Table 1.
Relationship between clinical covariates and agr dysfunctional isolates in the overall population and stratified by LOS
| Characteristic | Results by LOS group |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Overall |
LOS of <72 h |
LOS of ≥72 h |
|||||||
| agr dysfunction (n = 63) | agr functional (n = 137) | PR (95% CI) | agr dysfunction (n = 32) | agr functional (n = 74) | PR (95% CI) | agr dysfunction (n = 31) | agr functional (n = 63) | PR (95% CI) | |
| Mean (SD) age (yr) | 61.2 (15.4) | 58.1 (17.8) | NAd | 56.8 (16.1) | 58.5 (17.1) | NA | 65.6 (13.5) | 57.7 (18.7) | NA |
| No. (%) male | 38 (60.3) | 80 (58.4) | 1.0 (0.8 to 1.3) | 18 (56.3) | 44 (59.5) | 0.9 (0.7 to 1.4) | 20 (64.5) | 36 (57.1) | 1.1 (0.8 to 1.6) |
| Median (IQR) prior length of stay (days) | 2 (0–14) | 2 (0–14) | NA | 0 (0–0) | 0 (0–1) | NA | 14 (7–34) | 15 (9–27) | NA |
| No. (%) in ICU at culture collection | 23 (36.5) | 53 (38.7) | 0.9 (0.6 to 1.4) | 2 (6.3) | 9 (12.2) | 0.5 (0.1 to 2.2) | 21 (67.7) | 44 (69.8) | 1.0 (0.7 to 1.3) |
| No. (%) with previous hospitalization within 180 days | 36 (57.1) | 66 (48.2) | 1.2 (0.9 to 1.6) | 22 (66.8) | 36 (48.6) | 1.4 (1.0 to 2.0) | 14 (45.2) | 30 (47.6) | 0.9 (0.6 to 1.5) |
| Median (IQR) no. of comorbidities | 2 (1–4) | 2 (1–3) | NA | 2 (1–3) | 2 (1–3) | NA | 3 (1–4) | 2 (1–4) | NA |
| No. (%) receiving dialysis | 15 (23.8) | 41 (29.9) | 0.8 (0.5 to 1.3) | 8 (25.0) | 25 (33.8) | 0.7 (0.4 to 1.5) | 7 (22.6) | 16 (25.4) | 0.9 (0.4 to 1.9) |
| No. (%) with diabetes mellitus | 31 (49.2) | 52 (38.0) | 1.3 (0.9 to 1.8) | 17 (53.1) | 25 (33.8) | 1.6 (1.0 to 2.5) | 14 (45.2) | 27 (42.9) | 1.1 (0.7 to 1.7) |
| No. (%) with heart failure | 25 (39.7) | 40 (29.2) | 1.4 (0.9 to 2.0) | 10 (31.3) | 18 (24.3) | 1.3 (0.7 to 2.5) | 15 (48.4) | 22 (34.9) | 1.4 (0.8 to 2.3) |
| No. (%) with chronic obstructive pulmonary disease | 20 (31.7) | 35 (25.5) | 1.2 (0.8 to 2.0) | 8 (25.0) | 15 (20.3) | 1.2 (0.6 to 2.6) | 12 (38.7) | 20 (31.7) | 1.2 (0.7 to 2.2) |
| No. (%) with hepatic dysfunction | 2 (3.2) | 8 (5.8) | 0.5 (0.1 to 2.5) | 0 (0) | 3 (4.1) | NA | 2 (6.5) | 5 (7.9) | 0.8 (0.2 to 4.0) |
| No. (%) with solid-organ transplant | 1 (1.6) | 10 (7.3) | 0.2 (0.0 to 1.7) | 1 (3.1) | 6 (8.1) | 0.4 (0.0 to 3.1) | 0 (0) | 4 (6.3) | NA |
| No. (%) with cerebrovascular disease | 8 (12.7) | 18 (13.1) | 1.0 (0.4 to 2.1) | 2 (6.3) | 9 (12.2) | 0.5 (0.1 to 2.2) | 6 (19.4) | 9 (14.3) | 1.4 (0.5 to 3.5) |
