Positions of selective leukocytapheresis in the medical therapy of ulcerative colitis.
Ulcerative colitis (UC) and Crohn's disease (CD) are the major forms of idiopathic inflammatory bowel disease (IBD). Both UC and CD are debilitating chronic disorders that afflict millions of individuals throughout the world with symptoms which impair function and quality of life. The etiology of IBD is inadequately understood and therefore, drug therapy has been empirical instead of being based on sound understanding of IBD pathogenesis. This is a major factor for poor drug efficacy and drug related side effects that often add to the disease complexity. The development of biologicals notably infliximab to intercept tumor necrosis factor (TNF)-alpha reflects some progress, albeit major concern about their side effects and lack of long-term safety and efficacy profiles. However, IBD seems to be perpetuated by inflammatory cytokines like TNF-alpha, interleukin (IL)-1beta, IL-6 and IL-8 for which activated peripheral granulocytes and monocytes/macrophages (GM) are major sources. Further, in IBD, peripheral GMs are elevated with activation behavior, increased survival time and are found in vast numbers within the inflamed intestinal mucosa; they are suspected to be major factors in the immunopathogenesis of IBD. Hence, peripheral blood GMs should be appropriate targets of therapy. The Adacolumn is a medical device developed for selective depletion of GM by receptor-mediated adsorption (GMA). Clinical data show GMA, in patients with steroid dependent or steroid refractory UC, is associated with up to 85% efficacy and tapering or discontinuation of steroids, while in steroid naive patients (the best responders), GMA spares patients from exposure to steroids. Likewise, GMA at appropriate intervals in patients at a high risk of clinical relapse suppresses relapse thus sparing the patients from the morbidity associated with IBD relapse. Further, GMA appears to reduce the number of patients being submitted to colectomy or exposure to unsafe immunosupressants. First UC episode, steroid naivety and short disease duration appear good predictors of response to GMA and based on the available data, GMA seems to have an excellent safety profile.
Hanai
Hiroyuki
H
Center for Gastroenterology and Inflammatory Bowel Disease Research, Hamamatsu South Hospital, 26 Shirowacho, Hamamatsu 4300846, Japan.
D003093:Colitis, Ulcerative / Q000276:immunology* / Q000628:therapy*; D006801:Humans; D007937:Leukapheresis