To assess the sensitivity of the ligase chain reaction (LCR) assay for Chlamydia trachomatis in vaginal swabs from women who were positive in cervical samples and/or urines.Subjects
413 women attending the genitourinary medicine clinic, St Mary's Hospital, Paddington.Methods
The LCR assay was used to test vaginal swabs from 46 women who were C trachomatis positive at one or both of the other sites by direct fluorescent antibody (DFA) staining, by an enzyme immunoassay (EIA), or by the LCR assay.Results
The LCR assay of vaginal swabs had the following sensitivity values using confirmed positive results: 93% (41/44) compared with DFA staining of cervical deposits, 93% (41/44) compared with the LCR assay of cervical samples, 93% (28/30) compared with an EIA for cervical samples, 91% (39/43) compared with DFA staining of urine deposits, and 93% (39/42) compared with the LCR assay of urine. Four women had vaginal swab samples negative by the LCR assay; one was positive only in the urine and two had cervical samples containing a small number of chlamydial elementary bodies.Conclusion
Testing vaginal swabs by the LCR assay is a sensitive method of detecting chlamydial infection; the results suggest that this procedure could be used as an alternative to examining urines in a screening programme for chlamydial infection in the community.