Background: The trace metal zinc has a wide range of important physiologic roles. Indirect evidence suggests that fat malabsorption is associated with malabsorption of zinc. The objective of this study was to evaluate the effect of pancreatic enzyme replacement on zinc absorption in children and adolescents with cystic fibrosis.
Methods: Subjects were four boys and four girls ranging in age from 7 to 17 years of age. All were pancreatic insufficient. Stable isotope labels, 70Zn and 67Zn, were administered orally in divided doses on consecutive days with meals. Meals were identical on the first 2 study days. Subjects were randomized to have pancreatic enzyme replacement withheld on the first or second day. All fecal samples were collected quantitatively for 10 days after label administration and were analyzed individually for total zinc and isotopic enrichment using atomic absorption spectrophotometry and fast atom bombardment mass spectrometry, respectively. Fractional absorption of zinc was calculated from cumulative fecal excretion of unabsorbed label.
Results: Fractional absorption while receiving enzymes was 0.50 +/- 0.29 versus 0.38 +/- 0.24 while not taking enzymes (p = 0.05).
Conclusions: These results indicate that fractional absorption of zinc is impaired by pancreatic insufficiency in patients with cystic fibrosis, and is improved by exocrine pancreatic enzyme replacement.