Diarrhea that lasts for more than 2-4 weeks is considered persistent or chronic. In an otherwise healthy person, chronic diarrhea can be a nuisance at best or become a serious health issue. For someone who has a weakened immune system, chronic diarrhea may represent a life-threatening illness.
Chronic diarrhea has many different causes; these causes can be different for children and adults. Chronic diarrhea sometimes is classified on whether or not it is caused by an infection. The cause of chronic diarrhea sometimes remains unknown.
Chronic Diarrhea caused by an infection may result from:
- Parasites (e.g., Cryptosporidium, Cyclospora, Entamoeba histolytica, Giardia, microsporidia)
- Bacteria (e.g., Aeromonas, Campylobacter, Clostridium difficile, E. coli, Plesiomonas, Salmonella, Shigella)
- Viruses (e.g., norovirus, rotavirus) or
- Unknown causes thought to be infectious (e.g., Brainerd diarrhea)
Chronic Diarrhea not caused by an infection may result from various causes such as:
- Disorders of the pancreas (e.g. chronic pancreatitis, pancreatic enzyme deficiencies, cystic fibrosis)
- Intestinal disorders (e.g. colitis, Crohn’s Disease, irritable bowel syndrome)
- Medications (e.g. antibiotics, laxatives)
- Intolerance to certain foods and food additives (e.g. soy protein, cow’s milk, sorbitol, fructose, olestra)
- Disorders of the thyroid (e.g. hyperthyroidism)
- Previous surgery or radiation of the abdomen or gastrointestinal tract
- Reduced blood flow to the intestine
- Altered immune function (e.g. immunoglobulin deficiencies, AIDS, autoimmune disease)
- Hereditary disorders (e.g. cystic fibrosis, enzyme deficiencies)
Diagnosis of chronic diarrhea can be difficult and requires that your health care provider take a careful health history and perform a physical exam. The types of tests that your health care provider orders will be based on your symptoms and history. Tests may include blood or stool tests. Stool cultures may be used to test for bacteria, parasites or viruses; generally three or more stool samples are collected and examined. Special tests may be required to diagnose some parasites. If these initial tests do not reveal the cause of the diarrhea, additional tests may be done, including radiographs (x-rays) and endoscopy. Endoscopy is a procedure in which a tube is inserted into the mouth or rectum so that the doctor, usually a gastroenterologist, can look at the intestine from the inside.
The risk of serious complications from chronic diarrhea depends on the cause of the diarrhea and the age and general health of the patient. Chronic diarrhea from some causes can result in serious nutritional disorders and malnutrition. Severely immunocompromised persons, including those with HIV/AIDS and those receiving chemotherapy for cancer or organ transplantation can be at risk for serious chronic diarrhea. Determining the correct cause of chronic diarrhea is necessary in order to select proper treatment and reduce the risk of serious complications.
The treatment of chronic diarrhea is determined by its cause. Follow the advice of your health care provider.
- Diarrhea caused by an infection sometimes can be treated with antibiotics or other drugs. However, the correct diagnosis must be made so that the proper medication can be prescribed.
- Diarrhea not caused by an infection can be more difficult to diagnose and therefore treat. Long term medical treatment and nutritional support may be necessary. Surgery may be required to treat some causes of chronic diarrhea.
For diarrhea whose cause has not been determined, the following guidelines may help relieve symptoms. Follow the advice of your health care provider.
- Remain well hydrated and avoid dehydration. Serious health problems can occur if the body does not maintain proper fluid levels. Diarrhea may become worse and hospitalization may be required if dehydration occurs.
- Maintain a well-balanced diet. Doing so may help speed recovery.
- Avoid beverages that contain caffeine, such as tea, coffee, and many soft drinks.
- Avoid alcohol; it can lead to dehydration
Infections that can cause chronic diarrhea usually are spread by ingesting food or water or touching objects contaminated with stool. In general, chronic diarrhea not caused by an infection is not spread to other people.
Infections that cause chronic diarrhea usually can be prevented by
- Always drinking clean safe water that has been properly treated,
- Always using proper food handling and preparation techniques,
- Always maintaining good hand hygiene, including always washing hands properly with soap and water before handling food and after using the toilet or changing a diaper.
This information is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you may have this disease, consult a health care provider.