Table 1.
Characteristics of Patients With Nosocomial Staphylococcus aureus Bacteremia (SAB) in the Invasive S. aureus Infection Cohort (INSTINCT) and S. aureus Bacteremia Group (SABG) Cohorts
| INSTINCT |
SABG |
|||||
| Characteristic | All patients (n = 304) | Patients without IE (n = 291) | Patients with IE (n = 13) | All patients (n = 432) | Patients without IE (n = 392) | Patients with IE (n = 40) |
| Age, years | ||||||
| Median (range) Interquartile range | 67 (21–91) 54–74 | 67 (21–91) 54–73 | 72 (47–86) 66–78 | 65 (15–95) 55–75 | 65 (25–95) 45–75 | 65 (15–75) 55–75 |
| Ratio of male to female patients | 103:201 | 99:192 | 4:9 | 193:239 | 171:221 | 22:18 |
| Percentage of female patients | 33.9 | 34 | 30.8 | 44.7 | 43.6 | 55 |
| Methicillin-resistant S. aureus | 47 (15.5) | 46 (15.8) | 1 (7.7) | 284 (65.7) | 252 (64.3) | 32 (80) |
| Long-term catheter present at onset | 29 (9.5) | 28 (9.6) | 1 (7.7) | 37 (8.6) | 32 (8.2) | 5 (12.5) |
| Source of bacteremia identified at onset | ||||||
| Short-term intravascular catheter | 117 (38.5) | 114 (39.2) | 3 (23.1) | 155 (35.9) | 149 (38.0) | 6 (15) |
| Long-term intravascular catheter | 23 (7.6) | 23 (7.9) | 0 | 37 (8.6) | 32 (8.2) | 5 (12.5) |
| Skin/soft tissue or wound | 33 (10.9) | 32 (11) | 1 (7.7) | 57 (13.2) | 51 (13) | 6 (15) |
| Respiratory tract | 11 (3.6) | 11 (3.8) | 0 | 57 (13.2) | 56 (14.3) | 1 (2.5) |
| Unknown | 92 (30.3) | 84 (28.9) | 8 (61.5) | 66 (15.3) | 57 (14.5) | 9 (22.5) |
| Other | 28 (9.2) | 27 (9.3) | 1 (7.7) | 60 (13.9) | 47 (12) | 13 (32.5) |
| Echocardiography within 14 days | 121 (39.8) | 111 (38.1) | 10 (76.9) | 248 (57.4) | 214 (54.6) | 34 (85) |
| TTE only | 65 (21.4) | 64 (22) | 1 (7.7) | 129 (29.9) | 117 (29.8) | 12 (30) |
| TEE only | 30 (9.9) | 29 (10) | 1 (7.7) | 41 (9.5) | 35 (8.9) | 6 (15) |
| TTE and TEE | 26 (8.6) | 18 (6.2) | 8 (61.5) | 78 (18.1) | 62 (15.8) | 16 (40) |
| Follow-up blood culture within 4 days | 171 (56.2) | 160 (55) | 11 (84.6) | 291 (67.4) | 260 (66.3) | 31 (77.5) |
| Duration of antimicrobial therapy, days | ||||||
| Median (range) Interquartile range | 14 (0–253) 9–19 | 14 (0–253) 9–18.5 | 22a (4–50) 13–33 | 17 (0–176) 12–33 | 17 (0–98) 11.8–30 | 42 (0–176) 15.5–54 |
| >14 days | 134 (44.1) | 125 (43) | 9 (69.2) | 267 (61.8) | 237 (60.5) | 30 (75) |
| >21 days | 59 (19.4) | 52 (17.9) | 7 (53.8) | 170 (39.4) | 141 (36) | 29 (72.5) |
| Late metastatic S. aureus infection or recurrent SAB | 9 (3) | 9 (3.1) | 0 | 27 (6.2) | 23 (5.9) | 4 (10) |
| 30-day case-fatality | 52 (17.1) | 48 (16.5) | 4 (30.8) | 93 (21.5) | 82 (20.9) | 11 (27.5) |
| 90-day case-fatality | 87 (28.6) | 80 (27.5) | 7 (53.8) | 125 (28.9) | 109 (27.8) | 16 (40) |
NOTE. Data are no. (%) of patients, unless otherwise indicated. TEE, transesophageal echocardiography; TTE, transthoracic echocardiography.
a
Median duration of antimicrobial therapy in patients that survived >14 days, 31 (range, 13–50 days; interquartile range, 19–37.5).