Identification

• Kidney stones are hard clumps of minerals and acid salts that have been concentrated enough to form a small ball.
  
  

Types

• There are four types, distinguished by the main component of the kidney stone: calcium, struvite, uric acid and cystine stones.
  
  

Causes

• Kidney stones can occur for many reasons, the most common of which is an imbalance in the fluids and minerals that make up urine. Bodily problems involving the removal of calcium, which most commonly forms stones, are also a cause.
  
  

Symptoms

• Symptoms of kidney stones do not show until the stone moves into your ureter. At this point, pain that can last 20 to 60 minutes begins to emanate from your back and side, nausea occurs and urine can be bloody.
  
  

Treatment

• Most kidney stones will pass through the urine as long as plenty of water is taken in. If a stone gets lodged or is too big, a doctor can remove it with a small instrument, or ultrasound can be used to shatter the stone so that it will pass more easily.