digestive disorders
Overview of Malabsorption
Diagnosis of Malabsorption
A doctor's evaluation of the person's history and symptoms Tests to confirm the diagnosis (such as blood and stool tests) Tests to diagnose the cause (such as biopsy and imaging) A doctor suspects malabsorption when a person has chronic diarrhea, weight loss, anemia, and other signs of nutritional deficiencies. Malabsorption is less obvious and often more difficult to recognize in older people than in children. Laboratory tests can help confirm the diagnosis: Tests to measure fat in stool Visual examination of stool Blood tests Astool testthat directly measures the amount of fat in stool that has been collected over 3 days is the most reliable one for diagnosing malabsorption of fat, which is present in almost all malabsorption disorders. A finding of more than 7 grams of fat in the stool daily is the hallmark of malabsorption. Also available are a few other tests that measure fat in the stool but do not require the 3-day collection of stool. Stool samples are examined with the unaided eye as well as under the microscope. Undigested food fragments may mean that food passes through the intestine too rapidly. In a person with jaundice, stool with excess fat indicates decreased production or secretion of bile. Sometimes parasites or their eggs are seen under the microscope, suggesting that malabsorption is caused by a parasitic infection. Blood testsand other laboratory tests can be done to detect malabsorption of other specific substances, such as lactose or vitamin B12. Once a doctor confirms a person has a malabsorption disorder, tests are done to diagnose the cause: Biopsy Imaging tests Pancreatic function tests Abiopsymay be needed to detect abnormalities in the lining of the small intestine. The tissue is removed through an endoscope (a flexible viewing tube equipped with a light source and a camera through which a small clipper can be inserted) passed through the mouth and into the small intestine. such as Video Capsule Endoscopy , Pancreatic function testsare done if the doctor thinks that the cause of malabsorption may be the insufficient production of digestive enzymes by the pancreas. However, some of these tests are complex, time-consuming, and invasive. In one test, a tube is passed through the mouth and guided into the small intestine, where intestinal fluids containing pancreatic secretions can be collected and measured. In another test, the person swallows a substance that requires pancreatic enzymes for its digestion. The products of digestion are then measured in the urine. Recently, doctors have been doing simpler and easier tests that measure levels of certain pancreatic enzymes in the stool. Other diagnostic tests (including culture of digestive bacteria, certain blood tests, or breath tests) may also be done. 