TABLE 3.
MBL detection by DDST: results of SN, SP, PPV, and NPV stratified into seven groups according to pathogen species and MBL type produced
| Group | Ceftazidime result
|
Imipenem result
|
|||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Distance (cm) between IMBL and disk | EDTA
|
MPA
|
MAC
|
EDTA
|
MPA
|
MAC
|
|||||||||||||||||||
| SN | SP | PPV | NPV | SN | SP | PPV | NPV | SN | SP | PPV | NPV | SN | SP | PPV | NPV | SN | SP | PPV | NPV | SN | SP | PPV | NPV | ||
| General | 1.0 | 76.1 | 57.9 | 81.4 | 50 | 87 | 52.6 | 81.6 | 62.5 | 87 | 52.6 | 81.6 | 62.5 | 97.8 | 47 | 81.8 | 90 | 93.5 | 57.9 | 84.3 | 78.6 | 87 | 63.2 | 85.1 | 66.7 |
| 1.5 | 67.4 | 84.2 | 91.2 | 51.6 | 89.1 | 52.6 | 82 | 66.7 | 80.4 | 68.4 | 86 | 59.1 | 82.6 | 84.2 | 92.7 | 66.7 | 93.5 | 89.5 | 95.6 | 85 | 82.6 | 84.2 | 92.7 | 66.7 | |
| 2.0 | 45.7 | 94.7 | 95.5 | 41.9 | 87 | 84.2 | 93 | 72.7 | 82.6 | 84.2 | 92.7 | 66.7 | 50 | 94.7 | 95.8 | 43.9 | 91.3 | 84 | 93.3 | 80 | 80.4 | 94.7 | 97.4 | 66.7 | |
| 2.5 | 10.9 | 100 | 100 | 31.7 | 82.6 | 89.5 | 95 | 68 | 69.6 | 89.5 | 94.1 | 54.8 | 13 | 100 | 100 | 32.2 | 67.4 | 94.7 | 96.9 | 54.5 | 39.1 | 94.9 | 97.4 | 39.1 | |
| 3.0 | 0 | 100 | -a | 29.2 | 65.2 | 100 | 100 | 54.3 | 26.1 | 100 | 100 | 35.8 | 4.3 | 100 | 100 | 30.2 | 28.3 | 100 | 100 | 36.5 | 19.6 | 100 | 100 | 33.9 | |
| Acinetobacter spp. | 1.0 | 30 | 100 | 100 | 46.2 | 70 | 100 | 100 | 66.7 | 70 | 100 | 100 | 66.7 | 100 | 33.3 | 71.4 | 100 | 100 | 50 | 76.9 | 100 | 90 | 66.7 | 81.8 | 80 |
| 1.5 | 10 | 100 | 100 | 40 | 70 | 100 | 100 | 66.7 | 70 | 100 | 100 | 66.7 | 90 | 66.7 | 81.8 | 80 | 100 | 100 | 100 | 100 | 90 | 100 | 100 | 85.7 | |
| 2.0 | 0 | 100 | - | 37.5 | 70 | 100 | 100 | 66.7 | 60 | 100 | 100 | 60 | 60 | 100 | 100 | 60 | 100 | 100 | 100 | 100 | 90 | 100 | 100 | 85.7 | |
| 2.5 | 0 | 100 | - | 37.5 | 50 | 100 | 100 | 54.5 | 50 | 100 | 100 | 54.5 | 10 | 100 | 100 | 40 | 90 | 100 | 100 | 85.7 | 50 | 100 | 100 | 54.5 | |
| 3.0 | 0 | 100 | - | 37.5 | 20 | 100 | 100 | 42.9 | 10 | 100 | 100 | 40 | 10 | 100 | 100 | 40 | 60 | 100 | 100 | 60 | 30 | 100 | 100 | 46.2 | |
