Objective: The pathogenesis of irritable bowel syndrome is still not clearly understood. Brain-gut-microbiota disbalances might play an important role in irritable bowel syndrome (IBS) development. The aim of this scoping review was to summarize the latest scientific data regarding the role of microbiota in IBS pathogenesis.

Materials and Methods: PubMed was electronically searched for all observational and interventional studies, as well as systematic reviews and meta-analyses evaluating microbiota in IBS, within the interval of one year starting from March 2022 till March 2023.

Results: Compared to healthy controls, IBS subjects were observed to have an increase in Enterobacteriaceae, Ruminococcus, Clostridium, Dorea species and a decrease of Lactobacillus, Bifidobacterium, and Faecalibacterium species.

Conclusions: IBS with diarrhea predominance share similarities in the microbial profile with IBS patients with mixed bowel habits.