Increased mucosal levels of leukotriene B-4 in pouchitis: Evidence for a persistent inflammatory state

Design and Methods: In order to evaluate its possible role in the pathogenesis of pouchitis we measured the release, into the incubation medium, of leukotriene B-4 from mucosal samples from patients with ileal pouch-anal anastomosis and correlated release with clinical, endoscopic and histological features. Results: Leukotriene B-4 release was significantly elevated in patients with active pouchitis in comparison to those with a normal pouch mucosa (P<0.007). No overlap was observed between leukotriene B-4 levels from patients with active pouchitis samples and those obtained from individuals without pouchitis. Effective treatment of pouchitis was associated with a significant reduction in leukotriene B-4 mucosal release to the incubation medium (P<0.03). However, even in remission, levels of leukotriene B-4 release remained significantly increased in these patients in comparison to people who never experienced pouchitis (P<0.003). A modest correlation was observed between pouchitis disease activity index and leukotriene B-4 release (r=0.596; P<0.01). Conclusion: These results suggest that the increased production of leukotriene B-4 may be implicated in the pathogenesis of pouchitis. The persistence of an increased mucosal release of leukotriene B-4 in pouchitis patients during clinical remission suggests the presence of a chronic, ongoing, underlying inflammatory process.