To determine the cause of chronic diarrhea in children, the health care provider will take a complete medical and family history and conduct a physical exam, and may perform tests.
                
Medical and family history. Taking a medical and family history is one of the first things a health care provider may do to help determine the cause of chronic diarrhea. He or she will ask for information about symptoms, such as
                
- how long the child has had diarrhea  - the amount of stool passed  - the frequency of diarrhea  - the appearance of the stool  - the presence of other symptoms that accompany diarrhea
                
The health care provider will ask about the childs diet and may recommend keeping a diary of the childs diet and bowel habits. If the health care provider suspects a food allergy or intolerance, he or she may recommend changing the childs diet to see if symptoms improve.
                
The health care provider may also ask about family medical history. Some of the conditions that cause chronic diarrhea, such as celiac disease and lactose intolerance, run in families.
                
Physical exam. After taking a medical history, a health care provider will perform a physical exam, which may help determine the cause of chronic diarrhea. During a physical exam, a health care provider usually
                
- examines a childs body  - uses a stethoscope to listen to bodily sounds  - taps on specific areas of the childs body
                
Tests. The health care provider may perform one or more of the following tests:
                
- Stool test. A stool test is the analysis of a sample of stool. The health care provider will give the parent or caretaker a container for catching and storing the stool. The parent or caretaker returns the sample to the health care provider or a commercial facility that will send the sample to a lab for analysis. Stool tests can show the presence of blood, bacteria, or parasites or signs of diseases and disorders. The health care provider may also do a rectal exam, sometimes during the physical exam. For a rectal exam, the health care provider inserts a gloved, lubricated finger into the rectum to check for blood in the stool.    - Blood test. A blood test involves drawing blood at a health care providers office or a commercial facility and sending the sample to a lab for analysis. The blood test can show signs of certain diseases and disorders that can cause chronic diarrhea in children, including      - high levels of white blood cells, which may be a sign of inflammation or infection somewhere in the body    - anemia, which may be a sign of bleeding in the GI tract or of malabsorption    - the presence of certain antibodiesproteins that react against the bodys own cells or tissueswhich may be a sign of celiac disease      - Hydrogen breath test. This test measures the amount of hydrogen in a childs breath. Normally, only a small amount of hydrogen is detectable in the breath. However, bacteria break down sugarssuch as lactose and fructosethat are not digested by the small intestine and produce high levels of hydrogen. In small intestinal bacterial overgrowth, bacteria break down sugars in the small intestine and produce hydrogen.  For this test, the child breathes into a balloonlike container that measures hydrogen. Then, the child drinks a lactose-loaded beverage, and the childs breath is analyzed at regular intervals to measure the amount of hydrogen. In most cases, a health care provider performs this test at a hospital, on an outpatient basis. A health care provider may use a hydrogen breath test to check for signs of lactose intolerance, fructose intolerance, or small intestinal bacterial overgrowth.    - Upper GI endoscopy. This procedure involves using an endoscopea small, flexible tube with a lightto see the upper GI tract, which includes the esophagus, stomach, and duodenum, the first part of the small intestine. A gastroenterologista doctor who specializes in digestive diseasesperforms the test at a hospital or an outpatient center. The endoscope is carefully fed down the esophagus and into the stomach and duodenum. A small camera mounted on the endoscope transmits a video image to a monitor, allowing close examination of the intestinal lining. A child may receive a liquid anesthetic that is gargled or sprayed on the back of the throat. A health care provider will place an intravenous (IV) needle in a vein in the arm if general anesthesia is given.  The health care provider may use instruments passed through the endoscope to perform a biopsy or collect fluid. A biopsy is a procedure that involves taking a piece of tissue for examination with a microscope. A pathologista doctor who specializes in diagnosing diseasesexamines the tissues in a lab. This test can show problems in the upper GI tract that may cause chronic diarrhea. For example, a biopsy of the small intestine can show signs of celiac disease. A health care provider may use a fluid sample from the small intestine to check for bacteria to diagnose small intestinal bacterial overgrowth.    - Flexible sigmoidoscopy or colonoscopy. While these tests are similar, a health care provider uses a colonoscopy to view the rectum and entire colon and a flexible sigmoidoscopy to view just the rectum and lower colon. A gastroenterologist performs these tests at a hospital or an outpatient center. For both tests, the health care provider will give written bowel prep instructions for the child to follow at home. The health care provider may ask that the child follow a clear liquid diet the day before either test. The child may require a laxative for 4 days before either test or only the day before either test. The child may require an enema the day before either test. These medications cause diarrhea, so the child should stay close to a bathroom during the bowel prep.  In most cases, light anesthesia, and possibly pain medication, helps the child relax. For either test, the child will lie on a table while the gastroenterologist inserts a flexible tube into the anus. A small camera on the tube sends a video image of the intestinal lining to a computer screen. The gastroenterologist may also perform a biopsy by taking a small piece of tissue from the intestinal lining. The child will not feel the biopsy. These tests can show problems in the rectum or colon, such as signs of IBD.  Cramping or bloating may occur during the first hour after these tests. The child should recover fully by the next day and be able to return to a normal diet.