Kidney stones

Symptoms

- Severe pain in the lower back and groin
- Nausea and vomiting
- Blood in the urine, which might only be seen with a microscope
- Recurrent infections of the urinary tract

Exactly what are kidney stones?

Your kidneys filter out chemicals, wastes, and fluids that your body does not need. Some of these chemicals do not dissolve well and form crystals in the urine. Small crystals pass from the kidneys to the bladder. However, sometimes the crystals are larger, and cannot pass easily through the urinary tract. A clump of crystals of un-dissolved material in the urinary system is a stone. There are many substances that can make up a stone. A stone blocking the urinary system can be painful and dangerous.

Evaluation

A urologist can examine your urine under a microscope to check for blood, crystals, and infection. X-rays can help locate a stone and determine its size. X-rays without dye (contrast) can determine if the stone is blocking a kidney. An ultrasound exam can sometimes determine size and location of a stone. At other times, more complex tests may need to be done.

Treatment

Sometimes drinking lots of water and taking pain medication will help you pass the stone. The success of this treatment depends mainly on stone size and location. Smaller stones have an excellent chance of passing themselves. Other times, kidney stones can be broken up with an ultrasonic shock wave technique called a lithotripsy. This grinds the stones into a powder to be passed more easily. This technique does not require an incision and can usually be carried out without anesthesia.

Sometimes the lithotripsy is not an option for patients with large or complex kidney stones. In these cases, the doctor would apply a laser or more powerful ultrasonic form of energy directly to the kidney stone. This is also a procedure that usually requires no incision.

In a few cases, surgical removal of the stone is needed.

Prevention

To prevent kidney stones, drink lots of fluids. The more fluids your kidneys filter, the less likely the chemicals and salts will form into stones. Avoid excesses of calcium in the diet if your stones contain calcium. For people who form many stones, evaluation by a urologist to determine the metabolic cause and possible treatment should be performed.