Table 3.
MIC Distribution of Colistin Between 2015 and 2017 in IAI, RTI and UTI Isolates
| Isolates (n, %) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| IAI | UTI | RTI | ||||||||||
| Total | MIC (mg/L) | Total | MIC (mg/L) | Total | MIC (mg/L) | |||||||
| ≤1* | 2–4* | >4* | ≤1* | 2–4* | >4* | ≤1* | 2–4* | >4* | ||||
| All Enterobacterales | 3251 (100.0) | 2795 (86.0) | 121 (3.7) | 335 (10.3) | 2483 (100.0) | 2154 (86.7) | 100 (4.0) | 229 (9.2) | 1379 (100.0) | 1108 (80.3) | 85 (6.2) | 186 (13.5) |
| CR-Enterobacterales | 462 (100.0) | 320 (69.3) | 28 (6.1) | 114 (24.7) | 248 (100.0) | 163 (65.7) | 20 (8.1) | 65 (26.2) | 360 (100.0) | 286 (79.4) | 20 (5.6) | 54 (15.0) |
| CS-Enterobacterales | 2548 (100.0) | 2335 (91.6) | 83 (3.3) | 130 (5.1) | 2051 (100.0) | 1893 (92.3) | 74 (3.6) | 84 (4.1) | 925 (100.0) | 783 (84.6) | 61 (6.6) | 81 (8.8) |
| Escherichia coli | 1722 (100.0) | 1605 (93.2) | 59 (3.4) | 58 (3.4) | 1742 (100.0) | 1619 (92.9) | 64 (3.7) | 59 (3.4) | 193 (100.0) | 171 (88.6) | 19 (9.8) | 3 (1.6) |
| CR-Escherichia coli | 138 (100.0) | 112 (81.2) | 6 (4.3) | 20 (14.5) | 89 (100.0) | 64 (71.9) | 8 (9.0) | 17 (19.1) | 27 (100.0) | 24 (88.9) | 2 (7.4) | 1 (3.7) |
| CS-Escherichia coli | 1524 (100.0) | 1442 (94.6) | 49 (3.2) | 33 (2.2) | 1586 (100.0) | 1502 (94.7) | 53 (3.3) | 31 (2.0) | 163 (100.0) | 144 (88.3) | 17 (10.4) | 2 (1.2) |
| Klebsiella pneumoniae | 884 (100.0) | 802 (90.7) | 39 (4.4) | 43 (4.9) | 430 (100.0) | 374 (87.0) | 28 (6.5) | 28 (6.5) | 836 (100.0) | 746 (89.2) | 48 (5.7) | 42 (5.0) |
| CR-Klebsiella pneumoniae | 193 (100.0) | 160 (82.9) | 13 (6.7) | 20 (10.4) | 95 (100.0) | 73 (76.8) | 9 (9.5) | 13 (13.7) | 246 (100.0) | 218 (88.6) | 11 (4.5) | 17 (6.9) |
| CS-Klebsiella pneumoniae | 657 (100.0) | 617 (93.9) | 22 (3.3) | 18 (2.7) | 307 (100.0) | 276 (89.9) | 17 (5.5) | 14 (4.6) | 565 (100.0) | 512 (90.6) | 35 (6.2) | 18 (3.2) |
| Enterobacter cloacae | 243 (100.0) | 165 (67.9) | 10 (4.1) | 68 (28.0) | 69 (100.0) | 55 (79.7) | 5 (7.2) | 9 (13.0) | 95 (100.0) | 68 (71.6) | 8 (8.4) | 19 (20.0) |
| CR-Enterobacter cloacae | 37 (100.0) | 22 (59.5) | 4 (10.8) | 11 (29.7) | 17 (100.0) | 16 (94.1) | 1 (5.9) | 0 (0.0) | 18 (100.0) | 13 (72.2) | 4 (22.2) | 1 (5.6) |
| CS-Enterobacter cloacae | 162 (100.0) | 117 (72.2) | 4 (2.5) | 41 (25.3) | 40 (100.0) | 33 (82.5) | 3 (7.5) | 4 (10.0) | 66 (100.0) | 48 (72.7) | 3 (4.5) | 15 (22.7) |
| Klebsiella aerogenes | 80 (100.0) | 74 (92.5) | 1 (1.3) | 5 (6.3) | 30 (100.0) | 26 (86.7) | 1 (3.3) | 3 (10.0) | 36 (100.0) | 33 (91.7) | 3 (8.3) | 0 (0.0) |
| CR-Klebsiella aerogenes | 11 (100.0) | 9 (81.8) | 0 (0.0) | 2 (18.2) | 2 (100.0) | 2 (100.0) | 0 (0.0) | 0 (0.0) | 3 (100.0) | 3 (100.0) | 0 (0.0) | 0 (0.0) |
| CS-Klebsiella aerogenes | 43 (100.0) | 39 (90.7) | 1 (2.3) | 3 (7.0) | 18 (100.0) | 16 (88.9) | 1 (5.6) | 1 (5.6) | 25 (100.0) | 22 (88.0) | 3 (12.0) | 0 (0.0) |
Notes: The data are expressed as n (%). *MIC breakpoint (mg/L). MIC breakpoint (mg/L) of colistin to Enterobacterales for sensitivity is ≤2; resistance is >2 according to European Committee on Antimicrobial Susceptibility Testing Breakpoint tables for interpretation of MICs and zone diameters Version 7.1, valid from 2017-03-10.
Abbreviations: MIC, minimum inhibitory concentration; IAI, intra-abdominal infection; UTI, urinary tract infection; RTI respiratory tract infection; CS, carbapenem sensitive; CR, carbapenem-resistant.