Necrotizing soft-tissue infection of a limb: clinical presentation and factors related to mortality

Necrotizing fasciitis is a rare and often fatal soft-tissue infection. Prompt diagnosis and immediate aggressive surgical debridement of all compromised tissues are critical to reducing morbidity and mortality in these rapidly progressive infections. The purpose of this study was to analyze the clinical presentation and evaluate factors that determine mortality associated with this uncommon surgical emergency.

The study retrospectively investigated the medical records of 22 patients who were diagnosed and treated for necrotizing fasciitis of the lower extremity, 14 of whom had involvement of the foot (nine patients) or foot and ankle (five patients) at our hospital. The data collected for each of the 22 patients were age, sex, underlying systemic factors, location of infection, duration of symptoms, portal of entry of infection, initial diagnosis on admission, physical, radiographic and laboratory findings, microbiological cultures, the type of therapy used (debridement or amputation), treatment outcome, and number of days in the hospital.

A total of 23 extremities of 22 consecutive patients with necrotizing fasciitis who underwent surgical debridement or amputation were retrospectively reviewed. Radical surgical debridement was done in 16 extremities initially, and this treatment was repeated a mean of two times (range one to four debridements) to completely remove all the necrotic tissue. Nine patients (41%) required below-knee or above-knee amputation. There were three deaths, one related directly to sepsis and organ failure, one due to gastrointestinal hemorrhage, and one caused by pulmonary embolism. There were no significant differences between patients who had the amputations and those who did not with respect to mortality rate or age (p = 0.538 and p = 0.493, respectively). Those who died were significantly older than the survivors (p = 0.038).

The diagnosis of necrotizing fasciitis should be considered for any individual who has unexplained limb pain, especially if that person has diabetes mellitus or chronic liver disease. There was no difference in mortality rates between patients with or without amputation. The primary treatment is early and aggressive debridement of involved skin, subcutaneous fat, and fascia.