Bacterial infections as a risk factor for non-neoplastic portal vein thrombosis development in cirrhotic patients

Background: Portal vein thrombosis (PVT) and sepsis are common complications in patients with liver cirrhosis. Factors that lead to PVT are not completely understood. This study aimed to investigate the possible association between bacterial infections and the development of PVT in cirrhotic patients. Patients and Methods: 202 consecutive cirrhotic patients without previous infections, followed at the Liver Unit in Verona Hospital, were enrolled from 2017 to 2021 (median follow-up 3.3 years). During the follow-up period, PVT was diagnosed by ultrasound, CT and/or MRI, and episodes of bacterial infections requiring hospitalization were recorded. Malignant PVT was an exclusion criterion. Results: Of the 202 patients enrolled (68.3 % males, mean age 63.8 +/- 11 years), 22 (10.8 %) developed PVT during the follow up. In patients with PVT, the prevalence of previous bacterial infections was significantly higher compared to patients without PVT (63.6% vs 31.1 %; p = 0.02). Cox regression analysis revealed that a history of bacterial infection was the only variable that demonstrated a significant association with the risk of de novo PVT occurrence (HR 4.04, 95 % CI: 1.68-9.65). Conclusion: in patients with liver cirrhosis bacterial infections are a predisposing factor for the following development of PVT. Further studies are needed to confirm this evidence.