EFFECTS OF PANCREATIC-ENZYME PREPARATIONS ON ERYTHROCYTE GLUTATHIONE-PEROXIDASE ACTIVITIES AND PLASMA SELENIUM CONCENTRATIONS IN CYSTIC-FIBROSIS

To substitute for exocrine pancreatic insufficiency, patients with cys tic fibrosis (CF) take pancreatic enzymes (PE) originating from porcin e pancreas. Five different pancreatic enzyme preparations used by our patients contained 0.5-1.4 mu g selenium per g tablet. In patients tak ing PE in doses that were,gradually increased to improve fat absorptio n during a 48-month period, the effects of PE dose on erythrocyte sele nium-dependent glutathione peroxidase (SeGSH-Px) activities and plasma selenium concentrations were studied. At baseline, erythrocyte SeGSH- Px activities were significantly lower in patients (p =.01), while pla sma selenium concentrations did not differ between patients and health y subjects. When PE dose and, consequently, selenium intake from PE wa s increased, erythrocyte SeGSH-Px activities (p <.001) and plasma sele nium concentrations (p =.02) increased. Changes in SeGSH-Px activities during the initial 8 months correlated with those in selenium intake from PE (r = 0.67, p <.001), Plasma selenium concentrations plateaued at 12 months and erythrocyte SeGSH-Px activities did so at 36 months, when patients had reached SeGSH-Px activities similar to those of heal thy subjects. At 48 months, patients took an average lipase dose of 17 400 U kg(-1) d(-1) and selenium dose from PE of 0.53 mu g kg(-1) d(-1) . We conclude that selenium content of PE preparations has a significa nt effect on SeGSH-Px activity in patients with CF. This form of selen ium supply needs to be taken into account when selenium supplements ar e given to patients with CF. (C) 1998 Elsevier Science Inc.