Cause of formation and its harm! The formation process of the kidney is the result of the increase in the concentration of the crystal substance in urine, the solubility of the worker is decreased, and the crystal is in a state of over saturation. In this process, the formation of urinary crystal material over saturated state and the reduction of the formation of the formation of inhibitor in urine are the most important two factors.
(a) the formation of the saturated state in the urine is too little; the absolute excretion of some substances in urine is too much, such as calcium, oxalate, uric acid, cysteine and phosphate, etc., urinary pH changes. Urinary pH decreased (5. 5), when the uric acid saturation was increased, the urine pHT was increased, the calcium phosphate, magnesium phosphate and uric acid sodium saturation increased; urinary pH changes had little effect on the saturation of calcium oxalate. Sometimes too saturated state is short, after a meal or a decrease in urine volume in the short time of certain substances in the urine volume increased by. So the measurement of 24 hours urine volume and certain material urine volume can not help determine whether transient saturated state.
(II) in urine crystallization inhibitors reduce normal urine contains some substances that inhibit the formation and growth of crystalline, such as pyrophosphate suppressing the formation of calcium phosphate crystals; mucin, citric acid and magnesium inhibited calcium oxalate crystal formation. These substances in urine will reduce the formation of stones.
(three) the nucleation of homogeneous nucleation of a crystalline form. Taking calcium oxalate as an example, when the saturation state occurs, these two ions form crystallization, the higher the ion concentration, the greater the crystallization.
Smaller crystallization of the outer appearance of the body of the ions are constantly shedding, studies suggest that only when the crystallization of more than 100 ion containing only enough affinity to crystallize the appearance of the ion does not fall off, so as to achieve a state of equilibrium, crystallization can continue to grow. At this time, the ion concentration is lower than the crystal just formed. Heterogeneous nucleation is similar to the shape of the two crystals, and one kind of crystallization can be used as the core to promote the aggregation and growth of the other crystals on the surface. Such as uric acid sodium crystallization can promote the formation and growth of calcium oxalate crystal. In urine after the formation of crystallization and stay in the local growth is conducive to the development of stone. A lot of crystals and small stones can be washed out by the flow of urine in vitro. When some factors such as local stenosis, obstruction and so on lead to urinary obstruction or slow, it is conducive to the formation of stone.
(four) organic matrix can promote the formation of a certain shape of the stone. But it does not play a key role in the formation of stone.
