Community-associated Methicillin-resistant Staphylococcus Aureus (CA-MRSA) Skin Infections

Purpose Of Review: Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has become increasingly important as a cause of skin and soft tissue infections (SSTIs), particularly abscesses, in patients seen in the emergency department setting. The antibiotic sensitivity profile of Staphylococcus aureus isolates from SSTIs has changed over time in many geographic locations. Whether antibiotics are needed in the management of skin abscesses, and, if so, when, is controversial.

Recent Findings: A number of studies have looked at antibiotic therapy in conjunction with incision and drainage in managing abscesses. Factors evaluated were resolution of infection, need for change in antibiotic therapy, hospitalization after initial outpatient management, need for an additional drainage procedure, and recurrence of infection within 30 days after the initial incision and drainage procedure. For abscesses, clinical failure was associated with lack of adequate incision and drainage and not antibiotic use, regardless of the size of the abscess or the choice of antibiotic therapy. For other soft tissue infections, when antibiotic susceptibility data were available for the infection (impetigo or cellulitis with purulent drainage but no abscess), there was no difference in clinical resolution of MRSA infection even if the infecting organism was resistant to the antibiotic chosen for therapy.

Summary: CA-MRSA has become an important cause of SSTIs. Current data suggest that most abscesses can be treated successfully with incision and drainage alone. Antibiotic choice is more crucial for management of cellulitis and should be guided by the prevalence of CA-MRSA in the community and its antibiotic susceptibility profile.