title: Diagnosis of Chlamydia pneumoniae infection in patients with community-acquired pneumonia by polymerase chain reaction enzyme immunoassay.
abstract: We conducted a prospective study of 385 patients who had community-acquired pneumonia with use of a modified polymerase chain reaction (PCR) assay that detects amplified DNA by enzyme immunoassay (EIA). We used PCR-EIA to improve detection of Chlamydia pneumoniae infection and to differentiate C. pneumoniae infection from other chlamydial infections. Cultures of throat swab specimens from four patients yielded Chlamydia species (C. pneumoniae, one patient; Chlamydia species, two patients; and C. psittaci, one patient). C. pneumoniae was repeatedly detected by PCR-EIA for thirteen (3.4%) of these 385 patients. Six of these 13 patients were infected with the human immunodeficiency virus. Ten (76.9%) of the patients who were positive by PCR-EIA had IgG titers of > or = 1:16, and two (15.4%) of the 13 patients had IgG titers of < 1:16; no sera was available in one case. Other pathogens were recovered in eight (61.5%) of the 13 cases in which C. pneumoniae was detected by PCR-EIA. In addition, for 46 (11.9%) of the 385 patients the titers of antibody were considered diagnostic of C. pneumoniae infection; however, as 36 of the 46 patients were infected with the human immunodeficiency virus (which may have affected their serological response to C. pneumoniae), interpretation of these titers was problematic. As PCR-EIA was more sensitive than was culture for detecting C. pneumoniae infection in this study, this method may be a valuable tool for the prompt diagnosis of this infection.
authors.affiliation: Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
authors.forename: C A
authors.initials: CA
authors.lastname: Gaydos
authors.forename: J J
authors.initials: JJ
authors.lastname: Eiden
authors.forename: D
authors.initials: D
authors.lastname: Oldach
authors.forename: L M
authors.initials: LM
authors.lastname: Mundy
authors.forename: P
authors.initials: P
authors.lastname: Auwaerter
authors.forename: M L
authors.initials: ML
authors.lastname: Warner
authors.forename: E
authors.initials: E
authors.lastname: Vance
authors.forename: A A
authors.initials: AA
authors.lastname: Burton
authors.forename: T C
authors.initials: TC
authors.lastname: Quinn
mesh_terms: D000328:Adult; D000368:Aged; D002690:Chlamydia Infections / Q000175:diagnosis*; D016993:Chlamydophila pneumoniae / Q000235:genetics / Q000302:isolation & purification*; D017714:Community-Acquired Infections / Q000175:diagnosis; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis*; D016133:Polymerase Chain Reaction; D011446:Prospective Studies