Multidrug-Resistant Organisms (MDROs) are microorganisms, most commonly bacteria, that have developed resistance to multiple antimicrobial drugs. This means that some antibiotics normally used to treat bacterial infections may no longer be effective. MDROs can cause infections in different parts of the body, including the bloodstream, lungs, urinary tract, skin, wounds, and surgical sites.

MDROs can develop when bacteria adapt to antimicrobial treatment or acquire resistance genes from other bacteria. The use of antibiotics, particularly when they are unnecessary or used for longer than needed, can increase the selection of resistant bacteria. MDROs can spread through direct contact or through contaminated hands, surfaces, medical equipment, and devices. While they are often associated with healthcare settings, some MDROs can also spread in community settings.

An MDRO can be present on or in the body without causing illness, which is known as colonization. When the organism causes illness, it is considered an infection. Common examples include methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and extended-spectrum beta-lactamase (ESBL)-producing bacteria. MDRO infections can be difficult to treat because the organisms may be resistant to several commonly used antibiotics, so treatment depends on which antimicrobial drugs the organism remains susceptible to.

Disclaimer: This information is for general educational purposes only and does not replace professional medical advice, diagnosis, or treatment. Consult a qualified healthcare professional for advice about any health concern.