ABSTRACT
OBJECTIVE: To report the effect of hydroxychloroquine therapy cessation on the multifocal electroretinogram (mfERG) in a case series of patients with rheumatic disease suspected to have retinopathy. METHODS: Comprehensive data were retrospectively reviewed on 14 patients from a total of 50 cases who discontinued hydroxychloroquine due to suspected toxicity. Patients were followed for 4 years after the cessation of therapy. mfERG testing had been part of original screening for hydroxychloroquine retinopathy and was continued after therapy cessation at 6-month intervals. Descriptive statistics, independent sample t test, and one-way analysis of variance with repeated measures and post hoc analysis were conducted to determine patients' clinical characteristics and changes in the mfERG after therapy cessation, respectively. RESULTS: All 14 patients were female; 12 were treated for rheumatoid arthritis and 2 for systemic lupus erythematosus. Three groups were identified: (i) 9 patients in whom the responses of the mfERG recovered to within normative values after cessation of hydroxychloroquine therapy, (ii) 3 who experienced limited recoveries, and (iii) 1 patient whose mfERG response was unchanged. There was no significant difference (p > 0.05) in the clinical characteristics of these patients. However, the proportional reduction of mfERG ring 1, 2, and 3 amplitudes from age normal responses at the time of discontinuation of drug use for the first and second groups of patients was significantly different, with more reduction in group 2 (p < 0.05). CONCLUSION: Early detection of hydroxychloroquine retinopathy through screening and subsequent therapy discontinuation could result in recovery of the mfERG ring amplitude response and preservation of visual function.
