Evaluation of toxic retinopathy caused by antimalarial medications with spectral domain optical coherence tomography

Abstract

Purpose: To investigate the frequency of toxic retinopathy in patients with lupus erythematosus and rheumatoid arthritis with long-term use of chloroquine diphosphate or hydroxychloroquine through spectral domain optical coherence tomography and the outcomes of ophthalmological exams (visual acuity - Snellen's table, color vision test - Ishihara's table, fundoscopy, and retinography - red-free).

Methods: A cross-sectional study was carried out involving the ophthalmologic evaluation of patients using regular chloroquine diphosphate or hydroxychloroquine for a period of 1 year or longer. The patients completed a questionnaire on their opinions and treatment regularity. The same patients underwent ophthalmologic examination and spectral domain optical coherence tomography.

Results: The prevalence of toxic retinopathy caused by antimalarials was 4.15% (9 of 217 patients), 7.4% (4 of 54 patients) following chloroquine diphosphate usage, and 0.82% (1 of 121 patients) following hydroxychloroquine usage. Only patients with advanced stage maculopathy presented abnormalities during the ophthalmologic exam: the color vision test was altered in 11.1%, and visual acuity and fundoscopy were altered in 33.3%. Identification of early toxic retinopathy, detected in six patients, was possible using spectral domain optical coherence tomography. The mean duration of antimalarial drug usage among patients with toxic retinopathy was 10.4 years. Only 31% of the patients reported some symptoms during treatment, and although 24% were afraid to use the medication, they did so as prescribed.

Conclusion: Use of spectral domain optical coherence tomography was essential for the diagnosis of early-stage antimalarial toxic retinopathy in patients with the following characteristics: asymptomatic, antimalarial use 7 days a week for a period of more than 5 years, and normal clinical ophthalmologic examination.