Submitted by mrhodes40 on Sat, 2007-06-02 12:03

Clin Diagn Lab Immunol. 2000 Sep;7(5):739-44.
Comparison of five serologic tests for diagnosis of acute infections by Chlamydia pneumoniae.
Persson K, Boman J. Department of Clinical Microbiology, Malmo University Hospital, S-205 02 Malmo, Sweden.
Serology is often used to diagnose acute infections by Chlamydia pneumoniae. In this study paired sera from patients with acute respiratory tract infection during an epidemic of C. pneumoniae infections were examined by five different antibody tests. These tests were the complement fixation (CF) test, the microimmunofluorescence (MIF) test, a recombinant enzyme immunoassay (rEIA) (Medac) based on a recombinant lipopolysaccharide of chlamydia and measuring antibodies to a common chlamydial antigen, and two tests that utilize preparations of C. pneumoniae organisms, the SeroCp-EIA (Savyon) (with preserved lipopolysaccharide) and the LOY-EIA (Labsystems) (without this antigen). Both of the last two tests should measure specific antibodies to C. pneumoniae, although cross-reacting antibodies may also be detected by the SeroCp-EIA. Acute infection of C. pneumoniae was serologically confirmed in 44% of the cases by at least two different tests. Using an expanded "gold standard," i.e., the presence of significant reactions in at least two tests, the sensitivity of the CF test was 69%, that of the MIF test was 88%, that of the rEIA was 89%, that of the LOY-EIA was 96%, and that of the SeroCp-EIA was 92%. Specificity was high for all methods, but adjustments of diagnostic criteria were made to several of the tests. The basis for these adjustments and supportive data are presented. Infections of C. pneumoniae were detected in patients from 8 to 83 years of age. Two peaks in the incidence of such infections were observed: one among young teenagers and a second in adults 30 to 45 years of age, corresponding to parents of young teen-agers. The tests were equally sensitive in different age groups. Reinfections seemed to be rare. PMID: 10973447
[PubMed - indexed for MEDLINE] Whole citation hereĀ 
This research is interesting on a couple of points. First no one test was 100% accurate. The other is mention of a gold standard of significant reactions in two tests to assure they were actually finding CPn. I would like to mention that the VU work used several tests in its work on CPn in MS and many of the research papres against the model used only one. Looking at restults above it is easy to see that such work is not authoritative.