PTU-194 The Diagnostic Utility of Coeliac Serology in Lymphocytic Duodenosis

Abstract

INTRODUCTION: Lymphocytic duodenosis (LD) is defined by normal villous architecture and intraepithelial lymphocytes (IELs) >25 per 100 enterocytes. Such patients should not be diagnosed with coeliac disease (CD), solely by histology, as recent studies have suggested other associations with LD. Coeliac serology (tissue transglutaminase [TTG] and/or endomysial antibodies [EMA]) may play a useful role although their diagnostic value in such settings is unknown. AIMS&METHODS: We aimed to provide diagnostic outcomes in our cohort of LD patients whilst also assessing the clinical utility of coeliac serology. Two hundred patients with LD were rigorously investigated for CD and other known associations of LD, by means of revisiting the patient's history and recent investigations including the initial coeliac serology, followed by a combination of gluten challenge, HLA typing, repeat duodenal biopsies, and exclusion of infection/ inflammatory bowel disease. In the absence of an alternative cause, a diagnosis of CD was based on the persistence or progression of LD on a gluten-containing diet, the presence of HLA DQ2 or DQ8, and a clinical response to a gluten free diet. RESULTS: 150 female, 50 male, mean age 49, SD 16, age range 17-83 An identifiable association was found in 70% of patients: CD (20%), NSAIDs (17%) and H.pylori (16%) accounting for the majority. In 30% no cause was found, although reassuringly 2/3rd normalised their histology. The role of coeliac serology in LD for diagnosing CD is shown in table 1. CONCLUSION: As a single test, EMA has a greater diagnostic accuracy than TTG when assessing patients with LD. As a combination test, only the presence of both a positive EMA and a raised TTG has a 100% predictive value for CD. Therefore, although coeliac serology is useful in LD, most cases still require further work-up for diagnostic confirmation. (Table Presented).