Information on Cystine Stone
Cystine stone is a rare type of kidney stone, which is caused by an uncommon and inheritable medical condition known as "cystinuria". Unlike other kidney stone types that normally develop in people aged 20 to 60 years, cystine stone occurs in young adults and children. While there is no cure for cystine stone, there is available treatment although it may be more complicated than usual methods.
Cystine is an amino acid. The kidneys process cystine, like other amino acids, by filtering it first into the urine and then reabsorbing them back to the blood. However, a person with cystinuria has defective kidneys with reduced ability to take the cystine back from the urine and because this substances that does not dissolve completely in urine, crystals will form to develop into stones.
Like with other types of kidney stones, the common symptoms of a person with a cystine stone is pain but the difference with this one is the pain is more constant and persistent. Some of the strong indications of the presence of a cystine stone, aside from the age of the sufferer, is a strong history of kidney stones in the family. An x-ray may be used to make the diagnosis but a cystine stone is not as bright as calcium stone and hence, may not be noticed so the doctor may request that you take a CT Scan or another type of an x-ray exam known as IVP that produces shaper images than regular x-ray. Additionally, the urine will be tested to check for hexagon-shaped crystals and a high amount of cystine.
It is important to diagnose and treat cystine stone because it poses complications such as urinary blockage and infections. Conservative measures are always the first form of treatment for cystine stone. The aim is to lower the level of cystine concentration in the urine. This is done by increasing daily fluid intake into at least three liters. Bicarbonate or citrate is usually used to increase the pH level in the urine. The patient is also advised to lower the intake of sodium.
Medications are the next consideration in the treatment of cystine stone if conservative methods do not work. Doctors may prescribe any of the three - captopril (least side effects, least effective), tiopronin (lesser side effects, not commonly available), and penicillamine (common but has many potential side effects).
If the above treatment options still do not work, the doctor will recommend a medical procedure to remove the cystine stone. Shock wave lithotripsy is the usual procedure done to treat kidney stones but it is not that effective in treating this type of stone, especially if the size of the cystine stone is larger than 1.5 centimeters. In such a case, an invasive technique is preferable to break up the stone or stones. It is very rare for doctors to perform open surgery.
The truth is, treatment of cystine stone is very difficult Patients can expect to experience an average of 1 to 2 episodes every year if treated conservatively. However, the development of kidney failure because of multiple cystine stones is rare.
