Abstract:
BACKGROUND: Genital mycoplasmas are opportunistic bacteria that are associated with undesirable gynaecologic
and reproductive events. Mycoplasmas are fastidious bacteria with increasing resistance to routine antimicrobials
and often fail to grow on conventional culture methods. The commercial Mycofast Revolution assay permits the
phenotypic detection and identification of genital mycoplasmas. Antimicrobial susceptibility testing against five
antimicrobial agents with MICs corresponding to the CLSI guidelines can also be performed. This study aimed to
compare the new commercially available Mycofast Revolution assay with a multiplex PCR assay.
METHODS: Self-collected swabs were obtained from pregnant women attending the antenatal clinic of a tertiary
academic hospital in Pretoria, South Africa from October 2012 to November 2012. These swabs were used to seed
UMMt and modified Amies transport media. The seeded UMMt transported medium was used to inoculate the
Mycofast Revolution assay for the identification, enumeration and antimicrobial susceptibility testing of genital
mycoplasmas. Following DNA extraction from the modified Amies transport medium, specimens were subjected to
a multiplex PCR assay for the detection of genital mycoplasmas.
RESULTS: The Mycofast Revolution kit had a sensitivity and specificity of 77.3% (95% CI: 62.15% to 88.51%) and 80%
(95% CI: 28.81% to 96.70%), respectively, against the PCR assay. The positive and negative predictive values were
97.1% (95% CI: 85.03% to 99.52%) and 28.6% (95% CI: 8.57% to 58.08%). Genital mycoplasmas were detected in
71.4% (35/49) of samples with the Mycofast Revolution assay with 49% (24/49) being Ureaplasma spp. and 22.4%
(11/49) mixed strains. The multiplex PCR assay had a positivity rate of 89.8% (44/49) for genital mycoplasmas; mixed
strains were present in 51% (25/49) of samples, Ureaplasma spp. in 16.3% (8/49) and M. hominis in 22.4% (11/49) of
samples.
CONCLUSIONS: There was a fair agreement (κ = 0.319) between the Mycofast Revolution assay and the mPCR assay.
With the high prevalence rates of genital mycoplasmas, fast and efficient diagnostic methods are imperative to
treat infections and minimise complications. The Mycofast Revolution assay is simple to use, has a short turnaround
time and interpretation of results are straightforward. This assay circumvents common problems
experienced with conventional culture and molecular methods in diagnostic laboratories where skilled personnel
are limited and can be used as an alternative diagnostic assay.