Chloroquine and hydroxychloroquine toxicity is classically associated with which retinal finding?

Chloroquine and hydroxychloroquine toxicity is classically associated with which retinal finding?

• A. Bullseye maculopathy
• B. Whorl keratopathy
• C. Optic neuropathy
• D. Cotton wool spots

Answer: (A)

The main idea is that this drug class causes a distinctive macular toxicity pattern: bullseye maculopathy. Chloroquine and hydroxychloroquine accumulate in the retina, damaging photoreceptors and the RPE in a ring around the fovea. As the outer retina thins and the ellipsoid/photoreceptor integrity is lost in that parafoveal ring, the central fovea is often relatively spared early on, producing a circular ring of retinal change. On exam and imaging, this creates the classic bullseye appearance around the fovea. This macular pattern is the hallmark of chloroquine/hydroxychloroquine retinopathy and helps differentiate it from other ocular findings. In contrast, whorl keratopathy reflects corneal deposits and does not indicate retinal toxicity. Optic neuropathy would present with optic nerve findings and visual-tract issues rather than a macular bullseye pattern. Cotton-wool spots point to retinal nerve fiber layer ischemia from systemic vascular disease, not the retinal toxicity associated with these antimalarials.

The main idea is that this drug class causes a distinctive macular toxicity pattern: bullseye maculopathy. Chloroquine and hydroxychloroquine accumulate in the retina, damaging photoreceptors and the RPE in a ring around the fovea. As the outer retina thins and the ellipsoid/photoreceptor integrity is lost in that parafoveal ring, the central fovea is often relatively spared early on, producing a circular ring of retinal change. On exam and imaging, this creates the classic bullseye appearance around the fovea. This macular pattern is the hallmark of chloroquine/hydroxychloroquine retinopathy and helps differentiate it from other ocular findings.

In contrast, whorl keratopathy reflects corneal deposits and does not indicate retinal toxicity. Optic neuropathy would present with optic nerve findings and visual-tract issues rather than a macular bullseye pattern. Cotton-wool spots point to retinal nerve fiber layer ischemia from systemic vascular disease, not the retinal toxicity associated with these antimalarials.