MAY 04, 2022
Screening and imaging of patients who had taken pentosan polysulfate (PPS) within 5 years showed specific abnormalities associated with the retinopathy of PPS toxicity.
In this cross-sectional study from the University of Wisconsin-Madison, 78 eyes of 39 participants who were current or recent users of PPS therapy were screened for retinopathy after undergoing a comprehensive eye exam, a medical questionnaire, and imaging. Outcome measures included visual acuity, dosage, duration of PPS exposure, and prevalence of retinal toxicity detected on multimodal imaging, which included color fundus photography, fundus autofluorescence, and spectral domain-OCT (SD-OCT).
Of 145 patients who met the inclusion criterion of having taken PPS within the last 5 years, 39 consented to participate in the study. Mean ETDRS (Early Treatment Diabetic Retinopathy Study) classification was 85 letters in both eyes for all participants and mean Snellen visual acuity was 20/22. Thirty-one percent of eyes demonstrated definitive toxicity with abnormalities in OCT and FAF and 10% of eyes showed questionable toxicity with changes in FAF and SD-OCT. The 41% prevalence of PPS retinopathy in this study is higher than previously reported by others. OCT abnormalities demonstrated disruption of the interdigitation zone, ellipsoid zone, and the retinal pigment epithelium. Changes in the fundus showed hypoautofluorescence, hyperautofluoresecence, and mixed appearance mostly in the central subfield but at times extending beyond the arcades. There were peripapillary abnormalities detected as well.
Screening rate of 27% may have led to an overestimation of retinal toxicity due to sampling bias. Participants who volunteered to be part of the study were more likely to have vision problems as well as higher duration of exposure to PPS. No genetic studies were performed to rule out inherited retinal diseases that could masquerade as PPS toxicity.
There may be a high prevalence of PPS toxicity in patients exposed to this medication. Multimodal imaging, including autofluorescence and OCT, should be part of routine screening for patients on this oral therapy for an extended period of time.