer of 1:512, IgA titer of 1:256 or higher without rises of IgM titer) in the other 6 patients. Minimal bilateral pleural effusion was detected in only one patient. Coinfection was demonstrated in 2 patients (one each with S. pneumoniae and K. pneumoniae). All patients markedly improved after a 2-week course of macrolide, doxycycline or newest fluoroquinolone therapy. All patients had done well at one year of follow-up. C. pneumoniae infection has been recently recognized and a high seroprevalence (37%) in Thai school children and 100 per cent in young male Thai military conscripts has been reported. This report suggests that this infection, C. pneumoniae, may be a common pathogen of CAP in Thailand.