Necrotizing soft tissue infections. Clinical diagnosis and therapy decisions

Necrotizing skin and soft tissue infections (NSSTIs) are a group of rare infections with a diversity of clinical presentations. These range from superficial skin necrosis without systemic inflammatory reactions up to the classical necrotizing fasciitis with a foudroyant septic clinical course. An internationally consistent classification of NSSTIs is non-existent. These infections are characterized by the clinical and histological picture of necrosis of the involved soft tissues, which is triggered by monomicrobial and polymicrobial infections. The clinical course is characterized by subacute inflammatory reactions up to foudroyant septic progression. Crucial for the prognosis of these foudroyant septic infections is the early and correct assessment, diagnosis and therapy. This initial assessment takes place when there is still no knowledge of the pathogens, the depth of soft tissue layers involved and without histological confirmation of the diagnosis; nevertheless, this intial decision sets the course for the outcome and prognosis of these patients. This article describes the practical aspects of the clinical diagnosis of NSSTIs, the differential diagnosis, prognostic factors and therapeutic options.