A 45-year-old man with cirrhosis due to NASH develops new-onset ascites. Diagnostic paracentesis shows: serum-ascites albumin gradient (SAAG) = 1.5 g/dL, ascitic fluid protein 1.8 g/dL, glucose 90 mg/dL, LDH 80 U/L. What does the SAAG value indicate?

• A Exudative ascites due to peritoneal tuberculosis
• B Malignant ascites due to peritoneal carcinomatosis
• C Nephrotic syndrome-related ascites
• D Ascites due to portal hypertension (hydrostatic cause) ✓

Explanation

The serum-ascites albumin gradient (SAAG) = serum albumin − ascitic fluid albumin. A SAAG ≥ 1.1 g/dL indicates portal hypertension as the cause of ascites (hydrostatic mechanism), with high sensitivity and specificity (>95%). Cirrhosis, congestive heart failure, Budd-Chiari syndrome, and portal vein thrombosis all produce SAAG ≥ 1.1. Exudative causes (tuberculosis, malignancy, pancreatitis) produce SAAG < 1.1 g/dL.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.