Skip to main content

Online Nursing Continuing Education

Multidrug-Resistant Organisms (MDROs)




ANCC Accredited Nursing CE Provider

Wild Iris Medical Education, Inc. is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's Commission on Accreditation.

Provider approved by the California Board of Registered Nursing, Provider #12300.

Nurse practitioners may apply these contact hours to pharmacy continuing education and prescriptive authorization.

Course Availability: Expires December 1, 2016. You must score 70% or better on the test and complete the course evaluation to earn a certificate of completion for this CE activity. Wild Iris Medical Education, Inc., provides educational activities that are free from bias. The information provided in this course is to be used for educational purposes only. It is not intended as a substitute for professional healthcare.  Medical Disclaimer   Legal Disclaimer   Disclosures

Multidrug-Resistant Organisms (MDROs)

COURSE OBJECTIVE:  The purpose of this course is to provide an overview of the most common multidrug-resistant organisms encountered in healthcare settings and recommendations for preventing their spread.


Upon completion of this course, you will be able to:

  • Define the term “multidrug-resistant organism” (MDRO).
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of Clostridium difficile (C. diff).
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of carbapenem-resistant Enterobacteriaceae (CRE).
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of methicillin-resistant Staphylococcus aureus (MRSA).
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of vancomycin-resistant Enterococcus (VRE).
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of multi- and extensively drug-resistant tuberculosis.
  • Discuss risk factors, clinical manifestations, medical management, and methods to prevent or reduce the transmission of Acinetobacter.
  • List some of the clinical and economic consequences of MDRO infections.


Every year, over 2 million people in the United States become infected with bacteria that are resistant to antibiotics, and around 23,000 people die as a result of these infections (CDC, 2013a). Multidrug-resistant organisms, or MDROs, are bacteria that are resistant to current antibiotic therapy and, therefore, difficult to treat. MDROs can cause serious local and systemic infections that can be severely debilitating and even life-threatening.

In the past, MDROs were predominantly confined to healthcare facilities such as hospitals, long-term care facilities, and dialysis centers. However, in recent years, these organisms have been found in populations in a variety of community settings across the United States and the world, including schools, day-care centers, prisons, and other well-populated areas.

In a recent report, the CDC (2013a), along with experts in the field of infectious disease, assessed all current antibiotic-resistant bacteria according to seven factors:

  • Health impact
  • Economic impact
  • How common the infection is
  • A 10-year projection on how common it could become
  • How easily it spreads
  • Availability of effective antibiotics
  • Barriers to prevention

They then categorized these bacteria into three threat levels: urgent, serious, or concerning. Threats assigned to the urgent and serious categories require more diligent monitoring and prevention strategies. Threats in the category of concerning require less.

Hazard Level MDROs
Source: CDC, 2013a.
High-consequence antibiotic resistance threats because of significant risks identified across several criteria. These threats are not currently widespread but have the potential to become so and require urgent public health attention to identify infections and to limit transmission.
  • Clostridium difficile (C. difficile)
  • Carbapenem-resistant Enterobacteriaceae (CRE)
  • Drug-resistant Neisseria gonorrhoeae (cephalosporin resistance)
These are significant antibiotic-resistant threats. For varying reasons (e.g., low or declining domestic incidence or reasonable availability of therapeutic agents), they are not considered urgent, but these threats will worsen and may become urgent without ongoing public health monitoring and prevention activities.
  • Multidrug-resistant Acinetobacter
  • Drug-resistant Campylobacter
  • Fluconazole-resistant Candida (a fungus)
  • Extended spectrum β-lactamase producing Enterobacteriaceae (ESBLs)
  • Vancomycin-resistant Enterococcus (VRE)
  • Multidrug-resistant Pseudomonas aeruginosa
  • Drug-resistant non-typhoidal Salmonella
  • Drug-resistant Salmonella Typhi
  • Drug-resistant Shigella
  • Methicillin-resistant Staphylococcus aureus (MRSA)
  • Drug-resistant Streptococcus pneumoniae
  • Drug-resistant tuberculosis (MDR and XDR)
These are bacteria for which the threat of antibiotic resistance is low and/or there are multiple therapeutic options for resistant infections. These bacterial pathogens cause severe illness. Threats in this category require monitoring and in some cases rapid incident or outbreak response.
  • Vancomycin-resistant Staphylococcus aureus (VRSA)
  • Erythromycin-resistant Streptococcus Group A
  • Clindamycin-resistant Streptococcus Group B

This course will focus on the most common “urgent” and “serious” MDROs that occur within healthcare settings. Healthcare providers must be able to accurately identify these threats, care for patients suffering from these infections, and take measures to prevent further transmission of these infections.

