THE XYLOSE EXCRETION TEST IN NORMAL CHILDREN AND IN PEDIATRIC PATIENTS WITH TROPICAL SPRUE

The 5-hour urinary xylose excretion test was performed in 158 normal Puerto Rican school children 2½ to 13 years of age after the administration of a 5 gm oral dose of D-xylose. The values ranged from 0.7 to 2.3 gm with a mean of 1.44 gm and a standard deviation of ± 0.35 gm. Seven children excreted 0.9 gm or less (18% of the oral dose), which was the upper limit of excretion by the patients with untreated tropical sprue. All except one of the values below 1.0 gm occurred in children less than 6½ years of age. Thirty children with proven untreated tropical sprue showed a range of 0.2 to 0.9 gm, with a mean of 0.54 gm and a standard deviation of ± 0.20 gm Seventeen patients with tropical sprue treated for 6 months to 2 years showed a xylose excretion of 1.0 to 2.3 gm with a mean of 1.48 gm and a standard deviation of ± 0.36 gm. The lowest value obtained in this group, 1.0 gm, is higher than the seven lowest values in the control group. Our study confirms that the xylose excretion test is a simple and very reliable test of intestinal absorption. It is very useful as a screening test for the diagnosis of tropical sprue and in the follow up of treated patients.