| No. (%) with HIV | 1 (1.6) | 2 (1.5) | 1.1 (0.1 to 11.8) | 1 (3.1) | 2 (2.7) | 1.2 (0.1 to 12.3) | 0 (0) | 0 (0) | NA |
| No. (%) with decubitus ulcer | 13 (20.6) | 33 (24.1) | 0.9 (0.5 to 1.5) | 7 (21.9) | 15 (20.3) | 1.1 (0.5 to 2.4) | 6 (19.4) | 18 (28.6) | 0.7 (0.3 to 1.5) |
| No. (%) with administration of immunosuppressants | 12 (19.0) | 26 (19.0) | 1.0 (0.5 to 1.9) | 7 (21.9) | 18 (24.3) | 0.9 (0.4 to 1.9) | 5 (16.1) | 8 (12.7) | 1.3 (0.5 to 3.6) |
| No. (%) with surgery <30 days prior to onset | 15 (23.8) | 38 (27.7) | 0.9 (0.5 to 1.4) | 3 (9.4) | 11 (14.9) | 0.6 (0.2 to 2.1) | 12 (38.7) | 27 (42.9) | 0.9 (0.5 to 1.5) |
| Median (IQR) CLCR (ml/min) | 55.9 (34.1–93.5) | 55 (18.0–93.5) | NA | 67.0 (25.0–97.6) | 53.6 (16.0–90.4) | NA | 52.6 (35.5–89.3) | 57.4 (23.7–104.5) | NA |
| Mean (SD) APACHE-II score at baseline | 13.8 (6.8) | 14.9 (6.9) | NA | 10.8 (5.6) | 14.3 (6.4) | NA | 16.9 (6.7) | 15.5 (7.3) | NA |
| No. (%) with prior antibiotic exposure of interest | |||||||||
| Prior antibiotic | 26 (41.3) | 33 (24.1) | 1.7 (1.1 to 2.6)a | 5 (15.6) | 9 (12.2) | 1.3 (0.5 to 3.5) | 21 (67.7) | 24 (38.1) | 1.8 (1.2 to 2.6)a |
| Prior anti-MRSA antibioticb | 9 (14.3) | 18 (13.1) | 1.1 (0.5 to 2.3) | 3 (9.4) | 7 (9.5) | 1.0 (0.3 to 3.6) | 6 (19.4) | 11 (17.5) | 1.1 (0.5 to 2.7) |
| Prior vancomycin | 3 (4.8) | 16 (11.7) | 0.4 (0.1 to 1.3) | 1 (3.1) | 6 (8.1) | 0.4 (0.0 to 3.1) | 2 (6.5) | 10 (15.9) | 0.4 (0.1 to 1.7) |
| Prior beta-lactamc | 15 (23.8) | 18 (13.1) | 1.8 (1.0 to 3.4)a | 4 (12.5) | 2 (2.7) | 4.6 (0.9 to 24.0) | 11 (35.5) | 16 (25.4) | 1.4 (0.7 to 2.6) |
| Prior fluoroquinolone | 12 (19.0) | 12 (8.8) | 2.2 (1.0 to 4.6)a | 0 (0) | 1 (1.4) | NA | 12 (38.7) | 11 (17.5) | 2.2 (1.1 to 4.4)a |
| Median no. (IQR) of prior antibiotic exposures | 0 (0–1) | 0 (0–0) | NA | 0 (0–0) | 0 (0–0) | NA | 1 (0–2)a | 0 (0–1)a | NA |
a
P < 0.05.
b
Prior anti-MRSA antibiotics received included clindamycin (n = 3), linezolid (n = 4), tetracycline (n = 1), tigecycline (n = 1), trimethoprim-sulfamethoxazole (n = 2), and vancomycin (n = 19). Some patients received more than one prior treatment with an anti-MRSA antibiotic.
c
Prior beta-lactams received included amoxicillin (n = 2), amoxicillin-clavulanate (n = 1), ampicillin-sulbactam (n = 3), aztreonam (n = 1), cefazolin (n = 9), cefepime (n = 4), ertapenem (n = 1), meropenem (n = 6), and piperacillin-tazobactam (n = 22). Some patients received more than one prior treatment with a beta-lactam.
d
NA, not able to calculate the prevalence ratio.