What are other Names for this Test? (Equivalent Terms)
- D-Xylose Absorption Test
What is D-Xylose Absorption Blood and Urine Test? (Background Information)
- D-xylose is a simple sugar that does not require digestion prior to absorption. It is used to assess the body’s ability to absorb nutrients from food
- After D-xylose has been administered, levels in the blood and urine should increase as the sugar is absorbed by the small intestine and excreted through the urine. This would indicate a normal, healthy absorptive ability
- However, various disorders of the small intestine interfere with its ability to absorb nutrients from food. These include celiac disease and disorders of unbalanced microbial population levels
- The D-Xylose Absorption Blood and Urine Test helps determine the levels of D-xylose in blood and urine, after a known amount (25 grams) has been ingested. It is used to aid in the diagnosis of malabsorptive disorders
What are the Clinical Indications for performing the D-Xylose Absorption Blood and Urine Test?
Following are the clinical indications for performing the D-Xylose Blood and Urine Test:
- Rapid weight loss
- Abdominal pain
How is the Specimen Collected for D-Xylose Absorption Blood and Urine Test?
Following is the specimen collection process for D-Xylose Blood and Urine Test:
Sample required: Blood and urine
Process of obtaining blood sample in adults:
- A band is wrapped around the arm, 3-4 inches above the collection site (superficial vein that lies within the elbow pit)
- The site is cleaned with 70% alcohol in an outward spiral, away from the zone of needle insertion
- The needle cap is removed and is held in line with the vein, pulling the skin tight
- With a small and quick thrust, the vein is penetrated using the needle
- The required amount of blood sample is collected by pulling the plunger of the syringe out slowly
- The wrap band is removed, gauze is placed on the collection site, and the needle is removed
- The blood is immediately transferred into the blood container, which has the appropriate preservative/clot activator/anti-coagulant
- The syringe and the needle are disposed into the appropriate “sharp container” for safe and hygienic disposal
Process of obtaining a urine sample in adults: Urination into a sterile container over a 24-hour period.
- No special preparation is needed prior to the blood test
- Drinking 6-8 glasses of water or other fluids is advised prior to the urine test
What is the Significance of the D-Xylose Absorption Blood and Urine Test Result?
A low value for the D-Xylose Absorption Blood and Urine Test may indicate:
- Celiac disease
- Whipple’s disease
- Radiation enteritis
- Diabetic neuropathy
- Massive intestinal resection
- Small-bowel ischemia
- Zollinger-Ellison syndrome
- Multiple jejunal diverticula
- Bacterial overgrowth
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- Certain factors may interfere with the results of the D-Xylose Absorption Blood and Urine Test. These include diet, hydration status, alcohol consumption, and vomiting
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.
The following DoveMed website links are useful resources for additional information:
Please visit our Laboratory Procedures Center for more physician-approved health information: