Efficacy of infliximab for extraintestinal manifestations of inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC), collectively referred to as inflammatory bowel disease (IBD), are associated with extraintestinal manifestations (EIMs) in approximately 40% of patients. Infliximab, a chimeric monoclonal antibody to tumor necrosis factor-alpha, is effective for induction and maintenance of remission of CD and UC. The role of infliximab for EIMs related to IBD has been less studied, but it is likely as effective. The EIMs may run a course that parallels IBD activity or may present separately. The EIMs that parallel intestinal inflammation (eg, peripheral arthritis, pyoderma gangrenosum, erythema nodosum, and episcleritis) generally respond to infliximab. Therefore, treating patients with IBD who have one of these EIMs will more often than not improve the EIM. The EIMs that run a separate course from IBD are more difficult to treat. Ankylosing spondylitis (AS), uveitis, and primary sclerosing cholangitis (PSC) have variable responses to IBD medications. Infliximab is efficacious for uveitis and is approved by the US Food and Drug Administration for treatment of AS. The efficacy of infliximab for PSC is unknown. The dosing schedule of infliximab for IBD patients with EIMs should be induction doses with 5 mg/kg at 0, 2, and 6 weeks followed by every 8 weeks. Whether long-term infliximab therapy is necessary to maintain remission of EIMs, as in the case of IBD, has not been established.