To the Editor:

We read with interest Zaidi et al.’s “How to set up a Hydroxychloroquine Retinopathy Screening Service” [1]. The authors describe establishing a hydroxychloroquine retinopathy screening service in a major NHS university teaching hospital with over ~1500 patients on hydroxychloroquine.

We report the feasibility and challenges of implementing a hydroxychloroquine retinopathy screening service in a smaller district general hospital and results from the largest dataset of hydroxychloroquine retinopathy screening in the UK to date.

West Suffolk Hospital NHS Foundation Trust in Bury St Edmunds, UK has ~900 patients on hydroxychloroquine. As a result, we realised we were not able to implement the full Royal College recommendations and decided to screen only high-risk patients as defined by the guidelines [2].

We also decided to screen visual fields at baseline so that at 5 years, any pre-existing pathology can be accounted for and patients would not have to unnecessarily stop hydroxychloroquine. Our service has been set up to accommodate six patients per week (~300 patients per year) with one healthcare assistant and one ophthalmic science care practitioner. Each patient has a visual acuity (LogMAR), an automated 10-2 Octopus Visual Field, pupil dilation, Heidelberg OCT, and blue field Fundus Autofluorescence with a 55° lens.

Our data from the first 100 patients show no signs of hydroxychloroquine toxicity. Average treatment duration was 7.3 years and the longest use was 21 years. Forty-five patients were deemed high risk and were brought back for annual review and 16 were discharged after initial baseline screening. Nine patients required repeat visual field examination due to unreliable visual fields. Previously undiagnosed co-pathology was identified in ten patients.

Our challenges included that 50% of patients “did not attend” the service and 60% rescheduled appointments. There is also no regional access to multi-focal electroretinography.

In summary, our initial data does not support the high prevalence rates of hydroxychloroquine retinopathy described by the guidelines [2]. Hydroxychloroquine retinopathy screening is possible in a smaller district general hospital, however multiple challenges arise with limited resources and discussions with the local Clinical Commissioning Group should take place to fund screening programmes.