TABLE 1.
Summary of ceftazidime-avibactam activities against Gram-negative organisms isolated from patients with UTIs in U.S. hospitals in 2012 to 2014
| Organism(s) (no. of isolates) or phenotypea | No. of isolates (cumulative %) inhibited at a ceftazidime-avibactam MIC (μg/ml) of: |
MIC50 (μg/ml) | MIC90 (μg/ml) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.03 | 0.06 | 0.12 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | >32 | |||
| Enterobacteriaceae (6,773) | 1,307 (19.3) | 2,382 (54.5) | 2,115 (85.7) | 616 (94.8) | 247 (98.4) | 72 (99.5) | 23 (99.8) | 7 (99.9) | 1 (>99.9) | 1 (>99.9) | 1 (>99.9) | 1 (100.0) | 0.06 | 0.25 |
| E. coli (2,876) | 508 (17.7) | 1,169 (58.3) | 995 (92.9) | 172 (98.9) | 27 (99.8) | 1 (99.9) | 2 (99.9) | 2 (100.0) | 0.06 | 0.12 | ||||
| With ESBL phenotype (330) | 24 (7.3) | 53 (23.3) | 159 (71.5) | 74 (93.9) | 15 (98.5) | 1 (98.8) | 2 (99.4) | 2 (100.0) | 0.12 | 0.25 | ||||
| Klebsiella spp. (1,484) | 116 (7.8) | 561 (45.6) | 544 (82.3) | 145 (92.0) | 77 (97.2) | 29 (99.2) | 10 (99.9) | 1 (99.9) | 0 (99.9) | 0 (99.9) | 0 (99.9) | 1 (100.0) | 0.12 | 0.25 |
| With ESBL phenotype (207) | 12 (5.8) | 12 (11.6) | 45 (33.3) | 38 (51.7) | 61 (81.2) | 27 (94.2) | 10 (99.0) | 1 (99.5) | 0 (99.5) | 0 (99.5) | 0 (99.5) | 1 (100.0) | 0.25 | 1 |
| Non-MEM-susceptible K. pneumoniae (74) | 6 (8.1) | 1 (9.5) | 4 (14.9) | 8 (25.7) | 30 (66.2) | 14 (85.1) | 9 (97.3) | 1 (98.6) | 0 (98.6) | 0 (98.6) | 0 (98.6) | 1 (100.0) | 0.5 | 2 |
| P. mirabilis (493) | 320 (64.9) | 160 (97.4) | 9 (99.2) | 3 (99.8) | 0 (99.8) | 1 (100.0) | 0.03 | 0.06 | ||||||
| Providencia spp. (373) | 92 (24.7) | 90 (48.8) | 97 (74.8) | 53 (89.0) | 26 (96.0) | 5 (97.3) | 6 (98.9) | 2 (99.5) | 1 (99.7) | 1 (100.0) | 0.12 | 0.5 | ||
| E. cloacae (356) | 6 (1.7) | 24 (8.4) | 147 (49.7) | 102 (78.4) | 48 (91.9) | 23 (98.3) | 3 (99.2) | 2 (99.7) | 0 (99.7) | 0 (99.7) | 0 (99.7) | 1 (100.0) | 0.25 | 0.5 |
| Non-CAZ susceptible (83) | 1 (1.2) | 5 (7.2) | 25 (37.3) | 28 (71.1) | 19 (94.0) | 2 (96.4) | 2 (98.8) | 0 (98.8) | 0 (98.8) | 0 (98.8) | 1 (100.0) | 0.5 | 1 | |
| Morganella morganii (305) | 132 (43.3) | 113 (80.3) | 32 (90.8) | 16 (96.1) | 7 (98.4) | 5 (100.0) | 0.06 | 0.12 | ||||||
| Proteus vulgaris (219) | 104 (47.5) | 97 (91.8) | 12 (97.3) | 2 (98.2) | 4 (100.0) | 0.06 | 0.06 | |||||||
| Citrobacter freundii (204) | 6 (2.9) | 28 (16.7) | 111 (71.1) | 38 (89.7) | 17 (98.0) | 3 (99.5) | 1 (100.0) | 0.12 | 0.5 | |||||
| Enterobacter aerogenes (189) | 8 (4.2) | 58 (34.9) | 72 (73.0) | 30 (88.9) | 19 (98.9) | 2 (100.0) | 0.12 | 0.5 | ||||||
| Citrobacter koseri (150) | 15 (10.0) | 78 (62.0) | 39 (88.0) | 15 (98.0) | 2 (99.3) | 1 (100.0) | 0.06 | 0.25 | ||||||
| S. marcescens (124) | 4 (3.2) | 57 (49.2) | 40 (81.5) | 20 (97.6) | 2 (99.2) | 1 (100.0) | 0.25 | 0.5 | ||||||
| P. aeruginosa (442) | 2 (0.5) | 20 (5.0) | 165 (42.3) | 148 (75.8) | 65 (90.5) | 32 (97.7) | 6 (99.1) | 2 (99.5) | 2 (100.0) | 2 | 4 | |||
| Non-CAZ susceptible (52) | 3 (5.8) | 12 (28.8) | 11 (50.0) | 17 (82.7) | 5 (92.3) | 2 (96.2) | 2 (100.0) | 4 | 16 | |||||
| Non-MEM susceptible (84) | 5 (6.0) | 18 (27.4) | 31 (64.3) | 22 (90.5) | 4 (95.2) | 2 (97.6) | 2 (100.0) | 4 | 8 | |||||
| Non-P-T susceptible (75) | 4 (5.3) | 14 (24.0) | 23 (54.7) | 26 (89.3) | 5 (96.0) | 2 (98.7) | 1 (100.0) | 4 | 16 | |||||
| Non-CAZ, -MEM, or -P-T susceptible (27) | 1 (3.7) | 0 (3.7) | 6 (25.9) | 14 (77.8) | 3 (88.9) | 2 (96.3) | 1 (100.0) | 8 | 32 | |||||
| Acinetobacter spp. (57) | 3 (5.3) | 3 (10.5) | 14 (35.1) | 8 (49.1) | 9 (64.9) | 10 (82.5) | 10 (100.0) | 16 | >32 | |||||
a
Abbreviations: ESBL, extended-spectrum β-lactamase; CAZ, ceftazidime; MEM, meropenem; P-T, piperacillin-tazobactam.