Collagenous Ileitis – A Clinicopathological Study of Thirteen (13) Cases.
Blake H O'Brien, Kelly McClymont, Ian S Brown. Royal Brisbane and Women's Hospital, Brisbane, Australia; Sullivan Nicolaides Pathology, Brisbane, Australia
Background: Collagenous ileitis (CI), characterised by sub-epithelial collagen deposition +/- inflammation in the terminal ileum, is an uncommon condition. The few cases reported to date have been associated with collagenous colitis (CC), collagenous gastritis (CG), collagenous sprue (CS) or lymphocytic colitis (LC). There are no previous reports of CI occurring in the absence of collagenous or inflammatory changes elsewhere in the gastro-intestinal tract (GIT).
Design: CI cases were retrieved retrospectively from Sullivan Nicolaides Pathology over a 9 year period from June 2001–2010. Clinical data recorded were symptoms, medications and co-morbidities. Histological parameters recorded were maximum sub-epithelial collagen thickness, percentage of tissue involved by sub-epithelial collagen, intra-epithelial lymphocyte (IEL) density, degree of lamina propria chronic inflammation, eosinophil and neutrophil infiltration and degree of villous atrophy. Findings in colonic, gastric and duodenal biopsies were noted where available.
Results: There were 13 cases (7 females, 6 males) with age range 39-72 (mean 64). Diarrhoea was the presenting symptom in 11 cases. 2 patients (13%) had gluten-sensitive enteropathy (GSE). Collagen thickness was 15-100μm (mean 32μm) and involved 5-80% (mean 35%; <50% in 8 cases) of the sub-epithelial region of the biopsies. 6 cases had >25 IEL/100 epithelial cells. 11 cases showed villous blunting (subtotal n=1, moderate n=4 and mild n=6). Lamina propria chronic inflammation was present in 9 cases (marked n=3; mild or moderate n=6 cases). Eosinophil infiltration was common and >10/HPF in 1 case. Focal neutrophilic infiltrate was observed in 3 cases. 7/13 colonic biopsies showed CC. 4/9 gastric biopsies showed CG. 2/10 duodenal biopsies were abnormal with CS (n=1) and partial villous atrophy and increased IEL (n=1) (both GSE related). In 3 cases, stomach, duodenum and colon were normal. Follow-up was 3-96 months (median 17 months) with 1 case showing collagen disappearance.
Conclusions: Two clinical subgroups of CI exist: 1) CI associated with collagenous or lymphocytic disease elsewhere in the GIT; and 2) CI as an isolated process. We did not identify a cause for the latter group. Diarrhoea is the typical presentation of CI. Histologically, there is overlap between the clinical subgroups. Lamina propria chronic inflammation is often present and generally associated with villous blunting. The collagen deposition is often focal. An increased IEL density is identified in 46%. GSE may be an occasional association.
Wednesday, March 2, 2011 9:30 AM
Poster Session V # 20, Wednesday Morning