Prevalence of portal vein thrombosis in non-alcoholic fatty liver disease: a meta-analysis of observational studies.

Portal vein thrombosis (PVT) is a common complication of cirrhosis as a result of portal hypertension and modification in the hemostatic balance. Accumulating evidence now suggests that patients with non-alcoholic fatty liver disease (NAFLD), especially those with advanced forms, have an increased risk of PVT. Hence, we performed a meta-analysis of observational studies to estimate the overall prevalence of PVT in patients with NAFLD and its advanced forms compared with patients with advanced liver diseases from other etiologies. We systematically searched PubMed, Scopus and Web of Science databases from the inception date to December 30th 2022, using predefined keywords, to identify observational studies. Meta-analysis was performed using random-effects modeling. We included five observational studies for a total of 225,571 patients. Of these, 26,840 (11.9%) patients had NAFLD, whereas the PVT prevalence was 8.5% (n = 2,280). When compared with patients with advanced liver diseases from other etiologies, patients with NAFLD and its advanced forms had a higher risk of prevalent PVT (OR 1.34, 100% CI 1.07-1.67 p < 0,01). The between-study heterogeneity was substantial (I2 = 88%). This meta-analysis suggests that compared with patients with advanced liver diseases from other etiologies, patient with NAFLD and its advanced forms had a higher risk of prevalent PVT. Further research is required to understand the complex link between NAFLD/NASH and PVT development.

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.

Spur cells in liver cirrhosis are predictive of acute-on-chronic liver failure and liver-related mortality regardless of severe anaemia.

Chronic anaemia in advanced liver disease is a frequent finding. The aim was to explore the clinical impact of spur cell anaemia, a rare entity typically associated with end-stage of the disease. One-hundred and nineteen patients (73.9% males) with liver cirrhosis of any etiology were included. Patients with bone marrow diseases, nutrients deficiencies and hepatocellular carcinoma were excluded. In all patients, a blood sample was collected to check for the presence of spur cells on blood smear. A complete blood biochemical panel was recorded together with Child-Pugh (CP) score and Model for End-Stage Liver Disease (MELD) score. For each patients, clinically relevant events, such as acute-on-chronic liver failure (ACLF) and 1 year liver-related mortality, were registered. Patients were then grouped according to the percentage of spur cells at smear (> 5%, 1-5%, < 1%). Severe anaemia was defined as haemoglobin levels lower than 8 g/dL. 9.2% of subjects had > 5% spur cells, only 2 had evidence of haemolysis. In patients with > 5% spur cells, haemoglobin and albumin were lower compared with the other sub-group, while MELD score, CP score, International Normalized Ratio, ferritin, creatinine and unconjugated bilirubin were higher. Patients with more spur cells were more decompensated and developed more frequently ACLF. ACLF and liver-related mortality were significantly and independently associated with the presence of > 5% spur cells but not with baseline severe anaemia. Cirrhotic patients have a fairly high prevalence of spur cells, not always associated with severe haemolytic anaemia. The presence of spur red cells is per se associated with a worse prognosis and, therefore, should be always evaluated to prioritize patients for intensive management and eventually liver transplantation.

Chronic anaemia is a frequent finding in liver cirrhosis and spur cell anaemia has been shown to be an uncommon non-immune haemolytic disease typically related to advanced-liver disease. In our study, spur cell anaemia (spur cells >5%) was found in almost 10% of outpatient cirrhotics and was significantly related to more decompensated disease, higher incidence of ACLF and 1 year liver-related mortality. More importantly, the vast majority of patients with high percentage of spur cells did not have severe anaemia. Therefore, spur cells should be searched for in patients with advanced liver disease by a simple blood smear evaluation, even in the absence of significant anaemia, because of relevant prognostic impact and in order to prioritize patients to intensive management and possibly liver transplantation.