Community-acquired sab

Community-acquired S. aureus bacteremia, especially when an infectious focus cannot be identified, is a sign of complicated S. aureus infection. More than 40% of patients have metastatic complications. Infectious endocarditis is 3 times more common (21%) than nosocomial S. aureus bacteremia with comparable mortality. Patients with community-acquired S. aureus bacteremia are often i.v. drug abusers or have a clinically unremarkable source of bacteremia (osteomyelitis, epidural abscess).

In geriatric facilities, it is often chronic wounds(bedsores, malum perforans) in diabetic patients or chronic wounds that may be the source of S.aureus bacteremia. In elderly patients, clinical evidence of the presence of metastatic complications (joint pain) is often lacking. As risk factors, i.v. catheters are the most common source of S.aureus bacteremia, in addition to urologic catheters, orthopedic/vascular prostheses, pacemakers. Also, i.v. drug abusers, who are usually younger and have fewer comorbidities than the older patients, are at risk for bacteremia due to a high rate of skin colonization with S.aureus- and the use of non-sterile materials. Patients with nasal colonization of S. aureus are also at increased risk for S.aureus bacteremia, with decreased mortality overall (Holtfreter S et al 2006).

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