3 - 10 days
Test Updated:
d-Xylose Absorption Test
Xylose Tolerance Test
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Test Overview
Spectrophotometry
Evaluate mucosal absorption efficiency in a variety of malabsorptive diseases. May be used for diagnosing cause of malabsorption.
Age and dose specific reference ranges provided with report.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
1) Patient should fast for 8 hours (minimum 4 hours) prior to administration of d-xylose. 2) Prior to administration of d-xylose, have patient empty bladder and discard urine. Collect a blood specimen in a red top tube from the fasting patient. 3) Dissolve 25 grams of d-xylose in 250 mL of water and administer, and follow immediately with an additional 250 mL of water. For patients who do not tolerate the 25 g dose, a 5 g dose can be used. For children aged
MLabs does not provide d-xylose; client or physician will need to obtain d-xylose from a local pharmacy. 1) Patient should fast for 8 hours (minimum 4 hours) prior to administration of d-xylose. 2) Prior to administration of d-xylose, have patient empty bladder and discard urine. Collect a blood specimen in a red top tube from the fasting patient. 3) Dissolve 25 grams of d-xylose in 250 mL of water and administer, and follow immediately with an additional 250 mL of water. For patients who do not tolerate the 25 g dose, a 5 g dose can be used. For children aged