Kidney stones, also called renal calculi or nephrolithiasis, are aggregates of crystals that can form “stones” anywhere in the urinary tract. There are several different substances that can cause the problem, the commonest of which contain calcium. Many stones are small enough to pass through the urinary tract undetected, but if one is large enough to get stuck in one the ureters that connect the kidney to the bladder, that will cause real trouble. Passage of a kidney stone is said be one of the most painful things a person can endure. The pain may occur in the back toward one side over the kidney area, or even in the abdomen or groin, and it is often excruciating. Other symptoms may include blood in the urine, fever and vomiting. Unfortunately, recurrence is common.
Treatment at first consists of pain medication and a large fluid intake, an attempt to wash out the stone. Drugs known as alpha-blockers may help to dilate the ureter. Failing that, a device called a lithrotripter may be used for what is called extracorporeal shock-wave lithotripsy. It is an external device that sends focused shock waves (actually sound waves) that pass harmlessly until they strike the stones causing them to break up and become small enough to pass painlessly in the urine. A more invasive procedure is sometimes necessary. Prevention depends on the composition of the stone which can be determined after its remnants pass, but daily ingestion of lots of fluids is the first recommendation. Prophylactic medications may for example includethiazides, potassium citrate or orthophosphate for calcium stones; allopurinol, potassium citrate or sodium bicarbonate.for uric acid stones. Diuretics (water pills) may also be used.