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MULTIMODAL IMAGING IN DEFEROXAMINE-RELATED OCULAR TOXICITY: RAPID DEVELOPMENT DUE TO SUPRATHERAPEUTIC DOSING AND
Elisah M Huynh1, Mahmood Khan2, Yanhan Ren1
1Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts.
Retinal Cases & Brief Reports
|March 11, 2025
Summary
Deferoxamine can cause progressive retinal damage, including RPE changes and photoreceptor loss, even after dose reduction or stopping the medication. This toxicity impacts vision in patients with iron overload conditions.
Area of Science:
- Ophthalmology
- Pharmacology
- Hematology
Background:
- Deferoxamine is a chelating agent used to treat iron overload, common in patients with beta-thalassemia.
- Supratherapeutic doses of deferoxamine can lead to serious adverse effects, including ocular toxicity.
- Understanding the progression of deferoxamine-induced retinal toxicity is crucial for patient management.
Purpose of the Study:
- To characterize the evolution of deferoxamine-related retinal toxicity.
- To assess the impact of dose reduction and cessation on toxicity progression.
- To investigate the reversibility of deferoxamine-induced ocular changes.
Main Methods:
- Observational clinical case report.
- Detailed patient history including beta-thalassemia and blood transfusion requirements.
- Ophthalmic examination to assess visual acuity and visual fields.
Main Results:
- A 59-year-old female experienced peripheral visual field loss and nyctalopia after supratherapeutic deferoxamine doses.
- Progressive retinal pigment epithelium (RPE) thickening and photoreceptor loss were observed.
- Vision declined from 20/25 and 20/30 to 20/60 and 20/50 despite dose reduction.
Conclusions:
- Deferoxamine use can cause RPE changes, thickening, and photoreceptor loss.
- These ocular toxicities may progress even after reducing the deferoxamine dosage or discontinuing the drug.
- The findings highlight the potential for irreversible vision impairment due to deferoxamine toxicity.
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