Epidemiology and etiology

Necrotizing fasciitis (NF) is an uncommon, rapidly progressive, life-threatening infection that causes necrosis of the subcutaneous tissue and fascia. When due to GAS in-

fection, its associated mortality rate approaches 25%. NF can affect any age group.

Although the risk of NF is higher in injection drug users and in patients with diabetes,

immune suppression, or obesity, healthy hosts can become infected as well.

NF typically erupts after an initial trauma, which can range from a small abrasion to a deep penetrating wound. The infection begins in the fascia, where bacteria rep-

licate and release toxins that facilitate their spread.

In approximately 70% of cases, NF is polymicrobial and typically involves anaerobes (i.e., Bacteroides or Pepto-streptococcus), facultative anaerobes (i.e., P-hemo-

lytic streptococci), and Enterobacteriaceae (e.g., Escherichia coli, Enterobacter, Kleb-

siella). P. aeruginosa is occasionally implicated as well. Polymicrobial NF develops in the following clinical settings: after surgery or deep penetrating wounds involving the bowel; from decubitous ulcer, perianal, or vulvovaginal infection; or from the injection site in an IV drug user.1,8

The remaining 30% are monomicrobial, caused by invasive GAS, or less frequently, Clostridium perfringens. CA-MRSA is more recently being implicated in these infections as well. 4 Monomicrobial NF is generally more severe than polymicrobial NF. GAS NF often occurs after minor trauma, such as an insect bite or abrasion, whereas infection with C. perfringens typically develops from surgical or traumatic wounds.1,26 Once introduced, these organisms produce toxins that induce systemic toxicity, multiorgan failure, and shock.26,27 Clostridial myonecrosis is more commonly known as gas gangrene.1,26

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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