Cystinuria

Cystinuria facts

  • Cystinuria is a relatively common inherited disorder.
  • The disorder is due to a defect in the transport of amino acids including one called cystine.
  • Cystinuria features too much cystine in the urine.
  • Cystine is highly insoluble, precipitates out of solution and forms stones in the urine.
  • All the signs and symptoms of cystinuria are due to the stones.
  • The stones cause blood in the urine, pain, and obstruction and infection of the urinary tract.
  • The foremost aim of treatment is to prevent the formation of cystine stones.
  • Cystine stones can often be dissolved and new ones prevented by a high fluid intake.
  • People with cystinuria should understand that "for them, water is a necessary drug."

What is cystinuria?

Cystinuria is an inherited (genetic) disorder of the transport of an amino acid (a building block of protein) called cystine resulting in cystinuria (an excess of cystine in the urine) and the formation of cystine stones.

How frequent is cystinuria?

Cystinuria is one of the more common genetic disorders. Its overall prevalence is about 1 in 7,000 in the population.

Cystinuria is the most common defect known in the transport of an amino acid.

What is a transport defect?

Within the body, many molecules are able to pass across the membranes that surround cells. These molecules can accomplish this feat due to specific transport systems. These systems include special receptors on the membrane of the cell and special carrier proteins. The receptor recognizes the molecule and receives it on the cell membrane. Then the molecule hitches a ride through the cell membrane on the back of a carrier protein.

With such remarkable specificity, it is little wonder that sometimes there are defects in transport systems. Several dozen different diseases are now known to be due to transport defects.

Medically Reviewed by a Doctor on 1/15/2014

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Cystinuria - Symptoms Question: What were your symptoms associated with cystinuria?
Cystinuria - Treatment Question: What kinds of treatment were effective for cystinuria? How did you keep track of your fluid intake?

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