Source: DGNews  |  Posted 2 years ago

By Ed Susman

SAN FRANCISCO -- September 17, 2009 -- Linezolid and vancomycin are clinically effective in the treatment of complicated skin and soft-tissue infections caused by both community-acquired and non-community-acquired methicillin-resistant Staphylococcus aureus (MRSA), researchers stated here at the 49th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC).

An open-label study comparing the ability of linezolid with vancomycin to treat the infections was presented here on September 14 at a poster session by Ron Jones, MD, JMI Laboratories, West Liberty, Iowa.

Dr. Jones and colleagues stratified treatment outcomes by whether patients were infected in the hospital -- usually thought to be surgical wounds -- or became infected with MRSA strains circulating within the community. "Community-acquired MRSA was more likely to be found in younger and less seriously ill patients," Dr. Jones reported.

At the end of the study endpoint, among those patients with community-acquired MRSA 98 of 116 patients (84.5%) treated with linezolid had achieved a treatment cure compared with 92 of 120 patients (76.7%) who were treated with vancomycin. The difference did not reach statistical significance (P = .13).

Among those patients with non-community-acquired MRSA, 100 of 123 patients (81.3%) treated with linezolid achieved a cure compared with 86 of 121 patients (71.1%) of those treated with vancomycin (P = .06).

Males comprised about 63% of the patients with community-acquired MRSA, and about 53% of those with non-community-acquired MRSA. The average age of the community-acquired MRSA patients was approximately 41 years compared with approximately 59 years for those with non-community-acquired MRSA. About 66% of the community-acquired MRSA patients in this sample were white; about 79% of those with non-community-acquired MRSA were white.

The predominant diagnosis for community-acquired MRSA was an abscess, which occurred in 86% of the cases, while surgical wounds (43%) were the most common cause of non-community-acquired MRSA, followed by diabetic ulcers (16%) and other skin ulcers (15%) and abscesses (10%).

[Presentation title: Correlation of Baseline Methicillin-Resistant Staphylococcus aureus (MRSA) Isolate Characteristics With Clinical Outcome From a Randomized Phase 4 Clinical Trial of Complicated Skin and Soft Tissue Infections (cSSTI). Abstract L1-1673]