TABLE 1.
Comparison of patient characteristics according to S. aureus resistance pattern and survival statusa
| Characteristic | Value(s) |
|||||
|---|---|---|---|---|---|---|
| MRSA (n = 267) | VISA (n = 87) | P value | Survivors (30 days) (n = 299) | Nonsurvivors (30 days) (n = 55) | P value | |
| Age (yr) | 56.8 ± 16.7 | 55.3 ± 16.3 | 0.479 | 55.3 ± 16.2 | 62.4 ± 17.4 | 0.003 |
| Male sex | 59.9 (160) | 64.4 (56) | 0.461 | 61.9 (185) | 56.4 (31) | 0.441 |
| White ethnicity | 63.3 (169) | 60.9 (53) | 0.691 | 61.2 (183) | 70.9 (39) | 0.171 |
| Use of vasopressors | 31.5 (84) | 28.7 (25) | 0.633 | 26.1 (78) | 56.4 (31) | <0.001 |
| Bone marrow transplant | 3.7 (10) | 2.3 (2) | 0.738 | 3.0 (9) | 5.5 (3) | 0.409 |
| Solid-organ transplant | 4.9 (13) | 1.1 (1) | 0.202 | 3.7 (11) | 5.5 (3) | 0.464 |
| Cardiovascular disease | 34.8 (93) | 31.0 (27) | 0.516 | 31.1 (93) | 49.1 (27) | 0.010 |
| Congestive heart failure | 31.8 (85) | 27.6 (24) | 0.456 | 29.1 (87) | 40.0 (22) | 0.107 |
| Chronic respiratory failure | 24.3 (65) | 27.6 (24) | 0.545 | 25.1 (75) | 25.5 (14) | 0.954 |
| Diabetes mellitus, type 2 | 36.7 (98) | 33.3 (29) | 0.569 | 36.1 (108) | 34.5 (19) | 0.823 |
| CKD/RRT | 34.5 (92) | 36.8 (32) | 0.693 | 34.4 (103) | 38.2 (21) | 0.594 |
| Solid-organ malignancy | 13.1 (35) | 19.5 (17) | 0.141 | 12.4 (37) | 27.3 (15) | 0.004 |
| Leukemia | 8.2 (22) | 8.0 (7) | 0.954 | 8.4 (25) | 7.3 (4) | 1 |
| Lymphoma | 2.2 (6) | 2.3 (2) | 0.978 | 1.7 (5) | 5.5 (3) | 0.112 |
| Cirrhosis | 2.6 (7) | 6.9 (6) | 0.066 | 2.7 (8) | 9.1 (5) | 0.036 |
| Health care exposure | 83.9 (224) | 83.9 (73) | 0.998 | 82.3 (246) | 92.7 (51) | 0.070 |
| Time to appropriate antibiotics (days) | 0.23 [0.0, 0.70] | 2.55 [0.65, 3.77] | <0.001 | 0.40 [0.0, 1.34] | 0.40 [0.7, 1.04] | 0.918 |
| Immunosuppression | 18.7 (50) | 19.5 (17) | 0.866 | 19.1 (57) | 18.2 (10) | 0.878 |
| Charlson comorbidity score | 3.7 ± 3.0 | 3.5 ± 2.9 | 0.493 | 3.4 ± 2.8 | 5.0 ± 3.5 | <0.001 |
| APACHE II score | 14.1 ± 5.6 | 13.1 ± 4.8 | 0.172 | 13.1 ± 5.1 | 17.8 ± 5.8 | <0.001 |
| Patient origin, % (n) | ||||||
| NH, SNF, or LTACH | 13.5 (36) | 5.7 (5) | 0.054 | 10.0 (30) | 20.0 (11) | 0.034 |
| Community | 44.9 (120) | 40.2 (35) | 0.441 | 46.5 (139) | 29.1 (16) | 0.017 |
| OSH | 24.3 (65) | 31.0 (27) | 0.216 | 26.4 (79) | 23.6 (13) | 0.665 |
| In hospital | 16.1 (43) | 20.7 (18) | 0.325 | 15.7 (47) | 25.5 (14) | 0.079 |
| Infection source, % (n) | ||||||
| Endocarditis | 11.6 (31) | 11.5 (10) | 0.977 | 11.7 (35) | 10.9 (6) | 0.865 |
| Hemodialysis graft or AV fistula | 2.6 (7) | 5.7 (5) | 0.177 | 3.7 (11) | 1.8 (1) | 0.700 |
| Central venous catheter | 18.7 (50) | 19.5 (17) | 0.866 | 20.4 (61) | 10.9 (6) | 0.098 |
