TABLE 3.
Resistance rates to the different antibiotic classes
| Antibiotic families | Total n/available isolates n (%)a | Cases n/available isolates n (%)a | Controls n/available isolates n (%)a | P value |
|---|---|---|---|---|
| Cephalosporins | 95/129 (73.6) | 37/44 (84.1) | 58/85 (68.2) | 0.053 |
| Cefepime | 70/103 (68) | 34/39 (87.2) | 36/64 (56.3) | 0.001 |
| Ceftazidime | 78/128 (60.9) | 28/43 (65.1) | 50/85 (58.8) | 0.49 |
| Piperacillin-tazobactam | 93/127 (73.2) | 35/42 (83.3) | 58/85 (68.2) | 0.071 |
| Carbapenems | 82/128 (64.1) | 35/43 (81.4) | 47/85 (55.3) | 0.004 |
| Imipenem | 90/122 (73.8) | 35/38 (92.1) | 55/84 (65.5) | 0.002 |
| Meropenem | 82/123 (66.7) | 35/41 (85.4) | 47/82 (57.3) | 0.002 |
| Doripenem | 15/19 (78.9) | 7/8 (87.5) | 8/11 (72.7) | 0.60 |
| Aztreonam | 59/77 (76.6) | 26/28 (92.9) | 33/49 (67.3) | 0.011 |
| Aminoglycosides | 74/109 (67.9) | 30/41 (73.2) | 44/68 (64.7) | 0.35 |
| Gentamycin | 65/118 (55.1) | 28/41 (68.3) | 37/77 (48.1) | 0.035 |
| Amikacin | 31/121 (25.6) | 9/37 (24.3) | 22/84 (26.2) | 0.82 |
| Tobramycin | 56/98 (57.1) | 25/39 (64.1) | 31/59 (52.5) | 0.25 |
| Fluoroquinolones | 102/129 (79.1) | 40/44 (90.9) | 62/85 (72.9) | 0.017 |
| Ciprofloxacin | 95/127 (74.8) | 36/42 (85.7) | 59/85 (69.4) | 0.036 |
| Levofloxacin | 58/74 (78.4) | 23/25 (92) | 35/49 (71.4) | 0.042 |
| Fosfomycin | 23/48 (47.9) | 7/21 (33.3) | 16/27 (59.3) | 0.074 |
| Colistin | 0/113 | 0/36 | 0/77 | –b |
a
In vitro susceptibility was determined according to the EUCAST recommendations in all centers from Europe. In the centers from the United States, CLSI breakpoints were used.
b
A P value was not obtained because there were no cases of colistin resistance in any of the two groups.