Guerra Angela, Meschi Tiziana, Allegri Franca, Schianchi Tania, Adorni Giuditta, Novarini Almerico, Borghi Loris
Department of Clinical Sciences, University of Parma, Parma, Italy.
Clin Chem Lab Med. 2004 Jan;42(1):45-50. doi: 10.1515/CCLM.2004.009.
Centrifuged and filtered urine is often used to evaluate in vitro the crystallization processes of calcium oxalate (CaOx), but even such simple manipulations can alter the composition of the urine, as regards its protein and lipid concentrations. In urine samples taken from 17 normal male adults, we evaluated CaOx crystallization by simultaneously using three different types of urine: untreated (U), centrifuged at 2000 rpm (800 g) and filtered at 0.22 microm (CF), and centrifuged-filtered and ultrafiltered at 10 000 Da (CFU). The addition of 1.2 mmol/l of oxalate to each type of urine produced notably different results. The total amount of CaOx crystals (expressed as calcium oxalate dihydrate crystals (COD) + oxalate monohydrate crystals (COM) area/total area x 100) was on average 13.2% in U urine, 70.7% in CF urine and 11.1% in CFU urine (CF > U and CFU, U = CFU); the relative prevalence of COD and COM (expressed as COD area/COM area) was on average 71.4 in U urine, 0.0026 in CF urine and 5.5 in CFU urine (U > CF and CFU, CFU > CF); the diameter of COD (expressed in microns) was on average 15.2 in U urine, 3.7 in CF urine and 24.3 in CFU urine (CFU > U and CF, U > CF); the diameter of COM (expressed in microns) was on average 5.2 in U urine, 2.6 in CF urine and 8.9 in CFU urine (CFU > U and CF, U > CF); the total amount of CaOx aggregates (expressed as CaOxAgg area/total area x 100) was on average 8.5% in U urine, 22.1% in CF urine and 2.9% in CFU urine (CF > U and CFU, U > CF). We conclude that CaOx crystallization processes in manipulated urine are extremely different, probably due to changes in macromolecular compounds.
离心和过滤后的尿液常被用于体外评估草酸钙（CaOx）的结晶过程，但即便如此简单的操作也会改变尿液的成分，包括其蛋白质和脂质浓度。在取自17名正常成年男性的尿液样本中，我们通过同时使用三种不同类型的尿液来评估CaOx结晶情况：未处理的尿液（U）、以2000转/分钟（800克）离心并通过0.22微米滤膜过滤的尿液（CF），以及经过离心过滤并以10000道尔顿超滤的尿液（CFU）。向每种尿液中添加1.2毫摩尔/升的草酸盐产生了显著不同的结果。CaOx晶体的总量（以二水草酸钙晶体（COD）+一水草酸钙晶体（COM）面积/总面积×100表示）在U尿液中平均为13.2%，在CF尿液中为70.7%，在CFU尿液中为11.1%（CF＞U和CFU，U = CFU）；COD和COM的相对患病率（以COD面积/COM面积表示）在U尿液中平均为71.4，在CF尿液中为0.0026，在CFU尿液中为5.5（U＞CF和CFU，CFU＞CF）；COD的直径（以微米表示）在U尿液中平均为15.2，在CF尿液中为3.7，在CFU尿液中为24.3（CFU＞U和CF，U＞CF）；COM的直径（以微米表示）在U尿液中平均为5.2，在CF尿液中为2.6，在CFU尿液中为8.9（CFU＞U和CF，U＞CF）；CaOx聚集体的总量（以CaOxAgg面积/总面积×100表示）在U尿液中平均为8.5%，在CF尿液中为22.1%，在CFU尿液中为2.9%（CF＞U和CFU，U＞CF）。我们得出结论，经处理的尿液中CaOx的结晶过程差异极大，可能是由于大分子化合物的变化所致。
