BACKGROUND Liver transplantation (LT) remains the definitive treatment for patients with acute and chronic end-stage liver disease, significantly improving survival and quality of life. Conventional liver function tests post LT, while routinely used, often lack sensitivity and may not detect graft injury promptly. Serum bile acids (SBAs), known for their role in hepatic function and enterohepatic circulation, have emerged as promising biomarkers due to their sensitivity to hepatocellular injury