Authors' reply to letter: He who controls Clostridia and Bacteroidia controls the gut microbiome: The concept of targeted probiotics to restore the balance of keystone taxa in irritable bowel syndrome.

A recent study published in Neurogastroenterology & Motility compared the effectiveness of the Lab4 probiotic preparation to a placebo in improving symptoms of irritable bowel syndrome (IBS) in female patients. The authors of the study responded to a letter from Sitkin and Pokrotnieks, agreeing with their argument that probiotics may restore certain "keystone taxa" within the gut microbiome, even if overall composition or diversity metrics do not change significantly. The authors analyzed stool microbiome profiles from multiple trials and identified five genera that consistently played a role in microbiome structure and function. They also emphasized the importance of studying functional changes in the gut microbiome and exploring other gut microbial metabolite systems associated with IBS. The response concludes by acknowledging the challenges and opportunities in targeting the gut microbiome in IBS. [Extracted from the article]