Protein S for Portal Vein Thrombosis in Cirrhotic Patients Waiting for Liver Transplantation

Abstract

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.

Keywords: cirrhosis; liver transplantation; portal vein thrombus; protein S.

Figure 1

The Kaplan–Meier survival curve of the transplant recipients with or without PVT. The 1 year, 3 year and 5 year survival after transplantation for the patients with PVT were 90.3%, 71.0%, and 61.8%, compared with 86.1%, 76.2%, and 74.2% for the patients without PVT (p = 0.956).

Figure 2

The Kaplan–Meier survival curve of patients waiting for liver transplantation with protein S ≤ 60%. For all enlisted patients, the 6 month and 1 year overall survival for the patients with protein S ≤ 60% (n = 48) were 74.3% and 69.9%, compared with 88.1% (p = 0.008) and 84.1% (p = 0.012) for the patients with protein S > 60%, respectively.

Figure 3

The Kaplan–Meier survival curve of patients with liver transplantation and protein S ≤ 60%. For the patients with transplantation, the 6 month and 1 year overall survival for the patients with protein S ≤ 60% (n = 27) were 70.4% and 70.4%, compared with 89.4% (p = 0.006) and 84.8% (p = 0.047) for the patients with protein S > 60% (n = 136).