Comparison of dacron and nylon-flocked self-collected vaginal swabs and urine for the detection of Trichomonas vaginalis using analyte-specific reagents in a transcription-mediated amplification assay

Sex Transm Infect. 2012 Apr;88(3):160-2. doi: 10.1136/sextrans-2011-050084. Epub 2011 Dec 13.

Abstract

Objectives: To compare self-collected vaginal swab (SCVS) types and first-catch urine (FCU) to diagnose Trichomonas vaginalis using analyte-specific reagents designed to be used in a transcription-mediated amplification assay.

Methods: A total of 241 women (group A) collected a FCU and a SCVS using a dacron swab (APTIMA collection kit). A second group of 289 women (group B) collected two SCVS using one dacron swab and one nylon-flocked swab.

Results: Of 75 young women (street youth) determined to be infected with T vaginalis only seven reported symptoms of vaginal discharge or irritation. Using a cutoff of 50,000 relative light units, the sensitivity and specificity was 97.2% and 97.6%, respectively for dacron SCVS compared with 41.7% and 100% for FCU in group A; 92.3% and 98.8% for dacron SCVS and 92.3% and 99.2% for flocked-nylon SCVS in group B. The assay tested 96 samples in 6 h.

Conclusions: Dacron and nylon-flocked SCVS performed equally well and significantly better than FCU using analyte-specific reagents in the APTIMA transcription-mediated amplification assay. Either swab type could be used for self-collection.

MeSH terms

  • DNA, Protozoan / genetics*
  • Female
  • Humans
  • Molecular Diagnostic Techniques / methods
  • Nucleic Acid Amplification Techniques / methods
  • Nylons
  • Parasitology / methods
  • Polyethylene Terephthalates
  • Self-Examination / methods*
  • Sensitivity and Specificity
  • Specimen Handling / methods*
  • Trichomonas Vaginitis / diagnosis*
  • Trichomonas Vaginitis / parasitology
  • Trichomonas vaginalis / genetics
  • Trichomonas vaginalis / isolation & purification*
  • Urine / parasitology*
  • Vagina / parasitology*
  • Young Adult

Substances

  • DNA, Protozoan
  • Nylons
  • Polyethylene Terephthalates