Value of chromo-magnification endoscopy and targeted biopsies in the diagnosis of celiac disease with previously negative histology: a preliminary study

T1608 Value of Chromo-Magnification Endoscopy and Targeted Biopsies in the Diagnosis of Celiac Disease with Previously Negative Histology: A Preliminary Study Annalisa Pascariello, Carolina Ciacci, Ilaria Russo, Luca Magno, Giuseppe Galloro, Paola Iovino Introduction. Chromoendoscopy with magnification has been previously demonstrated to be valuable in assessing the degree of intestinal villous atrophy in patients with suspected celiac disease. Aim and Methods. The aim of this study is to determine the accuracy of these methods in association with targeted biopsies in the diagnosis of suspected celiac disease in cases of positive serology and previous negative histology.13 patients (12 females, range 17-43 years) with a positive/border-line value of anti-tissue transglutaminase antibodies and a previous negative histopathologic evaluation underwent upper endoscopy for the purpose of obtaining duodenal targeted biopsy specimens. In all patients we performed chromoendoscopy with indigo carmine sprayed onto the duodenal mucosa and, thereafter, a full magnification of duodenal mucosa. A villous pattern score was allocated for each patients at the end of procedure as definitely present = 1, partially present =2, definitely absent = 3. Biopsies were taken from the most abnormal-looking mucosa or apparent normal when present using rocking biopsy forceps and mounted on filter paper and put into formalin for histological assessment. Three more samples were collected for In Vitro challenge with gluten-derived toxic peptides . Frozen sections of the biopsies were then evaluated by immunohistochemistry. Results. 76.9%of subject had a positive value of anti-tissue transglutaminase antibodies while 23.1 % had borderline value. The chromoendoscopic results showed normal villous pattern in 46.2%(6 pts), partially present 15.4%(2 pts ), definitively absent 38.5% (5pts). A significant positive correlation was found between a positive value of anti-tissue transglutaminase antibodies and the endoscopic score of villous pattern (Spearman, r = 0,56, p < 0.05). In Vitro challenge was positive in 50% of normal villous pattern and in all patients with definitively absent villous pattern. Conclusions. This preliminary study suggest that chromoendoscopy with magnification may disclose with accuracy severe villous atrophy but it may have a great value in evaluating selected series of patients with doubtful diagnosis of celiac disease.