Histopathology of non-coeliac gluten sensitivity.

Diagnosis of non-coeliac gluten sensitivity (NCGS) remains still problematic due to the subjectiveness and lack of a specific biomarker. We aimed to compare NCGS duodenal mucosae with healthy individuals and Marsh type 1 coeliac disease (CD), to determine whether NCGS has characteristic histological features. A total of 44 healthy controls, 42 NCGS, and 44 type 1 CD patients were selected according to clinical, serological, and laboratory data. Duodenal biopsies were evaluated on H&E, CD, and CD117 for villus/crypt ratio, IEL counts/100 enterocytes, uneven distribution pattern with clusters of IELs in the villous epithelium, linear distribution of T lymphocytes in the basal lamina propria, and eosinophils and mast cells in the lamina propria. IEL counts were within normal range in controls (13 ± 7.65), normal or mildly increased in NCGS (24.7 ± 10.46), and increased in CD (58.79 ± 14.97) on CD3. The presence of uneven distribution pattern of IELs in the villous epithelium was significantly higher in NCGS (90.5%), in contrast to controls (27.3%) and CD (34.1%). The presence of linear distribution of T lymphocytes in the basal lamina propria (68.2%, 76.2%, 78.1%), eosinophil counts (6.85 ± 3.42, 6.21 ± 2.8, 7.62 ± 3.89), and mast cell counts (25.1 ± 5.1, 26 ± 2.9, 30.3 ± 4.4) was similar in controls, NCGS, and CD, respectively. In conclusion, duodenal mucosae in NCGS are characterized by preserved villous architecture, normal or mildly increased IELs with clusters, and eosinophils and mast cells within normal limits. We believe uneven distribution of IELs with clusters in the villous epithelium can be used as a supportive histopathological tool for NCGS in the right clinical setting.