PERFORMANCE OF TRANSCRIPTION-MEDIATED AMPLIFICATION AND LIGASE CHAIN-REACTION ASSAYS FOR DETECTION OF CHLAMYDIAL INFECTION IN UROGENITAL SAMPLES OBTAINED BY INVASIVE AND NONINVASIVE METHODS

Based on the amplification of chlamydia-specific I-RNA sequences and t he ligase chain reaction (LCR), the performance characteristics of the Gen-Probe Chlamydia trachomatis transcription-mediated amplification (TMA) assay were evaluated with endocervical, urine, and vulval specim ens from women and urethral and urine specimens from men and mere comp ared with those far cultures ore endocervical, vulval, and urethral sw abs. Of the 308 women and 240 men tested, 25 (8.1%) and 44 (18.3%), re spectively, were shown to be infected, By using the infected individua l as the expanded ''gold standard'' for calculations, the TMA assay an d LCR gave similar performances for the sensitivity of male urethral ( 93.2%) and urine (88.6 and 86.4%) samples, while culture detected only half of the 44 infected men. In women, the sensitivities of the TMA a ssay for endocervical and vulval samples were 88 and 92%, respectively , compared to values of 92% for the LCR on both sample types and of 52 and 8%, respectively, for culture, By using first-void urine for chla mydial diagnosis in women, LCR detected 24 (96%) and TMA assay detecte d 19 (76%) infected individuals, showing a significantly lower sensiti vity for urine in women (P = 0.0253). The results indicate a high over all agreement for both amplifying techniques for ail examined specimen types, except for female urine. Furthermore, they confirm the previou s observation that vulval swabs are an effective alternative noninvasi ve sample type for the detection of C. trachomatis infection in women by nucleic acid-based amplification technologies.