Runs A Risk

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Acute diarrhea is defined as lasting less than 14 days and can cause significant illness and even death in rare cases, especially among older patients. In the U.S., there are about 179 million cases of acute diarrhea, or gastroenteritis, per year, including about 48 million cases of food-borne illness. Most adults who have not traveled abroad have no known cause identified for their acute diarrhea, although most non-food related cases are usually viral with norovirus accounting for about 26 percent of cases seen in ERs. Norovirus is often the cause of outbreaks of vomiting and diarrhea on cruise ships, and 90 percent of deaths related to norovirus occur in people 65 and older. Bacterial infections potentially susceptible to antibiotics (Shigella, Salmonella, E coli, etc.) account for less than nine percent of cases seen in ERs.

On the other hand, in traveler’s diarrhea (TD), which is food-borne, antibiotics have been shown to help shorten the duration of symptoms, although the American College of Gastroenterology (ACG) advises against using antibiotics to treat mild cases of TD. TD is commonly seen in people who travel to Mexico and the Caribbean, although it can be seen in travel to most areas outside of the U.S. TD is often caused by bacterial contamination of food or water. Acute diarrhea including TD can be treated with probiotics (if occurring after a course of antibiotics), products containing bismuth subsalicylate (i.e. Pepto Bismol), and loperamide (i.e. Imodium). It is important to remember that taking products that contain bismuth will cause the stool to turn black.

Taking antibiotics for any reason including acute diarrhea has risks and side effects. One of the largest risks occurs when the antibiotics suppress the normal gut bacteria and allow an overgrowth of more resistant, toxic bacteria such as Clostridium difficile (C diff). The antibiotics with the highest risk of C diff are fluoroquinalones (Cipro, Levaquin). C diff infections, most often seen in hospitalized patients on antibiotics, can cause severe bloody diarrhea, dehydration, shock, and death. Therefore the ACG guidelines for treating acute diarrhea take a stepwise approach depending on (1) presence of dysentery (grossly bloody stools); (2) severity of illness (moderate: forced change in activities; severe: total disability); (3) presence of fever of 101 degrees or higher; (4) travel abroad.

Oral hydration is recommended for all forms of diarrhea whether mild or severe. Plus the ACG guidelines are as follows: (1) antibiotics should be avoided for routine acute diarrheal infection as it is usually viral and mild (without fever) TD; (2) probiotics or prebiotics are not recommended for treatment of acute diarrhea in adults, except in cases of post-antibiotic diarrhea; (3) disabling TD with fever should be treated with azithromycin; (4) in patients with TD being treated with antibiotics, loperamide should be added; (5) persistent diarrhea (lasting 14-30 days) should be evaluated with stool culture and (obviously) a visit to the doctor.

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