Diagnostic accuracy of serum - ascites albumin gradient (SAAG) for detection of esophageal varices in patients with liver cirrhosis

Abstract

Introduction: Identifying patients with compensated cirrhosis who are at risk of developing esophageal varices (EVs) is crucial for effective management. The Serum Ascites Albumin Gradient (SAAG) is a non-invasive laboratory tool that can predict the presence of EVs in cirrhotic patients, with a cutoff value of >1.4 g/dL indicating the need for clinical attention. SAAG can potentially reduce the need for repeated upper endoscopies.

Objective: To evaluate the diagnostic accuracy of SAAG in diagnosing esophageal varices in patients with cirrhosis, using endoscopy as the gold standard.

Materials and Methods: This cross-sectional study was conducted between April 2023 and October 2023 at the North Medical Ward, Department of Medicine, Mayo Hospital, Lahore. A total of 270 patients with cirrhosis and ascites (age 20-60 years) from both the genders were enrolled using non-probability consecutive sampling. 5cc blood and ascitic fluid samples were collected and sent to the hospital's laboratory for SAAG assessment. Patients underwent endoscopy to determine the presence of EVs, with varices considered present if the esophageal veins measured >5 mm in diameter.

Results: The diagnostic performance of SAAG in detecting EVs was evaluated, with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) calculated. The results showed that SAAG had a sensitivity of 87.5%, specificity of 59.86%, PPV of 66.27%, and NPV of 84.16%.

Conclusion: SAAG is a non-invasive, cost-effective tool with high sensitivity but low specificity for diagnosing esophageal varices in cirrhotic patients. Therefore, while SAAG can help reduce the frequency of endoscopy, it should be used in conjunction with other diagnostic methods for more accurate patient management.