[Ulcerative colitis: Does the modulation of gut microbiota induce long-lasting remission?].

Although the pathogenesis of ulcerative colitis (UC) remains elusive, substantial progress in understanding its development and progression has been achieved in the past decades, and novel effective treatment strategies have been developed. Changes in gut microbiota, environmental triggers, deregulation of immunological responses, and genetic predisposition have been identified as pathogenic key factors. There are several lines of clinical observations, which support a close connection of altered gut microbiota with the development and course of UC. Despite a plethora of microbiota alterations in UC, it is currently unclear whether the observed changes in inflammation are cause or effect of the altered microbiota state.Fecal microbiota transplantation (FMT) provides a novel, perhaps complementary, strategy to restore gut microbial diversity, bacterial richness, and microbial homeostasis in UC. FMT is an already established treatment option for recurrent Clostridioides difficile infection, and several case series and randomized controlled trials have described its use in UC. In this review, we evaluate recent efficacy and safety data on FMT for UC, discuss possible pitfalls and show possible areas of future development. Although FMT could become a promising treatment modality for UC, based on currently available data, FMT should be only performed in clinical trials as controlled studies focusing on long-term outcomes and safety are warranted.