| Surgical Aspects of MRSA |
 |
 |
 |
|
Surgical Aspects of MRSA Lena Napolitano, MD, FACS, FCCP, FCCM Professor of Surgery, Division Chief, Acute Care Surgery, Associate Chair of Surgery, Department of Surgery, Director, Surgical Critical Care, University of Michigan Health System, Ann Arbor, Michigan The microbiology of skin and skin structure infections has changed considerably in recent years. Gram-positive organisms have long been recognized as the most common isolates in these serious infections. However, a marked increase in community-associated methicillin-resistant Staphylococcus aureus (MRSA) and healthcare-associated MRSA as a leading cause of complicated skin and skin structure infections has been noted over the last decade.1 Studies of patients with bacterial soft tissues infections following surgery have demonstrated high rates of MRSA-related infections.2 MRSA surgical site infections have been associated with high rates of mortality, as well as increased hospital length of stay and costs.3 The biology of diabetic foot infection is changing, and the incidence of MRSA-related skin and skin structure infections in this patient population is growing. Community-acquired MRSA infections are also a growing concern that have rapidly increased in prevalence during the last few years.4 The spectrum of disease of MRSA-related skin and soft tissue can be very broad, ranging from very minor infections that only require antimicrobial treatment to large abscesses, necrotizing infections, toxic shock syndrome, and pyomyositis. Complications of skin and skin structure infections include the spread of infection to other sites around the infected area, tissue necrosis or gangrene, and the spread of infection through the bloodstream, which may result in endocarditis, osteomyelitis, multiple new abscesses, and abscess formations at the joints, pleura, or other locations. Cases of necrotizing soft-tissue infections related to community-associated MRSA isolates in otherwise healthy patients have also been reported. The treatment of MRSA-related necrotizing soft tissue infections is similar to that of other necrotizing infections, and includes aggressive surgical debridement and broad-spectrum antimicrobial therapy. Anti-MRSA therapy should be included in the empiric treatment regimen for all patients with necrotizing soft-tissue infections given its increased prevalence. Mandatory culturing of these infections for MRSA may help to avoid the overuse of antibiotics in this setting, but is often not performed. The approach to treatment for skin and skin structure infections in general has been modified in recent years. Rather than beginning with narrow-spectrum antimicrobials, we now start with broad empiric antimicrobial coverage including coverage for MRSA, and then de-escalation of antimicrobial therapy 2 to 3 days later when culture results become available. This approach is similar to the approach used for serious infections in critical care, such as bacteremia and pneumonia. What is most important in the treatment of complicated skin and skin structure infections is to choose the right empiric antibiotics, wound culture to enable deescalation of antimicrobial therapy, and surgical source control.5 References 1. Lowy FD. Staphylococcus aureus infections. N Engl J Med. 1998;339:520-532. 2. Taylor MD, Napolitano LM. Methicillin-resistant Staphylococcus aureus infections in vascular surgery: increasing prevalence. Surg Infect (Larchmt). 2004;5:180-187. 3. Kaye KS, Engemann JJ, Mozaffari E, Carmeli Y. Reference group choice and antibiotic resistance outcomes. Emerg Infect Dis. 2004;10:1125-1128. 4. Crum NF, Lee RU, Thornton SA, et al. Fifteen-year study of the changing epidemiology of methicillin-resistant Staphylococcus aureus. Am J Med. 2006;119:943-951. 5. Grayson ML. The treatment triangle for staphylococcal infections. N Engl J Med. 2006;355:724-727.
|