LAUSR

Abstract The human microbiome plays a critical role in health and disease. The microbiota of the human body undergoes disruptions in critical illness, in part due to alterations in physiology but also as the result of medical interventions, most notably antimicrobial drug administration. These alterations may lead to a significant dysbiosis, with increased risks of multi-drug-resistant organism-based secondary infections, Clostridioides difficile promotion, and other infection-related complications. Antimicrobial stewardship is a process that seeks to optimize antimicrobial drug prescription, with recent evidence emphasizing shorter courses of therapy, earlier transitions from empiric to pathogen-specific regimens, and enhanced diagnostic testing. Through a combination of prudent stewardship and wise use of diagnostic testing, clinicians can improve outcomes, reduce the risk of antimicrobial resistance, and help improve the integrity of the microbiome.