Akkermansia muciniphila in the small intestine improves liver fibrosis in a murine liver cirrhosis model.

Recent evidence indicates that liver cirrhosis (LC) is a reversible condition, but there is no established intervention against liver fibrosis. Although the gut microbiota is considered involved in the pathogenesis of LC, the underlying mechanisms remain unclear. Although the antibiotic, rifaximin (RFX), is effective for hepatic encephalopathy (HE) with LC, the impact of RFX on intestinal bacteria is unknown. We investigated the bacterial compositions along the GI tract under RFX treatment using a murine LC model. RFX improved liver fibrosis and hyperammonemia and altered the bacterial composition in the small intestine. The efficacy of RFX was associated with increases in specific bacterial genera, including Akkermansia. Administration of a commensal strain of Akkermansia muciniphila improved liver fibrosis and hyperammonemia with changing bacterial composition in the small intestine. This study proposed a new concept "small intestine-liver axis" in the pathophysiology of LC and oral A. muciniphila administration is a promising microbial intervention.

A case report of limitation of transcatheter hepatic arterial embolization for hereditary hemorrhagic telangiectasia type 2 with pulmonary arterial hypertension.

INTRODUCTION AND IMPORTANCE: Arteriovenous malformations (AVMs) in the liver caused by hereditary hemorrhagic telangiectasia (HHT) influence pulmonary artery hypertension (PAH). Liver transplantation (LT) is the most common treatment for HHT-induced hepatic AVMs. However, LT is contraindicated for patients with severe PAH. There is controversy regarding the ideal therapeutic approach for HHT with PAH and hepatic AVMs. CASE PRESENTATION: We present the case of a 48-year-old female with PAH and HHT. After the initiation of PAH-targeted drugs, we considered that the PAH was mainly caused by high cardiac output secondary to multiple diffuse AVMs in the liver. LT was contraindicated due to high mean pulmonary arterial pressure (mPAP), and we opted to perform transcatheter embolization as an alternative treatment for the AVM. Multiple-stage embolization sessions did not effectively improve the shunt in the liver or the pulmonary hemodynamics. The patient died of an uncontrolled gastrointestinal hemorrhage. CLINICAL DISCUSSION: LT was considered in our case; it was contraindicated because of pulmonary hypertension that was in line with the model for end-stage liver disease exception criteria. Repeated embolization did not reduce the liver shunt or improve pulmonary hemodynamics, possibly due to the diffuse distribution of AVMs in the liver and the rapid development of new collateral vessels with each embolization. Recently, pulmonary vascular resistance (PVR) has been proposed as a more appropriate index for stratifying perioperative risk. CONCLUSION: Based on previous reports and our experience, rapid decision-making regarding LT may be needed based on mPAP and PVR after the initiation of PAH-targeted drugs.

Extent of disease affects the usefulness of fecal biomarkers in ulcerative colitis.

BACKGROUND: Fecal biomarkers are considered to be useful surrogate markers for endoscopic activity. Given the mechanisms of fecal biomarkers, we hypothesized that the extent of ulcerative colitis (UC; pancolitis, left-sided colitis, and proctitis) could affect the usefulness of fecal biomarkers for assessing endoscopic and clinical disease activity; however, few studies have evaluated the utility of fecal biomarkers in the disease extent of UC. METHODS: Fecal calprotectin, a fecal immunochemical test for hemoglobin, and fecal lactoferrin were used as fecal biomarkers. UC patients, who underwent colonoscopy within 30 days of the fecal biomarker test, participated in this observational study. Clinical and endoscopic disease activity was assessed using the Lichtiger Index and Mayo endoscopic subscore (MES), respectively. RESULTS: A total of 162 colonoscopies were performed on 133 UC patients. A correlation analysis between each biomarker and the MES for each disease-extent subgroup showed a decreased correlation in the proctitis compared with the other groups. With the exception of proctitis, it was possible to distinguish between MES 0 and MES ≥ 1 with high area-under-the-curve values for fecal calprotectin and fecal lactoferrin. The fecal immunochemical test for hemoglobin was superior at discriminating MES 0 for proctitis. CONCLUSIONS: For the practical application of fecal biomarkers for UC patients, it is necessary to consider disease extent before use. In particular, patients with proctitis exhibit a low correlation between stool biomarkers and endoscopic findings. The usefulness of these biomarkers for endoscopic remission is reduced, except for the fecal immunochemical test for hemoglobin.