Background: Inflammation is known to be associated with enhanced nitric oxide production. A role for nitric oxide in coeliac disease has been suggested because of increased expression of the inducible isoform of nitric oxide synthase in the small intestine of patients with untreated coeliac disease.
Design: During small bowel endoscopy in 11 control subjects, 10 patients with untreated coeliac disease and seven patients with treated coeliac disease, gas was aspirated from different parts of the upper gastrointestinal tract and immediately analysed using a chemiluminescence technique. Luminal nitric oxide concentrations were also quantified in 13 control subjects who had undergone colonoscopy.
Results: Jejunal luminal nitric oxide concentrations were more than 20 times higher in patients with coeliac disease than in normal control subjects (mean 755 +/- 173 ppb, range 215-1690 ppb, vs. mean 31 +/- 9 ppb, range 1-83 ppb, P < 0.001). Jejunal luminal nitric oxide levels in patients with treated coeliac disease (mean 54 +/- 18 ppb, range 3-126 ppb) did not differ from those of control subjects.
Conclusions: This study shows that intraluminal jejunal nitric oxide concentrations are significantly increased in patients with untreated active coeliac disease.