Rapid identification of vancomycin-resistant enterococci (VRE) can assist in choosing the appropriate treatment and preventing VRE spread. The performance of chromIDTM VRE agar was evaluated using 184 clinical isolates of Enterococcus spp. and reference strains. The test had a sensitivity of 95.52% but a low specificity of 30%.
| Species | Susceptibility to vancomycina a S, susceptible; R, resistant. | Origin | |||
|---|---|---|---|---|---|
| S | R | Infection | Surveillance culture | ||
| E. faecalis | 43 | 47 | 47 | 43 | |
| E. faecium | 7 | 87 | 75 | 19 | |
| Total | 50 | 134 | 122 | 62 | |
| ChromID™ VRE agar | Gold standard (VRE)a a Vancomycin resistance was determined using both Etest® and CLSI guidelines; C.I., confidence intervals. | Gold standard (VSE)a a Vancomycin resistance was determined using both Etest® and CLSI guidelines; C.I., confidence intervals. | Total |
|---|---|---|---|
| Test positive | 128 | 35 | 163 |
| Test negative | 6 | 15 | 21 |
| Total | 134 | 50 | 184 |
| Sensitivity | 95.52% (95% C.I. = 92.02-99.02%) | ||
| Specificity | 30.00% (95% C.I. = 17.29-42.70%) | ||
| Positive predictive value | 78.53% (95% C.I. = 72.22-84.83%) | ||
| Negative predictive value | 71.43% (95% C.I. = 52.10-90.75%) | ||
| Accuracy | 77.72% (95% C.I. = 71.70-83.73%) |
