Predictive Value of Non-Invasive Blood Ammonia Level for the Presence of Oesophageal Varices in Egyptian Patients With Liver Cirrhosis

Abstract

AIM: Although recent guidelines recommend screening of cirrhotic patients by upper endoscopy for oesophageal varices prediction, Non-invasive parameters are needed due to high endoscopy cost and burden on endoscopic units particularly in poor countries. The aim of this study is to evaluate the accuracy of using ammonia blood level as potential non-invasive predictor of oesophageal varices in cirrhotic patients. Methods: This prospective study was conducted on 150 Egyptian participants. Patients were categorized as group I which included 100 with oesophageal varices and group II included 30 patients without varices. There were 20 healthy control participants served as a control group (group III). All patients underwent for full clinical and laboratory workup, abdominal ultrasound and upper gastrointestinal endoscopy. Venous ammonia blood levels were calculated for all the contributors of this study. Results: The mean ammonia level was higher in group I (88.29±42.82 µmol/L) than in group II (82.77±49.76 µmol/L) with no statistical significant difference between the two groups (p=0.34). Ammonia level in group III was 73.37±30.36 µmol/L with no statistical significant difference with the other groups (p>0.05). In group I; ammonia level is positively correlated with the splenic vein diameter with r = 0.22 (p=0.026) but did not correlate with the grade of oesophageal varices r =0.031 (p-value=0.762). In multivariate analysis; ammonia combined with platelets, Age, PT and PC shared in a significant prediction model (I) for esophageal varices grading (p=0.002). Prediction model (II) including portal and splenic veins diameters and the liver size was developed (p=0.016). Conclusion: Non-invasive means could be used to monitor cirrhotic patients and consider treatment. Ammonia level can not be used alone but its use within a significant prediction model can help restricting the use of endoscopic screening in patients with a high probability of esophageal varices.