Severe retinitis pigmentosa with posterior staphyloma in a family with c.886C>A p.(Lys296Glu) RHO mutation.

ABSTRACT

Background: Posterior pole staphylomata (PSS) is an outward bulging of ocular wall, rarely reported in association with inherited retinal degenerations. Patients and methods: We report a large French family of Jewish ancestry with a peculiar form of dominant retinitis pigmentosa (RP) and posterior pole staphyloma (PPS). Eight members were clinically and genetically examined. Results: All affected members complained of night blindness from early childhood and their ERGs were extinguished in the first decade of life. Seven out of eight presented PPS on fundus examination and SD-OCT. The youngest patient did not present PPS at 11 months of age, but the signs of posterior pole bowing became evident at age 8 years. There was no association between the presence of PPS and refraction. Patients with PPS were either hyperopic or myopic, but all have a high with-the-rule astigmatism. A myopic shift was observed for all of them at follow-up. In this family, the disease segregated with the c.886A>G mutation in RHO gene. Conclusion: A PPS development was observed in initially non-myopic patients of a family with unusually severe dominant RP. The PPS concerned only the area with relatively preserved outer retinal layers (outer nuclear layer and ellipsoid zone). How the outer retina could guide choroid and scleral remodelling remains unclear.