Multidrug-resistant organisms (MDROs) are bacteria that are not able be treated with certain types of antibiotics and require treatment with other medicines that may be less effective, more toxic, and more expensive. There are several types of MDROs may be found in healthcare facilities, including carbapenem-resistant Enterobacteriaceae (CRE), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate or vancomycin resistant Staphylococcus aureus (VISA/VRSA), and vancomycin-resistant Enterococci (VRE). It is possible to carry a MDRO in or on your body but not show any symptoms; this is called colonization. Symptoms of an active infection will depend on the type of organism, the site of infection, and individual risk factors.
Acinetobacter baumannii is a type of bacteria commonly found in soil and water that can become resistant to many commonly prescribed antibiotics. Infections caused by these bacteria rarely occur outside of healthcare settings and can cause a variety of diseases, ranging from pneumonia to serious blood or wound infections.
Enterobacteriaceae is a family of bacteria that include E. coli, Enterobacter, Klebsiella, Salmonella, and several other common types of bacteria. If these bacteria develop resistance to carbapenems, a class of antibiotics, they become carbapenem-resistant Enterobacteriaceae (CRE). CRE are very difficult to treat because they are usually resistant to almost all available antibiotics. CRE may cause a variety of infections ranging from gastrointestinal illness to pneumonia to invasive infections of the bloodstream or other body organs.
Methicillin-resistant Staphylococcus aureus (MRSA) is a type of Staphylococcus (staph) bacteria that is resistant to certain antibiotics called beta-lactams. These antibiotics include methicillin and other more common antibiotics such as oxacillin, penicillin, and amoxicillin. In the community, most MRSA infections are skin infections and may appear as red boils or pimples. More severe or potentially life-threatening MRSA infections occur most frequently among patients in healthcare settings and may initially present as symptoms such as fever and pain at the site of infection. While 25% to 30% of people are colonized in the nose with staph, less than 2% are colonized with MRSA. (citation)
Like MRSA, Vancomycin-intermediate Staphylococcus aureus (VISA) and Vancomycin-resistant Staphylococcus aureus (VRSA) are types of staph bacteria that are resistant (or have intermediate resistance) to certain antibiotics. Because of their resistance to antibiotics, VISA/VRSA infections can be more difficult to treat. VISA/VRSA infections may affect the skin or may get into the bloodstream, causing a more serious type of infection.
Enterococci are a type of bacteria found naturally in the environment, as well as in the human intestines and the female genital tract. When these bacteria develop resistance to vancomycin, they become Vancomycin-resistant Enterococci (VRE). Most VRE infections occur in people who are hospitalized.
Factors that increase a patient’s risk of developing an infection caused by a MDRO may vary depending on the type of organism. In general, risk factors include underlying health conditions, a weakened immune system, prolonged hospitalization, exposure to an invasive device such as a ventilator or catheter, recent surgery, and frequent antibiotic use.
MDROs are transmitted via direct contact with an infected person or indirect contact with contaminated objects/surfaces in the environment of an infected person. It is important that both the patient and the healthcare providers take the appropriate steps to help prevent an infection caused by a MDRO.
Estimated burden of MDROs in healthcare facilities in the United States:
In January 2013, the Centers for Medicare and Medicaid Services (CMS) will begin requiring acute care hospitals participating in their Inpatient Prospective Payment System (IPPS) to report MRSA bacteremia facility-wide using the National Healthcare Safety Network (NHSN). These data will be made publicly available on Hospital Compare.
To prevent the transmission of MRSA, doctors, nurses, and other healthcare providers can do the following things:
CDC MRSA Prevention Collaborative Toolkit - contains background on epidemiology of MRSA as well as core and supplemental prevention strategies
General Resources – MDROs and Drug Resistance
Antibiotic stewardship webpage
Drug Resistance and Antibiotic Stewardship fact sheet
NHSN Multidrug-resistant Organism and Clostridium difficile Infection (MDRO/CDI) Module – protocol and instructions, training, and forms for performing infection surveillance, laboratory-identified (LabID) event reporting, prevention process and active surveillance testing outcome measures. Prevention process measures include hand hygiene and gown and gloves use adherence. MDROs monitored include MRSA, VRE, Klebsiella spp., and Acinetobacter spp.
For more patient resources, please see the Consumer and Public Information page
Acinetobacter baumannii
APIC Guide to the Elimination of Multidrug-Resistant Acinetobacter baumannii Transmission in Healthcare Settings
Carbapenem-resistant Enterobacteriaceae (CRE)
CDC Vital Signs Report: Making Health Care Safer - Stop Infections from Lethal CRE Germs Now (March 2013) - information on what CRE are, how they are spread, and what the federal government, states and communities, healthcare administrators, healthcare providers, and patients can do to prevent them
CRE: Detect and Protect (April 2013) – Powerpoint presentation developed by VDH for healthcare personnel in acute care or long-term care facilities to provide an overview of CRE epidemiology, surveillance, and prevention strategies
CRE fact sheet for assisted living facilities and nursing homes
Guidance for Control of Infections with Carbapenem-Resistant or Carbapenemase-Producing Enterobacteriaceae in Acute Care Facilities, MMWR, March 20, 2009
Morbidity and Mortality Weekly Report (MMWR) – March 6, 2013 – more detailed information on methodology of Vital Signs report
Summary Recommendations for Acute and Long-Term Care Facilities for Control of CRE (April 2013) – document developed by VDH that summarizes the 2012 CDC CRE toolkit and discusses when to call the local health department
MRSA fact sheet for assisted living facilities and nursing homes
OSHA Hospital e-Tool: MDRO/MRSA module - information to help stop the spread of MRSA among employees and others working in healthcare and other industries.
Personal prevention of MRSA skin infections – for patients
SHEA Patient Education Guide (MRSA)– fact sheet that educates patients and their families about 7 types of HAIs (including MRSA) and how to work with healthcare professionals to prevent them.
Vancomycin-resistant Enterococci (VRE)
CDC website – VRE
SHEA Patient Education Guide (VRE) – fact sheet that educates patients and their families about 7 types of HAIs (including VRE) and how to work with healthcare professionals to prevent them.
VRE fact sheet for assisted living facilities and nursing homes
Vancomycin-intermediate or Vancomycin-resistant Staphylococcus Aureus (VISA/VRSA)
CDC clinical reminder (2010) – discusses the important role of clinical laboratories in the diagnosis of VRSA cases to ensure prompt recognition, isolation, and management by infection control personnel
(Gorwitz RJ et al. Journal of Infectious Diseases. 2008:197:1226-34.)
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