title: New onset of Crohn's disease during treatment of active ankylosing spondylitis with etanercept.
abstract: We describe 3 AS patients treated with etanercept for active AS who developed new onset of CD while AS related symptoms responded well to etanercept. Typical symptoms of active CD occurred 11, 12, and 26 months after start of etanercept therapy, respectively. On colonoscopy, inflammatory lesions highly compatible with CD were found endoscopically and histologically in all patients. Etanercept was stopped, and CD responded well to standard treatment. One of the 3 patients was reexposed to etanercept later on. While the 2 patients without re-exposure to etanercept did not have further CD flares, the third patient flared 6 months after re-institution of etanercept in combination with azathioprine. New onset of CD may be considered as an immune-mediated injury induced by etanercept. Although this is an intriguing hypothesis, any causative role of etanercept remains unproven at this stage.
authors.affiliation: Department of Rheumatology, Division of Medicine, and Institute for Pathology/Research Center ImmunoSciences (RCIS), Charité Medical University, Campus Benjamin Franklin, Berlin, Germany.
authors.forename: In-Ho
authors.initials: IH
authors.lastname: Song
authors.forename: Heiner
authors.initials: H
authors.lastname: Appel
authors.forename: Hildrun
authors.initials: H
authors.lastname: Haibel
authors.forename: Christoph
authors.initials: C
authors.lastname: Loddenkemper
authors.forename: Jurgen
authors.initials: J
authors.lastname: Braun
authors.forename: Joachin
authors.initials: J
authors.lastname: Sieper
authors.forename: Martin
authors.initials: M
authors.lastname: Rudwaleit
mesh_terms: D000328:Adult; D002986:Clinical Trials as Topic; D003424:Crohn Disease / Q000139:chemically induced / Q000276:immunology* / Q000473:pathology; D000068800:Etanercept; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000009:adverse effects*; D007155:Immunologic Factors / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D018124:Receptors, Tumor Necrosis Factor; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D007074:Immunoglobulin G; D007155:Immunologic Factors; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D000068800:Etanercept