Necrotizing soft tissue infections: Review and current concepts in treatment, systems of care, and outcomes

Abstract

Necrotizing soft tissue infections (NSTIs) rank among the more difficult disease processes encountered by physicians and surgeons. NSTIs can arise primarily in the dermis and epidermis, but they more commonly affect the deeper layers of adipose tissue, fascia, or muscle. NSTIs are typically caused by toxin-producing bacteria and are characterized clinically by very rapid progression of disease with significant local tissue destruction. Varying amounts of early or late systemic toxicity depend on the strain of bacteria and toxins produced. Once symptomatic, the progression of disease is typically measured in hours; early diagnosis and treatment are crucial to survival. Diagnosis is hindered by the fact that the disease progresses below the surface, and the cutaneous manifestations belie the severity of disease. As the infection disseminates, patients develop pain and signs of systemic toxicity disproportionate to the findings of skin examination, and physicians must maintain a high index of suspicion to rapidly diagnose NSTIs. The standard treatment consists of broad-spectrum antibiotics, wide surgical debridement, and supportive care. Most patients require multiple surgical debridements, and survivors often have large and complex wounds requiring soft tissue coverage and prolonged hospitalizations. Even with optimal treatment, NSTIs portend significant morbidity and have mortality rates of 25%-35% in recent series. In this review, we provide historical context; discuss the epidemiology, etiology, and pathogenesis of disease; summarize the major microbiology; and elaborate the clinical presentation and diagnosis of disease with a special discussion of NSTIs in immune-compromised patients. We then outline the major and novel treatment strategies, organized by phase of treatment and with special emphasis on the importance of multidisciplinary care teams. Finally, we summarize the information on in-hospital outcomes and close with a brief discussion of posthospital and developing information on long-term quality of life and functional outcomes.