The Correlation Between Serum Serotonin Level and Grade of Esophageal Varices in Patients with Liver Cirrhosis

Background: Esophageal Varices (EV) are a major complication of hepatic cirrhosis due to portal hypertension. Endoscopic screening, while effective, is invasive and resource-intensive. Identifying reliable noninvasive markers is therefore crucial. Aim: To evaluate the role of serum serotonin levels as a noninvasive marker for the diagnosis and grading of esophageal varices in cirrhotic patients. Methods: This cross-sectional comparative study included 140 subjects divided into three groups: Group A (60 cirrhotic patients with esophageal varices, subdivided by grade I–III), Group B (40 cirrhotic patients without EV), and Group C (40 non-hepatic controls). All underwent clinical, laboratory, imaging, and endoscopic evaluation. Serum serotonin was measured using ELISA (Bioassay Technology Laboratory, Shanghai, China). Results: Serum serotonin levels were significantly higher in cirrhotic patients compared to controls (91.84 ± 14.39 ng/ml in Group A, 59.97 ± 9.78 ng/ml in Group B vs. 30.03 ± 5.64 ng/ml in Group C, p<0.001). No significant differences were observed between different grades of EV. Serotonin levels correlated positively with Child–Pugh class (p<0.001). Receiver Operating Characteristic (ROC) analysis showed that serotonin at a cutoff of 0.81 ng/mL predicted EV with 98% sensitivity and 83% specificity, while a cutoff of 0.59 ng/mL predicted cirrhosis with 99% sensitivity and 60% specificity. Conclusion: Serum serotonin is significantly elevated in cirrhotic patients, particularly those with esophageal varices, and correlates with disease severity. While it cannot differentiate variceal grades, serotonin demonstrates high diagnostic accuracy as a noninvasive screening marker for cirrhosis and EV, potentially reducing the need for unnecessary endoscopy. Keywords: Child-Pugh Classification, Cirrhosis, Esophageal Varices, Portal Hypertension, Serotonin.