Microbiome Composition Recovery after Liver Transplantation Correlates with Initial Liver Disease Severity and Antibiotics Treatment

Liver transplantation (LT) is crucial for end-stage liver disease, but it is linked to infection risks. Pathobionts, microorganisms potentially harmful under specific conditions, can cause complications post-transplant. Monitoring such pathogens in fecal samples can be challenging and therefore remains underexplored post-LT. This study aimed to analyze the gut microbiome before and after LT, tracking pathobionts and correlating clinical data.The study involved 17 liver transplant recipients, 17 healthy relatives (spouses), and 13 donors. Gut samples collected pre- and post-transplantation underwent bacterial and fungal profiling through DNA sequencing. Quantitative PCR was used to assess microbial load. Statistical analyses included alpha and beta diversity measures, differential abundance analysis, and correlation tests between microbiome and clinical parameters.Microbiome analysis revealed dynamic changes in diversity post-transplant. Notably, high-severity patients showed persistent and greater dysbiosis during the first months post-LT compared to low-severity patients, partly due to an antibiotic treatment pre-LT. The analysis identified a higher proportion of pathogens such as Escherichia coli/Shigella flexneri in high-severity cases post-transplant. Furthermore, butyrate producers including Roseburia intestinalis, Anaerostipes hadrus and Eubacterium coprostanoligenes were positively correlated with levels of albumin.This study offers valuable insights into post-LT microbiome changes, shedding light on the need for tailored prophylactic treatment post-LT.