title: Chlamydia pneumoniae infection in community-acquired pneumonia in Taiwan.
abstract: Chlamydia pneumoniae is a common cause of pneumonia worldwide. This study examined the role of C. pneumoniae in 229 patients with community-acquired pneumonia. The ages of the patients ranged from 2 to 95 years. Sera were assayed for IgM and IgG antibodies with microimmunofluorescence (MIF). An IgM titer equal to or greater than 1:20 and IgG titer equal to or greater than 1:64 were considered positive. The prevalence of positive IgG among all of the patients was 75.1% (172/229). The seroprevalence was 81.8% (9/11) for patients in the 11- to 20-year-old group, 63.6% (14/22) in the 31- to 40-year-old group and 88.1% (52/59) in the 71- to 80-year-old group. All patients had a negative result for IgM antibody. Twenty-five of the patients had an IgG titer equal to or greater than 1:512, indicating the presence of current infection or reinfection. Age older than 60 years (vs. < or = 60 years) was a risk factor for C. pneumoniae seropositivity in patients with community-acquired pneumonia (p < 0.001). Males had a significantly higher seroprevalence of C. pneumoniae infection (p = 0.1010). Patients older than 60 years were more likely to have C. pneumoniae infection (p = 0.1107). In this series, C. pneumoniae infection accounted for 10.9% (25/229) of community-acquired pneumonia. The most common clinical manifestations included fever (92%), productive cough (52%), white blood cell more than 10,000/mm3 (56%), and bilateral pulmonary infiltrate (60%).
authors.affiliation: Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: J S
authors.initials: JS
authors.lastname: Wu
authors.forename: J C
authors.initials: JC
authors.lastname: Lin
authors.forename: F Y
authors.initials: FY
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002690:Chlamydia Infections / Q000453:epidemiology*; D016993:Chlamydophila pneumoniae; D017714:Community-Acquired Infections / Q000453:epidemiology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013624:Taiwan / Q000453:epidemiology