Summary of detection and genotyping results obtained by Public Health England (PHE) versus SpeeDx ResistancePlus kit and a breakdown of the mutations present in the specimen panel
| Initial testing | Discrepant analysis No. of SpeeDx repeats | Final results | |||
| PHE | SpeeDx | PHE | SpeeDx | ||
| Mycoplasma genitalium detection—positive | 97/97 (100%, 95% CI 96.4% to 100%) | 92/97* (94.9%, 95% CI 88.4% to 98.3%) | 5 | 97/97 (100%, 95% CI 96.4% to 100%) | 96/97† (99.0%, 95% CI 94.4% to 100%) |
| Macrolide-susceptible genotype | 21/92‡ (22.8%) | 28/92‡ (30.4%) | 11§ | 21/97 (21.7%) | 25/96¶ (26.0%) |
| Macrolide-resistant genotype | 71/92‡ (77.2%) | 64/92‡ (69.6%) | 76/97 (78.4%) | 71/96¶ (74.0%) | |
| Macrolide mutations detected | |||||
| A2058G | 25 (35.2%) | ||||
| A2059C | 7 (9.9%) | ||||
| A2059G | 38 (53.5%) | ||||
| A2059G/WT | 1 (1.4%) | ||||
*Five initial false-negative results consisted of one specimen containing an A2058T and four specimens containing A2059G mutations (Escherichia coli numbering).
†SpeeDx false-negative reconfirmed as M. genitalium positive at PHE.
‡Five detection false-negatives not included.
§Contains one mixed sample with A2058G/wild-type, one specimen which could not be reconfirmed by sequencing, one mixed sample with A2059G/wild-type sequence, four specimens genotyped as resistant by PHE and the four initial false-negative specimens.
¶SpeeDx confirmed false-negative not included in denominator.