Intestinal microbiota and antibiotic resistance: Perspectives and solutions

The intestinal commensal microbiota provides a myriad of benefits to the healthy host, including colonisation resistance against pathogens. Perturbations of the intestinal microbiota (dysbiosis) may adversely affect the health status of an individual and prevent protection against colonisation. The whole range of antibiotic resistance genes (resistome) in a specific microbiota is found in pathogenic and non-pathogenic bacteria. The administration of antibiotics may cause dysbiosis, contributing to the loss of colonisation resistance followed by an increment of the resistome in the intestinal microbiota. Treatments to control the current increase of multi drug-resistant (MDR) bacteria are extremely limited. In this context, the administration of healthy faecal microbiota to restore colonisation resistance and displace MDR bacteria emerges as a promising therapeutic alternative. This brief review describes the role of the intestinal microbiota as a reservoir of MDR bacteria, the impact of different groups of antibiotics in the selection of MDR bacteria and crucially, the potential use of faecal microbiota transplantation using “healthy” or “MDR-free microbiota” to displace MDR bacteria and restore colonisation resistance