Bladder stones are defined as hard masses of minerals in the bladder. Highly concentrated urine in the bladder causes urine minerals to crystalize in the forms of bladder stones. Concentrated urine is a result of the inability to completely empty the bladder.

Small bladder stones can sometimes pass on their own while larger bladder stones may need to be removed. If untreated, bladder stones can cause infections and complications.

Symptoms

Bladder stones may not always be symptomatic. However, if the stones block the urine or irritate the bladder the following symptoms may occur:

  • Pain in the lower abdomen
  • Penile pain or discomfort in men
  • Painful urination
  • Frequent urination
  • Blood in urine
  • Difficulty urinating
  • Cloudy or dark-colored urine

Causes

Bladder stones most commonly form due to the inability of the bladder to empty completely. Most cases involve an underlying condition that affects the bladder that may eventually lead to the formation of bladder stones.

Underlying conditions that can cause bladder stones are:

  • Prostate gland enlargement: An enlarged prostate can often cause bladder stones in men. The enlarged prostate can compress the urethra and block urine flow. The interruption of urine flow can cause the bladder to be inable to empty completely.
  • Damaged nerves (neurogenic bladder): If the nerves that direct the bladder muscles to tighten and release are damaged, the bladder may not empty completely. Stroke, spinal cord injuries, diabetes or other health issues can damage the nerves.
  • Inflammation: Inflammation of the bladder can cause bladder stones. The inflammation may be caused by urinary tract infections or radiation therapy to the pelvic area.
  • Kidney stones: Small kidney stones can sometimes travel down the ureters into the bladder and grown into bladder stones if not removed.
  • Medical devices: Bladder catheters or other medical objects such as a stent or a contraceptive device that have traveled to the bladder by accident can cause bladder stones. The bladder stones usually form on the surface of the devices.

Risk factors

Risk factors for bladder stones include the following conditions:

  • Bladder outlet obstruction: Any condition that obstructs the flow of urine out of the bladder to the urethra can be considered as bladder outlet obstruction. The most common cause of bladder outlet obstruction is an enlarged prostate.
  • Neurogenic bladder: In a neurogenic bladder the nerves that control bladder function are damaged by conditions such as a stroke, diabetes, spinal cord injuries, herniated disk or Parkinson’s disease. People with a neurogenic bladder can also suffer from bladder outlet obstruction, which increases the risk of bladder stones.

Complications

Untreated bladder stones can cause complications such as:

  • Chronic bladder dysfunction: bladder stones can cause long-term urinary problems such as pain or frequent urination if left untreated. They can also block the passage of urine from the body by lodging in the opening where urine exits the bladder into the urethra.
  • Urinary tract infections: bladder stones can cause chronic or recurrent bacterial infections in the urinary tract.

Prevention

The underlying condition that usually causes bladder stones is difficult to prevent; however, the following steps can reduce the risk of developing bladder stones:

  • Seeking medical opinion about urinary symptoms that are unusual: Early diagnosis and treatment of a urological condition such as an enlarged prostate can limit or reduce the risk of bladder stones.
  • Drinking plenty of fluids: Large intake of fluids, especially water, can dilute the concentration of minerals in the bladder and possibly prevent the development of bladder stones.