Bladder stones are crystalline masses that form from the minerals and proteins, which naturally occur in urine. These types of stones are much less common than kidney stones. Bladder stones can form anywhere in the urinary tract before depositing in the bladder. They begin as tiny granules about the size of a grain of sand, but they can grow to more than an inch in diameter. These stones can block the flow of urine causing pain and difficulty with urination. They can also scratch the bladder wall, which may lead to bleeding or infection
While the exact causes of the formation of bladder stones are not completely understood, bladder stones usually occur because of urinary tract infection (UTI), obstruction of the urinary tract, enlargement of the prostate gland in men, or the presence of foreign bodies in the urinary tract. Diet and the amount of fluid intake also appear to be important factors in the development of bladder stones.
Ninety-five percent of all bladder stones occur in men, most of who have an enlarged prostate gland or a UTI. These stones are rarely seen in children or in African Americans. People with gout may develop bladder stones composed almost entirely of uric acid.
The symptoms of bladder stones may become evident when the wall of the bladder is scratched or when the urinary tract becomes obstructed by the stone. These symptoms include:
- Abnormally dark colored urine
- Blood in the urine
- Difficulty urinating
- Painful urination
- Frequent urge to urinate
- Lower abdominal pain
- Pain or discomfort in the penis