People who are healthy are at low risk for developing MDRO infections. The risk factors for acquiring MDROs include:

  • An existing severe illness
  • An underlying disease or chronic condition
  • Receiving dialysis
  • Previous use of antibiotics
  • Invasive procedures or the use of medical devices (e.g., urinary catheters, endotracheal tubes, vascular catheters)
  • Repeat contact with the healthcare system (e.g., numerous hospital admissions)
  • Previous colonization with a MDRO
  • Advanced age (65 and older)
  • Taking immunosuppressant drugs
  • Complex surgeries (e.g., open abdominal and chest surgeries)
  • Chemotherapy for cancer treatment
    (CDC, 2013a)


Clostridium Difficile (C. difficile)

Clostridium difficile (C. difficile), sometimes called “C-diff,” is a gram-positive bacterium that causes severe diarrhea and, in some cases, inflammation of the colon. In 2000, a stronger C. difficile bacterium strain emerged that is resistant to antibiotics such as fluoroquinolones. This stronger strain is one of the reasons for this bacterium’s current urgent status from the CDC. In the United States, C. difficile causes around 250,000 infections (resulting in 14,000 deaths per year), affecting patients in the healthcare setting or causing hospitalization (CDC, 2013a).

Eighty percent of C. difficile cases are found in healthcare settings. Most patients who get this infection are on antibiotics to treat other infections. In the process of treatment, the antibiotics can also kill and disrupt the protective bacteria in the gastrointestinal system that help to fight off dangerous bacteria such as C. difficile. The C. difficile bacterium is responsible for 15%–25% of all episodes of antibiotic-associated diarrhea (CDC, 2010a).


Clusters of Clostridium difficile bacterium from a stool sample culture. (Source: Janice Carr, Centers for Disease Control and Prevention, Public Health Image Library.)


Patients at risk for the development of illness due to C. difficile predominately include the elderly. However, this bacterium has recently been reported in traditionally healthy people, such as peripartum women (CDC, 2010a). Others who are at risk for the development of illness due to C. difficile include patients with any of the following:

  • Antibiotic exposure
  • Proton pump inhibitor treatment
  • Recent medical care
  • Gastrointestinal surgery/manipulation
  • Long length of stay in healthcare settings (including hospitals and long-term care settings)
  • A serious underlying illness
  • Immunocompromising conditions
  • Advanced age (65 and older)
    (CDC, 2010a)

The Clostridium difficile bacterium is spread in fecal matter and can be transmitted via surfaces such as countertops and toilets and equipment such as rectal thermometers. However, the bacterium is most commonly transmitted on the hands of healthcare providers (CDC, 2010a).


A recent study found that a daily cleaning regimen using germicidal bleach wipes reduced the incidence and time between cases of healthcare-acquired Clostridium difficile infections on hospital units with a high incidence of hospital-acquired infections. The cleaning regimen reduced hospital-acquired C. difficile infections by 85%, from 24.2 to 3.6 cases per 10,000 patient-days, and extended median time between hospital-acquired cases from 8 to 80 days.

Source: Orenstein et al., 2011.


Patients affected by C. difficile may exhibit watery diarrhea, fever, loss of appetite, nausea, and abdominal pain and tenderness. Clinical manifestations can range from mild diarrhea to death. Patients carrying the C. difficile bacterium can be colonized with the bacterium and not exhibit any clinical manifestations. However, patients may also present with symptoms of pseudomembranous colitis, toxic megacolon, kidney failure, perforation of the colon, and sepsis (CDC, 2010a).

Healthcare providers treating patients affected by resistant strains of the Clostridium difficile bacterium have the unique challenge of finding effective treatment for these patients.

The usual treatment for mild to moderate C. difficile infection (CDI) includes, if possible, stopping antibiotics being given for other purposes and/or treatment with metronidazole (Flagyl), vancomycin (Vancocin), or fidaxomicin (Dificid). In order to reduce selective pressure for vancomycin resistance in Enterococci, current guidelines recommend the first-line use of metronidazole over vancomycin. However, recent reports suggest that the new strain may not respond as well to treatment with metronidazole despite the absence of laboratory evidence of metronidazole resistance. This may be due to increased virulence in the new strain. Depending upon the severity of the CDI, metronidazole is likely to be the appropriate first-line therapy for most cases. Regardless of what therapy is used, patients should be carefully monitored to be sure they are responding to therapy and that there is no deterioration in their condition (CDC, 2010a).

