Urinary or Kidney stones are hardened mineral deposits that gather on the way from the renal pelvis in the kidney to the bladder. These originate as microscopic particles and over the course of time develop into stones. Medically this condition is known as nephrolithiasis, or renal stone disease. The kidneys filter waste products from the blood and adds them to the urine. When waste materials in the urine do not dissolve completely and the kidney is unable to evacuate them, crystals and kidney stones are likely to form. Some stones may pass out of the kidney or get lodged in the ureter (tube that carries urine from the kidney to the bladder), and cause severe pain that starts from the lower back and radiates to the side or groin.
Kidney stones can provoke a severe, sudden pain if they move along the ureter, the tube leading from the kidneys, and they can cause a lot of health problems if they block the flow of urine. The pain can often be accompanied by vomiting. If they move into the ureter (the tube from the kidney to the bladder) they cause intense pain and blood in the urine. A lodged stone can block the flow of urine and build a backpressure in the affected ureter and kidney. Increased pressure results in stretching and spasm, which cause severe pain.
Types of Kidney Stones
Calcium stones are the most common type of stones. Calcium is a normal part of a healthy diet and is used by bones and muscles. Calcium not used by the body goes to the kidneys where it is normally flushed out with the rest of the urine. In some people, however, the calcium that stays behind joins with other waste products to form a stone.
Struvite stones are a type of stone that contains the mineral magnesium and the waste product ammonia. It may form after an infection in the urinary system.
Uric Acid Stones
Uric acid stones may form when there is too much acid in the urine.
Cystine stones consist of cystine, one of the building blocks that make up muscles, nerves, and other parts of the body, can build up in the urine and form a stone. Cystine stones are rare. The disease that causes cystine stones (cystinosis) runs in families.