| Pseudomonas aeruginosa | 1.0 | 92.9 | 33.3 | 86.7 | 50 | 96.4 | 33.3 | 87.1 | 66.7 | 96.4 | 50 | 90 | 75 | 96.4 | 33.3 | 87.1 | 66.7 | 89.3 | 83.3 | 96.2 | 62.5 | 82.1 | 100 | 100 | 54.5 |
| 1.5 | 85.7 | 66.7 | 92.3 | 50 | 100 | 33.3 | 87.5 | 100 | 89.3 | 66.7 | 92.6 | 57.1 | 75 | 100 | 100 | 46.2 | 89.3 | 100 | 100 | 66.7 | 75 | 100 | 100 | 46.2 | |
| 2.0 | 57.1 | 100 | 100 | 33.3 | 100 | 100 | 100 | 100 | 96.4 | 100 | 100 | 85.7 | 35.7 | 100 | 100 | 25 | 85.7 | 100 | 100 | 60 | 71.4 | 100 | 100 | 42.9 | |
| 2.5 | 14.3 | 100 | 100 | 20 | 100 | 100 | 100 | 100 | 82.1 | 100 | 100 | 54.5 | 10.7 | 100 | 100 | 19.4 | 53.6 | 100 | 100 | 31.6 | 28.6 | 100 | 100 | 23.1 | |
| 3.0 | 0 | 100 | - | 17.6 | 82.1 | 100 | 100 | 54.5 | 39.3 | 100 | 100 | 26.1 | 0 | 100 | - | 17.6 | 10.7 | 100 | 100 | 19.4 | 10.7 | 100 | 100 | 19.4 | |
| Enterobacterial | 1.0 | 71.4 | 42.9 | 55.6 | 60 | 71.4 | 28.6 | 50 | 50 | 71.4 | 14.3 | 45.5 | 33.3 | 100 | 71.4 | 77.8 | 100 | 100 | 42.9 | 63.6 | 100 | 100 | 28.6 | 58.3 | 100 |
| 1.5 | 71.4 | 85.7 | 83.3 | 75 | 71.4 | 28.6 | 50 | 50 | 57.1 | 42.9 | 50 | 50 | 100 | 85.7 | 87.5 | 100.0 | 100 | 71.4 | 67.8 | 100 | 100 | 57.1 | 70 | 100 | |
| 2.0 | 57.1 | 85.7 | 80 | 66.7 | 57.1 | 57.1 | 57.1 | 57.1 | 57.1 | 57.1 | 57.1 | 57.1 | 85.7 | 85.7 | 85.7 | 85.7 | 100 | 57.1 | 70 | 100 | 100 | 85.7 | 87.5 | 100 | |
| 2.5 | 14.3 | 100 | 100 | 53.8 | 57.1 | 71.4 | 66.7 | 62.5 | 42.9 | 71.4 | 60 | 55.6 | 28.6 | 100 | 100 | 58.3 | 85.7 | 85.7 | 85.7 | 85.7 | 57.1 | 85.7 | 80 | 66.7 | |
| 3.0 | 0 | 100 | - | 50 | 57.1 | 100 | 100 | 70 | 0 | 100 | - | 50 | 14.3 | 100 | 100 | 53.8 | 57.1 | 100 | 100 | 70 | 42.9 | 100 | 100 | 63.6 | |
| IMP | 1.0 | 75 | 57.9 | 72.4 | 61.1 | 89.3 | 52.6 | 73.5 | 76.9 | 92.9 | 52.6 | 74.3 | 83.3 | 96.4 | 47.4 | 73 | 90 | 92.9 | 57.9 | 76.5 | 84.6 | 85.7 | 63.2 | 77.4 | 75 |
| 1.5 | 67.9 | 84.2 | 86.4 | 64 | 89.3 | 52.6 | 73.5 | 76.9 | 92.9 | 68.4 | 81.3 | 86.7 | 89.3 | 84.2 | 89.3 | 84.2 | 92.9 | 89.5 | 92.9 | 89.5 | 85.7 | 84.2 | 88.9 | 80 | |
