Development of Accurate Test Kits for Malabsorption

Accurate measurement of gastrointestinal absorption of various substances is important in bothresearch and diagnosis. In many cases, the acceptable general approach is the balance procedure. Thisprocedure suffers from the requirement for complete collection of stools over an extended period oftime. This limitation prevents widespread use of this otherwise desirable approach. The investigatorspropose to combine the recent development of Dy as a nonabsorbable fecal marker with the traditionalbalance approach, using both unlabeled continuous feeding and labeled bolus administration, to developpractical procedures for accurate measurement of gastrointestinal absorption of various substances witha simple "grab sample" approach. During Phase I, the investigators will carry out a study with preterminfants focusing on the development of the approach for accurate measurement of fat absorption.During Phase II, the investigators will carry out in-depth research investigating malabsorption of varioussubstances and/or under different conditions for which there is demand to develop "test kits" forroutine use. During Phase III, they will make this new technology available in the form of "test kits" anda central laboratory for complete processing of the kits.