Teneva Bilyana H
Gastroenterology Unit, II Department of Internal Medicine, Medical University, Plovdiv, Bulgaria.
Folia Med (Plovdiv). 2012 Oct-Dec;54(4):5-13. doi: 10.2478/v10153-011-0100-z.
In liver cirrhosis patients awaiting liver transplantation, it is prognostically equally important to assess the renal function before and after transplantation. This is evidenced by the inclusion of serum creatinine in the Model for End-Stage Liver Disease (MELD) score. Most of the causes of renal failure in liver cirrhosis are functional, the acute kidney damage including prerenal azotemia, acute tubular necrosis and hepatorenal syndrome. A major index of the renal function, the glomerular filtration rate (GFR) is determined in a specific way in patients with liver cirrhosis. Clinically, serum creatinine is considered the best indicator of kidney function, although it is rather unreliable when it comes to early assessment of renal dysfunction. Most of the patients with liver cirrhosis have several concomitant conditions, which are the reason for the false low creatinine levels, even in the presence of moderate to severe kidney damage. This also holds for the creatinine clearance and creatinine-based estimation equations for assessment of the glomerular filtration rate (the Cockroft-Gault and MDRD formulas), which overestimate the real glomerular filtration. Clearance of exogenous markers is considered a gold standard, but the methods for their determination are rather costly and hard to apply. Alternative serum markers (e.g., cystatin C) have been used, but they should be better studied in cases of liver cirrhosis assessment.
在等待肝移植的肝硬化患者中，移植前后评估肾功能在预后方面同样重要。终末期肝病模型（MELD）评分纳入血清肌酐就证明了这一点。肝硬化患者肾衰竭的大多数病因是功能性的，急性肾损伤包括肾前性氮质血症、急性肾小管坏死和肝肾综合征。在肝硬化患者中，肾小球滤过率（GFR）这一肾功能的主要指标是以特定方式测定的。临床上，血清肌酐被认为是肾功能的最佳指标，尽管在早期评估肾功能不全时它相当不可靠。大多数肝硬化患者有多种合并症，这就是即使存在中度至重度肾损伤，肌酐水平仍会假性降低的原因。这也适用于用于评估肾小球滤过率的肌酐清除率和基于肌酐的估算方程（Cockcroft-Gault公式和MDRD公式），它们会高估实际的肾小球滤过率。外源性标志物清除率被视为金标准，但其测定方法成本高昂且难以应用。已经使用了替代血清标志物（如胱抑素C），但在肝硬化评估病例中应对其进行更深入的研究。
