Skin and skin structure infection

Types

Until 2008, a distinction was made between two types: complicated SSSIs (cSSSIs) and uncomplicated SSSIs (uSSSIs), which had different regulatory approval requirements. Uncomplicated SSSIs included "simple abscesses, impetiginous lesions, furuncles, and cellulitis." Complicated SSSIs included "infections either involving deeper soft tissue or requiring significant surgical intervention, such as infected ulcers, burns, and major abscesses or a significant underlying disease state that complicates the response to treatment." The FDA further noted that "[s]uperficial infections or abscesses in an anatomical site, such as the rectal area, where the risk of anaerobic or Gram-negative pathogen involvement is higher, [were also] considered complicated infections." The uncomplicated category (uSSSI) is most frequently caused by Staphylococcus aureus and Streptococcus pyogenes, whereas the complicated category (cSSSI) might also be caused by a number of other pathogens. As of 2013, the pathogen involved in cases of cSSSI were known about 40% of the time.