The molecular diagnosis of lymphogranuloma venereum: evaluation of a real-time multiplex polymerase chain reaction test using rectal and urethral specimens.

OBJECTIVES: The objectives of this study were to evaluate the use of a real-time multiplex polymerase chain reaction (M-PCR) assay to differentiate between trachoma and lymphogranuloma venereum (LGV) biovars of Chlamydia trachomatis and to validate its performance with the conventional genotyping method.

STUDY: Swab specimens from 115 patients with anorectal symptoms or syndromes associated with LGV were tested by a real-time M-PCR assay and the results compared with the PCR-based restriction fragment length polymorphism analysis of the major outer membrane protein gene (omp1).

RESULTS: A high agreement of 96.5% (111 of 115 specimens) was found between the real-time M-PCR testing and the standard genotyping method for the detection of C. trachomatis DNA (kappa value, 0.945, P <0.00001). Both methods identified 53 LGV, 32 non-LGV C. trachomatis, and 26 negative specimens.

CONCLUSIONS: The real-time M-PCR assay simultaneously detects and differentiates LGV from non-LGV strains using swab specimens. This assay offers a relatively rapid and sensitive alternative for the diagnosis of LGV infection and is a useful tool for screening and for outbreak investigations.