Polyautoimmunity in autoimmune gastritis.

OBJECTIVES: Autoimmune gastritis may be associated with other organ-specific autoimmune disorders, but the prevalence of this association is not entirely quantified. The aims of this study were to investigate the prevalence of autoimmune disorders and evaluate the factors that might affect this association in patients with autoimmune gastritis.

METHODS: A total of 320 patients with autoimmune gastritis were retrospectively studied and data on concomitant autoimmune diseases, serum gastrin and chromogranin A levels, anti-Hp IgG, antiparietal cell antibodies, presence of enterochromaffin-like cell hyperplasia and gastric atrophy were gathered for each patient and associations between autoimmune gastritis and studied parameters were explored through descriptive statistics and logistic regression analysis.

RESULTS: Of the 320 atrophic body autoimmune gastritis patients, 171 (53.4%) had an associated autoimmune disorder. Autoimmune thyroiditis was the most common concurrent disease, diagnosed in 116 patients (36.2%). Multivariate analysis showed that, presence of enterochromaffin cell hyperplasia (odds ratio [OR] 9.445, 95% confidence [CI]: 4.42-20.22), serum gastrin (OR 3.1, 95% CI: 1.46-6.60) and serum chromogranin A (OR 4.14, 95% CI: 2.01-8.52) levels remained significantly associated with the coexistence of an autoimmune disease.

CONCLUSIONS: Concurrent autoimmune diseases are common in patients with autoimmune gastritis. Autoimmune thyroiditis is the most encountered disease. These data suggest that patients with autoimmune gastritis should be investigated for the presence of an autoimmune disease, in particular patients with enterochromaffin cell hyperplasia and those with serum gastrin and chromogranin A levels above cut-off values.