Zinc homeostasis and gut function in children with celiac disease

Background: Celiac disease (CD) is an immunologic enteropathy triggered by the intake of gluten. It is thought that the enteropathy impairs gut function and absorption. Objective: We assessed the zinc-absorption capacity and small-bowel integrity in children with CD. Design: Children in whom a diagnosis of CD was considered clinically and either confirmed (n = 16; Marsh score >= 3) or not (n = 22; Marsh score of 0) with a small-bowel biopsy (SBB) were recruited. The fractional absorption of zinc (FAZ) was determined by the administration of an oral Zn-67 dose (2.5 mg) and an intravenous Zn-70 dose (0.2 mg) 2 h before and during the SBB, respectively. Spot urine samples were collected, and zinc isotopic ratios were determined by ion-coupled plasma mass spectrometry. Gut health was assessed by the ingestion of C-13-sucrose (20 g) after an overnight fast, and breath samples were collected and analyzed by isotope ratio mass spectrometry. Results: There was no difference in FAZ between children with a Marsh score >= 3 (mean +/- SEM: 0.68 +/- 0.05) and children with a Marsh score of 0 (0.74 +/- 0.05). The exchangeable zinc pool (EZP) was significantly (P < 0.05) lower in children with a Marsh score >= 3 (2.6 +/- 0.8 mg/kg) than in children with a Marsh score of 0 (3.8 +/- 1.4 mg/kg). Gut function in children with a Marsh score >= 3 (4.5 +/- 0.7% cumulative dose recovered at 90 min) was lower than the lower cutoff of a normal gut-function breath test (5.06% cumulative dose recovered at 90 min) but not significantly different from that in children with a Marsh score of 0 (4.9 +/- 0.4%). There was a significant (P < 0.01) correlation between zinc absorption and gut function in children with CD. Conclusions: Zinc absorption did not appear below usual amounts in subjects with CD. Children with CD have impaired gut function that may affect their zinc nutritional status as shown by a smaller EZP. However, the EZP decrease in children with CD was not compared with that in healthy control subjects, and its biological meaning is uncertain. Am J Clin Nutr 2011;94:1026-32.