Kidney stones (renal lithiasis) are small, hard deposits that form inside your kidneys, which are made of mineral and acid salts, most commonly calcium oxalate. Kidney stones have many causes. The most common reason for stone formation is dehydration, which allows minerals to crystallize and stick together.

Kidney stones cause pain when urine is blocked and unable to pass to the bladder. Many people have asymptomatic stones in their kidneys because urine flow is often not obstructed when a stone is within the kidney. However, when a kidney stone moves out of the kidney into the ureter (the tube connecting the kidney to the bladder), then it may block urine flow and cause pain. The pain of a kidney stone typically starts in your side or back, just below your ribs, and moves to your lower abdomen and groin. The pain may change as the kidney stone moves through your urinary tract.

Signs and symptoms of an active kidney stone include the following:

• Severe pain in the side and back, below the ribs
• Pain that spreads to the lower abdomen and groin
• Pain on urination
• Pink, red or brown urine
• Nausea and vomiting
• Persistent urge to urinate
• Fever and chills if an infection is present

Prevention of future kidney stones is an important part of our treatment plan. In fact, almost 50% of patients will form another stone if they do not make some preventative changes. Many patients can reduce future stones with dietary changes and increased fluid intake. Patients at high risk for recurrence (multiple stones, large stones, family history of kidney stones) are encouraged to complete a special urine test at home (24-hour test) to allow for identification and correction of factors causing stones. Some patients will benefit from vitamins or medications depending on the results of their testing.

Many kidney stones will pass and can be managed with increased fluid intake and intermittent pain medication. Unfortunately many will not pass and require intervention.