| 2.0 | 50 | 94.7 | 93.3 | 56.3 | 89.3 | 84.2 | 89.3 | 84.2 | 89.3 | 84.2 | 89.3 | 84.2 | 53.6 | 94.7 | 93.8 | 58.1 | 92.9 | 84.2 | 89.7 | 88.9 | 85.7 | 94.7 | 96 | 81.8 | |
| 2.5 | 7.1 | 100 | 100 | 42.2 | 85.7 | 89.5 | 92.3 | 81 | 82.1 | 89.5 | 92 | 77.3 | 10.7 | 100 | 100 | 43.2 | 78.6 | 94.7 | 95.7 | 75 | 50 | 94.7 | 96.3 | 56.3 | |
| 3.0 | 0 | 100 | - | 40.4 | 71.4 | 100 | 100 | 70.4 | 32.1 | 100 | 100 | 50 | 7.1 | 100 | 100 | 42.2 | 39.3 | 100 | 100 | 52.8 | 28.6 | 100 | 100 | 48.7 | |
| SPM | 1.0 | 90 | 57.9 | 52.9 | 91.7 | 100 | 52.6 | 52.6 | 100 | 100 | 52.6 | 52.6 | 100 | 100 | 47.4 | 50 | 100 | 100 | 57.9 | 55.6 | 100 | 100 | 63.2 | 58.8 | 100 |
| 1.5 | 70 | 84.2 | 70 | 84.2 | 100 | 52.6 | 52.6 | 100 | 80 | 68.4 | 57.1 | 86.7 | 50 | 84.2 | 62.5 | 76.2 | 100 | 89.5 | 83.3 | 100 | 80 | 84.2 | 72.5 | 88.9 | |
| 2.0 | 30 | 94.7 | 75 | 72 | 100 | 84.2 | 76.9 | 100 | 100 | 84.2 | 76.9 | 100 | 20 | 94.7 | 66.7 | 69.2 | 90 | 84.2 | 75 | 94.1 | 70 | 94.7 | 87.5 | 85.7 | |
| 2.5 | 10 | 100 | 100 | 67.9 | 100 | 89.5 | 83.3 | 100 | 60 | 89.5 | 75 | 81 | 0 | 100 | - | 65.5 | 40 | 94.7 | 80 | 75 | 10 | 94.7 | 50 | 66.7 | |
| 3.0 | 0 | 100 | - | 65.5 | 70 | 100 | 100 | 86.4 | 10 | 100 | 100 | 67.9 | 0 | 100 | - | 65.5 | 0 | 100 | - | 66.5 | 0 | 100 | - | 65.5 | |
| VIM | 1.0 | 66.7 | 57.9 | 33.3 | 84.6 | 50 | 52.6 | 25 | 76.9 | 50 | 52.6 | 25 | 76.9 | 100 | 47.4 | 37.5 | 100 | 83.3 | 57.9 | 38.5 | 91.7 | 66.7 | 63.2 | 36.4 | 85.7 |
| 1.5 | 66.7 | 84.2 | 57.1 | 88.9 | 66.7 | 52.6 | 30.8 | 83.3 | 33.3 | 68.4 | 25 | 76.5 | 100 | 84.2 | 66.7 | 100 | 83.3 | 89.5 | 71.4 | 94.4 | 66.7 | 84.2 | 57.1 | 88.9 | |
| 2.0 | 50 | 94.7 | 75 | 85.7 | 50 | 84.2 | 50 | 84.2 | 33.3 | 84.2 | 40 | 80 | 83.3 | 94.7 | 83.3 | 94.7 | 83.3 | 84.2 | 62.5 | 94.1 | 66.7 | 94.7 | 80 | 90 | |
| 2.5 | 16.7 | 100 | 100 | 79.2 | 50 | 89.5 | 60 | 85 | 33.3 | 89.5 | 50 | 81 | 50 | 100 | 100 | 86.4 | 66.7 | 94.7 | 80 | 90 | 33.3 | 94.7 | 66.7 | 81.8 | |
| 3.0 | 0 | 100 | - | 76 | 33.3 | 100 | 100 | 82.6 | 16.7 | 100 | 100 | 79.2 | 0 | 100 | - | 76 | 16.7 | 100 | 100 | 79.2 | 16.7 | 100 | 100 | 79.2 | |
a
-, Results could not be calculated because denominator values were 0.