Comparison between the Gen-Probe Transcription-Mediated Amplification Trichomonas vaginalis Research Assay and Real-Time PCR for Trichomonas vaginalis Detection Using a Roche LightCycler Instrument with Female Self-Obtained Vaginal Swab Samples and Male Urine Samples

Abstract

This study compared two assays for Trichomonas vaginalis detection, Gen-Probe's transcription-mediated amplification (TMA) assay for Trichomonas vaginalis and BTUB FRET PCR, using self-obtained clinical samples from 611 patients. Infection status was defined as two positive results by two different tests. The initial TMA assay sensitivity was 96.7%; specificity was 97.5%. The TMA assay was comparable to BTUB FRET PCR.Trichomonas vaginalis is the cause of the most common parasitic sexually transmitted infection in the world and is estimated to 3 million infections in the United States annually (1, 21). T. vaginalis can cause vaginitis, cervicitis, preterm labor, urethritis, and prostatitis (3,32,33). T. vaginalis is cytopathic to vaginal cells and is associated with other sexually transmitted diseases (STDs), including transmission of human immunodeficiency virus (2,7,26,29).Conventional methods for diagnosing T. vaginalis are microscopic examination of wet-mount preparations and culturebased systems. Both methods rely on the collection of viable organisms and suffer from poor sensitivity (25). More sensitive research-based PCRs for the diagnosis of T. vaginalis have been described (9, 11-16, 22, 24).The development of a commercially available amplification assay for T. vaginalis using self-collected samples would be highly desirable from patient, clinical, and public-health perspectives (6). Other commercially available FDA-cleared STD tests, such as those for chlamydia and gonorrhea, could also be performed on the self-obtained samples (4,5,27,28).We report a comparison of a research transcription-mediated amplification (TMA) assay for T. vaginalis, now available as an analyte-specific reagent (Gen-Probe Inc., San Diego, CA), with BTUB FRET PCR (BTUB), a real-time research PCR (9).(Results from this analysis were presented in part at the International Society for Sexually Transmitted Diseases Research, Amsterdam, The Netherlands, 10 to 13 July 2005.)We screened 615 people attending two STD clinics; 611 had male urine samples (n ϭ 290) or duplicate female self-obtained vaginal swabs (SOVS) (n ϭ 321) collected. Institutional Review Board approval was obtained, and the study was funded in part by Gen-Probe. BTUB PCR. For females, two SOVS for BTUB and TMA testing were collected in random order. SOVS for BTUB testing were transported in a dry state and were rehydrated in 1 ml of Tris-EDTA buffer, 200 l of which was used for DNA robotic extraction. Similarly, 200 l of male urine was subjected to this automated DNA extraction (MagNA Pure LC instrument; Roche Diagnostics, Indianapolis, IN). The BTUB PCR assay design was based on fluorescent resonance energy transfer (FRET) probe chemistry (Roche Diagnostics). The use of positive and negative controls, the thermocycling protocol, data analysis, and specific sequences of primers and probes using the Roche LightCycler Instrument were previously published (9).TMA for T. vaginalis. The SOVS were placed in specimen transport medium (Gen-Probe), and male urine was pipetted i...

Comparison of Aptima Trichomonas vaginalis Transcription-Mediated Amplification Assay and BD Affirm VPIII for Detection of T. vaginalis in Symptomatic Women: Performance Parameters and Epidemiological Implications

“…Previous studies compared the ATV assay with nonmolecular assays for T. vaginalis detection, such as wet mount microscopy and culture, and showed that the ATV assay exhibited superior performance (15,17,(22)(23)(24). Other studies have shown that ATV performance is comparable to that of noncommercial PCR assays (12,24). This study is the first comparing the ATV assay side by side with another commercially available molecular assay (BD Affirm VPIII assay) for T. vaginalis detection.…”

Three-Year History of Transcription-Mediated Amplification-Based Trichomonas vaginalis Analyte-Specific Reagent Testing in a Subacute Care Patient Population

“…A paucity of studies has examined the role of laboratory diagnosis for management of trichomoniasis in men (2,12,25,28). One of these studies (28) utilized DNA amplification technology to demonstrate detection of T. vaginalis in a greater proportion of asymptomatic males (51.4%) than in those with symptoms (23%; P ϭ 0.009).…”

“…After the introduction of clinical T. vaginalis ASR screening, subsequent validation of female urine specimens, along with male urethral and urine specimens (12), was completed. The present report describes findings from a 3-year audit of clinical T. vaginalis ASR (subsequently marketed as the APTIMA Trichomonas vaginalis assay with U.S. Food and Drug Administration indications for female urine and genital swab testing) screening of a largely subacute care demographic.…”

Prevalence of Trichomonas vaginalis and Coinfection with Chlamydia trachomatis and Neisseria gonorrhoeae in the United States as Determined by the Aptima Trichomonas vaginalis Nucleic Acid Amplification Assay

“…ATV was highly specific for T. vaginalis (Ն98.9%) (28). Additional U.S. studies demonstrated that ATV has the highest sensitivity (Ͼ95%) in vaginal fluid of the available assays, including PCR, and has similarly high sensitivity in other sample types (urine, ES, and PCyt) (3,13,16,18,25). Andrea and Chapin demonstrated that the sensitivity of Affirm was only 64% in a comparison with ATV (3).…”