Retinal histopathology of a carrier of X-chromosome-linked retinitis pigmentosa.

Autopsy eyes were examined from a 79-year-old female carrier of X-chromosome-linked retinitis pigmentosa. At age 78 years, she had no visual symptoms but had intraretinal bone spicule pigmentation in the nasal and inferior periphery of both eyes. Rods, cones, and pigment epithelium in the central retina appeared normal. In the midperiphery, patches with advanced photoreceptor cell degeneration were observed overlying pigment epithelium containing melanolysosomes. Within these patches, rods and cones were reduced in number or absent, and pigment epithelial cells abutted the external limiting membrane. A precipitous decline in rod nuclei was observed in transitional zones between areas of apparently normal photoreceptors and areas of absent photoreceptors. In the far periphery, large areas lacked photoreceptors and pigment epithelium. Histopathologic findings in this elderly carrier are compared with those previously described in a 24-year-old man with X-chromosome-linked retinitis pigmentosa.