Non-type A autoimmune gastritis in a patient with IgA deficiency

Selective IgA deficiency is the most common primary immunodeficiency. Gastrointestinal infections, autoimmune diseases and even malignancies have been reported in patients with IgA deficiency. We present a case of a 60-year-old man with selective IgA deficiency, iron deficiency anemia and a normal B12 level that was found to have IgA related gastrointestinal manifestations. Biopsies from the antrum and body demonstrate diffuse antraltype mucosa with chronic inactive gastritis, which is compatible with autoimmune gastritis. There is focal intestinal metaplasia in the antrum but no neuroendocrine hyperplasia. Autoimmune gastritis has been rarely reported in association with selective IgA deficiency. Therefore, the morphologic features along with the clinical history of a male with a normal B12 level suggest the patient has independent autoimmune gastritis associated with IgA deficiency rather than type A autoimmune gastritis. It is important to take the entire clinical picture into account along with the morphologic features identified on biopsy material. If histologic changes are considered in isolation from the clinical picture, the histologic findings can lead to misdiagnosis. Together with the clinical picture, this patient’s histologic features of independent autoimmune gastritis on biopsy can be attributed to manifestations of IgA deficiency, rather than other causes such as type A autoimmune gastritis.