A 41 year old patient presented with chronic diarrhea for 3 months. A D-xylose absorption test was order to look for:
D-Xylose - monosaccharide, or simple sugar, that does not require enzymes for digestion prior to absorption. Its absorption requires an intact mucosa only. In normal individuals, a 25 g oral dose of D-xylose will be absorbed and excreted in the urine at approximately 4.5 g in 5 hours. A decreased urinary excretion of D-xylose is seen in small intestinal bacterial overgrowth and Whipple's disease. In cases of bacterial overgrowth, the values of D-Xylose absorption return to normal after treatment with antibiotics. In contrast, if the D-xylose urinary excretion is normal, then the problem must be due to a non-mucosal cause of malabsorption (i.e., pancreatic insufficiency).
Carbohydrate malabsorption due to mucosal disease
Carbohydrate malabsorption due to chronic pancreatitis
Fat malabsorption due to mucosal disease
Fat malabsorption due to chronic pancreatitis
Malabsorbtion Syndrome