Detection of Chlamydia trachomatis in urine specimens from women by ligase chain reaction

The performance of a plasmid-based ligase chain reaction (LCR) with urine specimens was compared with those of cell culture of cervical swabs and enzyme immunoassay with urine specimens for the detection of Chlamydia trachomatis infection in women who had attended a family planning clinic. The prevalence of chlamydial infection determined by LCR was 3.1%. Discrepant results among the three assays were resolved by testing urine by a second LCR assay based on the C. trachomatis chromosomal gene encoding the major outer membrane protein. Sensitivity, specificity, and positive and negative predictive values for the cell cultures were 56.3, 100, 100, and 98.4%, respectively, whereas those for the enzyme immunoassay were 18.8, 100, 100, and 97.1%, respectively, and those for LCR were 87.5, 100, 100, and 99.5%, respectively. LCR thus provides a highly sensitive and specific noninvasive screening method for detecting genital chlamydial infections in women.