What condition is diagnosed using the D-xylose absorption test?

The D-xylose absorption test is primarily utilized to evaluate the absorption capabilities of the intestines and is particularly effective in diagnosing conditions like pancreatic insufficiency that lead to malabsorption. In cases of pancreatic insufficiency, the pancreas does not produce sufficient enzymes needed for digestion, which can result in inadequate absorption of carbohydrates and other nutrients.

When D-xylose, a simple sugar, is ingested, it should be absorbed efficiently by a healthy intestine and later excreted in the urine. If the D-xylose levels are low in urine, this indicates that the intestines are not absorbing it properly, suggesting a problem with the intestinal mucosa itself rather than just enzyme deficiency, as pancreatic enzymes are not involved in the absorption of D-xylose.

In contrast, conditions related to diabetes mellitus, carbohydrate intolerance, or glycogen synthesis disorders do not primarily focus on intestinal absorption capabilities in the same way, making the D-xylose absorption test unsuitable for diagnosing those particular conditions.