Outcomes of screening for hydroxychloroquine retinopathy at the Manchester Royal Eye Hospital: 2 years' audit

Abstract

Background: The Royal College of Ophthalmologists has produced guidelines for screening for hydroxychloroquine retinopathy. New imaging modalities had suggested an increased prevalence of retinopathy compared with previous reports. The aim of this study is to identify the real-life prevalence of hydroxychloroquine retinopathy in patients attending Manchester Royal Eye Hospital screening service over a 2-year period using The RCOphth diagnostic criteria.

Methods: Data were collected prospectively from all patients attending Manchester Royal Eye Hospital hydroxychloroquine screening service over the audit period. Results of Humphrey visual field tests, spectral-domain optical coherence tomography and fundus autofluorescence were collected as well as data on dose, indication, duration of treatment, and additional risk factors. Cases were identified as having definite, possible, or no retinopathy based on the 2018 RCOphth criteria. The data are not publicly available due to information that could compromise research participant privacy and confidentiality but are available upon request from the corresponding author.

Results: 910 patients attended for screening. 566 were identified as being at risk of retinopathy (543 had been on treatment >5 years, 10 had renal impairment, 12 were on doses of >5 mg/kg/day, and one was concurrently on tamoxifen). The prevalence of HCQ retinopathy was 10/910 (1.09%) of all those screened, and 1.76% of those at risk (10/566). Six patients of those deemed at risk were identified as having definite hydroxychloroquine retinopathy, while four had possible retinopathy.

Conclusions: Our results show a prevalence of retinopathy largely consistent with reports from regional audits yet reveal a far lower estimate compared to previously reported figures.

Fig. 1. A case with moderate HCQ toxicity.

Patient was referred from the Rheumatology Unit with a history of SLE and has been using hydroxychloroquine at the dosage of 200 bd for 16 years. Fundus autofluorescence images (top) shows a semi-circle parafoveal ring of hyper-autofluorescence. OCT scans passing through the fovea (A1 and A2) show a subtle outer retinal change nasal to the fovea. Scans passing through the hyper-AF areas show significant outer retinal structural changes with thinning. Visual field (10-2) below shows areas of focal visual field loss in both eyes.

Fig. 2. A case showing mild HCQ toxicity.

Patient was referred from the Rheumatology Unit with a history of SLE and has been using hydroxychloroquine at the dosage of 200 bd for more than 5 years. The patient had history of chronic renal disease with acute kidney injury and an estimated glomerular filtration rate of 37 mL/min/1.73m2. Fundus autofluorescence images (top) show a subtle increase in signal in parafoveal regions. OCT scans passing through the fovea (middle) show a subtle outer retinal change nasal to the fovea with an area of thinning in the left eye. Visual field (10-2) (bottom) shows areas of visual field loss in both eyes.