Medical Author: Melissa Conrad Stöppler, MD
E. coli (Escherichia coli) is a type of bacteria that commonly lives in the human intestine of healthy people. However, there are some strains of the bacteria that cause disease. The type of E. coli that normally reside in the intestine can cause disease if they spread outside the intestine (for example, spread into the urinary tract can cause urinary tract infection [UTI]). Other types of E. coli strains (enterovirulent E. coli strains or EEC) cause "poisoning" or diarrhea though they usually remain within the intestine by producing toxins or intestinal inflammation.
E. coli 0157:H7 may cause additional complications in children and the elderly that include renal failure, anemia, and dehydration, especially in children (termed HUS or hemolytic uremic syndrome), as well as spontaneous bleeding, organ failure, and mental changes in the elderly (termed TTP or thrombotic thrombocytopenic purpura).
Early symptoms of E. coli disease include
Diarrhea is present and may be bloody. Later symptoms can be severe and life-threatening if one of the complications described above (HUS or TTP) is present.
Antibiotic treatment has not proven to be useful for E. coli disease; most infections are treated with rest and fluid intake. Serious complications may require blood product transfusions, kidney dialysis, and/or medications to control seizures or blood pressure.
Causes of E. coli infection
The E. coli strain 0157:H7 is the most common type that causes complicated disease in humans, but other types of E. coli produce similar if not identical symptoms. Most of the symptoms caused by the bacteria are due to two Shiga toxins, termed Stx1 and Stx2 and also termed Verotoxins. These toxins are almost identical to toxins produced by the Shigella bacteria that cause dysentery (shigellosis). Infection is usually acquired from consuming contaminated foods.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.
Main Article on E. coli 0157:H7 (Escherichia coli 0157:H7)
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Other Causes of E. coli 0157:H7 (Escherichia coli 0157:H7)
- Abdominal Cramping
- Abdominal Pain
- Blood in Stool
- Bloody Diarrhea
- Decreased Urination
- Easy Bruising
- Generalized Swelling (Edema)
- Loss of Appetite
- Mental Status Changes
- Pale Skin
- Shortness of Breath
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