Cellulitis and erysipelas

Cellulitis and erysipelas can usually be diagnosed based on history and examination only, although blood cultures and microscopic examination of cutaneous aspirates, biopsies, or swabs should be considered for selected patients, including those who are immunocompromised.

Prior episodes, preexisting lymphedema or venous insufficiency, diabetes, obesity, and tinea pedis can all predispose to cellulitis.

Antibiotics targeted at the most common etiologies (streptococci and Staphylococcus aureus) usually result in resolution.

Cellulitis is an acute spreading infection of the skin with visually indistinct borders that principally involves the dermis and subcutaneous tissue.[1]Gunderson CG. Cellulitis: definition, etiology, and clinical features. Am J Med. 2011 Dec;124(12):1113-22. http://www.ncbi.nlm.nih.gov/pubmed/22014791?tool=bestpractice.com It is characterized by erythema, edema, warmth, and tenderness, and most commonly occurs in the legs.

Erysipelas is a distinct form of superficial cellulitis with notable lymphatic involvement and is raised, sharply demarcating it from uninvolved skin.[1]Gunderson CG. Cellulitis: definition, etiology, and clinical features. Am J Med. 2011 Dec;124(12):1113-22. http://www.ncbi.nlm.nih.gov/pubmed/22014791?tool=bestpractice.com

Animal bites (including human bites), surgical wound infections, diabetic foot infections, and cellulitis or erysipelas in children and pregnant women are beyond the scope of this topic. See our topics "Animal bites" and "Diabetic foot infections".