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Ocular toxicity of hydroxychloroquine
1Department of Ophthalmology, Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong.
Hong Kong Medical Journal = Xianggang Yi Xue Za Zhi
|August 17, 2006
Summary
Hydroxychloroquine (HCQ) retinopathy is rare but serious. Early screening is key to detect ocular toxicity, as stopping HCQ is the only effective management.
Area of Science:
- Ophthalmology
- Rheumatology
- Pharmacology
Background:
- Hydroxychloroquine (HCQ) is widely used for autoimmune conditions.
- Ocular toxicity, particularly retinopathy, is a significant concern associated with HCQ use.
- Understanding HCQ ocular toxicity is crucial for patient safety and effective disease management.
Purpose of the Study:
- To review the types, incidence, pathogenesis, risk factors, and clinical characteristics of hydroxychloroquine ocular toxicity.
- To discuss current screening and management strategies for HCQ retinopathy.
- To highlight the challenges in defining and managing HCQ-induced ocular complications.
Main Methods:
- Comprehensive literature search of Medline database up to May 2005.
- Inclusion of original articles and review papers.
- Keywords: 'hydroxychloroquine', 'chloroquine', 'ocular', 'toxicity', 'retinopathy', 'screening'.
Main Results:
- HCQ ocular toxicity encompasses keratopathy, ciliary body and lens involvement, and retinopathy.
- True HCQ retinopathy is rare (<50 reported cases), but carries significant visual consequences.
- Risk factors include dosage, duration, renal/liver disease, age, and concomitant retinal conditions. Clinical signs include visual disturbances and characteristic fundoscopic changes.
- Screening for early, reversible premaculopathy is recommended, though consensus on optimal methods and frequency is lacking.
Conclusions:
- Limited consensus exists regarding the definition, screening, and management of HCQ retinopathy.
- Early detection through regular screening may allow for intervention to prevent irreversible vision loss.
- Management decisions, including drug cessation, require collaboration between ophthalmologists and the managing physician.
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