An Unusual Presentation of Iron-Deficiency Anemia: An Autobiographical Case Report

Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal disorders and the use of proton-pump inhibitors has become the mainstay of treatment for many patients. While these are the most effective medications for the management of GERD, there are several side effects that patients may experience with their use. This autobiographical case report describes the development of iron-deficiency anemia (IdA) with chronic use of omeprazole. The patient was a 35-year-old male with a history of essential hypertension and GERD who was taking omeprazole 40 mg daily for 3 years for the management of reflux symptoms. He developed some mild exercise intolerance and began noticing an affinity for unusual smells, including gasoline and dust, which prompted an evaluation. Lab work demonstrated IdA to 8.3 g/dl, which was not corrected by oral iron supplementation. Sources of gastrointestinal bleeding, Helicobacter pylori infection, and other hypersecretion syndromes were ruled out. IV iron response was transient and only after 8 months of discontinuation of omeprazole did the anemia correct on its own. Omeprazole has increasingly become recognized as a cause of IdA, but only three clinical case reports have been documented in the literature. At least two mechanisms may be involved, and the discontinuation of omeprazole may correct the anemia in 2 months in mild cases, but up to 8 months in more severe cases. The presence of an abnormal propensity for unusual smells, similar to pica as seen in other IdAs, was a unique feature of this case and should prompt evaluation.