Circulating antioxidant concentrations in children with inflammatory bowel disease.

The mechanisms by which inflammatory bowel disease causes chronic injury to the gastrointestinal tract are poorly understood. To determine whether antioxidant defenses might be altered, we evaluated plasma antioxidant concentrations in 24 children with inflammatory bowel disease (12 with Crohn disease and 12 with ulcerative colitis) and in 23 healthy control subjects. Anthropometric measurements and disease activity scores were obtained. The groups were of similar age and sex distribution; most children had quiescent or mild disease. The children with Crohn disease were malnourished compared with the ulcerative colitis and control groups. Children with inflammatory bowel disease had decreased plasma ascorbic acid and increased glutathione peroxidase, glutathione, and alpha-tocopherol (vitamin E) concentrations compared with control subjects. These differences were found primarily in the children with Crohn disease. This study provides evidence that children with Crohn disease have alterations in circulating antioxidant defenses, possibly related to an ongoing oxidant stress.