What is a kidney stone?
A stone forms in the kidney when there is an imbalance between certain urinary components (chemicals such as calcium, oxalate and phosphate) that promote crystallization and others that inhibit it. The most common stones contain calcium in combination with oxalate and/or phosphate. [Anatomical drawing of a kidney with kidney stones]

What are the symptoms of a kidney stone?
Generally, the initial symptom of a kidney stone is extreme pain. The pain often begins suddenly as the stone moves in the urinary tract, causing irritation and blockage. You will feel a sharp, cramping pain in your back (in the area of your kidney) or in your lower abdomen, which may spread to your groin. You may also experience blood in your urine, nausea and/or vomiting. Occasionally, stones do not produce any symptoms. However, even if a stone is not large enough to cause symptoms, it can still trigger a dull ache, which is often mistaken for muscle or intestinal pain.

If the stone is too large to pass easily, the pain will continue as the muscles in the wall of the ureter try to squeeze the stone along into the bladder. You may feel the need to urinate more frequently or experience a burning sensation during urination. If the stone is close to the lower end of the ureter at the opening into the bladder, you may feel as if you have not fully completed urination.

How are kidney stones diagnosed and treated?
The diagnosis and treatment of kidney stones is the same as that of ureteral stones.

[Read more about kidney stones]

Other Kidney Disorders