Abstract: TH-PO671
Don't Forget About Trace Minerals: A Rare Case of Erythropoietin-Resistant Anemia
Session Information
- Anemia and Iron Metabolism
November 03, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Anemia and Iron Metabolism
- 200 Anemia and Iron Metabolism
Authors
- Yanik, Andrew, University of Utah Health, Salt Lake City, Utah, United States
- Abraham, Josephine, University of Utah Health, Salt Lake City, Utah, United States
- Lavasani, Tooran, University of Utah Health, Salt Lake City, Utah, United States
Introduction
Erythropoietin (EPO) resistant anemia is a problem often encountered in patients with end stage renal disease (ESRD), and a rare cause of this is copper deficiency. We report the case of a patient with EPO resistant anemia attributable to zinc induced copper deficiency.
Case Description
A 69-year-old male with ESRD due to type I diabetes mellitus on intermittent hemodialysis and darbepoetin for anemia was referred to hematology for EPO resistant anemia as well as pancytopenia. Notably, he also followed with ophthalmology for a history of acute angle closure glaucoma. His hemoglobin had ranged from 9.0-12 g/dL for a period of about three years. Six months prior to referral, he was admitted for a hip fracture complicated by severe anemia with a hemoglobin to 6.2 g/dL. There was no evidence of blood loss and anemia was attributed to ESRD. His hemoglobin had remained at 6.5-8 g/dL despite an escalating dosing of erythropoietin and pancytopenia was noted, prompting referral to hematology. Labs were pertinent for hyperzincemia to 124 ug/dL (ref 60-120) with hypocupremia to 20.6 ug/dL (ref 70-140). On further investigation, he was noted to have been taking a multivitamin regimen prescribed by ophthalmology that contained 160 mg of daily zinc. This was held and copper supplementation was initiated. Repeat studies later revealed zinc and copper to be normal at 90.9 ug/dL and 88.8ug/dL respectively. His hemoglobin has remained 10-12.1 g/dL since.
Discussion
EPO resistant anemia is not uncommon for patients with ESRD on dialysis, and hypocupremia is an underreported etiology. Zinc deficiency is reported in up to 80% of patients with ESRD and is therefore often supplemented. Zinc competes with other metals at the metallothionein protein receptor in the small intestine. In the setting of hyperzincemia, this receptor upregulates as a homeostatic mechanism and copper’s higher affinity for the receptor promotes its binding and ultimate loss in the stool, causing hypocupremia. As illustrated in the case presented here, zinc induced copper deficiency is a clinically relevant cause of EPO resistant anemia in ESRD.