:Normal range
(5hr urine collection: ≥ 4 g/5 hours (26.6 mmol/5 hours
1hrs after 25 gm xylose serum level: ≥ 25 mg/dL, ≥1.7 mmol/L
1hr (children) after 5 gm xylose serum level: ≥ 20 mg/dL, ≥ 1.3 mmol/L
Comment: d-Xylose is a five- carbon monosaccharide not normally present in significant amounts in the blood. It is passively absorbed unchanged by the normal duodenum and jejunum, and it is excreted unmetaboplized by the kidneys. The d-xylose absorption test is used as screening test for intestinal carbohydrate malabsorption. An oral dose of d-xylose is admistered to the fasting patient, and after a specified period, d-xylose is measured in the patient’s timed urine collection and/or serum specimen. Low recoveries in the urine are consistent with intestinal malabsorption syndromes
Sample: 2hrs after 5 gm xylose serum level, 1hr (children) after 5 gm xylose serum level, 5 hr urine collection