[Subacute forms of necrotizing fasciitis and necrotizing cellulitis: diagnosis criteria and surgical decision-making]

Abstract

Subacute cellulitis could be described as intermediary forms between benign erysipelas and life-threatening necrotizing fasciitis with toxic shock syndrome. The key point is to consider any cellulitis a possible indication for surgery. Subacute cellulitis may occur in the elderly or diabetic patients. Local signs (cyanosis, necrosis.) are sometimes isolated. They may occur during the evolution of cellulitis requiring a medical treatment. This emphasizes the importance of carefully following-up any patient treated by antibiotics for cellulitis, i.e. monitoring the extension of erythema (using a felt-pen) and atypical local signs. Complementary investigations are especially helpful when diagnosing cellulitis requiring a surgical treatment: fine-needle aspirations; histology; soft-tissue X-ray; MR imaging that can detect alterations of the cutis and fascia, myositis, and abscesses. Surgery can be delayed for such patients, allowing for a better preparation. Sometimes, only surgical exploration may confirm cellulitis. Lastly, some cases may mimic surgical cellulitis but a prolonged course of antibiotics is able to control the disease. Abscesses requiring secondary surgical evacuation may complicate all these insidious features.