Detection of Chlamydia trachomatis in urine samples by nucleic acid tests: Comparison with culture and enzyme immunoassay of genital swab specimens

Two commercially available nucleic acid-based tests, ligase chain reaction (LCR; Abbott Laboratories) and PCR (Roche Diagnostics), for the detection of Chlamydia trachomatis in male and female urine samples were compared with culture and enzyme immunoassay (EIA) (Microtrak; Syva) for C. trachomatis detection in genital samples, The samples were collected from 1,005 patients who attended a sexually transmitted disease clinic, In this study population, the prevalence of the infection was 4%, Specimens which were reactive in any of the tests were retested with a different PCR test using primers directed against the major outer membrane protein gene, With a ''gold standard'' of a positive culture, or any other positive test result if it was confirmed by an independent test, the Roche PCR (95% sensitive, 99.9% specific) was more sensitive than the LCR (75% sensitive, 100% specific) (chi(2), P < 0.0001) while both tests were more sensitive than culture (58% sensitive, 100% specific) or EIA (45% sensitive, 100% specific) (chi(2), P < 0.001), The Roche PCR and Abbott LCR tests of urine identified 65% and 30% more positive patients, respectively, than did testing by culture of urethral or cervical specimens, Nucleic acid testing of urine specimens for C. trachomatis is a more sensitive and convenient method for the detection of genital infection.