A previously undescribed pigmentary disturbance of the peripheral fundus was seen in eleven patients with childhood cystinosis. Histologic observations in two of these children demonstrated that extensive degeneration and loss of retinal pigment epithelium was associated with the retinopathy. The peripheral fundus abnormalities may be of special diagnostic value since it can precede the classical corneal deposits of cystine crystals as suggested by the present study. The existence of this retinopathy appears to be peculiar to childhood cystinosis as it was found to be absent in the adult form of the disease.
Wong VG, Lietman PS, Seegmiller JE. Alterations of Pigment Epithelium in Cystinosis. Arch Ophthalmol. 1967;77(3):361-369. doi:10.1001/archopht.1967.00980020363014