En español In English Contact Us


Cystinosis is a rare, inherited genetic disorder caused by the buildup of cystine, an essential building block of proteins, in different cells of the body. People with cystinosis have a defect in the gene coding for cystinosin, the enzyme that removes cystine from cell storage.  The enzyme may work less than normal or not at all. The excess cystine forms crystals, damaging cells, with the kidneys, eyes and muscles being most affected. There are three types of cystinosis: infantile nephropathic cystinosis, intermediate (late-onset) cystinosis, and non-nephropathic (ocular or “benign”) cystinosis.  Nephropathic cystinosis is the most severe as it can lead to kidney disease and eventual kidney failure.

Cystinosis affects approximately 500 to 600 children in the US, with about 20 new cases diagnosed each year.1

Complications of cystinosis include, but are not limited to, the following:

  • Kidney failure, ultimately necessitating dialysis or transplant
  • Impaired growth
  • Increased urination, thirst, and dehydration
  • Eye pain due to the formation of cystine crystals in the eye
  • Muscle deterioration
  • Sensitivity to light
  • Blindness
  • Inability to swallow
  • Diabetes
  • Thyroid and nervous system problem
  • Infertility in men

Individuals with intermediate cystinosis may not see symptoms until their teens, while symptoms will be apparent in infancy for patients with nephropathic cystinosis. Nephropathic patients typically have several affected organ systems beside the kidney.  In less severe cases, isolated ocular cystinosis can occur, causing eye pain without systemic complications.

Current drug therapy available at Accredo for Cystinosis includes:

  • Procysbi
    • Procysbi is a metabolic agent approved by the US Food and Drug Administration (FDA) for the treatment of nephropathic cystinosis.


Nesterova, Galina, and William Gahl. "Infantile Nephropathic Cystinosis Standards of Care." (2012): 1-9. Cystinosis Research Network. June 2012. Web. June 2014.

Share this page