Acute vs. chronic diarrhea.
Diarrhea can be acute, which is defined as the abrupt onset of three or more loose stools per day; it may also be chronic, lasting longer than 14 days. Chronic diarrhea often has different causes than acute diarrhea, and may be managed differently.
Diagnosing the cause of diarrhea.
When evaluating diarrhea, your physician will want to know the characteristics of your stool, which include the consistency, color, and frequency. It is important to note the presence or absence of other symptoms that include nausea, vomiting, fever or abdominal pain.
Ingestion of raw or contaminated foods may be the cause of your diarrhea, and in children, certain pathogens are routinely transmitted in daycare centers. Other important clues to the etiology of your diarrhea may be exposure to contaminated water or food encountered while traveling or camping. Recent hospitalization, the use of antibiotics, or the presence of conditions that have compromised your immune system are all important parts of your history that will guide you doctor as he determines the cause of your diarrhea.
Dehydration caused by diarrhea.
If you have diarrhea, you may be dehydrated. If it has gone on for a while, your dehydration can be severe enough to cause lethargy, depressed consciousness, dry mucous membranes, and poor perfusion of your tissues with oxygen carrying blood.
Symptoms associated with diarrhea.
Your doctor will look for abdominal tenderness or unusual bowel sounds. In young children or infants, failure to thrive may occur as a result of diarrhea, and the infant may have a sunken fontanel, reduced muscle and fat mass, and poor skin turgor, or elasticity.
Tests for diarrhea.
Some studies your doctor may order include stool samples which will look for parasites or their eggs, a white blood cell count which is important to consider in the diagnosis of an infectious diarrhea, and cultures for Salmonella, Shigella and Campylobacter, which are common pathogens that cause diarrhea. If you are recently hospitalized or have had a recent antibiotic course, your doctor will look for Clostridium difficile, which is a common cause of diarrhea under those conditions. Studies may include special tests for rotavirus or adenovirus antigens.
Treatment of diarrhea.
Acute onset diarrhea usually resolves by itself, but if it is due to an infectious process, it may have a long course. Often, the best therapy is oral rehydration.
Depending upon the cause, your physician may prescribe agents that work against parasites, or antibiotics that work against specific pathogens. Children may be candidates for vaccines that will immunize them against certain common pathogens. Infants require close follow up to ensure that they remain adequately hydrated.