Alba D, Torres E, Vázquez J J
Departamento de Medicina Interna, Hospital Universitario, La Paz, Madrid.
An Med Interna. 1995 Aug;12(8):404-7.
The serum-ascites albumin (SAA) gradient has been defined as the serum albumin concentration minus the ascitic fluid albumin concentration. The SAA gradient is superior to the exudate-transudate concept to classify ascites, being a exact portal hypertension (PH) marker. An elevated SAA gradient (1.1 g/L or greater) correlates with PH, whereas a low gradient indicates no PH. The SAA gradient correlates well with PH in cirrhotic patients. It is also of particular utility to differentiate between congestive heart failure and malignant ascites without liver metastases (both of them with elevated ascites fluid proteins -AFP-). However, a low SAA gradient do not differentiate between tuberculous and malignant ascites. Consequently, there are still need for tests a cytology, culture for mycobacteria or ascites fluid polymorphonuclear cell count in some cases. The level of AFP, apart from the exudate-transudate concept, has some value for certain cases (a low level of AFP implicates a high risk of spontaneous bacterial peritonitis). The SAA gradient should replace the AFP concentration as the initial test to classify ascites.
血清-腹水白蛋白（SAA）梯度定义为血清白蛋白浓度减去腹水白蛋白浓度。SAA梯度在腹水分类方面优于渗出液-漏出液概念，是门静脉高压（PH）的准确标志物。升高的SAA梯度（1.1g/L或更高）与PH相关，而低梯度表明无PH。SAA梯度在肝硬化患者中与PH密切相关。它在区分充血性心力衰竭和无肝转移的恶性腹水（两者腹水蛋白-AFP-均升高）方面也特别有用。然而，低SAA梯度无法区分结核性和恶性腹水。因此，在某些情况下仍需要进行细胞学检查、分枝杆菌培养或腹水多形核细胞计数。除渗出液-漏出液概念外，AFP水平在某些情况下有一定价值（低水平AFP提示自发性细菌性腹膜炎的高风险）。SAA梯度应取代AFP浓度作为腹水分类的初始检查。
