TABLE 2.
Antibiotic resistance among common colonizing gram-negative bacilli, active surveillance cultures, 1 June 2009–31 May, 2012
| Organism | Total Number of Isolatesa |
MDR Isolates (% of total) |
ESBL producers (% of MDR Isolates) |
Aminoglycosides (% resistantb) |
β-lactams (% resistantb) |
Carbapenems (% resistantb) |
Fluoroquinolones (% resistantb) |
|---|---|---|---|---|---|---|---|
| Escherichia coli | 1039 | 387 (37.2) | 385 (99.5) | 69 (6.6) | 391 (37.6) | 3 (0.3) | 348 (33.5) |
| Klebsiella pneumoniae | 179 | 40 (22.3) | 40 (100) | 13 (7.3) | 40 (22.3) | 0 (0.0) | 23 (12.8) |
| Enterobacter aerogenes | 153 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 2 (1.3) | 0 (0.0) | 0 (0.0) |
| Acinetobacter calcoaceticus baumannii | 143 | 64 (44.8) | 0 (0.0) | 48 (33.6) | 52 (36.4) | 63 (44.1) | 70 (49.0) |
| Pseudomonas aeruginosa | 130 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 3 (2.3) | 1 (0.8) | 11 (8.5) |
| Enterobacter cloacae | 116 | 4 (3.4) | 4 (100) | 2 (1.7) | 12 (10.3) | 1 (0.9) | 8 (6.9) |
| Citrobacter spp. | 83 | 1 (1.2) | 1 (100) | 2 (2.4) | 2 (2.4) | 0 (0.0) | 8 (9.6) |
| Pseudomonas spp. (non-aeruginosa) | 47 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (2.1) | 0 (0.0) | 2 (4.3) |
| Proteus mirabilis | 41 | 2 (4.9) | 2 (100) | 0 (0.0) | 3 (7.3) | 0 (0.0) | 3 (7.3) |
| Serratia marcescens | 35 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (2.9) |
ESBL=extended spectrum β-lactamase; MDR=multidrug-resistant
a
Total number of isolates refers to both resistant isolates (shown here) and non-resistant isolates. In addition, an isolate may be resistant to more than one antimicrobial agent and will be counted under each applicable column.
b
The percentage reflects the proportion of organisms resistant to that antibiotic class divided by the total number of isolates of that organism