MDROs

MDROs, or multidrug-resistant organisms, are infectious agents that resist multiple antimicrobial drugs, limiting treatment options. In healthcare, the term typically refers to bacteria such as MRSA (methicillin-resistant Staphylococcus aureus), VRE (vancomycin-resistant Enterococcus), ESBL-producing Enterobacterales, and carbapenem-resistant Enterobacterales (CRE). Other notable MDROs include Pseudomonas aeruginosa, Acinetobacter species, and resistant strains of Mycobacterium tuberculosis and Candida auris.

Resistance arises through genetic mutations and acquisition of resistance genes, often via plasmids. Antibiotic use and inadequate infection control create selective pressure that favors resistant strains. MDROs spread in healthcare settings through hands, contaminated surfaces, medical devices, and close contact. Colonization, carrying the organism without symptoms, can precede infection.

Impact and detection: MDRO infections are harder to treat and associated with higher mortality, longer hospital stays, and increased costs. Detection relies on culture and antimicrobial susceptibility testing, with rapid molecular tests used in some settings to speed up decisions.

Prevention and control: antimicrobial stewardship to minimize unnecessary antibiotic use; strict hand hygiene; contact precautions for patients known or suspected to harbor MDROs; thorough environmental cleaning; surveillance and, when needed, patient isolation or cohorting.

Treatment considerations: therapy is tailored to the organism and its susceptibilities. Options may include combinations or newer agents, while some MDROs have very limited choices. Early involvement of infectious diseases specialists and prudent antibiotic use help preserve remaining options.

Public health perspective: MDROs present a global challenge, with regional differences in prevalence. Effective control requires surveillance, reporting, infection control, vaccination where available, and ongoing development of new antimicrobials and stewardship strategies.