Comparison of the Alinity M STI with the GeneXpert CT/NG for the detection of sexually transmitted microorganisms

Diagn Microbiol Infect Dis. 2024 Mar;108(3):116179. doi: 10.1016/j.diagmicrobio.2024.116179. Epub 2024 Jan 4.

Abstract

We assess the performances of the Alinity M STI assay (Abbott Molecular) in comparison to the Xpert CT/NG assay (Cepheid). We first retrospectively used a collection of 70 frozen samples of which 33, 31, and 6 were positives for Chlamydia trachomatis (CT), Neisseria gonorrhoea (NG), and both micro-organisms respectively. The Alinity M STI and the Xpert CT/NG results were in accordance for all. The mean difference in cycle threshold values between the Xpert CT/NG and the Alinity M STI were -1.6 and 0.0 for CT and NG respectively. Then 214 fresh samples collected from 121 patients were prospectively tested with both instruments. Anal swabs, throat swabs, vaginal swabs, and urines accounted each for about 25%. Seven (3.2%) samples of which 5 anal swabs, provided inconclusive results with the Alinity M STI. In conclusion, the Alinity M STI is an accurate device for the microbiological diagnosis of NG and CT infections.

Keywords: Chlamydia trachomatis; Mycoplasma genitallium; Neisseria gonorrhoea; Trichomonas vaginalis.

MeSH terms

  • Chlamydia Infections* / diagnosis
  • Chlamydia trachomatis / genetics
  • Female
  • Gonorrhea* / diagnosis
  • Gonorrhea* / microbiology
  • Humans
  • Neisseria gonorrhoeae / genetics
  • Prevalence
  • Retrospective Studies
  • Sexually Transmitted Diseases* / diagnosis
  • Sexually Transmitted Diseases* / microbiology
  • Tomography, X-Ray Computed
  • Trichomonas vaginalis*