Vitamin B₁₂ Malabsorption Due to Intrinsic Factor Deficiency in Indian Subjects

Sixteen patients (from Bombay) with severe vitamin B₁₂ malabsorption due to intrinsic factor deficiency, presenting as subacute combined degeneration of the cord (7), tropical sprue (3), anemia (2), thyrotoxicosis (2), diabetes mellitus (1), and pain in the abdomen (1), are reported. The difficulties of establishing a definite diagnosis of pernicious anemia in Indian population are described. The lower incidence of circulating intrinsic factor antibody (IFA) in Indian patients with histamine-fast achlorhydria and poor vitamin B₁₂ absorption is emphasized. The necessity of separating atrophic gastritis, with severely impaired vitamm B₁₂ absorption, from pernicious anemia on the basis of absence or presence of IFA in serum and/or gastric juice cannot be overemphasized.