Evaluation of the Versant CT/GC DNA 1.0 Assay (kPCR) for the Detection of Extra-Genital Chlamydia trachomatis and Neisseria gonorrhoeae Infections

Abstract

Screening for extra-genital Chlamydia trachomatis and Neisseria gonorrhoeae infections is a crucial component for sexually transmitted diseases management, even if at present days no commercial methods have been approved for use on pharyngeal and rectal specimens by the US FDA or have received the conformity CE marking. Here we report the analytical sensitivities of the Versant CT/GC 1.0 assay (Siemens Healthcare Diagnostics, Tarrytown, NY, USA) on rectal and pharyngeal swabs, and an evaluation about the suitability for this assay with two widely used swab collection devices (E-Swab and eNAT, Copan, Brescia, Italy). The limits of detection for rectal and pharyngeal specimens with the Versant assay were 10 copies/ml and 1.0 copies/ml, for C. trachomatis and N. gonorrhoeae, respectively. False positive results due to the presence of non-gonococcal Neisseria species were excluded when clinical rectal and pharyngeal samples containing organisms identified as N. meningitidis, N. sicca, N. flavescens and N. subflava were tested. Due to its sensitivity and specificity, the Versant assay represents a good choice for the diagnosis of chlamydial and/or gonococcal infections not only in genito-urinary samples, but also on rectal and pharyngeal swabs.

Chlamydia trachomatis infection prevalence and serovar distribution in a high-density urban area in the north of Italy

“…Besides its good sensitivity and specificity, a major benefit of the Versant CT/GC DNA 1.0 assay is that the remaining eluate can be used for additional molecular tests (Bongaerst et al, 2011;Marangoni et al, 2015). Taking advantage of this opportunity, we investigated CT serovar distribution in our settings, performing a molecular genotyping assay based on omp1 gene semi-nested PCR followed by RFLP analysis.…”

“…Extra-genital samples were processed for CT DNA detection from January 2012, after a preliminary internal validation study, to assure the suitability of the molecular commercial assay for this kind of sample (Marangoni et al, 2015).…”

“…E-Swabs were preferred to eNAT for their suitability both for traditional Neisseria gonorrhoeae (GC) culture and for molecular techniques (Marangoni et al, 2015).…”

“…In fact, samples with a low starting amount of DNA (cycling threshold >36) by commercial NAATs (nucleic acid amplification tests) are usually negative by the in-house typing systems, because of the lower sensitivity of these methods, as already described (Marangoni et al, 2015;Veersteg et al, 2015).…”

Assessment of Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycobacterium tuberculosis infections in women undergoing laparoscopy: the role of peritoneal fluid sampling

“…It should be noted that APTIMA CT assay is US FDAcleared for clinical use on cervical, vaginal, and male urethral swab specimens, as well as female and male urine specimens. However, testing of additional reproductive tract specimens using a commercially available NAAT is not unadvised (18), provided that laboratories are in compliance with CLIA for test modifications (4). We are aware that all APTIMA CT test results of the present study were interpreted by clinicians within the context of the patient-specific information to determine appropriate patient management (data not shown).…”