The characteristics of intestinal microbial communities may be affected by changes in the pathophysiology of patients with end-stage liver disease. Here, we focused on the characteristics of intestinal fecal microbial communities in post-liver transplantation (LT) patients in comparison with those in the same individuals pre-LT and in healthy individuals. The fecal microbial communities were analyzed via MiSeq-PE250 sequencing of the V4 region of 16S ribosomal RNA and were then compared between groups. We found that the gut microbiota of patients with severe liver disease who were awaiting LT was significantly different from that of healthy controls, as represented by the first principal component (p = 0.0066). Additionally, the second principal component represented a significant difference in the gut microbiota of patients between pre-LT and post-LT surgery (p = 0.03125). After LT, there was a significant decrease in the abundance of certain microbial species, such as Actinobacillus, Escherichia, and Shigella, and a significant increase in the abundance of other microbial species, such as Micromonosporaceae, Desulfobacterales, the Sarcina genus of Eubacteriaceae, and Akkermansia. Based on KEGG profiles, 15 functional modules were enriched and 21 functional modules were less represented in the post-LT samples compared with the pre-LT samples. Our study demonstrates that fecal microbial communities were significantly altered by LT.

Background and Aims: Biliary atresia is the most common cause of liver disease and liver transplantation in children. The accumulation of bile acids in hepatocytes and the stimulation of the intestinal microbiome can aggravate the disease progression. This study investigated changes in the composition of the gut microbiota and its metabolites in biliary atresia and the possible effects of these changes on disease progression.Methods: Stool samples of biliary atresia at different disease stages and matched control individuals were collected (early stage: 16 patients, 16 controls; later stage: 16 patients, 10 controls). Metagenomic sequencing was performed to evaluate the gut microbiota structure. Untargeted metabolomics was performed to detect and analyze the metabolites and bile acid composition.Results: A disturbed gut microbiota structure occurred in the early and later stages of biliary atresia. Klebsiella, Streptococcus, Veillonella, and Enterococcus have always been dominant. The abundance of V. atypica displayed significant changes between the early and later stages of biliary atresia. Combined with clinical indicators, Spearman’s analysis showed that Klebsiella and Veillonella atypica strongly correlated with liver enzymes. Enterococcus faecium had an enormously positive relationship with lithocholic acid derivatives. Metabolites involved in tryptophan metabolism were changed in the patients with biliary atresia, which had a significant association with stool V. atypica and blood total bilirubin (p < 0.05).Conclusions: The liver damage of biliary atresia was directly or indirectly exacerbated by the interaction of enriched Klebsiella (K. pneumoniae), Veillonella (V. atypica), and Enterococcus (E. faecium) with dysmetabolism of tryptophan and bile acid.

Aim: This study aimed to systematically characterize transplant rejection after immune checkpoint inhibitors (ICIs) initiation in solid organ transplant recipients (SOTRs).Methods: Data were extracted from the US FDA Adverse Event Reporting System (FAERS) database and case reports in the literature. Disproportionality analysis including information component and reported odds ratio (ROR) was performed to access potential risk signals.Results: A total of 168 patients with transplant rejection after ICIs usage were identified in the FAERS database, and 89 cases were identified in the literature review. ICIs were significantly associated with transplant rejection (ROR₀₂₅: 2.2). A strong risk signal was found for combination therapy with pembrolizumab and ipilimumab compared to monotherapy.Conclusion: Immune checkpoint inhibitors were significantly associated with transplant rejection in SOTRs.

Background-objectives: Liver transplantation (LT) and combined liver and kidney transplantation (CLKT) have been proposed as enzyme replacement therapies for methylmalonic aciduria (MMA). We aimed to synthesize the available evidence on their safety and efficacy. Medline, Embase and Cochrane library were searched to identify studies that reported post-LT/CLKT clinical outcomes of MMA from their inception to February 1, 2020. The pooled rate was calculated using random-effects model with Freeman-Tukey double arcsine transformation method. Thirty-two studies involving 109 patients were included. The pooled estimate rates were 99.9% (95% CI 95.3-100.0) for patient survival, 98.5% (95% CI 91.5-100.0) for graft survival after LT/CLKT. The combined incidence of biliary, vascular complications and rejection were 0.2% (95% CI 0.0-6.6), 7.7% (95% CI 0.1-22.1) and 18.4% (95% CI 4.6-36.3), respectively. The pooled estimate rates were 100.0% (95% CI 99.4-100.0) for metabolic eradication, 61.5% (95% CI: 33.4-87.0) for normalization of kidney function. Chronic kidney disease (CKD) remission is more promising after CLKT (70.3% VS 37.6% in LT group). The pooled estimate rates for neurodevelopmental status improvement and protein intake liberalization were 52.0% (95% CI 2.8-98.8) and 36.3% (95% CI 6.3-71.7), respectively. This first quantitative systematic review confirms favorable survival outcomes and partially improved disease-related complications in transplanted MMA patients, although some results should be interpreted with caution. Future studies with detailed description of long-term outcomes and consensus on neurodevelopmental evaluation method can help provide a more accurate picture.