Hepatic encephalopathy (HE) has various clinical symptoms, and its etiology and pathogenesis have not been fully understood. Recent studies have shown that the composition of intestinal flora is associated with the changes in the central nervous system in patients with HE. With reference to recent studies in China and foreign countries, this article analyzes and summarizes the regulatory mechanism of intestinal flora on HE through the liver-brain axis from the perspectives of microbiology, nervous system, and immunology, and it is pointed out that in-depth studies on the mechanism of action of intestinal flora are needed for the treatment of HE and can provide a clear basis for clinical diagnosis and treatment.

Objective To evaluate the degree of liver injury and liver fibrosis in patients in the immune-tolerant phase of chronic HBV infection, and to provide a basis for judging the condition of patients in the immune-tolerant phase. Methods A total of 300 patients with HBV DNA ≥10 7 IU/mL, alanine aminotransferase (ALT) ≤40 U/L, and complete data who were treated in The Third People's Hospital of Kunming from January 2015 to December 2019 were enrolled as subjects, and related data were collected, including age, sex, duration of HBV infection, blood biochemistry, hepatitis B surface antigen (HBsAg) level, and HBV DNA. Liver pathological examination was performed for all patients, and the patients were divided into G < 2 and G ≥2 groups according to inflammation grade and S < 2 and S ≥2 groups according to the degree of fibrosis. The t -test was used for comparison of continuous data between two groups, and univariate and multivariate unconditional logistic regression analyses were used to investigate the influencing factors for G ≥2 liver inflammation and S ≥2 liver fibrosis. Results Among the 300 patients, 213 (71%) had G ≥2 liver inflammation and 120 (40%) had S ≥2 liver fibrosis, with a baseline age of 26.06±9.01 years; male patients accounted for 48%, and the duration of infection was 5.62±5.09 years. The univariate analysis showed that there were significant differences between the G < 2 and G ≥2 groups in ALT, alkaline phosphatase (ALP), albumin (Alb), platelet count (PLT), diameter of the portal vein, and spleen thickness ( t =-26.677, -11.612, 2.149, 5.410, -6.092, and -2.911, all P < 0.05), and there were significant differences between the S < 2 and S ≥2 groups in duration of infection, ALT, ALP, Alb, HBV DNA, PLT, diameter of the portal vein, and spleen thickness ( t =-6.320, -6.694, -7.880, 2.349, 4.552, 19.160, -5.782, and -5.622, all P < 0.05). The multivariate analysis showed that ALT (odds ratio [ OR ]=10.270, 95% confidence interval [ CI ]: 2.212-47.672, P =0.003) and ALP ( OR =1.097, 95% CI : 1.013-1.188, P =0.023) were independent risk factors for G ≥2 liver inflammation in patients in the immune-tolerant phase, and ALP ( OR =1.034, 95% CI : 1.015-1.054, P < 0.001), PLT ( OR =0.913, 95% CI : 0.886-0.938, P < 0.001), HBV DNA ( OR =0.198, 95% CI : 0.062-0.636, P =0.007), and duration of infection ( OR =1.176, 95% CI : 1.033-1.340, P =0.015) were independent influencing factors for S ≥2 liver fibrosis in patients in the immune-tolerant phase. Conclusion Most patients in the immune-tolerant phase have significant liver histological changes. ALT and ALP are the influencing factors for significant liver inflammation, and ALP, HBV-DNA, PLT, and infection time are the influencing factors for significant liver fibrosis in patients in the immune-tolerant phase.