上尿路结石化学成分分析及意义

Analysis and significance of upper urinary stones′chemical compsition

目的分析上尿路结石核心、中层、外周样本的化学成分,并探讨其意义。方法取35枚直径>0.8 cm的尿路结石,分别取其核心、中层、外周样本,采用傅立叶变换红外光谱(FT-IR)法分析其化学成分。结果纯尿酸结石4枚,混合结石31枚。24例以草酸钙为主要成分的结石核心样本中草酸钙质量分数为55.6%±9.7%,磷酸钙为33.3%±7.6%;中层样本分别为81.4%±8.6%,14.2%±2.8%;外周样本分别为86.9%±9.1%,8.7%±2.6%。7例以磷酸钙为主要成分的结石核心样本中草酸钙质量分数为7.2%±1.1%,磷酸钙为75.7%±12.7%;中层样本分别为23.6%±2.4%,66.4%±9.4%;外周样本分别为52.9%±7.6%,47.1%±7.5%。不同部位结石样本中草酸钙和磷酸钙质量分数相比P均<0.05。不同部位结石样本中草酸钙和磷酸钙质量分数相比P均<0.05。4例纯尿酸结石核心、中层、外周样本均由纯尿酸或尿酸盐组成,无其他成分。结论上尿路结石以混合性结石为主,最常见的成分为草酸钙与磷酸钙,其质量分数在不同层面间存在显著差异,其中磷酸钙晶体较容易出现在结石的核心,而草酸钙更易存在于外表面。磷酸钙晶体很可能是混合结石形成的共同初始原因。感染是磷酸钙晶体形成原因之一。

Objective To study the composition of nuclear,middle and external layers of the upper urinary stones,and make the further investigation of its significance.Methods The fragments were selected from the nuclear,middle and external layers of 35 stones of which diameter were more than 8 mm.They were further analyzed by Fourier transform infrared spectroscopy（FTIR）.Results 4 cases of uric acid calculus were pure stone and mixed stones were found in 31 cases.The contents of calcium oxalate and calcium phosphate in the nuclear layers were 55.6%±9.7% and 33.3%±7.6% in respectively;in the middle layers were respective 81.4%±8.6% and 14.2%±2.8%;the contents in the outer layers were respective 86.9%±9.1% and 8.7%±2.6% in 24 calcium oxalate stones.The contents of calcium oxalate and calcium phosphate in the nuclear layers were 7.2%±1.1% and 75.7%±12.7% in respectively;in the middle layers were respective 23.6%±2.4% and 66.4%±9.4%;in the outer layers were respective 52.9%±7.6% and 47.1%±7.5% in 7 calcium phosphate stones.The contents of calcium oxalate and calcium phosphate crystals in different layers were fairly variable（P0.05）.The different layers of the uric acid stones were consisted of crystallization of uric acid and urate rarely containing other compositions.Conclusions Mixed stones which contain calcium oxalate and calcium phosphate are prone to be found of the upper urinary stones and the compositions vary in different layers of the stone.Calcium phosphate crystal is prone to be found in the nuclear layer,while calcium oxalate tends to exist in the external layer of the mixed stone.Calcium phosphate crystal probably is the incipient substance of all mixed stones,and infection is one reason causing Calcium phosphate crystal.