William C. Shiel Jr., MD, FACP, FACR
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
In this Article
- Diarrhea facts
- What is diarrhea?
- How is diarrhea defined?
- Why does diarrhea develop?
- What symptoms are associated with diarrhea?
- What are common causes of acute diarrhea?
- Viral gastroenteritis
- Food poisoning
- Traveler's diarrhea
- Bacterial enterocolitis
- What are common causes of chronic diarrhea?
- What are the complications of diarrhea?
- When should the doctor be called for diarrhea?
- What tests are useful in the evaluation of diarrhea?
- How can dehydration be prevented and treated?
- What is the treatment for diarrhea?
- When should antibiotics be used for diarrhea?
- Find a local Gastroenterologist in your town
There are many strains of E. coli bacteria. Most of the E. coli bacteria are normal inhabitants of the small intestine and colon and are non-pathogenic, meaning they do not cause disease in the intestines. Nevertheless, these non-pathogenic E. coli can cause diseases if they spread outside of the intestines, for example, into the urinary tract (where they cause bladder or kidney infections) or into the blood stream (sepsis).
Certain strains of E. coli, however, are pathogenic (meaning they can cause disease in the small intestine and colon). These pathogenic strains of E. coli cause diarrhea either by producing toxins (called enterotoxigenic E. coli or ETEC) or by invading and inflaming the lining of the small intestine and the colon and causing enterocolitis (called enteropathogenic E. coli or EPEC). Traveler's diarrhea usually is caused by an ETEC strain of E. coli that produces a diarrhea-inducing toxin.
Tourists visiting foreign countries with warm climates and poor sanitation (Mexico, parts of Africa, etc.) can acquire ETEC by eating contaminated foods such as fruits, vegetables, seafood, raw meat, water, and ice cubes. Toxins produced by ETEC cause the sudden onset of diarrhea, abdominal cramps, nausea, and sometimes vomiting. These symptoms usually occur 3-7 days after arrival in the foreign country and generally subside within 3 days. Occasionally, other bacteria or parasites can cause diarrhea in travelers (for example, Shigella, Giardia, Campylobacter). Diarrhea caused by these other organisms usually lasts longer than 3 days.
Next: Bacterial enterocolitis
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