TABLE 1.
Demographic and clinical information of patients with resistant versus control isolates
| Characteristic | No. (%) unless otherwise noted |
||||
|---|---|---|---|---|---|
| All patients (n = 1,204) | ESBL cases (n = 210) | AmpC cases (n = 94) | Controls (n = 900) | P valuea | |
| Hospital | 0.91 | ||||
| West | 417 (35) | 73 (35) | 32 (34) | 312 (35) | |
| Midwest 1 | 306 (25) | 51 (24) | 27 (29) | 228 (25) | |
| Midwest 2 | 168 (14) | 27 (13) | 15 (16) | 126 (14) | |
| East | 313 (26) | 59 (28) | 20 (21) | 234 (26) | |
| Species | 0.38 | ||||
| E. coli | 1,058 (88) | 178 (85) | 89 (95) | 791 (88) | |
| K. pneumoniae | 146 (12) | 32 (15) | 5 (5) | 109 (12) | |
| Median age (range) (yr) | 5.2 (0.1–21.9) | 4.3 (0.1–20.4) | 7.7 (0.1–20.6) | 5.2 (0.1–21.9) | 0.02 |
| IQR | 1.4, 12.2 | 0.9, 10.5 | 1.9, 13.5 | 1.4, 12.5 | |
| Female | 976 (81) | 154 (73) | 73 (78) | 749 (83) | 0.006 |
| Hispanic ethnicity | 165 (14) | 25 (13) | 20 (21) | 120 (14) | 0.18 |
| Race | <0.001 | ||||
| Caucasian | 740 (64) | 110 (56) | 65 (70) | 565 (66) | |
| African-American | 270 (23) | 29 (15) | 19 (20) | 222 (26) | |
| Asian | 101 (9) | 50 (25) | 3 (3) | 48 (6) | |
| Native American | 14 (1) | 6 (3) | 0 (0) | 8 (1) | |
| Pacific Islander | 15 (1) | 3 (2) | 5 (5) | 7 (1) | |
| More than one race | 13 (1) | 0 (0) | 1 (1) | 12 (1) | |
| Site of culture | <0.001 | ||||
| Urine | 1,110 (92) | 186 (89) | 84 (89) | 840 (93) | |
| Blood | 77 (6) | 15 (7) | 7 (7) | 55 (6) | |
| Otherb | 17 (1) | 9 (4) | 3 (3) | 5 (1) | |
| Onsetc | <0.001 | ||||
| Community associated | 573 (48) | 67 (32) | 25 (26) | 481 (53) | |
| Healthcare associated | 503 (42) | 107 (51) | 58 (62) | 338 (38) | |
| Hospital associated | 128 (10) | 36 (17) | 11 (12) | 81 (9) | |
| Hospitalization (in last yr) | 357 (30) | 91 (43) | 48 (51) | 218 (24) | <0.001 |
| Medical condition category | <0.001 | ||||
| Urologicd | 317 (26) | 72 (34) | 40 (43) | 205 (23) | |
| Malignancy | 53 (4) | 17 (8) | 4 (4) | 32 (3) | |
| Other condition | 197 (16) | 44 (21) | 20 (22) | 133 (15) | |
| No condition | 634 (53) | 77 (37) | 29 (31) | 528 (59) | |
| History of Transplantation | 62 (5) | 18 (9) | 9 (10) | 35 (4) | <0.001 |
| Immunosuppression (in last yr)e | 137 (11) | 36 (17) | 17 (18) | 84 (9) | <0.001 |
| Device type | <0.001 | ||||
| Central venous catheter | 135 (11) | 40 (19) | 11 (12) | 84 (9) | |
| Foley catheter | 26 (2) | 9 (4) | 2 (2) | 15 (2) | |
| Other device | 120 (10) | 32 (16) | 18 (19) | 70 (8) | |
| No device | 922 (77) | 128 (61) | 63 (67) | 731 (81) | |
| Other antibiotic susceptibilitiesf | |||||
| Nonsusceptible to cip | 231 (19) | 150 (71) | 18 (19) | 63 (7) | <0.001 |
| Nonsusceptible to gent | 172 (14) | 103 (49) | 26 (28) | 43 (5) | <0.001 |
| Nonsusceptible to TMP-SMX | 434 (36) | 151 (72) | 46 (49) | 237 (26) | <0.001 |
| Nonsusceptible to TMP-SMX and cip | 171 (14) | 115 (55) | 16 (17) | 40 (4) | <0.001 |
| Nonsusceptible to all three | 79 (7) | 61 (29) | 7 (7) | 11 (1) | <0.001 |
| Susceptible to all three | 685 (57) | 15 (7) | 41 (44) | 629 (70) | <0.001 |
Generated comparing 3 categories of outcome for case status: ESBL producing, AmpC producing, and susceptible (controls).
Other sites of infection include the following: in ESBL cases, peritoneal fluid (n = 4), bone (n = 3), and surgical wound (n = 2); in AmpC cases, peritoneal fluid (n = 2) and cerebrospinal fluid (CSF) (n = 1); and in controls, peritoneal fluid (n = 4) and CSF (n = 1).
Definitions of onset are as follows: community associated, culture obtained in an outpatient setting or ≤48 h after hospital admission from an otherwise healthy patient without hospitalization in the previous year; healthcare associated, culture obtained in an outpatient setting or ≤48 h after hospital admission from a patient who had been hospitalized in the previous year and/or had a chronic medical condition requiring frequent health care or prolonged/recurrent antibiotic courses; and hospital associated, culture obtained >48 h after hospital admission or <48 h after hospital discharge from a patient without signs or symptoms of infection on admission.
Diagnoses included in the urologic category are congenital urological abnormality, neurogenic bladder, and vesicoureteral reflux.
Immunosuppressants included antineoplastic agents, high-dose glucocorticoids (≥2mg/kg of body weight), tumor necrosis factor inhibitors, calcineurin inhibitors, and mycophenolate mofetil.
cip, ciprofloxacin; gent, gentamicin; TMP-SMX, trimethoprim-sulfamethoxazole.