TABLE 4.
Reaction | Associated antibiotic | No. of isolates with the following result: |
Sensitivity (95% CI)b | Specificity (95% CI)b | ||||
---|---|---|---|---|---|---|---|---|
TP | FP | FN | TN | Total | ||||
penA Asp345del ± penA Gly545Ser | ESCs | 1c | 17d | 0 | 76 | 94 | 1.00 (0.03, 1.00) | 0.82 (0.72, 0.89) |
23S rRNA C2611T and/or 23S rRNA A2059G | AZM | 1 | 1 | 0 | 92 | 94 | 1.00 (0.03, 1.00) | 0.99 (0.94, 1.00) |
gyrA Ser91Phe | CIP | 41 | 1 | 0 | 52 | 94 | 1.00 (0.91, 1.00) | 0.98 (0.90, 1.00) |
16S rRNA C1192T | SPC | 0 | 2 | 0 | 92 | 94 | NA | 0.98 (0.93, 1.00) |
CI, confidence interval; TP, true positive; FP, false positive; FN, false negative; TN, true negative; ESCs, extended-spectrum cephalosporins; AZM, azithromycin; CIP, ciprofloxacin; SPC, spectinomycin; NA, not applicable.
Sensitivity and specificity were calculated on the basis of the susceptibility phenotype (MICs) of the paired culture isolates.
This isolate harbored a penA mosaic X allele and was correctly identified as ESC resistant by the penA Ala345del reaction.
Three isolates were correctly predicted to harbor a mosaic penA allele on the basis of the molecular characterization but were susceptible to ESCs.