From microbiome profiling to precision medicine: diagnostic and therapeutic potential in gastrointestinal disorders: current evidence, challenges, and future directions.

Gastrointestinal (GI) disorders, affecting millions globally (approximately 1.5 billion people with IBS alone), impose a significant healthcare burden and remain challenging to diagnose and manage. Current approaches are often invasive or symptom based, highlighting an urgent need for more precise and personalized strategies. The gut microbiome may offer novel diagnostic biomarkers and therapeutic targets, potentially transforming patient care. It supports GI and systemic health via metabolism, immune modulation, and neurochemical signaling. The dysbiosis of the gut microbiota contributes significantly to the pathogenesis of various GI disorders, including inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), colorectal cancer (CRC), and small intestinal bacterial overgrowth. This narrative review critically evaluates the diagnostic potential of microbiome profiling and its clinical applications in developing personalized therapeutic strategies. We examine cutting-edge techniques such as 16S rRNA sequencing, metagenomics, and metabolomics, and discuss how dietary modulation, precision probiotics, and fecal microbiota transplantation are being increasingly used to reshape gut microbial composition. However, it is critical to note that while microbiome alterations show consistent associations with GI diseases, current evidence remains largely observational and associative. To date, no microbiome-based test has achieved regulatory approval or clinical validation as a standalone diagnostic tool for IBD, IBS, or CRC, and therapeutic applications remain investigational with modest clinical benefits in select conditions. Additionally, we highlight the translational challenges of integrating microbiome-based diagnostics into mainstream clinical practice and propose future research imperatives. This review provides a balanced perspective on the promise and challenges of integrating microbiome-based approaches into clinical gastroenterology, while proposing actionable research priorities to guide future investigations toward clinically validated, patient-centered diagnostic, and therapeutic solutions.