Cystinosis is a complex disease in which the amino acid cystine gets into the cells, but has no transporter out. Because of the defect in transportation, the cell crystallizes causing early cell death. Cystine accumulation also causes severe complications—including muscle wasting, blindness, difficulty swallowing, neurological deterioration, decreased pulmonary function, diabetes, and hypothyroidism. In essence, cystine accumulates in each and every cell of the body, creating a head-to-toe hazard.
Cystinosis slowly destroys the organs in the body, including the kidneys, liver, eyes, muscles, and brain. The earliest abnormality is in the kidneys.
Cystinosis is an extremely rare disease, affecting fewer than 500 people in the United States. A person has a 1 in 4 chance of inheriting it from his or her parents when they both carry the gene for this disease.
Macrophage with Cystine Crystals
Treatment
Cystinosis is treated symptomatically. Renal tubular dysfunction requires a high intake of fluids and electrolytes to prevent excessive loss of water from the body (dehydration). Sodium bicarbonate, sodium citrate, and potassium citrate may be administered to maintain the normal electrolyte balance. Phosphates and vitamin D are also required to correct the impaired uptake of phosphate into the kidneys and to prevent rickets. Carnitine may help to replace muscular carnitine deficiency.
The only specific treatment for Cystinosis is cysteamine. It is the only drug that slows the progression of the disease by removing the cystine from the cells. In 1994, the new product Cystagon TM was made available in capsule form, however it has a very bad taste and smell and must be taken every six hours, every day, without fail. Although this has led to a much better future for children and young adults with Cystinosis, Cystagon TM is very hard on their bodies and is not a cure. In addition to Cystagon TM patients take other medications to control the side effects of the drug. Some patients find it impossible to take the Cystagon TM four times a day at six hour intervals for their entire lives. Others can not tolerate the Cystagon TM.
Cysteamine eye drops help dissolve cystine crystals on the cornea. In patients with severe photophobia, using these drops every hour while awake can remove the cystine crystals from the cornea. A pharmaceutical company is proposing these drops for FDA approval.
Tina's daily dose of medication
Medications only slow the disease, there is no cure!
