# A Case of Hydroxychloroquine Toxicity as Evidenced by Visual Field Changes

## TL;DR

An 83-year-old patient on long-term hydroxychloroquine developed retinal toxicity, showing the need for regular eye exams to detect early visual changes.

## Contribution

Highlights the importance of vigilance in detecting retinal toxicity in long-term hydroxychloroquine users through visual field monitoring.

## Key findings

- Visual field changes consistent with retinal toxicity were observed in an 83-year-old patient.
- Subtle visual field depression was detected two years prior, emphasizing the need for periodic ophthalmologic exams.
- The case underscores the importance of baseline and ongoing monitoring for early signs of toxicity.

## Abstract

Hydroxychloroquine sulfate (Plaquenil®) is a disease-modifying anti-rheumatic drug (DMARD) utilized in the management of autoimmune diseases. While its immunomodulatory actions offer therapeutic benefits, a rare complication, hydroxychloroquine-induced retinal toxicity, poses a significant concern. We present the case of an 83-year-old patient with cutaneous lupus undergoing periodic hydroxychloroquine screening for eight years. Visual field changes consistent with retinal toxicity were observed. Chart review revealed subtle visual field depression two years prior. This highlights the importance of vigilance toward unexplained visual changes and subtle changes on ophthalmologic examination in hydroxychloroquine-treated patients. Our findings underscore the necessity of baseline and periodic ophthalmologic examinations with particular attention paid to visual field depression or deficit that might occur without macular changes. Additionally, we address the choice between red and white visual field testing. This case contributes to the understanding of hydroxychloroquine-induced retinal toxicity, emphasizing the importance of comprehensive ophthalmologic surveillance in long-term users.