Recent research shows promising results with fecal microbiota transplantation (FMT, also known as a stool transplant) for recurrent infections with C. difficile (Knight & Surawicz, 2013). FMT restores the healthy bacteria in the intestine by placing the stool of a donor into the infected patient’s colon via colonoscope or nasogastric tube. Donor stools are carefully screened for parasites, viruses, bacteria, and antibodies prior to transplantation.

Patients should be cared for in private rooms or in cohorts with other patients affected by the bacterium. These patients should also be placed on Contact Precautions while being treated. Contact Precautions include the use of gown and gloves when entering the patient room and during patient care; attention to hand hygiene after patient care; and meticulous cleaning of any shared medical equipment with hypochlorite-based (bleach) disinfectants, as C. difficile spores can survive with other routine cleaning products that do not contain bleach (CDC, 2010a).

Patients infected with C. difficile can continue to shed the organism for a number of days following the cessation of diarrhea symptoms. It is recommended to continue isolation for several days after symptoms resolve or until discharge.


Hand hygiene to prevent the spread of C. difficile is an important consideration for healthcare providers caring for patients. Along with Contact Precautions, which include the use of gown and gloves to protect against contamination, meticulous hand hygiene is essential. Because alcohol is not effective against C. difficile spores, the use of soap and water is more efficacious than alcohol-based hand sanitizers.

Source: CDC, 2010a.

Carbapenem-Resistant Enterobacteriaceae (CRE)

According to the CDC (2013a), carbapenem-resistant Enterobacteriaceae (CRE) bacteria (including Klebsiella spp. and E. coli) are responsible for more than 9,000 healthcare-associated infections annually, with as many as 600 deaths because of lack of effective antibiotics. In recent years, CRE infections have been recognized in healthcare settings as a cause of difficult-to-treat infections associated with high mortality (CDC, 2013b).


CRE can cause various body system infections, including bloodstream infections, ventilator-associated pneumonia, and intra-abdominal abscesses. However, most CRE infections involve the urinary tract, most often seen in patients who have urinary catheters or urinary retention (CDC, 2013c).

Risk factors for CRE include:

  • Exposure to healthcare settings (hospital and long-term care settings)
  • Exposure to antimicrobials
  • Poor functional status
  • Exposure to an intensive care unit
  • Exposure to medical devices (e.g., central venous catheters, urinary catheters)
  • Mechanical ventilation
    (CDC, 2013c)

CRE infections are usually transmitted from person to person via the hands of healthcare personnel or by contaminated medical equipment. As Enterobacteriaceae is commonly found in stool or wounds, contact with these is particularly concerning. It is important to use personal protective equipment during direct care and good hand hygiene following exposure to the patient’s immediate environment, especially when cleaning up stool or changing wound dressings (CDC, 2013c).


Symptoms of CRE infection are usually associated with the site that is infected (e.g., cough if in the lungs, urinary symptoms if in the bladder) but can also include general symptoms such as fever or chills.

The past several decades have been witness to the spread of CRE infections with increasing resistance to broad-spectrum antibiotics. Treatment strategies currently include agents in the carbapenem antimicrobial class (e.g., imipenem, meropenem, doripenem, and ertapenem) (CDC, 2013b).

Patients should be cared for in private rooms or in cohorts with other patients affected by the bacterium. Any medical devices that are the suspected cause of infection should be cultured and removed. Patients should be placed on Contact Precautions while being treated. Contact Precautions include the use of gown and gloves when entering the patient room and during patient care and meticulous attention to hand hygiene before and after patient care (CDC, 2012).


Methicillin-Resistant Staphylococcus Aureus (MRSA)

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staphylococcal organism resistant to traditional antibiotic therapy, including methicillin, nafcillin, oxacillin, amoxicillin, penicillin, and cephalosporins. In 2011, there were 80,461 reported cases and 11,285 reported deaths related to MRSA (CDC, 2013a). Staph bacteria, including MRSA, are one of the most common causes of healthcare-associated infections.

Over the past decade, MRSA infections appear to be declining. Between 2005 and 2011, overall rates of MRSA dropped 31%. This is in large part due to the focus on preventing central line–associated bloodstream infections in the hospital setting. However, the rates of MRSA infection are increasing in community settings (CDC, 2013a).


