Necrotizing+Fasciitis

By Nicole Umemoto-Snyder 5/20/2010
 * Necrotizing Fasciitis: "Flesh Eating" Disease**

__**Abstract**__: While deemed the 'flesh eating disease' toxins actually cause necrosis (death) and gangrene of the skin, it interferes with blood flow to the tissue, and break down important components of the tissue which can spread the bacteria more quickly possibly causing systemic shock. Necrotizing fasciitis is a microbial skin disease most commonly caused by Group A streptococcus (GAS), a gram positive anaerobic cocci. It is considered a rare disease as affects less than 200,000 people in the US. It's a severe soft tissue infection with rapidly progressive necrosis of subcutaneous tissue and superficial fascia. Necrotizing fasciitis is a potentially fatal disease with a 25% mortality rate even with all of the advances made in medicine. It can also be caused by Staphylococcus aureus, Vibrio vulnificus, Clostridium perfringens, and Bacteroides fragilis. __**Introduction**__: I chose to do my research project on Necrotizing fasciitis because I thought it was interesting how streptococcus can cause such a wide variety of diseases. It can cause Necrotizing fasciitis to strep throat to being completely benign. It reinforced to me the importance of thouroughly cleaning cuts and scrapes. People can carry the virus without symptoms or any complications until the skin is broken it can then enter the body and cause necrosis and gangrene of the skin. It makes me think of all the times I had a cut or scrape and ignored it and to think it could have possibly, although not likely, turned into this disease had I had a bacteria that causes it on my skin. Even though this disease is rare I know I'd like to avoid being one of the 200,000 affected by it in the United States.

__**Discussion**:__ Streptococcal M-protein types secrete exotoxin A an important factor in the development of Necrotizing fasciitis, "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 that are normally intended to destroy bacteria but are capable of damaging nearly any macromolecule they contact in the body."(1) It was originally associated with beta hemolytic streptococcus it is now known that a variety of bacteria can cause it. The mean age of a patient infected with necrotizing fasciitis is between 38-44 years old. "A highly virulent strain of S. pyogenes has been associated with severe necrotizing fasciitis". (5) Pediatric cases are rare but more common in third world countries where hygiene is poor. "When it occurs on the genitals, it is called Fournier gangrene."(4) "Destruction of the tissue hs been reported to occur at a rate of 2 inches per hour. Incubation period for most streptocococcal infections rarely exceeds 3 days, reinfections are common because immune responses to streptococcal infections is minimal."(5) __**Causes**:__ Your chances of acquiring necrotizing fasciitis are increased if an open wound comes into contact with ocean water, raw oysters, or acquire an injury from handling sea animals, especially in immuno-compromised people. "It can be transmitted from an infected person through close contact, kissing, or touching infected person's wounds. The risk is even higher if the uninfected person has an open wound, chicken pox, or impaired immune system."(6) The elderly, and adults with a history of alcohol abuse or injection drug use also have a higher risk for disease."(3) __**Symptoms**__: Symptoms of Necrotizing fasciitis can start as soon as 24 hours after a an injury (even a minor scrape or cut) the symptoms can include; nausea and vomiting, diarrhea, pain, swelling, red streaks leading from the wound, pus draining from the wound, swollen and painful lymph nodes, serosanguineous blisters, and edema. The pain of a wound infected with Necrotizing fasciitis is much more severe than an average wound and it is normally accompanied by flu like symptoms. __**Treatment**:__ Early diagnosis is critical, if treatment is postponed too long it often results in death or limb amputation. Wide local surgical debridement (removal of all infected tissue and liquids) and antibiotic such as clindamyacin and penicillin are used to kill certain bacteria that cause necrotizing fasciitis. IV immunoglobin kills infection and boosts immune system, along with treatments of the accompanying complications such as shock and organ failure. Hyperbaric oxygen therapy is used to prevent tissue death and encourage healing. This usually only works if necrotizing fasciitis is causd by an anaerobe. "Penicilin is usually the first chice for infections caused by group A streptococci however, some B strains are resisant but are susceptible to Ampiciln" (5) Several methods are usually needed to gain full control of the infection. Unfortunately necrotizing fasciitis occurs beneath the skin and leaves few visible symptoms and often leads to misdiagnosis."After surgical debridement skin grafts are generally required." (6) __**es**:__??

Literature Cited (must be in alphabetical order):

1. Zorkun M.D, Ph.D., Cafer. "Necrotizing fasciitis". 4/10/10 http://www.wikidoc.org/index.php/Necrotizing_fasciitis.

2.W.N. Tang, P.L. Ho, W.P. Yau, J.W.K. Wong, and D.K.H Yip. "Report of 2 Fatal Cases of Adult Necrotizing Fasciitis and Toxic Shock Syndrome Caused by Streptococcus agalactiae". Department of Orthopaedic Surgery and Department of Microbiology University of Hong Kong, China. 4/10/10 [].

3. CDC Department of Health and Human Services, "Group A Streptococcal (GAS) Disease: Strep throat, necrotizing fasciitis, impetigo". National Center for Immunization and Respiratory Diseases: Division of Bacterial Diseases. 4/10/10 .

4. WebMD, "Necrotizing Fasciitis (Fleshe-Eating Bacteria)". Healthwise Inc.. 4/11/10 [].

5. Bergquist, Lois M., and Barbara Pogosian. __Microbiology Principles and Health Science Applications__. New York: W.B. Saunders Company, 2000.

6.Tortora, Gerard J., Berdell R. Funke, and Christine L. Case. //Microbiology: an Introduction//. San Francisco, CA: Pearson Benjamin Cummings, 2010. Print.