To describe how underlying retinal diseases, such as retinitis pigmentosa, increase the risk of chloroquine (CQ)-induced macular toxicity.

A observational case report.

We present the case of a 57-year-old woman being annually followed up in the ophthalmology service because of a systemic treatment with CQ. The explorations were successive normal, until a 10:2 visual field shows central defects in both eyes. Despite CQ treatment is discontinued, 10:2 visual field reveals slowly progressive macular defects. During follow-up, fundus examination disclosed bone spicules in the inferonasal middle periphery: The electroretinogram shows slow amplitude responses under scotopic conditions, and the electrooculogram also shows pathological responses. Therefore, the diagnosis of sector retinitis pigmentosa plus CQ maculopathy is made. Currently, the slow but constant progression of both peripheral and central defects is evident, despite having discontinued CQ treatment more than 15 years ago.

Underlying retinal diseases seem to increase the risk of photoreceptor damage when undergoing a toxic insult. Thus, we hypothesize a potential interplay between retinal dystrophies and toxic maculopathy induced by CQ and the influence of each of them in the evolution and prognosis of the other.

As the world continues to grapple with the novel coronavirus [coronavirus disease 2019 (COVID-19)], many treatments have been proposed to help alleviate the symptoms and reduce the mortality rate. Hydroxychloroquine (HCQ) is an antimalarial drug that is typically used for several autoimmune, rheumatic, and dermatological conditions. It has also been considered to treat and prevent COVID-19 and subsequent arthritis associated with the infection. This drug is known to cause retinal toxicity, which can lead to vision impairment or loss. While the exact mechanism is not yet fully understood, it is thought to be due to the accumulation of the drug in the retinal pigment epithelium. The risk of toxicity increases with long-term use or with high doses of the drug and is more likely to occur in patients with pre-existing retinal diseases or those who are predisposed to retinal diseases. In this context, several steps can be taken to monitor and minimize the risk of ophthalmological adverse events when using HCQ to treat patients with COVID-19.

As the world continues to grapple with the novel coronavirus [coronavirus disease 2019 (COVID-19)], many treatments have been proposed to help alleviate the symptoms and reduce the mortality rate. Hydroxychloroquine (HCQ) is an antimalarial drug that is typically used for several autoimmune, rheumatic, and dermatological conditions. It has also been considered to treat and prevent COVID-19 and subsequent arthritis associated with the infection. This drug is known to cause retinal toxicity, which can lead to vision impairment or loss. While the exact mechanism is not yet fully understood, it is thought to be due to the accumulation of the drug in the retinal pigment epithelium. The risk of toxicity increases with long-term use or with high doses of the drug and is more likely to occur in patients with pre-existing retinal diseases or those who are predisposed to retinal diseases. In this context, several steps can be taken to monitor and minimize the risk of ophthalmological adverse events when using HCQ to treat patients with COVID-19.

Systemic chloroquine/hydroxychloroquine (CQ/HCQ) can cause severe ocular side effects including bull's eye maculopathy (BEM). Recently, we reported higher quantitative autofluorescence (QAF) levels in patients with CQ/HCQ intake. Here, QAF in patients taking CQ/HCQ in a 1-year follow-up is reported.

Fifty-eight patients currently or previously treated with CQ/HCQ (cumulative doses 94-2435 g) and 32 age- and sex-matched healthy subjects underwent multimodal retinal imaging (infrared, red free, fundus autofluorescence [FAF], QAF [488 nm], and spectral-domain optical coherence tomography (SD-OCT). For analysis, custom written FIJI plugins were used for image processing, multimodal image stacks assembling, and QAF calculation.

Thirty patients (28 without BEM and 2 with BEM, age range = 25-69 years) were followed up (370 ± 63 days). QAF values in patients taking CQ/HCQ showed a significant increase between baseline and follow-up examination: 282.0 ± 67.9 to 297.7 ± 70.0 (QAF a.u.), P = 0.002. An increase up to 10% was observed in the superior macular hemisphere. Eight individuals (including 1 patient with BEM) had a pronounced QAF increase of up to 25%. Compared to healthy controls, QAF levels in patients taking CQ/HCQ were significantly increased (P = 0.04).

Our study confirms our previous finding of increased QAF in patients taking CQ/HCQ with a further significant QAF increase from baseline to follow-up. Whether pronounced QAF increase might predispose for rapid progression toward structural changes and BEM development is currently investigated in ongoing studies.

In addition to standard screening tools during systemic CQ/HCQ treatment, QAF imaging might be useful in CQ/HCQ monitoring and could serve as a screening tool in the future.

This cross-sectional internet-based questionnaire aimed to assess the knowledge and experience of autoimmune disease patients in Saudi Arabia of the ocular effects of hydroxychloroquine (HCQ). Among the 245 respondents, discontinuation of the drug was linked to its ocular toxicity in approximately 7.3%. Most patients had taken HCQ for a period longer than five years, exceeding a dose of 5 mg/Kg. A lack of education and physician communication about medication toxicity was reported by approximately 40.8% of the participants. Despite the knowledge about HCQ retinopathy, the drug is prescribed to autoimmune disease patients at an inappropriate dosage. Knowledge obtained from physicians' communication may improve the health outcomes of chronically ill patients. Rheumatologists and ophthalmologists should work together to recognize patients at risk of hydroxychloroquine toxicity and ensure they receive proper education and adhere to periodic follow-up.

To characterize the stability or progression of different stages of hydroxychloroquine (HCQ) retinopathy up to 20 years after stopping the drug.

We reviewed findings from 13 patients with initial HCQ retinopathy classified as early (patchy photoreceptor damage), moderate (ring of photoreceptor thinning or scotoma), or severe (retinal pigment epithelial [RPE] damage). Patients had been off HCQ for as many as 14 years at initial examination and were subsequently followed for 5 years to 8 years with repeated fundus autofluorescence and spectral domain optical coherence tomography.

Early and moderate cases stabilized in fundus autofluorescence appearance, foveal thickness, ellipsoid zone line length, and visual acuity for up to 9 years after stopping HCQ. By contrast, severe cases demonstrated a continual loss of these parameters for up to 20 years off the drug. The presence of RPE damage at initial examination predicted progressive retinopathy over many years.

The steady progression of severe HCQ retinopathy in eyes showing RPE damage after drug cessation suggests a metabolic insult that chronically destabilizes rather than destroys cellular function, with a clinical course resembling that of genetic dystrophies. Our findings stress the importance of early detection to minimize progression and visual loss.