Is There A Connection Between Primary Hypophysitis and Celiac Disease?

Aim Our aim was to investigate the autoimmune and genetic relationship between primary hypophysitis (PH) and Celiac disease (CD). Methods The study was retrospective and patients with PH followed in our clinic between 2007 and 2022 were evaluated. Clinical, endocrinologic, pathologic, radiologic findings and treatment modalities were assessed. Patients diagnosed with CD in the Gastroenterology outpatient clinic in 2020-2022 were included in the study as a control group. Information such as sociodemographic data, year of diagnosis, HLA DQ2/8 information, Celiac disease-specific antibody levels, pathologic results of duodenal biopsy, treatment received, follow-up status, additional diseases, hormone use, and surgical history was obtained from patient records at PH. In patients diagnosed with primary hypophysitis, a duodenal biopsy was obtained, and the tissue was examined for celiac disease by experienced pathologists. Anti-pituitary and Anti-arginine-vasopressin antibody levels of individuals with PH and CD were measured. Results The study included 19 patients with lymphocytic hypophysitis, 30 celiac patients, and 30 healthy controls. When patients diagnosed with lymphocytic hypophysitis were examined by duodenal biopsy, no evidence of celiac disease was found in the pathologic findings. The detection rate of HLA-DQ2/8 was 80% in celiac patients and 42% in primary hypophysitis (p=0.044). Anti-pituitary and anti-arginine vasopressin (AAVP) antibodies associated with primary hypophysitis were tested in two separate groups of patients and in the control group. Anti-pituitary (AP) and anti-arginine vasopressin (AAVP) levels in PH, CD and healthy controls, respectively M [IQR]: 542 [178-607];164 [125-243]; 82 [74-107] ng/dl (p=0.001), 174 [52-218]; 60 [47-82]; 59 [48-76] ng/dl (p=0.008) were detected. The presence of an HLA-DQ2/8 haplotype correlates with posterior hypophysitis and panhypophysitis (r=0.598, p=0.04 and r=0.657, p=0.02, respectively). Conclusion Although patients with primary hypophysitis were found to have significant levels of HLA-DQ2/8, no celiac disease was found in the tissue. Higher levels of pituitary antibodies were detected in celiac patients compared with healthy controls, but no hypophysitis clinic was observed at follow-up. Although these findings suggest that the two diseases may share a common genetic and autoimmune basis, the development of the disease may be partially explained by exposure to environmental factors.