Quantitative Analysis of Stool Losses in Adult Celiac Disease: Use of Near-Infrared Analysis Reconsidered

Abstract

Background: An attempt has been made to establish whether near-infrared stool analysis is more suitable for quantifying malabsorption than the traditional stool fat analysis. A group of celiac disease (CD) patients was used as index population. Methods. Stool fat, nitrogen, and water were measured with near-infrared analysis of 1- and 3-day stool collections in 96 celiac disease patients on a free diet (in 39 also on gluten-free diet) and in 96 matched controls and 14 patients with latent CD. Results. The fecal output of fat, nitrogen, and water was significantly increased in free-diet CD, whereas their percentage content was only slightly modified compared with controls. None of the variables under consideration differed significantly between the 24-h and 72-h stool specimens. Conclusion. Our data show that the high value of fecal fat, nitrogen, and water, in celiac disease, are mainly due to the fecal weight, whereas the percentage composition of stool does not offer additional diagnostic information. Furthermore, 3-day stool collection is not necessary to confirm or rule out malabsorption in most patients. Near infrared analysis of 24-h specimens is time- and cost-effective and may increase the use of stool analysis and be usefully employed to monitor the clinical follow-up of patients with chronic diarrhea.