The unusual association of inverse retinitis pigmentosa and Fuchs’ heterochromic iridocyclitis

Abstract

BackgroundClassic retinitis pigmentosa (RP) and other syndromic variants have previously been associated to Fuchs’ heterochromic iridocyclitis (FHI). Common immunogenic and inflammatory pathways have been proposed to explain the higher incidence of this uveitic phenomenon in patients with retinal dystrophies without definitive answers. Infrequent variants of RP such as inverse RP have not been previously reported in association with FHI. We believe that finding the way these entities connect can shed some light into their complex pathogenesis and help find ways to foresee and prevent the appearance of complications such as cataract and macular edema.Case presentationWe present a 15 year old mexican male with history of nyctalopia and rapid, progressive visual loss since infancy who had profound hyper and hypopigmented retinal pigment epithelium changes in the posterior pole together with pigment clumping in the macula of both eyes and an electroretinogram pattern consistent of rod-cone dystrophy. He was diagnosed with inverse RP. Three years after his first visit he was found to have a mild asymptomatic non granulomatous anterior uveitis in the right eye with fine stellate keratic precipitates and subtle iris stromal atrophy not associated with iris synechiae and without evidence of posterior uveitis or findings consistent with infectious etiology. Findings were consistent with FHI. As the patient was normotensive, the lens was transparent and there was no clinical evidence of macular edema, the patient was kept under observation without treatment.ConclusionsPatients with RP are prone to develop chronic, low grade inflammation responses similar to the ones present in FHI. This association makes us believe that immunogenetic pathways involved in the degenerative process that leads to photoreceptor loss may become a target in the prevention and treatment of inflammatory complications in RP and disease progression. It also suggests FHI may be a triggered response predisposed by an unidentified genetic factor that may be related to genes affected in RP and thus be identified before irreversible complications such as glaucoma occur.

Retinitis Pigmentosa: Current Clinical Management and Emerging Therapies

“…Some forms of uveitis, such as acute zonal occult outer retinopathy and (atypical) advanced birdshot chorioretinopathy may mimic features of RP, such as pigment clumping and retinal vessel attenuation, which leads to initial misdiagnosis [ 248 , 249 ]. A specific form of uveitis found in patients with RP is Fuchs’ heterochromic uveitis, which has been reported in several case series [ 250 , 251 , 252 , 253 , 254 , 255 , 256 ]. The co-occurrence of uveitis in RP can be coincidental, but there may also be a role for underlying immunological abnormalities that play a role in the disease etiology of RP, which is supported by several animal and immunohistochemical studies [ 247 , 250 , 257 , 258 ].…”

Uveitis Anterior Asociado a Retinitis Pigmentosa: Reporte de un Caso

“…Se describe que la inmunidad de tipo celular y humoral, responde hacia los antígenos retinianos en pacientes con RP, provocando una reacción inflamatoria leve y crónica. 1,5 La uveitis en pacientes con RP es poco frecuente, pero no rara. Varios estudios inmunohistoquímicos apoyan la hipótesis.…”