RetINal Toxicity And HydroxyChloroquine Therapy (INTACT): protocol for a prospective population-based cohort study.

PURPOSE: Hydroxychloroquine (HCQ) is an important medication for patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and other rheumatic diseases. Although it is well-tolerated and cost-effective, the risk of HCQ retinal toxicity is of increasing concern. The aim of this study is to re-examine the HCQ retinal toxicity incidence rate, risk factors and clinical course after discontinuation. METHODS: We designed a prospective population-based cohort study in adult patients with SLE or RA, currently receiving HCQ for five or more years, who are residents of British Columbia (BC), Canada. Based on administrative data, we identified 5508 eligible participants (1346 SLE and 4162 RA). They will participate in annual or biannual retinal screening over 5 years in alignment with the recently revised American Academy of Ophthalmology guidelines. To standardise procedures for retinal screening, imaging, diagnostic criteria, severity staging and data transfer, a consensus meeting was convened in December 2019 with participation of BC retinal specialists and the research team. Agreement was attained on: use of spectral domain-optical coherence tomography as the primary objective screening modality; classification of images into categories of normal, equivocal or abnormal; and transferring the equivocal and abnormal images plus corresponding subjective test results via cloud-based server from each clinic to a reading centre. Confirmation of HCQ retinal toxicity diagnoses and severity staging will be performed by three independent and masked reviewers. The incidence of HCQ retinal toxicity will be calculated, accounting for the competing risk of death. Hazard ratios for each risk factor will be calculated for the risk of HCQ retinopathy, after adjusting for confounders. We will also estimate the risk of HCQ retinal toxicity progression over 5 years. ETHICS AND DISSEMINATION: This study has received approval from the University of British Columbia Clinical Research Ethics Board (H20-00736) and the Vancouver Coastal Health Research Institute.

Visual outcome and rehabilitation in a case of bilateral acanthamoeba sclerokeratitis.

PURPOSE: To report a rare and complicated case of bilateral Acanthamoeba sclerokeratitis (ASK). METHODS: Case report of a 42-year-old patient who was referred to the Massachusetts Eye and Ear Infirmary 7 months after a history of culture-confirmed bilateral Acanthamoeba polyphaga sclerokeratitis. At the time of referral to the MEEI, he was noted to have iris neovascularization and chronic mydriasis in both eyes. The anterior chambers were shallow, and there were mature cortical cataracts that obscured the posterior pole in both eyes. His visual acuity in both eyes was limited to hand motions. RESULTS: The patient underwent sequential cataract extraction, penetrating keratoplasty (PK), and yttrium-argon-garnet laser capsulotomy of the right eye over a span of 3 months. This treatment substantially improved the vision in his right eye to 20/400. Cataract extraction surgery and a PK have been scheduled for this patient's left eye in the near future. CONCLUSIONS: Some patients with ASK and apparently poor visual prognosis can achieve substantial visual improvement after anterior-segment surgery. This report describes the management and outcome of only the second reported case of bilateral ASK in the world.