The human microbiome as a reservoir and modulator of antimicrobial resistance: emerging therapeutic implications

Background: The human microbiome represents a complex ecosystem that significantly influences antimicrobial resistance (AMR) patterns through multiple interconnected mechanisms. This review synthesizes current understanding of microbiome-pathogen interactions in the context of AMR development, persistence, and transmission. The gut microbiome serves as both a reservoir for resistance genes and a protective barrier against pathogen colonization through colonization resistance mechanisms. Dysbiosis induced by antibiotic therapy disrupts these protective functions, facilitating the emergence and spread of multidrug-resistant organisms. Recent advances in microbiome research have revealed novel therapeutic targets, including fecal microbiota transplantation, selective microbiome modulators, and precision antibiotic strategies. Understanding these complex interactions is crucial for developing next-generation antimicrobial stewardship programs and innovative therapeutic approaches. This review examines the bidirectional relationship between microbiome composition and AMR, explores emerging therapeutic interventions, and discusses future research directions that may transform our approach to infectious disease management in the era of rising antimicrobial resistance.