Gut microbiota alterations and cirrhosis dysbiosis ratio in cirrhosis-associated portal vein thrombosis

Abstract Portal vein thrombosis (PVT) is a common, serious complication of cirrhosis. Although reduced hepatic reserve is a known risk factor for PVT, the role of dysbiosis remains unclear. This study investigated the effects of dysbiosis on PVT in patients with cirrhosis. Eighty-one patients with cirrhosis and seven healthy controls were included in the study. Gut microbiomes were analyzed using 16S rRNA from fecal samples, and dysbiosis was quantified using the cirrhosis dysbiosis ratio (CDR). The median age of participants was 70 years (52 males, 29 females). Hepatic reserve was classified as Child-Pugh A/B/C in 41/27/13 patients. Fourteen patients (17.2%) had PVT, linked to substantially reduced hepatic reserve. Gut microbiota analysis revealed distinct compositions and reduced diversity in patients with PVT(+). CDR values were substantially lower in patients with PVT(+), indicating severe dysbiosis. Logistic regression identified dysbiosis, reflected by low CDR values, as a considerable risk factor for PVT(+), regardless of the hepatic reserve. The proportion of PVT(+) cases was substantially higher in patients with low CDR values, even when stratified according to Child-Pugh grade. Gut microbiota in patients with PVT is altered independently of hepatic reserve, and CDR values could serve as a universal marker for PVT risk.