Background The risk of end-stage retinopathy (bull's eye maculopathy) from hydroxychloroquine is reported as 0.65%. With recent advances in retinal structure and function testing, American Academy of Ophthalmology (AAO) issued revised guidelines to detect early signs of hydroxychloroquine retinopathy with the use of ancillary testing including Optical Coherence Tomography (OCT), Fundus Autoflourescence (FAF) and multifocal Electroretinography (mfERG) in addition to clinical exam and visual fields. Risk of retinopathy as defined by combination of these tests ranges from 7.5–12% in those on HCQ for at least 5 years or longer. This is an expanded cohort of patients previously presented at the 2015 American College of Rheumatology (ACR) meeting in San Francisco, CA.
Objectives To determine the application of AAO guidelines in an academic practice and the prevalence of HCQ retinopathy based on advanced ancillary tests recommended by AAO.
Methods Microperimetry (MP) was used as a substitute for Humphrey Visual Fields (HVF). Ophthalmic exam, MP, OCT, FAF, mfERG were performed on SLE patients meeting SLICC criteria on hydroxychloroquine. Ophthalmic examinations and testing were interpreted by experienced retina specialists.
Results The mean duration of treatment with HCQ was 11.8 years in 125 (246 eyes) consecutive patients with SLE on whom all 4 tests done. Overall, HCQ-related abnormalities were noted in 12 (5%) eyes on OCT, 14 (6%) on FAF, 26 (11%) on mfERG and 24 (10%) on MP. A total of 45 eyes (18%) had abnormal findings on OCT and 12 (27%) of these were related to HCQ. A total of 36 eyes (15%) had abnormal findings on FAF and 14 (39%) of these were related to HCQ. For mfERG, we found a total of 99 (40%) abnormal tests with 26 (26%) eyes with changes consistent with HCQ retinopathy. A total of 72 (29%) of all MP tests were abnormal and 24 (33%) of these were related to HCQ. Only 3 patients (2.4%) showed changes in all 4 tests suggestive of HCQ retinopathy.
Conclusions Our updated series reaffirms our previous findings presented at the ACR conference and demonstrates that in absence of pre-HCQ data for the AAO recommended ancillary tests it may be difficult to interpret changes seen on these tests since most of the screenings are done by regular ophthalmologists who lack the equipment and experience with specialized testing such as mfERG, FAF and OCT. Nonspecific abnormalities are common with these tests, which need careful interpretation by retina specialists. We recommend repeat testing in those with abnormal tests and additional testing in patients in which all four modalities were not used to determine early toxicity. In our expanded cohort, we found substantial number of cases with abnormalities unrelated to HCQ. A discussion needs to take place between the patient care team including the ophthalmologist and rheumatologist to decide about the continuation or stopping HCQ based on these nonspecific abnormalities in individual tests that are not supported by the respective other modalities.
Scholl HP, Shah SM. We need to be better prepared for hydroxychloroquine retinopathy. JAMA Ophthalmol. 2014 Dec;132(12):1460–1.
Disclosure of Interest None declared