What are cystine stones?
A cystine stone is a type of kidney stone. Many people think there is only one type of kidney stone. But in fact, there are different types. A kidney stone is a solid piece of material that forms in a kidney. It may stay in the kidney or travel down the urinary tract.
Cystine stones tend to reoccur and are typically larger than other kidney stones. You should talk to your healthcare provider if you get cystine stones. There are things you can do to lessen your risk of forming new stones. You may not know you have a cystine stone. It is important to have stones diagnosed to help get the right treatment for this condition.
Causes
Cystine stones are caused by a rare disorder called “cystinuria.” The disorder causes a natural substance called “cystine” to leak into your urine. When there is too much cystine in the urine, kidney stones can form. These stones can get stuck in the kidneys, bladder, or anywhere in the urinary tract. Most people with cystinuria have recurring stones. It is a lifelong condition that can be controlled, but not cured.
Who is at risk for cystinuria?
Cystinuria is an inherited disorder. Inherited means it is passed down from parents to children through a defect in a specific gene. In order to have cystinuria, a person must inherit the gene from both parents. About 1 in 7,000 people worldwide have cystinuria. According to a recent study, most people with cystinuria get their first stones in their twenties or thirties with 30-40% of people developing cystine stones in their teens. But some adults have their first cystine stone after age 40. Children can also get cystine stones. In fact, according to some research, 8-10% of kidney stones in children are cystine stones.