-
Archives
- April 2012
- March 2012
- February 2012
- January 2012
- December 2011
- November 2011
- October 2011
- September 2011
- August 2011
- July 2011
- June 2011
- May 2011
- April 2011
- March 2011
- February 2011
- January 2011
- December 2010
- November 2010
- October 2010
- September 2010
- August 2010
- July 2010
- June 2010
- May 2010
- April 2010
- March 2010
- February 2010
- January 2010
- December 2009
- November 2009
- October 2009
- September 2009
- August 2009
- July 2009
- June 2009
- May 2009
- April 2009
- March 2009
- February 2009
-
Meta
As far as I know it is a non common infection, but non-discriminate in where it hits.
The infection begins locally, at a site of trauma, which may be severe (such as the result of surgery), minor, or even non-apparent. The affected skin is classically, at first, very painful without any grossly visible change. With progression of the disease, tissue becomes swollen, often within hours. Diarrhea and vomiting are common symptoms as well. Inflammation does not show signs right away if the bacteria is deep within the tissue. If it is not deep, signs of inflammation such as redness and swollen or hot skin show very quickly. Skin color may progress to violet and blisters may form, with subsequent necrosis (death) of the subcutaneous tissues. Patients with necrotizing fasciitis typically have a fever and appear very ill. More severe cases progress within hours, and the mortality rate is high, about 30%. Even with medical assistance, antibiotics take a great deal of time to react to the bacteria, allowing the infection to progress to a more serious state.[1]
"Flesh-eating bacteria” is a misnomer, as the bacteria do not actually eat the tissue. They cause the destruction of skin and muscle by releasing toxins (virulence factors). These include streptococcal pyogenic exotoxins and other virulence factors. S. pyogenes produces an exotoxin known as a superantigen. This toxin is capable of activating T-cells non-specifically. This causes the over-production of cytokines that over-stimulate macrophages. The macrophages cause the actual tissue damage by releasing oxygen free radicals.
The diagnosis is confirmed by either blood cultures or aspiration of pus from tissue, but early medical treatment is crucial and often presumptive; thus, antibiotics should be started as soon as this condition is suspected. Initial treatment often includes a combination of intravenous antibiotics including penicillin, vancomycin and clindamycin. If necrotizing fasciitis is suspected, surgical exploration is always necessary, often resulting in aggressive debridement (removal of infected tissue). As in other maladies characterized by massive wounds or tissue destruction, hyperbaric oxygen treatment can be a valuable adjunctive therapy, but is not widely available. Amputation of the affected organ(s) may be necessary. Repeat explorations usually need to be done to remove additional necrotic tissue. Typically, this leaves a large open wound which often requires skin grafting. The associated systemic inflammatory response is usually profound, and most patients will require monitoring in an intensive care unit.