Selenium and glutathione peroxidase status in paediatric health and gastrointestinal disease.

To examine the effect of paediatric GI disease on selenium concentration in plasma and glutathione peroxidase activity in plasma and red cells, results in children with Crohn's disease (n = 39), cystic fibrosis (n = 14), intractable diarrhoea (n = 13), and biliary atresia (n = 10) were compared with those from 86 healthy children undergoing routine operations. In Crohn's disease, plasma selenium concentrations were rarely low, but glutathione peroxidase activity was increased in the plasma and reduced in the red cells. Selenium concentration and glutathione peroxidase activity increased with steroid treatment but decreased with a selenium-deficient elemental diet. Plasma selenium concentration was normal in children with cystic fibrosis but very low in severely malnourished children with biliary atresia and intractable diarrhoea. Selenium concentration and glutathione peroxidase activity should be monitored in children with severe malnutrition or requiring prolonged nutritional support. Supplementation is recommended in cases of severe selenium depletion.