Kidney stones are a hard build-up of minerals in the kidneys.
There are five main types of kidney stones:
- Calcium oxalate stones: These usually form when there is too much oxalate or calcium in the urine.
- Calcium phosphate stones: These occur depending on the urinary pH level.
- Struvite stones: These often occur following recurrent UTIs.
- Uric acid stones: These are formed when there is too much uric acid in the urine.
- Cystine stones: These are the rarest type and are associated with a condition called cystinuria.
Kidney stones can travel down the ureter, into the bladder and are then passed out of the body. When the stones become too big, however, they can become stuck and cause severe pain.