Ultra-short Celiac Disease Exhibits Differential Genetic and Immunophenotypic Features Compared to Conventional Celiac Disease.

Background: Ultra-short coeliac disease (USCD) is a novel celiac disease (CD) subtype limited to the duodenal bulb (D1). HLA haptotypes and flow cytometry have not been assessed yet. Aims: To compare genetic, clinical, serologic, histopathotogic and inmmunophenotypic parameters between USCD and conventional celiac disease (CCD) patients. Methods: Prospective single-center study in children and adult patients undergoing duodenal biopsies on a gluten-containing diet. Biopsies for histology and flow cytometry were taken separately from D1 and distal duodenum. Biopsies in seronegative patients with celiac lymphogrann were repeated after 2 years on a gluten-free diet. Results: Among 505 included patients, 127 were diagnosed with CD, of whom 7 (5.5%) showed USCD. HLADQ2 was significantly less common in USCD compared to CCD (71% vs. 95%, p 0.003). Likewise, USCD patients showed more frequent non-significant seronegativity (28% vs. 8%, p 0.07) and significantly lower titrations (7-15 IU/ml) of tissue transglutaminase antibodies (tTGIgA) (60% vs. 13%, p< 0.001). Biopsies from D1 revealed significant less NK cells down-expression in USCD patients (1.4 vs. 5, p 0.04). Conclusions: Up to 5.5% of CD patients showed USCD. A lower frequency of HLADQ2, along with less serum tTG-IgA titration and duodenal NK cell suppression, were differential features of USCD. (C) 2022 Elsevier Espana, S.L.U. All rights reserved.