Abstract
Purpose: :
To assess decreased retinal function associated with high cumulative doses of hydroxychloroquine using microperimetry (MP).
Methods: :
Thirteen patients were referred for evaluation of hydroxychloroquine retinal toxicity. Controls were 30 normal eyes of 30 patients referred for a variety of conditions in the other eye. Visual symptoms, duration of treatment, daily hydroxychloroquine dose (milligrams and milligrams per kilogram), cumulative dose, condition for which the drug was taken, visual acuity, Ishihara test, amsler test, retinal examination, visual fields (Octopus 101, Haag-Streit AG, Switzerland) were performed. Lesion-related macular sensitivity and retinal fixation were investigated with an advanced, automatic microperimeter (MP1 Microperimeter, Nidek technologies, Italy).
Results: :
All 26 eyes presented visual acuity of 20/20, Ishihara test unremarkable, 24/26 patients have unremarkable Amsler test, one patient presented Amsler Test positive for metamorphopsias. Three patients (6 eyes) with a low lifetime dose (< or =438 g) of hydroxychloroquine (group 1) had normal retinal sensitivity in both eyes with Octopus and MP1 (mean dB: 32.3vs19.3). Six patients (12 eyes) with a lifetime dose (< or =1500g) of hydroxychloroquine (group 2) had normal retinal sensitivity in one or both eyes with Octopus (mean dB:30.21) and decreased retinal sensitivity in both eyes with MP (mean dB:15.5). Four patients (8 eyes) with a lifetime dose (< or = 2000g) of hydroxychloroquine (group 3) had decreased retinal sensitivity in one or both eyes with Octopus and with MP (mean dB: 23.25 vs 11.46). Among this last group one patient with bilateral bull’s eye maculopthy showed a bilateral central scotoma with Octopus and with MP1. In 3 patients with decreased retinal sensitivity from group 3 hydrossicloroquine was discontinued and three months later repeat MP-1 showed normal sensitivity with resolution of the patient’s visual complaints.
Conclusions: :
Functional testing of the retina with MP results sensitive to detect retinal toxicity in patients on hydroxychloroquine referred for screening evaluation. Several patients have been identified with early maculopathy not detected by standard visual field testing.
Keywords: antibiotics/antifungals/antiparasitics • drug toxicity/drug effects