Kidney stones are pieces of a stone or crystal-like material. These stones form inside the kidneys or other parts of the urinary tract. The kidneys remove waste from the body. They also balance the water and electrolyte content in the blood by filtering salt and water.

There are several types of kidney stones:

  • Calcium oxalate
  • Calcium phosphate
  • Struvite
  • Uric acid
  • Cystine

Kidney Stone
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The cause of your kidney stone may be depend on the type of stone that you have. Calcium stones are the most common type.

  • Calcium oxalate or phosphorus stones—These kidney stones form when the concentration of calcium or other minerals in the urine becomes too high or when minerals that prevent stone formation are too low.
  • Struvite stones—These stones develop as a result of a urinary tract infection. The stones are composed of ammonium, magnesium, and phosphate salts.
  • Uric acid stones—These stones form when urine is acidic. This may also occur in people with gout or those who are on chemotherapy.
  • Cystine stones—These stones form due to a rare genetic disorder that causes the kidneys to build up excess amounts of cystine. Cystine is one of the amino acids that make up proteins.