[588] Enterocolic Lymphocytic Phlebitis Is a Common Accompaniment of Diversion Colitis with Coexistent Inflammatory Bowel Disease

S Hafezi, E Montgomery, R Chetty. University Health Network/University of Toronto, Toronto, ON, Canada; Johns Hopkins Medical School, Baltimore, MD

Background: Enterocolic lymphocytic phlebitis (ELP) is a rare entity characterized by circumferential, predominantly lymphocytic infiltration of small submucosal and/or subserosal veins with sparing of arteries. Thought to be a hypersensitivity reaction, its etiopathogenesis and associated lesions are yet to be well elucidated. The aim is to explore the association and incidence of ELP in diversion colitis with and without inflammatory bowel disease.
Design: H&E sections of 150 colon resection specimens (right, left and subtotal) consisting of the following were examined: 26 cases of diversion with ulcerative colitis, 26 cases of ulcerative colitis without diversion colitis, 3 cases of diversion with Crohn's disease, 19 cases of Crohn's disease without diversion colitis, 6 cases of diversion colitis without inflammatory bowel disease and 70 random resection cases with other pathologic findings (carcinoma, adenoma, ischemia, diverticular disease). ELP was defined/diagnosed as submucosal veins showing a concentric, perivascular dense lymphocytic infiltrate with swelling of endothelial cells, cytoplasm of some showing vacuolization. A case was regarded as showing ELP if at least one vein fulfilled the histologic criteria listed above.
Results: ELP was identified in 18/26 cases of diversion colitis with ulcerative colitis, all 3 cases of diversion colitis with Crohn's disease, 2/19 cases of Crohn's disease without diversion colitis and 1 of 26 cases of ulcerative colitis without diversion, 1/6 cases of diversion colitis (a case of diverticular disease) without associated inflammatory bowel disease and in 5/70 cases lacking diversion colitis, ulcerative colitis or Crohn's disease (the so-called random group). One of these 5 cases was for resection of a large tubulo-villous adenoma showing lymphocytic colitis and ELP in a patient on multi-drug therapy.
Conclusions: This series shows that ELP occurs preferentially in colons showing features of diversion colitis with ulcerative colitis or Crohn's disease. It is extremely uncommon in the colons harboring any of these 3 conditions alone. We speculate that a synergistic effect of altered bowel contents from diversion together with the pre-existing immunologic triggers that occur in inflammatory bowel disease, are possible reasons for the occurrence of ELP in this unique set of conditions.
Category: Gastrointestinal

Wednesday, March 11, 2009 9:30 AM

Poster Session V # 69, Wednesday Morning