Necrotizing fasciitis

OBJECTIVE To describe the defining characteristics and treatment of necrotizing fasciitis (NF), emphasizng early diagnostic indications.

QUALITY OF EVIDENCE PubMed was searched using the terms necrotizing fasciitis and necrotizing soft tissue infections, paired with early diagnosis. Results were limited to human studies in English. Additional articles were obtained from references within articles. Evidence is levels II and III.

MAIN MESSAGE Necrotizing fasciitis is classified according to its microbiology (polymicrobial or monomicrobial), anatomy, and depth of infection. Polymicrobial NF mostly occurs in immunocompromised individuals. Monomicrobial NF is less common and affects healthy individuals who often have a history of trauma (usually minor). Patients with NF can present with symptoms of sepsis, systemic toxicity, or evidence of skin inflammation, with pain that is disproportional to the degree of inflammation. However, these are also present in less serious conditions. Hyperacute cases present with sepsis and quickly progress to multiorgan failure, while subacute cases remain indolent, with festering soft-tissue infection. Because the condition is rare with minimal specific signs, it is often misdiagnosed. If NF is suspected, histology of tissue specimens is necessary. Laboratory and radiologic tests can be useful in deciding which patients require surgical consultation. Once NF is diagnosed, next steps include early wound debridement, excision of nonviable tissue, and wide spectrum cover with intravenous antibiotics.

CONCLUSION Necrotizing fasciitis is an uncommon disease that results in gross morbidity and mortality if not treated in its early stages. At onset, however, it is difficult to differentiate from other superficial skin conditions such as cellulitis. Family physicians must have a high level of suspicion and low threshold for surgical referral when confronted with cases of pain, fever, and erythema.