Acute bacterial skin infections and cellulitis

Purpose of review: Acute bacterial skin infections are very common, with various presentations and severity. This review focuses on deep skin infections. We separate acute nonnecrotizing infections of the hypodermis (erysipelas), forms with abscesses or exudates and necrotizing fasciitis. These three types actually differ in risk factors, bacteriology, treatment and prognosis. Recent findings: Leg erysipelas/cellulitis occurs in more than one person/1000/year. It remains mainly due to streptococci. Foot intertrigo is an important risk factor. Necrotizing fasciitis is much rarer and usually occurs in patients with chronic diseases. Staphylococci, especially community-acquired methicillin-resistant strains in some areas, play a growing role in the intermediate form of cellulitis with abscesses and exudates. For erysipelas or noncomplicated cellulitis, antibiotic treatment at home, when feasible, is much less expensive and as effective as hospital treatment. Intermediate cases with collections and exudates often require surgical drainage. For necrotizing fasciitis early surgery remains essential in order to decrease the mortality rate. Summary: Antibiotic treatment of deep skin infections must be active on streptococci; the choice of a larger spectrum of activity depends on clinical presentation, risk factors and the burden of methicillin-resistant staphylococci in the environment.