Intestinal Dysbiosis and Alterations of Cross-Feeder Bacteria in the Development of Antimicrobial Resistance

Intestinal dysbiosis represents a significant disruption of the gut microbiota and is closely associated with the development of antibiotic resistance. This study aims to evaluate the role of alterations in cross-feeder bacteria in this process. A retrospective analysis was conducted on six dysbiosis tests (GA-map® Dysbiosis Test) performed over the past six months at the Intermedica Medical Center Laboratory. The study included six intestinal microbiota profiles obtained from patients routinely referred for microbiota evaluation at the Intermedica Medical Center Laboratory. The profiles were analyzed retrospectively, without additional study-specific inclusion criteria. Changes in microbiota composition and the presence of key metabolic bacteria were analyzed. A reduction in bacterial diversity and alterations in the commensal flora were observed in most cases. The most significant finding was a decrease in cross-feeder bacteria, which play a crucial role in the production of short-chain fatty acids (SCFAs). This reduction was associated with an increase in opportunistic microorganisms. The observed patterns suggest that antibiotic use creates selective pressure that promotes resistance through mechanisms such as horizontal gene transfer and biofilm formation. Intestinal dysbiosis, particularly the disruption of cross-feeder bacteria, plays a key role in the development of antibiotic resistance. Monitoring the gut microbiota and implementing targeted therapeutic interventions—including probiotics, prebiotics, and the rational use of antibiotics—are essential for maintaining intestinal homeostasis and preventing the spread of antimicrobial resistance.