TABLE 4.
Use of known resistant isolates to test performance of CPE screening methodsa
| Method | Overall sensitivity (%) | Sensitivity (%) by β-lactamase class (no. of isolates tested) |
Specificity (%) (no. of negative isolates tested | Type(s) of isolates | Reference | ||
|---|---|---|---|---|---|---|---|
| Class A | Class B | Class D | |||||
| Supercarba | 95.6 | 100 (18) | 90 (52) | 100 (44) | 82.2 (62) | CLI | 149 |
| chromID ESBL | 87.7 | 100 (18) | 98 (52) | 70 (44) | 24.2 (62) | ||
| CHROMagar KPC | 40.3 | 66.7 (18) | 55.8 (52) | 13.6 (44) | 85.5 (62) | ||
| Supercarba | 96.5 | 100 (20) | 92 (51) | 100 (43) | 60.7 (28) | CLI | 143 |
| CHROMagar KPC | 43 | 70 (20) | 58.8 (51) | 11.6 (43) | 67.8 (28) | ||
| Brilliance CRE | 76.3 | 85 (20) | 78.4 (51) | 69.8 (43) | 57.1 (28) | ||
| Brilliance CRE | 86 | 100 (17) | 72 (25) | 88 (58) | 40 (77) | CLI | 147 |
| Colorex KPC | 48 | 100 (17) | 52 (25) | 31 (58) | 39 (77) | ||
| Supercarba | 97 | 100 (17) | 88 (25) | 100 (58) | 35 (77) | ||
| Brilliance CRE | 78 | 83 (12) | 79 (103) | 67 (15) | 66 (70) | CLI | 144 |
| chromID Carba | 91 | 100 (12) | 93 (103) | 67 (15) | 89 (70) | ||
| chromID ESBL | 96 | 100 (12) | 98 (103) | 80 (15) | 19 (70) | ||
| Colorex KPC | 56 | 83 (12) | 52 (103) | 60 (15) | 77 (70) | ||
| CDC protocol for ertapenem | 78 | 83 (12) | 80 (103) | 73 (15) | 69 (70) | ||
| CDC protocol for meropenem | 47 | 67 (12) | 46 (103) | 40 (15) | 79 (70) | ||
| Brilliance CRE | 94 | 100 (36) | 94 (34) | 84 (25) | 71 (160) | CLI, CCI | 146 |
| mHT | 100 | 100 (18) | ND (0) | ND (0) | 96.7 (32) | CCI | 110 |
| RambaChrom KPC | 95 | 95 (18) | ND (0) | ND (0) | 77.1 (32) | ||
| Mero-PBA-DDST | 100 | 100 (18) | ND (0) | ND (0) | 100 (32) | ||
| Erta-PBA-DDST | 100 | 100 (18) | ND (0) | ND (0) | 91.4 (32) | ||
a
CCI (characterized clinical isolate) is an isolate originating from a clinical specimen and later characterized in the laboratory. CLI (characterized laboratory isolate) is an isolate retrieved from a laboratory source. It may have originated from a clinical specimen but may have been modified to express certain characteristics in the laboratory. ND, not determined; mHT, modified Hodge test; PBA-DDST, phenylboronic acid double-disk synergy test; Mero, meropenem; Erta, ertapenem.