SHM's Clinical Quick Talks-Cellulitis

Pdf Summary

Cellulitis is an acute infection of the skin and deeper tissues, such as the dermis and subcutaneous fat. It can be purulent, caused by bacteria such as Staphylococcus aureus (including MRSA), or non-purulent, caused by beta-hemolytic Streptococcus (groups A, B, C, G). The exact cause of cellulitis can vary depending on factors such as immune status, antibiotic use, travel history, lifestyle, and contact with animals or humans. In most cases, an etiologic diagnosis is not necessary and empiric treatment suffices.<br /><br />The presentation of cellulitis includes rapidly spreading edema, erythema, and warmth, as well as lymphangitis, regional lymphadenopathy, and possible abscess formation. Signs of systemic toxicity, such as fever, hypotension, tachycardia, and confusion, may develop before the cutaneous findings. Laboratory tests may show elevated levels of inflammatory markers. Imaging is usually not necessary unless a deeper infection, such as an abscess or osteomyelitis, is suspected.<br /><br />The diagnosis of cellulitis is primarily based on the clinical history and physical exam findings. Attempting to identify a specific bacteria is not usually helpful, but may be considered in severe infections or with unusual exposures. Treatment of cellulitis involves choosing antibiotics based on the suspected pathogen, local resistance patterns, and severity of illness. Incision and drainage may be required for abscesses. The recommended duration of treatment is 5 days, with possible extension if there is no improvement. In cases of animal bites, tetanus vaccine should also be considered. Recurrent abscesses may require decolonization measures.<br /><br />References:<br />- Moran GJ, Abrahamian FM, LoVecchio F, Talan DA. Acute bacterial skin infections: Developments since the 2005 Infectious Disease Society of America (IDSA) guidelines. J Emerg Med. 2013;44(6):e397-e412.<br />- Gunderson CG. Cellulitis: definition, etiology, and clinical features. Am J Med. 2011;124(12):1113-22.<br />- Stevens DL, Bisno AL, Chambers HF, et al. Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Disease Society of America. Clin Infect Dis. 2014;59(2):e10-e52.

Asset Subtitle

Meghan Sebasky

Keywords

Cellulitis

acute infection

skin infection

dermis

subcutaneous fat

purulent cellulitis

non-purulent cellulitis

Staphylococcus aureus

beta-hemolytic Streptococcus

etiologic diagnosis