EDUCATIONAL REVIEW Cystinosis: the evolution of a treatable disease

Abstract Cystinosis is a rare autosomal recessive disorder involving lysosomal storage of the amino acid cystine due to a defect in the membrane transport protein, cystinosin. Since the introduction of kidney transplants and the availability of cystine-depleting medical therapy, this previously fatal disease was transformed into a treatable disorder. Renal allografts and medical therapy targeting the basic metabolic defect have altered the natural hisotry of cystinosis so drastically that patients have a life expectancy extending past 50 years. Con-sequently, early diagnosis and appropriate therapy are critically important. In this article, we offer a review of themanifestations of cystinosis, including the proximal tubular dysfunction of renal Fanconi syndrome, and discuss the prevention and treat-ment of the disorder’s systemic complications. We focus on the nephropathic forms of cystinosis, aiming to assist nephrologists and other physicians to develop early recognition and appro-priate management of cystinosis patients