Cellulitis

Cellulitis is a common bacterial skin infection, with over 14 million cases occurring in the United States annually. It accounts for approximately 3.7 billion dollars in ambulatory care costs and 650000 hospitalizations annually. Cellulitis typically presents as a poorly demarcated, warm, erythematous area with associated edema and tenderness to palpation. It is an acute bacterial infection causing inflammation of the deep dermis and surrounding subcutaneous tissue. The infection is without an abscess or purulent discharge. Beta-hemolytic streptococci typically cause cellulitis, generally group A streptococcus (i.e., Streptococcus pyogenes), followed by methicillin-sensitive Staphylococcus aureus. Patients who are immunocompromised, colonized with methicillin-resistant Staphylococcus aureus, bitten by animals, or have comorbidities such as diabetes mellitus may become infected with other bacteria. If the clinician correctly identifies and promptly treats cellulitis, it typically resolves with appropriate antibiotic treatment.