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Screening for Hydroxychloroquine and Chloroquine Retinopathy

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Abstract

Screening for 4-aminoquinoline retinopathy (4AQR) became common internationally in the 1960s when inappropriately high doses of chloroquine were often prescribed. As knowledge of toxic thresholds increased and hydroxychloroquine supplanted chloroquine, the prevalence of 4AQR declined. As a result, professional guidelines discouraging screening were published in the United Kingdom. In the United States, guidelines continue to recommend screening. In 2011, those guidelines added the use of multifocal electroretinography (mf ERG), spectral domain optical coherence tomography (SD-OCT), and fundus autofluorescence (FAF) to the list of recommended tests. Such additional testing comes at considerable added expense. Screening for overdosing, which is common, is rational in all settings. Screening for 4AQR in properly dosed patients is probably a waste of resources.

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Abbreviations

4AQR:

4-Aminoquinoline retinopathy

4AQs:

4-Aminoquinolines (chloroquine and hydroxychloroquine)

ABW:

Actual body weight

AG:

Amsler grid

C:

Chloroquine

HC:

Hydroxychloroquine

IBW:

Ideal body weight

RA:

Rheumatoid arthritis

RPE:

Retinal pigment epithelium

SLE:

Systemic lupus erythematosus

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Browning, D.J. (2014). Screening for Hydroxychloroquine and Chloroquine Retinopathy. In: Hydroxychloroquine and Chloroquine Retinopathy. Springer, New York, NY. https://doi.org/10.1007/978-1-4939-0597-3_9

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