血清腹水白蛋白梯度在腹水鉴别诊断中的作用

Younas Muhammad, Sattar Abdus, Hashim Rizwan, Ijaz Aamir, Dilawar Muhammad, Manzoor Sayed Mohsin, Ali Asif, Khan Farooq Ahmad

J Ayub Med Coll Abbottabad. 2012 Jul-Dec;24(3-4):97-9.

BACKGROUND

The classification of ascites as 'exudative' and 'transudative' based on ascitic fluid total protein (AFTP) has been challenged in many clinical conditions like cardiac ascites, patients on prolonged diuretic therapy and malignant ascites because it had poor diagnostic efficacy. These drawbacks have led to the development of another approach to classify ascites, which is based on Serum-Ascites Albumin Gradient (SAAG) to differentiate ascitic fluid into two categories: SAAG > or = 11 g/L in ascites due to portal hypertension and SAAG < 11 g/L in ascites unrelated to portal hypertension. Objective of this study was to compare the diagnostic efficacy of serum/ascites fluid albumin gradient and ascitic fluid total protein in patients having ascites.

METHODS

This Cross-sectional comparative study was conducted in the Department of Chemical Pathology and Endocrinology, Armed Forces Institute of Pathology, Rawalpindi from 1st Jun 2007 to 30th May 2008. Ninety-three patients were included in the study by non probability convenience sampling. The patient grouped as: (Group I) 73 cases of liver cirrhosis, (Group II) 14 cases of hepatoma and 6 cases of tuberculous ascites. Ascitic fluid specimen and 3 ml blood were obtained for ascitic fluid estimation of ascitic fluid albumin, total proteins and serum albumin. Diagnostic efficacy of SAAG and AFTP was calculated by comparing the results with clinical, ultrasonographic, histopathological findings, ascitic fluid cell count/acid fast bacilli culture and other relevant investigations.

RESULTS

Seventy-three cases had liver cirrhosis (group I), 14 cases had hepatoma and 6 cases had tubercular ascites (group II). Age ranged 25-80 years with mean age 56 years. Diagnostic accuracy, Sensitivity, Specificity, Positive predictive value (PPV) and Negative predictive value (NPV) of SAAG were 96%, 97%, 95%, 98.6%, and 90% respectively, whereas those of AFTP were 56%, 53%,70%, 86%, and 29% respectively.

CONCLUSION

Differential diagnosis of ascites should be based on SAAG because diagnostic efficacy of SAAG was significantly higher than AFTP in work-up of ascites.

背景

基于腹水总蛋白（AFTP）将腹水分类为“渗出液”和“漏出液”，在许多临床情况下受到挑战，如心源性腹水、长期接受利尿治疗的患者以及恶性腹水，因为其诊断效能较差。这些缺点促使人们开发了另一种腹水分类方法，即基于血清-腹水白蛋白梯度（SAAG），将腹水分为两类：因门静脉高压导致的腹水，SAAG≥11g/L；与门静脉高压无关的腹水，SAAG＜11g/L。本研究的目的是比较血清/腹水白蛋白梯度和腹水总蛋白在腹水患者中的诊断效能。

方法

本横断面比较研究于2007年6月1日至2008年5月30日在拉瓦尔品第武装部队病理研究所化学病理学和内分泌科进行。通过非概率便利抽样纳入93例患者。患者分为：（I组）73例肝硬化患者，（II组）14例肝癌患者和6例结核性腹水患者。采集腹水标本和3ml血液，用于检测腹水白蛋白、总蛋白和血清白蛋白。通过将SAAG和AFTP的结果与临床、超声、组织病理学检查结果、腹水细胞计数/抗酸杆菌培养及其他相关检查进行比较，计算其诊断效能。

结果

73例为肝硬化患者（I组），14例为肝癌患者，6例为结核性腹水患者（II组）。年龄范围为25 - 80岁，平均年龄56岁。SAAG的诊断准确性、敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）分别为96%、97%、95%、98.6%和90%，而AFTP的相应值分别为56%、53%、70%、86%和29%。