D-xylose absorption

The test requires a blood and urine sample. These tests include: Clean catch urine specimen Venipuncture (blood draw) There are several ways to perform this test. A typical procedure is described below, but make sure you follow the specific instructions you are given. You will be asked to drink 8 ounces (240 ml) of…

Do not eat or drink anything (even water) for 8 to 12 hours before the test. Your provider will ask you to rest during the test. A failure to restrict activity may affect test results. Your provider may tell you to stop taking certain medicines that can affect test results. Medicines that can affect test results…

When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing. Urine is collected as part of normal urination with no discomfort.

Your provider may order this test if you have: Persistent diarrhea Signs of malnutrition Unexplained weight loss This test is primarily used to check if nutrient absorption problems are due to a disease of the intestines. It is performed much less often than in the past.

A normal result depends on how much D-xylose is given. In most cases, the test results are either positive or negative. A positive result means that D-xylose is found in the blood or urine and is therefore being absorbed by the intestines. Normal value ranges may vary slightly among different laboratories. Some labs…

Lower than normal values may be seen in: Celiac disease (sprue) Crohn disease Giardia lamblia infestation Hookworm infestation Lymphatic obstruction Radiation enteropathy Small intestinal bacterial overgrowth Viral gastroenteritis Whipple disease

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: Fainting…

Multiple tests may be necessary to determine the reason for malabsorption .

Floch MH. Evaluation of the small bowel. In: Floch MH, ed. Netter's Gastroenterology . 3rd ed. Philadelphia, PA: Elsevier; 2020:chap 62. Semrad CE. Approach to the patient with diarrhea and malabsorption. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine . 27th ed. Philadelphia, PA: Elsevier; 2024:chap 126.…