Rectal Nitric Oxide Assessment in Children with Crohn Disease and Ulcerative Colitis. Indicator of Ileocaecal and Colorectal Affection

Abstract

Background: Nitric oxide (NO) production is increased in inflammatory bowel disease (IBD). Measurements of luminal NO in Crohn disease and ulcerative colitis have revealed that levels are increased during active disease. We aim to evaluate whether rectal measurements of NO can reveal active disease of the colon as well as ileum. Methods: Sixteen children with active Crohn disease in the ileocaecal or colorectal regions of the gut and 6 children with active ulcerative colitis were compared to a group of 14 healthy children. Gaseous samples for analysis of luminal NO were collected using a Foley catheter inserted into rectum. The balloon of the catheter was filled with NO-free air and incubated for 10 min. After aspiration, samples were analysed using chemiluminescence. Values are expressed as median and range. Results: In healthy children, rectal NO values were 60 (0-275) ppb. In children with Crohn disease of the colorectal region, NO concentrations were 5,675 (300-49,350) ppb (P < 0.001), while those with Crohn disease of the ileocaecal region had NO levels of 2,625 (300-15,000) ppb (P < 0.01). In children with ulcerative colitis, NO values of 5,500 (950-34,000) ppb were found (P < 0.001). Conclusion: Rectal NO levels are greatly increased in children with IBD. Highest values were found in patients with colorectal engagement, but rectal NO was increased also in ileocaecal disease. Rectal sampling of luminal NO is a simple and minimally invasive method and should be considered a diagnostic tool for intestinal inflammatory activity in children regardless of primary disease location.

• Diagnosis Inflammation Inflammatory Bowel Disease Nitric Oxide