POS1397 HYDROXYCHLOROQUINE INDUCED RETINAL TOXICITY IN PATIENTS WITH RHEUMATIC DISEASES

Abstract

Background:Retinal toxicity from hydroxychloroquine (HCQ) is rare, but the vision loss maybe irreversible and could have medicolegal consequences.Objectives:To determine the prevalence and assess the predictors of retinal toxicity due to HCQ in patients with rheumatic diseases. There is paucity of literature on retinal toxicity due to HCQ in rheumatic diseases.Methods:A retrospective observational study was conducted in the Department of Clinical Immnuology and Rheumatology, Sri Ramachandra Institute of Higher Education and Research,Chennai, India from November 2018-May 2020, on patients taking HCQ for more than 6 months. All patients underwent ophthalmological screening at baseline and every 6 months, and thereafter by modern day screening methods-Humphrey Visual Field (HVF)10-2, Spectral Domain Optical Coherence Tomography(SD-OCT), except for patients with evidence of suspected retinal toxicity at baseline.Fundus autofluorescence (FAF) was done in feasible patients.Results:9 out of 743(1.2%) patients were identified to have retinal toxicity, detected via fundus examination (n=9), SD-OCT (n=8/9), HVF 10-2 (n=6/9), FAF (n=1/9). 55.5% (n=5/9) had Rheumatoid Arthritis(RA) and 44.4% (n=4/9) had Systemic Lupus Erythematosus(SLE) as their primary diagnosis. 77.7% (n=7/9) were females. The mean age was 47.5 years (20-72 years).75%(n=3/4) of SLE patients were below 30 years of age. The average daily and cumulative dose of HCQ in these 9 patients were 244 mg (200-400mg) and 311.22g(73-730g)respectively, whereas the mean recommended dose as per real body weight was 287.2mg/day. Average duration of HCQ consumption was 3.6 years (1-10 years).Only 11.1% (n=1/9) had presented with visual complaints of black floaters.Conclusion:The asymptomatic nature of this irreversible toxicity, warrants frequent screening.Retinal toxicity was not age-related.Toxicity was manifested at low daily and cumulative doses.Screening should be done atleast every 6 months by fundus examination.Objective tests like HVF and SD-OCT should be done annually, especially in patients with underlying rheumatic diseases.The early manifestation of retinal toxicity in young SLE patients could have a genetic association and needs further evaluation.