TABLE 1.
Univariate comparison between patients acquiring Acinetobacter isolates with carbapenem MICs ≤4 mg/liter and ≥8 mg/liter
| Characteristica | Results by carbapenem MIC |
P value | |
|---|---|---|---|
| ≤4 mg/liter (n = 111) | ≥8 mg/liter (n = 113) | ||
| Demographic characteristics | |||
| Age (median [IQR]) (yr) | 74 (62–82) | 75 (58–82) | 0.676 |
| Males | 80 (72.1) | 74 (65.5) | 0.358 |
| Length of hospitalization before bacteremia (median [IQR]) (days) | 17 (9–34) | 24 (12–38) | 0.032 |
| Recent stay in ICU | 61 (55.0) | 68 (60.2) | 0.512 |
| Acquired in ICU | 53 (47.7) | 81 (71.7) | <0.001 |
| Comorbid condition | |||
| Charlson comorbidity index (median [IQR]) | 3 (2–5) | 4 (2–5) | 0.584 |
| Type 2 diabetes mellitus | 41 (36.9) | 33 (29.2) | 0.276 |
| Hypertension | 43 (38.7) | 39 (34.5) | 0.605 |
| Cerebrovascular accident | 22 (19.8) | 29 (25.7) | 0.377 |
| Chronic obstructive pulmonary disease | 19 (17.1) | 29 (25.7) | 0.163 |
| Coronary artery disease | 17 (15.3) | 18 (15.9) | 1.000 |
| Congestive heart failure | 15 (13.7) | 20 (17.7) | 0.497 |
| Alcoholism | 8 (7.2) | 7 (6.2) | 0.971 |
| Liver cirrhosis | 11 (9.9) | 7 (6.2) | 0.437 |
| Chronic kidney disease | 37 (33.3) | 41 (36.3) | 0.747 |
| Collagen vascular disease | 7 (6.3) | 5 (4.4) | 0.743 |
| Solid tumor | 35 (31.5) | 23 (20.4) | 0.079 |
| Hematological malignancy | 10 (9.0) | 8 (7.1) | 0.775 |
| Chemotherapy | 15 (13.5) | 7 (6.2) | 0.106 |
| Immunosuppressant therapy | 9 (8.1) | 10 (8.8) | 1.000 |
| Neutropenia | 5 (4.5) | 3 (2.7) | 0.497 |
| Recent surgery | 36 (32.4) | 36 (31.9) | 1.000 |
| Trauma | 2 (1.8) | 5 (4.4) | 0.446 |
| Invasive procedure | |||
| Central venous catheter | 58 (52.3) | 72 (63.7) | 0.109 |
| Endotracheal intubation or tracheostomy | 71 (64.0) | 91 (80.5) | 0.009 |
| Ventilator use | 65 (58.6) | 84 (74.3) | 0.018 |
| Hemodialysis | 11 (9.9) | 18 (15.9) | 0.253 |
| Thoracic drain | 7 (6.3) | 13 (11.5) | 0.259 |
| Abdominal drain | 11 (9.9) | 12 (10.6) | 1.000 |
| Sources of bacteremia | |||
| Pneumonia | 62 (55.9) | 60 (53.1) | 0.779 |
| Catheter | 9 (8.1) | 20 (17.7) | 0.053 |
| Urinary tract infection | 6 (5.4) | 4 (3.5) | 0.537 |
| Intra-abdominal infection | 7 (6.3) | 5 (4.4) | 0.743 |
| Wound | 6 (5.4) | 4 (3.5) | 0.537 |
| Primary bacteremia | 24 (21.6) | 21 (18.6) | 0.689 |
| Previous use of antibiotics | 71 (64.0) | 76 (67.3) | 0.705 |
| Aminoglycoside | 13 (11.7) | 9 (8.0) | 0.473 |
| Penicillin | 5 (4.5) | 1 (0.9) | 0.118 |
| β-lactam–β-lactamase inhibitors | 16 (14.4) | 8 (7.1) | 0.119 |
| Nonantipseudomonal cephalosporins | 14 (12.6) | 20 (17.7) | 0.382 |
| Antipseudomonal cephalosporins | 21 (18.9) | 22 (19.5) | 1.000 |
| Antipseudomonal carbapenems | 11 (9.9) | 25 (22.1) | 0.021 |
| Fluoroquinolone | 12 (10.8) | 15 (13.3) | 0.718 |
| Tigecycline | 2 (1.8) | 4 (3.5) | 0.683 |
| Colistin | 1 (0.9) | 6 (5.3) | 0.119 |
| Macrolide | 2 (1.8) | 5 (4.4) | 0.446 |
| Clindamycin | 9 (8.1) | 0 (0) | 0.002 |
| Vancomycin | 2 (1.8) | 6 (5.3) | 0.280 |
| Teicoplanin | 7 (6.3) | 13 (11.5) | 0.259 |
| Duration of carbapenem therapy (median [IQR]) (days) | 13 (7–16) | 9 (5.5–15) | 0.097 |
| Outcome | |||
| Shock | 42 (37.8) | 38 (33.6) | 0.604 |
| APACHE II score (median [IQR]) | 24 (17–30) | 26 (18.5–31) | 0.172 |
| 14-day mortality | 20 (18.0) | 41 (36.3) | 0.003 |
| 30-day mortality | 28 (25.2) | 60 (53.1) | <0.001 |
| Length of stay after bacteremia for survivors (median [IQR]) (days) | 28 (17–45) | 38 (19.75–64.25) | 0.196 |
| Species causative of bacteremia | |||
| A. baumannii | 50 (45.0) | 71 (62.8) | 0.011 |
| A. nosocomialis | 37 (33.3) | 36 (31.9) | 0.813 |
| A. pittii | 13 (11.7) | 6 (5.3) | 0.139 |
| Microbiological characteristics of causative microorganisms | |||
| Multidrug resistance | 47 (42.3) | 92 (81.4) | <0.001 |
| Isolates harboring genetic structure: | |||
| ISAba1-blaOXA-51-like | 16 (14.4) | 27 (23.9) | 0.103 |
| ISAba1-blaOXA-23-like | 1 (0.9) | 38 (33.6) | <0.001 |
| IS1008 (or IS1006)-ΔISAba3-blaOXA-58-like | 1 (0.9) | 12 (10.6) | 0.005 |
| blaOXA-24-like | 1 (0.9) | 8 (7.1) | 0.035 |
| blaIMP-like | 0 (0) | 5 (4.4) | 0.060 |
| blaVIM-like | 1 (0.9) | 8 (7.1) | 0.035 |
a
Data presented as number (%), unless otherwise specified. IQR, interquartile range; ICU, intensive care unit; APACHE II, Acute Physiology and Chronic Health Evaluation II.