Pupillary-block glaucoma associated with childhood cystinosis

Cystinosis is a rare autosomal recessive metabolic disorder that results in the widespread accumulation of cystine crystals in ocular tissues as well as in bone marrow, liver, spleen, lymph nodes, and kidneys. We treated a case of pupillary-block glaucoma in a 19-year-old woman caused by cystine accumulation in the iris stroma. Trabeculectomy and iridectomy relieved the pupillary block and decreased the intraocular pressure. Histologic examination disclosed the presence of crystals in the conjunctival and iris stroma and in the iris pigment epithelium. Crystals were also found within conjunctival mast cell granules, confirming the lysosomal nature of cystinosis.