eng Science and Education Publishing International Journal of Celiac Disease 2334-3486 2025-07-14 13 1 1 3 10.12691/ijcd-13-1-1 IJCD20251311 article Fatemeh Elham Mahjoub fmahjoub@tums.ac.ir 1 Mehrnaz Farasat 2 Mehri Najafi Sani 3 Azizollah Yousefi 4 Pegah Pakzadian 5 Fatemeh Farahmand 6 Farzaneh Moatamed 6 Pejman Rohani 7 Shahindoqht Homayoun Valiane 8 Alireza Nourbakhsh 9 Touran Akbari 10 Tehran University of Medical Sciences, Tehran, Iran, Associate Professor in Pathology-Roshan Azma Pathobiology Laboratory, Tehran, Iran Tehran University of Medical Sciences, Tehran, Iran, Internist Tehran University of Medical Sciences, Tehran, Iran. Professor in Pediatric Gastro Enterology Iran University of Medical Sciences, Tehran, Iran, Associate Professor in Pediatric Gastro Enterology Roshan Azma Pathobiology Laboratory, Tehran, Iran, Bachelor of Laboratory Medical Sciences Tehran University of Medical Sciences, Tehran, Iran, Professor in Pediatric Gastro Enterology Tehran University of Medical Sciences, Tehran, Iran, Associate Professor in Pediatric Gastro Enterology Sophia Pathobiology Laboratory. Tehran, Iran Roshan Azma Pathobiology Laboratory, Tehran, Iran, Pathology Laboratory Technician 0Roshan Azma Pathobiology Laboratory, Tehran, Iran, Master of Biochemistry According to the new guidelines of the European Society for Pediatric Gastroenterology Hepatology and Nutrition [1], it is mandatory to test for anti tissue transglutaminase IgA (anti TTG IgA) and serum IgA in first step in the diagnosis of celiac disease. A diagnosis of celiac disease can be made when the anti-TTG IgA titer is ten times normal (with normal Ig A level) and anti-endomysial antibody (EMA) is positive in the second blood sample, without requiring biopsy. In this article, we present cases of anti TTG IgA levels more than ten times the upper limit of normal determined by ELISA (enzyme-linked immunosorbent assay). In some patients, EMA was checked and in all of these cases upper endoscopy and duodenal biopsy was performed for confirmation, Although biopsy was performed from the bulb and the second part of the duodenum, and the number of biopsies were adequate; no evidence of celiac disease was observed on histological examination. These patients were recruited, and another blood sample was taken and anti TTG IgA was checked by a chemiluminescence immunoassay (CLIA) and the levels were reported normal. https://pubs.sciepub.com/ijcd/13/1/1/ijcd-13-1-1.pdf Celiac Disease Serology Anti Tissue Transglutaminase Enzyme Linked Immunosorbent Assay (ELISA) Chemiluminescent Immunoassay (CLIA)