Deficiency of micronutrients in patients affected by chronic atrophic autoimmune gastritis: A single-institution observational study

Chronic atrophic autoimmune gastritis (CAAG) leads to vitamin B12 deficiency, but other micronutrient deficiencies are largely understudied. To investigate the prevalence of micronutrient deficiencies in CAAG patients and their potential relationship with the grading of gastric atrophy or entero-chromaffin-like cells hyperplasia or body mass index (BMI). From 2005 to 2016 a number of CAAG patients underwent regular follow-up with annual blood testing and upper gastrointestinal tract endoscopy every years. Out of the 122 CAAG patients checked (100 F; median age 65 years), 76 presented nutritional deficiencies, single in 24 and multiple in 52 cases: a deficiency of B12 and iron showed in 42 patients, 25-OH vitamin D lacked in 76 and folic acid in 6 cases. 25-OH vitamin D levels directly correlated with B12 levels and were significantly lower in patients with macronodular than in those with linear or micronodular hyperplasia. No significant correlation was observed between B12, folic acid or ferritin levels and BMI, blood gastrin levels, the grading of gastric atrophy or ECL cells hyperplasia. 25-OH vitamin D deficiency was the main one in CAAG patients: its correlation with B12 deficiency may indicate underlying shared pathogenic mechanisms, although further studies are needed to confirm this hypothesis.