T HE HALLMARK of childhood cystinosis is the generalized deposition of cystine crystals in various organs.1 Ophthalmologically, corneal and conjunctival deposits in this disease afford a convenient means of diagnosis on slit-lamp biomicroscopy. Birefringent fusiform bodies and rectangular crystalline forms have been observed in histologic preparations of affected eyes by light microscopic examinations.2,3 Crystals in the conjunctival tissue have also been identified by x-ray diffraction as L-cystine4; however, crystals in the cornea and in other ocular tissues have not been similarly characterized. X-ray diffraction studies correlated with microscopic observations of eye tissues from patients with both childhood and adult cystinosis are the basis of this report.
Method and Materials
Eyes were obtained at autopsy from two patients with childhood cystinosis. Conjunctival biopsies were obtained from two adult cases of cystinosis, and from one of them a 3-mm corneal lamellar button was removed from the lower outer quadrant