Portal vein thrombosis (PVT) is a frequent and severe complication in patients with cirrhosis; however, the pathophysiology of PVT needs to be better clarified. There are few significant predictive factors in clinical practice, and the impact of PVT on cirrhosis progression and its complications, such as gastrointestinal bleeding, hepatic encephalopathy, and hepatorenal syndrome, remains uncertain. In recent years, the understanding of the mechanisms of PVT has become more profound with the publication of related literature. Therefore, in this review, we aim to summarize the advanced progress in the epidemiology, hazards, risk factors, diagnosis and classification, and treatment of PVT to provide insight into clinical management.

Introduction To review existing studies and perform a meta-analysis to clarify the value of serum amino acid levels in patients with cirrhosis as a potential biomarker for predicting cirrhosis. Methods Literature retrieved from 8 databases up to 31 December 2022, and were screened according to inclusion criteria. The Newcastle-Ottawa Quality Assessment Scale (NOS) was used to assess the risk of bias in the included literature. A random effects model for amino acid concentrations in meta-analysis was used to calculate mean differences (MD) and 95% confidence intervals (95% CI). I2 statistic was used to measure study heterogeneity. This study was registered with PROSPERO. Results A total of 1380 records were retrieved and 19 studies with 2073 individuals (831 in the cirrhosis group and 1242 in the healthy control group) were included after screening. The quality of the included studies was generally high. Qualitative analysis of 19 studies including 23 amino acids. Meta-analysis of 5 studies showed that 6 amino acids were significantly increased in the cirrhotic group: Tyr, Met, Orn, Thr, Cit, and Trp, and 2 amino acids were significantly decreased: Arg and Val. At subgroup analysis, the combined results of Arg in serum of patients with hepatitis B cirrhosis were not statistically heterogeneity, and the remaining results in subgroup were similar to the primary results. Conclusions Alterations in serum amino acid profile were associated with cirrhosis. Some specific amino acids (Tyr, Met, Orn, Thr, Cit, Trp, Arg, and Val) may serve as biomarkers to predict cirrhosis.