Pigmentary Maculopathy in Interstitial Cystitis/Bladder Pain Syndrome Treated with Oral Pentosan Polysulfate: A Review

Abstract

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a rare and chronic bladder condition. Pentosan polysulfate sodium (PPS) is the only oral medication approved specifically for the management of IC/BPS. In 2018, Pearce et al. reported for the first time a unique pattern of ocular pigmentary maculopathy exclusively in IC/BPS patients following PPS exposure. This publication triggered several published studies, case reports, case series, and media reports claiming a link between PPS and pigmentary maculopathy; however, a clear interpretation of these data is still awaited and there are currently no prospective, well researched, confirmatory data available. The clinical presentation of pigmentary maculopathy is characterised by moderate visual impairments and macular hyperpigmented spots, yellow-orange deposits, and/or patchy retinal pigment epithelium (RPE) atrophy. Most patients experiencing this ocular effect used high doses of PPS over an extended period, with risk of pigmentary maculopathy associated with PPS increasing with exposure. Studies that rule out prevalent retinal abnormalities are lacking. The cause of this particular maculopathy remains unclear and further research is required. The current data suggest that a median duration of 15 years of PPS exposure must elapse before pigmentary maculopathy is detected. Furthermore, no increased incidence of any type of maculopathy is found up to a median duration of 5 years of PPS use. Thus, in line with the current European Medicines Agency (EMA) recommendation, if patients respond to therapy and a decision is made to continue PPS for longer than 6 months, a fundoscopy with optical coherence tomography (OCT) and fundus autofluorescence should be performed. In cases of no findings, the next eye examination should be after a further 5 years of PPS use; in cases of findings, continuation of the treatment should be re-evaluated by the urologist and monitored by yearly ocular fundus examinations. This review provides a framework for evidence-based treatment with PPS in patients with IC/BPS using appropriate monitoring and gives an overview of the current understanding and evidence of the association of PPS and a specific pigmentary maculopathy.