Abstract：
Creatinine is the end product of the catabolism of creatine and creatine phosphate. Creatine phosphate serves as a reservoir of high-energy phosphate, especially in skeletal and cardiac muscle. Besides typical known changes in serum and urinary creatinine concentrations, rare cases associated with changes in serum and urinary creatine levels have been described in the literature in humans. These cases are mostly linked to an excessive intake of creatine ethyl ester or creatine monohydrate, often resulting in increased urine creatinine concentrations. In addition, it is known that at such elevated creatinine concentrations, creatinine crystallisation may occur in the urine. Analysis of crystals and urinary concrements, often of heterogenous chemical composition, may provide diagnostic and therapeutic hints to the benefit of the patient. The aim of the present work was to analyze urine crystals of unclear composition with microscopic and spectroscopic techniques. On routine microscopic analysis of urine, a preliminary suspicion of uric acid or creatinine crystals was expressed. The crystals were of a cuboid shape and showed polarization effects in microscopy. The dried urine sample was whitish-orange in colour, odourless and dissolved well in water. Protein concentration in dry weight (DW) urine was about 0.3 mg/mg. The measured zinc content in the studied sample was approximately 660 µg/g DW sample and copper content was approximately 64 µg/g DW sample. A lead signal of around 10 µg/g DW sample was also observed. UV-Vis analysis showed a maximum creatine peak around 220 nm, compatible with the spectrum of creatinine with a maximum peak of 230 nm. Using HPLC technique, an extreme high ratio of creatine to creatinine of about 38 was measured, which led to the conclusion of the occurrence of rare creatine crystals in urine.
摘要：
肌酸酐是肌酸和磷酸肌酸分解代谢的最终产物。磷酸肌酸作为高能磷酸盐的储集层,尤其是骨骼肌和心肌。除了典型的已知的血清和尿肌酐浓度变化，在人类文献中已经描述了与血清和尿肌酸水平变化相关的罕见病例。这些病例大多与过量摄入肌酸乙酯或肌酸一水合物有关,常导致尿肌酐浓度升高。此外,众所周知，在如此高的肌酐浓度下，肌酐结晶可能发生在尿液中。晶体和尿结石的分析，通常是异质的化学成分，可以为患者的利益提供诊断和治疗提示。本工作的目的是用显微镜和光谱技术分析组成不清楚的尿液晶体。在尿液的常规显微镜分析中，初步怀疑尿酸或肌酐结晶.晶体为长方体形状，在显微镜下显示出极化效应。干燥的尿液样本颜色为白色橙色，无臭和溶解在水中。干重(DW)尿中的蛋白质浓度为约0.3mg/mg。所研究样品中测得的锌含量约为660μg/gDW样品，铜含量约为64μg/gDW样品。还观察到约10μg/gDW样品的前导信号。UV-Vis分析显示最大肌酸峰约为220nm，与最大峰值为230nm的肌酐光谱兼容。使用HPLC技术，测得的肌酸与肌酐的比率极高，约为38，这导致了尿液中罕见肌酸晶体的发生。
