Copper Deficiency Mimicking Myelodysplastic Syndrome: A Case Report.

Copper deficiency can mimic myelodysplastic syndrome, a group of heterogeneous hematopoietic disorders characterized by peripheral cytopenias, with potential progression to bone marrow failure and acute myeloid leukemia. We present the case of an 83-year-old female with a history of Graves' disease, early-stage hormone receptor-positive breast cancer, hypertension, and glaucoma, who presented with fatigue and progressive lower extremity weakness. Laboratory tests revealed macrocytic anemia, neutropenia, and lymphopenia, with normal platelet counts. Bone marrow biopsy showed trilineage hematopoiesis, dyserythropoiesis, ring sideroblasts, and vacuoles in erythroid precursors, indicating copper deficiency. The patient had been using zinc oxide paste for dentures and had increased her zinc intake during the COVID-19 pandemic, leading to severe copper deficiency. Treatment with intravenous and oral copper supplementation resulted in marked improvement in hematologic indices and symptoms. This case underscores the importance of considering copper deficiency in the differential diagnosis of cytopenias and myeloneuropathy in elderly patients, particularly those with a history of excessive zinc intake.