Table 1. Patient demographics.
Data are displayed as median (interquartile range) and number (percentage). P values are calculated by Mann-Whitney and Fisher’s exact test respectively.
| S. aureus (n = 24) | E. coli (n = 11) | p-value | |
|---|---|---|---|
| Age | 48 (31–71) | 75 (57–83) | 0.06 |
| Male | 17 (71%) | 3 (27%) | 0.03 |
| MRSA | 4 (17%) | NA | |
| Co-morbidities | |||
| Haemodialysis | 4 (17%) | 0 (0%) | 0.28 |
| Diabetes mellitus | 6 (25%) | 1 (9%) | 0.39 |
| Acquisition a | |||
| Healthcare-associated | 12 (50%) | 2 (18%) | 0.14 |
| Source | |||
| Unknown | 7 (29%) | 1 (9%) | 0.39 |
| Central venous catheter | 6 (25%) | 0 (0%) | 0.15 |
| Peripheral venous catheter | 3 (12.5%) | 0 (0%) | 0.54 |
| Injection drug use | 5 (21%) | 0 (0%) | 0.16 |
| Diabetic foot ulcer † | 3 (12.5%) | 0 (0%) | 0.54 |
| Urinary tract | 0 (0%) | 9 (82%) | <0.001 |
| Biliary tract | 0 (0%) | 1 (9%) | 0.31 |
| Complicated S. aureus BSI b | 19 (79%) | NA | |
| Infective Endocarditis | 4 (17%) | ||
| Septic Thrombophlebitis | 5 (21%) | ||
| Haematogenous osteo-articular infection | 7 (29%) | ||
| Contiguous osteomyelitis † | 3 (12.5%) |
a Healthcare-associated infections were defined as (i) index positive blood culture collected ≥48hrs after hospital admission, and no signs or symptoms of the infection noted at time of admission; OR (ii) index positive blood culture collected <48hrs after hospital admission if any of the following criteria are met: received intravenous therapy in an ambulatory setting in the 30 days before onset of BSI, attended a hospital clinic or haemodialysis in the 30 days before onset of BSI, hospitalised in an acute care hospital for ≥ 2 days in the 90 days prior to onset of BSI, resident of nursing home or long-term care facility.
b Staphylococcus aureus bacteraemia was defined as uncomplicated if all of the following criteria were met: exclusion of endocarditis; no evidence of metastatic infection; absence of implanted prostheses; follow-up blood cultures at 2–4 days culture-negative for S. aureus; defervescence within 72 h of initiating effective therapy. Percentages shown are of entire S. aureus BSI population.
† Three patients had chronic diabetic foot ulcers as a source of their S. aureus BSI, and in all cases the contiguous underlying bone was also found to be infected.
MRSA = methicillin-resistant Staphylococcus aureus. NA = not applicable. BSI = bloodstream infection.