A, prevention recommendations: simple carbonate apatite stones are relatively rare, the ten-year recurrence rate is about 50% to 60%. Preventive measures are as follows: 1. Drink plenty of water Drink at least 2000 ml of water daily (equivalent to a thermos bottle) to ensure that the daily urine volume of more than 2000 ml; 2. Limit sodium and salt Sodium salt can cause increased urinary calcium excretion, so daily consumption of sodium chloride (salt) should not exceed 5 grams, avoid MSG, chicken essence; 3. 4, moderate exercise is conducive to the discharge of small stones, but should prevent excessive exercise leading to dehydration resulting in urine concentration; 5, weight control obesity is prone to stone formation, obese people should reduce weight; 6, regular physical examination annual routine review of the urinary ultrasound. In case of multiple recurrence, attention should be paid to exclude renal tubular acidosis or hyperparathyroidism.