French Prospective Clinical Evaluation of the Aptima Mycoplasma genitalium CE-IVD Assay and Macrolide Resistance Detection Using Three Distinct Assays.

Chloé Le Roy,Nadège Hénin,Sabine Pereyre,Cécile Bébéar,Erik Munson

doi:10.1128/jcm.00579-17

Abstract

ABSTRACTThe aim of this study was to evaluate the clinical performance of the Aptima Mycoplasma genitalium transcription-mediated amplification (MG-TMA) CE-marked for in vitro diagnosis (CE-IVD) assay for the detection of Mycoplasma genitalium in male and female clinical samples in comparison with the in-house real-time PCR (in-house PCR) assay routinely used in our laboratory. A total of 1,431 clinical specimens obtained from 1,235 patients were prospectively collected at the Bacteriology Department of Bordeaux University Hospital (France). Additional research-use-only Aptima M. genitalium transcription-mediated amplification (TMA) assays, Alt1-TMA and Alt2-TMA, were performed on discordant specimens to determine M. genitalium infection status. All confirmed M. genitalium-positive specimens were tested for macrolide resistance using three assays: the in-house 23S rRNA FRET PCR assay, the SpeeDx ResistancePlus MG assay and the nested reverse transcription-PCR (RT-PCR) sequencing assay. The comparison of the MG-TMA assay with the in-house PCR results showed a moderate correlation (kappa value, 0.69). The MG-TMA assay had higher clinical sensitivity compared to that of the in-house PCR assay (100% versus 59.74%, respectively) and similar specificity (99.10% versus 100%, respectively) for M. genitalium detection. In this study, the prevalence of M. genitalium infection was 5.90% (72/1,220 patients). The nested RT-PCR sequencing assay was the most sensitive but the most laborious assay for detecting macrolide-resistance-associated mutations. The prevalence of resistance was 8.33% (6/72). To our knowledge, this is the first clinical evaluation of the MG-TMA CE-IVD assay. The MG-TMA assay performed on the automated Panther system is a very sensitive and specific method for the detection of M. genitalium in clinical specimens.

Highlights

Mycoplasma genitalium is an important sexually transmitted organism involved in nongonococcal urethritis in men and is associated with female cervicitis and pelvic inflammatory disease in women [1,2,3]
Total of 1,431 specimens were evaluated using the Mycoplasma genitalium transcription-mediated amplification (MG-transcription-mediated amplification (TMA)) assay and the results were compared to those obtained with the in-house PCR assay routinely used for the detection of M. genitalium (Table 1)
The MG-TMA assay had a much higher sensitivity and a similar specificity compared to the in-house PCR assay for M. genitalium detection

Summary

Introduction

Mycoplasma genitalium is an important sexually transmitted organism involved in nongonococcal urethritis in men and is associated with female cervicitis and pelvic inflammatory disease in women [1,2,3]. Nucleic acid amplification tests (NAATs) that detect M. genitalium-specific nucleic acids in clinical specimens are the only available methods for diagnosis, due to the difficulties in isolating M. genitalium by culture [3]. No FDA-approved commercial assays for the detection of M. genitalium are available yet. Several NAATs based on real-time PCR or transcription-mediated amplification (TMA) have been described for the molecular detection of M. genitalium [3,4,5,6,7,8,9]. Several companies have commercialized CE-marked multiplex PCR assays for the detection of sexually transmitted pathogens, including M. genitalium [6, 7, 9, 10]. As an alternative to PCR, Hologic, Inc. developed a research-

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