Background: Irreversible maculopathy and retinopathy are well-known adverse effects of chloroquine and hydroxychloroquine. For this article the literature was screened for relevant risk factors. The results were used for recommendations concerning the extent and frequency of ophthalmological monitoring.
Methods: A systematic literature review was undertaken.
Results: Very few studies on a high evidence level could be retrieved for this problem. Most of the risk factors have not been addressed sufficiently. A higher dosage per kg body mass, long therapy duration, presence of keratopathy and renal or hepatic dysfunction are probably associated with an increased risk to develop a maculopathy/retinopathy. Additional factors such as age, genetic disposition, additional retinal disease, sunlight exposition and nature plus duration of the underlying disease have not sufficiently been demonstrated. Gender, body mass and even the accumulated dosage do not contribute as risk factors according to current knowledge.
Conclusion: Beside patient risk factors, the spectrum of ophthalmological methodology and cost considerations have to be considered when thinking about content and frequency of monitoring for the risk of acquiring a (hydroxy)chloroquine-induced maculopathy or retinopathy. In principle, a baseline examination comprising visual acuity (near and far), 10 degree threshold perimetry, colour vision, slit lamp (cornea) and funduscopy is reasonable. One of the high investment techniques such as multifocal ERG, fundus autofluorescence and high resolution optical coherence tomography should be used depending on the existing equipment and experience but not more often than once a year. In suspicious cases or high risk-patients a flexible approach is mandatory.
(c) Georg Thieme Verlag KG Stuttgart-New York.