BOSTON, Nov. 11, 2016 /PRNewswire/ -- A new scoring tool has been developed to assess the risk of developing a blood clot in the vein that brings blood from the intestines to the liver (portal vein) among people awaiting liver transplantation, according to research presented this week at The Liver Meeting® — held by the American Association for the Study of Liver Diseases. Portal vein thrombosis (PVT) in people with cirrhosis (scaring of the liver) can lead to worsening of liver disease, poorer outcomes and can potentially cause patients to be unable to receive a liver transplantation. Prevalence of PVT in patients undergoing, or under evaluation for, liver transplantation is five to 16 percent, and researchers from the Intermountain Medical Center in Murray, UT have developed a tool to assess the risk of patients with cirrhosis developing this complication. Dr. Charlton's team looked at the medical records of 621 patients on liver transplantation waiting list between December 1987 and May 2014. Patients were randomly divided into two groups: 70 percent were placed into group A (derivation group) and 30 percent into group B (validation group). The researchers looked at several risk factors in group A and found that presence of liver disease associated confusion, bacterial peritonitis, dilated veins in the esophagus or stomach, and a serum bilirubin level greater than 4.5 mg/dL showed association with developing PVT; using these factors a risk score was developed and tested on group B. A total of 63 patients developed PVT while awaiting liver transplantation. Using the risk factors in the study group, Dr. Charlton's team developed a PVT risk score with a maximum score of 5. A score of greater than three carried a hazard ratio of 15 for developing PVT.