Table 1.
Comparison of 60 patients with osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA), by treatment group
| Total n=60 | Daptomycin n=20 | Vancomycin n=40 | p-value | |
|---|---|---|---|---|
| Age (mean ± SD, years) | 51.7 (±16.5) | 51.5 (±15.9) | 51.9 (±16.9) | 0.9 |
| Male | 40 (67%) | 12 (60%) | 28 (70%) | 0.4 |
| White race | 40 (67%) | 14 (70%) | 26 (65%) | 0.3 |
| Body mass index (mean ± SD, kg/cm2) | 30.0 (±7.9) | 32.2 (±7.4) | 29.1 (±8.0) | 0.2 |
| Antibiotic allergy (any) | 17 (28%) | 6 (30%) | 11 (27.5%) | 0.8 |
| Penicillin allergy | 7 (12%) | 1 (5%) | 6 (15%) | 0.4 |
| Prior osteoarticular infection | 29 (48%) | 10 (50%) | 19 (48%) | 0.9 |
| Prior MRSA infection | 27 (45%) | 10 (50%) | 17 (43%) | 0.6 |
| Diabetes mellitus | 24 (40%) | 4 (20%) | 20 (50%) | 0.03 |
| Rheumatoid arthritis | 2 (3%) | 1 (5%) | 1 (3%) | 1.0 |
| Peripheral vascular disease | 7 (12%) | 0 (0%) | 7 (18%) | 0.08 |
| Degenerative joint disease | 2 (3%) | 0 (0%) | 2 (5%) | 0.5 |
| Renal insufficiency | 8 (13%) | 1 (5%) | 7 (18%) | 0.2 |
| Human immunodeficiency virus infection | 1 (2%) | 0 (0%) | 1 (3%) | 1.0 |
| Current cancer | 2 (3%) | 1 (5%) | 1 (3%) | 1.0 |
| Immunosuppression (steroids, immune-modulators, chemotherapy) | 3 (5%) | 0 (0%) | 3 (8%) | 0.5 |
| Current or former smoker | 34 (57%) | 12 (60%) | 22 (55%) | 0.7 |
| Orthopedic hardware present on admission | 34 (57%) | 16 (80%) | 18 (45%) | 0.01 |
| Osteomyelitis | 49 (82%) | 16 (80%) | 33 (83%) | 1.0 |
| Septic arthritis | 11 (18%) | 4 (20%) | 7 (18%) | 1.0 |
| Fever on admission (>38.3° Celsius) | 9 (15%) | 3 (15%) | 6 (15%) | 1.0 |
| Diagnostics on admission | ||||
| Blood cultures drawn on admission | 31 (52%) | 11 (55%) | 20 (50%) | 0.7 |
| ≥1 positive blood culture (any organism) | 7/31 (23%) | 3/11 (27%) | 4/20 (20%) | 0.7 |
| Radiography consistent with bone or joint infection | 27/43 (63%) | 10/17 (59%) | 17/26 (65%) | 0.7 |
| CT scan consistent with bone or joint infection | 9/9 (100%) | 5/5 (100%) | 4/4 (100%) | 1.0 |
| MRI consistent with bone | 7/7 (100%) | N/A | 7/7 (100%) | N/A |
| White blood cell count (mean ± SD, cells per μL) | 10.6 (±4.5) | 9.5 (±4.9) | 11.1 (±4.2) | 0.2 |
| Serum creatinine (median, range, mg/dL) | 0.9 (0.4–5.5) | 0.8 (0.4–5.5) | 0.9 (0.5–2.2) | 0.5 |
| ESR (median, range, mm/h) | 63 (1–119) | 55 (1–106) | 67 (4–119) | 0.8 |
| CRP (median, range, mg/dL) | 68 (1–352) | 90 (2–338) | 48 (1–352) | 0.2 |
| Study antibiotic given as part of combination antibiotic therapy | 27 (45%) | 5 (25%) | 22 (55%) | 0.03 |
| Any surgical treatment | 51 (85%) | 19 (95%) | 32 (80%) | 0.2 |
| Outcomes | ||||
| Evidence of improvement on initial follow-up | 57 (95%) | 19 (95%) | 38 (95%) | 1.0 |
| Treatment successful at 3 month follow-up | 42/60 (70%) | 15/20 (75%) | 27/40 (68%) | 0.8 |
| Treatment successful at 6 months follow-up | 37/60 (62%) | 14/20 (70%) | 23/40 (58%) | 0.5 |
NOTE. All values expressed as n (%), unless otherwise noted. SD = standard deviation, CT = computed tomography, MRI = magnetic resonance imaging, ESR = erythrocyte sedimentation rate, CRP = C-reactive protein.