kidney and urinary tract disorders
Stones in the Urinary Tract
Prevention of Urinary Tract Stones
In a person who has passed a calcium stone for the first time, the likelihood of forming another stone is about 15% within 1 year, 40% within 5 years, and 80% within 10 years. Measures to prevent the formation of new stones vary, depending on the composition of the existing stones. Drinking large amounts of fluids—8 to 10 ten-ounce (300-milliliter) glasses a day—is recommended for prevention of all stones. People should drink enough fluid to produce more than about 2 quarts of urine per day. Other preventive measures depend somewhat on the type of stone. People with calcium stones may have a condition called hypercalciuria, in which excess calcium is excreted in the urine. For these people, measures that decrease the amount of calcium in the urine can help prevent formation of new stones. One such measure is a diet that is low in sodium and high in potassium. Overview of Calcium's Role in the Body intake should be about normal—1,000 to 1,500 milligrams daily (about 2 to 3 servings of dairy per day). The risk of a new stone forming is actually higher if the diet contains too little calcium, so people should not try to eliminate calcium from their diet. However, people may need to avoid sources of excess calcium such as antacids that contain calcium. Thiazide diuretics, such aschlorthalidoneorindapamide, also reduce the concentration of calcium in the urine in such people.Potassium citratemay be given to increase a low urine level of citrate, a substance that inhibits calcium stone formation. Restricting dietary animal protein may help reduce urinary calcium and the risk of stone formation in many people with calcium stones. People who have calcium stones are more likely to develop other stones if their diet has too little or too much calcium. A high level of oxalate in the urine, which contributes to calcium stone formation, may result from excess consumption of foods high in oxalate, such as rhubarb, spinach, cocoa, nuts, pepper, and tea, or from certain intestinal disorders (including some kinds of weight loss surgery).Calcium citrate,cholestyramine, and a diet that is low in fat and in oxalate-containing food may help to reduce urinary oxalate levels in some people.Pyridoxine(vitamin B6) decreases the amount of oxalate the body makes. In rare cases, when calcium stones result from Hyperparathyroidism , Uric acid stones are almost always caused by excessive acid levels in the urine.Potassium citrateshould be given to all people who have uric acid stones to make the urine alkaline and neutralize the high acid levels that cause uric acid stones. Occasionally, a low animal protein diet orallopurinolmay be used to reduce uric acid levels in the urine. Maintaining a large fluid intake is also very important. For stones made of cystine, urinary cystine levels must be kept low by maintaining a large fluid intake and sometimes taking alpha-mercaptopropionylglycine (tiopronin) orpenicillamine. People with recurrent struvite stones may need to take antibiotics continually to prevent Overview of Urinary Tract Infections (UTIs) . 