Antibiotic usage for methicillin-resistant Staphylococcus mycotic aneurysms.

Methicillin-resistant Staphylococcus aureus (MRSA) is increasing in incidence due to widespread use of cephalosporin antibiotics. These infections, generally, are characteristically hospital acquired and related to antibiotic pressure. The appearance of community acquired MRSA has recently been observed among IV drug abusers (IVDA). The duration and type of antibiotic therapy is controversial. Twenty patients with IVDA related mycotic aneurysms and associated soft tissue infections were evaluated. Particular attention was given to the bacteria cultured, the antibiotic therapy used and the response to therapy. Antibiotic use was inconsistent. Thirty per cent of the patients received no antibiotics. Although 62 per cent of the Staphylococcus aureus infections in this group were methicillin-resistant and quite extensive, the antibiotics used had no clinical importance. The need for vancomycin as therapy for extensive soft tissue infections with MRSA may be overrated and probably contributes to the development of increasing antibiotic resistance.