Protein S for portal vein thrombosis in cirrhotic patients waiting for liver transplantation

Portal vein thrombus (PVT) is a challenge in liver transplantation. How PVT develops in cirrhotic patients who already have coagulopathy is unclear. This study aimed to investigate possible contributing factors to PVT in cirrhotic patients. A total of 349 cirrhotic patients who waited liver transplantation were included in this study and 48 of them had PVT. For all the patients, the mean age was 53.5 ± 9.0 year old, and 75.9% of the patients were male. There were 233 (66.8%) patients who had either hepatitis B or C. The mean Model For End-Stage Liver Disease (MELD) score was 16.4 ± 7.5. Eighteen of 48 patients with PVT and 145 of 301 patients without PVT received liver transplantation. Multivariate analysis showed that low protein S level (hazard ratio = 2.46, p = 0.017) was the only independent risk factor for PVT development. Protein S deficiency also demonstrated prognostic value on short-term survival, not only for cirrhotic patients awaiting liver transplantation (69.9% versus 84.1% at 1 year survival, p = 0.012), but also for the patients having liver transplantation (70.4% versus 84.8% at 1 year survival, p = 0.047). In conclusion, protein S level was an independent risk factor for PVT development in decompensated cirrhotic patients, and protein S deficiency was also a prognostic factor for the patients waiting for liver transplantation.