Copper-deficiency anemia and neutropenia during zinc maintenance therapy for Wilson disease associated with persistent strict dietary copper restriction.

Zinc acetate is an established maintenance therapy for Wilson disease as it reduces intestinal copper absorption. However, excessive dietary copper restriction during zinc therapy may contribute to clinically significant copper deficiency. We report a case of copper-deficiency anemia and neutropenia in a woman in her 60s with Wilson disease, hepatic and neurological involvement, and cirrhosis. Three years after transitioning to zinc maintenance therapy, leukopenia and neutropenia reappeared, followed by macrocytosis, and anemia rapidly worsened. At presentation, the neutrophil count was 378/µL, mean corpuscular volume 120.9 fL, and hemoglobin 4.4 g/dL. On detailed dietary history, persistent strict dietary copper restriction was identified, including long-term avoidance of copper-rich foods. After discontinuation of strict copper restriction, red blood cell transfusion, and zinc acetate reduction from 150 to 100 mg/day, hemoglobin stabilized at approximately 10 g/dL, neutropenia improved, and macrocytosis resolved. This case highlights that cytopenia during zinc maintenance therapy for Wilson disease should not be attributed solely to hypersplenism and that dietary practices should be reassessed because persistent strict dietary copper restriction may contribute to iatrogenic copper deficiency.