Cystinosis is a severe autosomal recessive lysosomal storage disease with an estimated incidence of ±0.5-1.0 per 100,000 live births. The disease is caused by bi-allelic mutations in the CTNS gene that encodes the lysosomal cystine transporter cystinosin. More than 100 mutations have been reported to date. The most severe and frequent form, affecting ~95% of patients, is termed infantile nephropathic cystinosis; patients generally develop clinical symptoms related to renal Fanconi syndrome during the first year of life and progress to end-stage renal disease during the second decade of life, despite treatment with cysteamine, a compound that allows cystine efflux from lysosomes. In time, and in particular if not treated appropriately with cysteamine, other symptoms develop including ocular symptoms related to corneal cystine crystal deposits, hypergonadotropic hypogonadism, pancreatic insufficiency, hepatomegaly, splenomegaly, muscle atrophy and weakness, oral dysfunction, pulmonary insufficiency, and various central nervous system symptoms.
Overall, the prognosis of the disease has improved considerably with the treatment with cysteamine. With this treatment, an increasing number of patients are now becoming adults and adult physicians need to learn how to treat this disease and its complications. The lecture will provide an overview of the disease and of current treatments.