[Atrophic gastritis presenting with pulmonary embolism]

Atrophic gastritis is an autoimmune gastropathy in which there is destruction of gastric parietal cells. This results in intrinsic factor deficiency and disturbance in vitamin B12 absorption. Its clinical manifestationa are therefore the consequences of B12 deficiency and include anemia and neurological defect. In addition, lack of B12 results in metabolic changes, including disturbances of methionine metabolism and accumulation of homocysteine. In recent years, there has been increasing evidence suggesting that hyperhomocysteinemia is a risk factor for thrombo-embolic disease. We describe a 51-year-old man with atrophic gastritis, severe B12 deficiency and hyperhomocysteinemia. The initial clinical manifestation was pulmonary embolism, without either anemia or neurological signs. B12 deficiency should therefore be considered in patients being investigated for hypercoagulability.