| Unknown | 27.3 (73) | 33.3 (29) | 0.284 | 25.1 (75) | 49.1 (27) | <0.001 |
| Pneumonia/empyema | 7.9 (21) | 2.3 (2) | 0.080 | 4.3 (13) | 18.2 (10) | <0.001 |
| Discitis/osteomyelitis | 14.2 (38) | 6.9 (6) | 0.072 | 13.7 (41) | 5.5 (3) | 0.117 |
| Septic arthritis | 3.7 (10) | 4.6 (4) | 0.753 | 4.7 (14) | 0 | 0.139 |
| Skin and soft tissue infection | 5.6 (15) | 5.7 (5) | 1 | 4.7 (14) | 0 | 0.139 |
| Otherb | Not significant | Not significant | ||||
| Initial vancomycin dose (μg)c | 1,143 ± 331 | 1,198 ± 316 | 0.222 | 1,163 ± 331 | 1,117 ± 316 | 0.380 |
| Total prior vancomycin exposure, days | 0 [0.0, 2.79] | 0 [0.0, 1.85] | 0.612 | 0 [0.0, 1.96] | 0 [0.0, 2.97] | 0.123 |
| LOS (days) | 12.0 [7, 13] | 10.0 [7, 21] | 0.598 | 11 [7, 23] | 12 [6, 19] | 0.200 |
| ICU LOS (h) | 0 [0.0, 146.3] | 0 [0.0, 149.7] | 0.487 | 0 [0.0, 116.65] | 97.6 [32.7, 288.5] | <0.001 |
| 30-day all-cause mortality, % | 16.9 | 11.5 | 0.231 | |||
| MRSA | 74.2 (222) | 81.8 (45) | 0.231 | |||
| MRVISA | 17.7 (53) | 10.9 (6) | 0.213 | |||
| MSVISA | 8.0 (24) | 7.3 (4) | 1 | |||
| Any VISA | 25.8 (77) | 18.2 (10) | 0.231 | |||
| Vancomycin treated | 41.8 (125) | 43.6 (24) | 0.801 | |||
| Linezolid treated | 10.0 (30) | 23.6 (13) | 0.005 | |||
Values are expressed as means ± standard deviations, percentages (numbers of patients), or medians [interquartile ranges]. For the MRSA and VISA groups, the origins of 3 and 2 patients, respectively, could not be definitively determined based on chart review. The origins of 4 survivors and 1 nonsurvivors could not be determined. Abbreviations: CKD, chronic kidney disease; RRT, renal replacement therapy; APACHE II, acute physiology and chronic health evaluation II; NH, nursing home; SNF, skilled-nursing facility; LTACH, long-term acute-care hospital; OSH, outside hospital; LVAD, left ventricular assist device; AICD, automatic implantable cardioverter defibrillators; PPM, permanent pacemaker; LOS, length of stay; ICU LOS, intensive care unit length of stay; MRSA, methicillin-resistant Staphylococcus aureus; MRVISA, methicillin-resistant vancomycin-intermediate Staphylococcus aureus; MSVISA, methicillin-susceptible vancomycin-intermediate Staphylococcus aureus; VISA, vancomycin-intermediate Staphylococcus aureus.
Data include the following types of infections: surgical site, LVAD, prosthetic joint, traumatic wound, thrombophlebitis, urine, AICD/PPM, endovascular graft. None of these categorizations were significantly different between groups. Each of these infection types had ≤8 infections in any column (MRSA, VISA, survivors, or nonsurvivors).
A total of 229 MRSA patients, 68 VISA patients, 250 survivors, and 47 nonsurvivors received vancomycin.