Community-associated methicillin-resistant Staphylococcus aureus: Incidence, clinical presentation, and treatment decisions

Abstract

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have been reported with increasing frequency from many parts of the world. Most infections involve the skin and soft tissue structures, and CA-MRSA is now the most commonly identifiable cause of purulent skin and soft tissue infections. The spectrum of disease can range from simple cutaneous abscesses to fulminant necrotizing infection. CA-MRSA strains, in contrast to healthcare-associated strains, are generally extra virulent and produce more toxins. Unlike the healthcare-associated strains, they demonstrate variable susceptibility patterns to various classes of antibiotics. Empiric antibiotic therapy for patients with purulent skin and soft tissue infection and for those presenting with severe, life-threatening infections should include an agent active against CA-MRSA.

Meeting the Challenges of Methicillin‐ResistantStaphylococcus aureuswith Outpatient Parenteral Antimicrobial Therapy

“…Table 2 shows a comparison of the clinical features of CA-MRSA infection with those of HA-MRSA infection, as well as the most effective antibiotic agents for empirical therapy [20]. The latest Infectious Diseases Society of America guidelines for the management of skin and soft-tissue infections, including those caused by multidrug-resistant organisms, recommend consideration for hospitalization of patients with hypotension, elevated creatinine level, low serum bicarbonate level, elevated creatine phosphokinase level, marked left white blood cell shift, and C-reactive protein level 113 mg/L [22,23]. Most abscesses can be incised and drained in the emergency department or outpatient clinic and treated (with or without antibiotics) on an outpatient basis, whereas some deep or extensive lesions may require hospitalization and surgical intervention [23].…”

“…Most abscesses can be incised and drained in the emergency department or outpatient clinic and treated (with or without antibiotics) on an outpatient basis, whereas some deep or extensive lesions may require hospitalization and surgical intervention [23]. Patients with infections associated with osteomyelitis, septic arthritis, and endocarditis are usually hospitalized initially [23].…”

“…Because of rifampin's ability to select resistant strains, it should not be used as monotherapy but may be of added value when used with antibiotics [23]. Long-acting tetracyclines (such as doxycycline and minocycline) may be used as alternate agents for specific types of MRSA infection, particularly those of the skin and skin structure [25].…”

“…For moderate-to-severe infections or in areas with high MRSA prevalence, empirical coverage should include TMP-SMX plus a first-generation cephalosporin or penicillinase-resistant penicillin, or alternatively, clindamycin alone [23] (linezolid and tigecycline are also available if the staphylococci are resistant to methicillin). Intravenous antibiotics are appropriate for patients with abscesses who require hospitalization, are immunocompromised, have evidence of systemic toxicity associated with significant cellulitis, or have large (у5 cm), multiple, or recurring abscesses.…”

“…At any one time, ∼10% of patients in hospitals have an HA infection [28], defined as an infection occurring 48 h after admission [23]. An equal number of hospitalized patients have infections acquired in the community.…”