Why does my teenage daughter keep getting kidney stones? she's just gone to the hospital for her third kidney stone. is this a sign of something more serious?

Children : Children that form kidney stones, especially multiple, usually have one or more of a variety of problems. For children that have normal urinary tracts (normal kidneys, normal ureters, and normal bladders) most of these children that do not have known syndromes or medical conditions will have underlying metabolic disorders that affect the way the kidneys filter and process minerals. Some children have low citrate levels, some have high oxalate, and some have other conditions. It is critical to evaluate the stones composition and the 24 hour urine studies on a child with kidney stones and especially with a child that has multiple kidney stones. It must be determined that the child has normal urinary tracts and any other syndrome or conditions that predispose to stones.

Kidney : Kidney stones occur when microscopic mineral deposits crystallize in your urine and gradually grow until they become large enough to move, which causes excruciating pain. Once you form a kidney stone, the risk for forming another within ten years can be as high as 50%. The risk for recurrent stones is higher in people who have certain metabolic disorders (hyperparathyroidism, renal tubular acidosis, cystinuria, gout), autoimmune diseases (sarcoidosis), recurrent urinary tract infections caused by specific organisms (proteus, klebsiella, ureaplasma), or who don't take measures to reverse the conditions that lead to stone formation. Seventy percent of kidney stones are composed of calcium oxalate. Other stone types (uric acid, struvite, calcium phosphate, and cystine) are less common. Avoidance of oxalate-containing foods (chocolate, strawberries, tea, spinach, rhubarb, etc) and adequate hydration (try for at least 2 quarts of urine output daily) will prevent most calcium oxalate stones. Interestingly, calcium restriction does not prevent kidney stones and may even increase your risk for forming some types of stones. A moderate-calcium diet is associated with the lowest incidence of stones. Your doctor may also recommend urine alkalinizing agents, such as potassium citrate, or other medications, depending on the type of stones your daughter forms. It is vital that you submit a kidney stone for analysis, if possible. This can help determine the best way to prevent future recurrences. People who have recurrent kidney stones usually undergo further evaluation to rule out metabolic problems. Ask your doctor if further workup is needed and what additional measures you can take to prevent future episodes of kidney stones. Good luck!