Cystinosis (cystine storage diseas) is a rare autosomal recessive inherited disorder in which cystine crystals accumulate within the cells. The gene is located on the short arm of human chromosome 17. Different types of cystinosis are recognized: infantile cystinosis [ cystinosis - infantile], childhood (nephropathic) cystinosis [cystinosis - childhood], juvenile cystinosis [cystinosis - juvenile], and adult cystinosis [cystinosis - adult]. In cystinosis tinsel-like, fine white crystals appear in the subepithelial conjunctival tissue. The crystals are insoluble in absolute ethanol but soluble in many other solutions. There is a widespread accumulation of cystine crystals in bone marrow, liver, spleen, lymph nodes, and kidneys. Plasma cystine and cysteine levels are not consistently elevated. Childhood cystinosis, the most severe form, is associated with defective renal tubular reabsorption and the Fanconi syndrome. Renal failure is common in childhood cystinosis. A tissue biopsy of affected tissue can establish the diagnosis. Other conditions that are associated with corneal crystals need to be distinuished from cystinosis. They include monoclonal gammapathy of uncertain significance, multiple myeloma, Schyder corneal dystrophy, infectious crystalline keratopathy. The eye is not affected in cystinuria, which it is sometimes confused, with cystinosis.