Magnified 20,000X, this colorized scanning electron micrograph (SEM) depicts a grouping of methicillin-resistant Staphylococcus aureus (MRSA) bacteria. (Source: Janice Carr, Centers for Disease Control and Prevention, Public Health Image Library.)


Since MRSA infections can be spread in healthcare and community settings, everyone is at risk. However, people who live in crowded and/or unclean conditions or who have a poor immune system are more susceptible to infection by MRSA. When MRSA is acquired in a healthcare facility—such as a hospital, long-term care facility, or dialysis center—it is referred to as healthcare-associated MRSA, or HA-MRSA. If MRSA is acquired in a community setting—such as a prison, homeless shelter, or day-care center—it is referred to as community-associated MRSA, or CA-MRSA.

Healthcare-associated MRSA is transmitted via personal contact with contaminated items such as dressings or other infected materials. It is also spread via healthcare providers’ hands and medical instruments, such as stethoscopes. Community-associated MRSA is transmitted through close personal contact with infected individuals or by sharing personal items such as towels and razors.


MRSA is normally found in the nose and pharynx and may not cause illness in its host. However, if this organism enters open cuts, incisions, or wounds, severe infection throughout the body may result. MRSA initially affects the skin and soft tissue, but it can quickly cause sepsis and/or pneumonia that may lead to death. An infected patient often visits a healthcare provider with a fever and an area of skin that is:

  • Red
  • Swollen
  • Painful
  • Warm to the touch
  • Full of pus or other drainage

Often the affected area has a furuncle (abscessed hair follicle or “boil”), carbuncle (coalesced mass of furuncles), or an abscess. The area may also resemble a spider bite.


A cutaneous abscess located on the back of a patient, caused by MRSA. (Source: Gregory Moran, MD, Centers for Disease Control and Prevention.)

The primary method of treatment for MRSA infection includes incising and draining infected areas. However, treatment with empiric antibiotic therapy may also be necessary. Often, vancomycin or linezolid is used. If initial methods to treat a MRSA infection are unsuccessful, it is imperative that healthcare providers consult infectious disease specialists.

Vancomycin-Resistant Enterococcus (VRE)

Enterococci are a type of bacteria normally present in the gastrointestinal tract and genital tract of some women. Enterococci can cause infections in wounds, the blood stream, and the urinary tract. Some people carry the bacteria but are unaffected by it. These people are said to be “colonized.” When Enterococcus does cause an infection, the infection is treated with the antibiotic vancomycin. In recent years, Enterococci have become resistant to vancomycin treatment, giving rise to vancomycin-resistant Enterococci, or VRE. The two organisms that are predominately responsible for VRE include Enterococcus faecalis and Enterococcus faecium.


Scanning electron micrograph (SEM) image of vancomycin-resistant gram-positive Enterococci sp. bacteria. (Source: Janice Haney Carr, Centers for Disease Control and Prevention, Public Health Image Library).

VRE most commonly occurs in hospital and long-term care settings. However, it has also been seen in community settings. An estimated 66,000 healthcare-associated Enterococci infections occur each year, with 20,000 of these being vancomycin-resistant infections. VRE results in 13,000 deaths annually (CDC, 2013a).


According to the CDC (2013a), patients at risk for VRE include those with a history of:

  • Treatment with the antibiotic vancomycin, or other antibiotics, for long periods of time
  • Hospital admission, particularly involving prolonged therapy with antibiotics
  • A weakened immune system, such as patients in intensive care, cancer, or transplant units
  • Surgical procedures, such as abdominal or chest surgery
  • Long-term in-dwelling medical devices, such as urinary catheters or central intravenous (IV) catheters
  • Positive test results for VRE colonization

VRE is found in the blood, urine, and feces. Therefore, it is often transmitted on the hands of providers who care for a patient with VRE and inadvertently pass the infection on to other patients. VRE can also be transferred from patient to patient. VRE can live for several weeks on surfaces such as countertops, bedrails, and door handles and can be transmitted via contact with these surfaces.


The clinical manifestations of VRE depend on the site of the infection. If the bacterium is located in the urine, symptoms of a urinary tract infection will be evident, including lower back pain, urinary urgency and frequency, and pain with urination. If the bacterium infects a wound, the area will typically exhibit swelling, redness, and other common signs of a wound infection. Patients with a VRE infection may also have fever, chills, and diarrhea, as well as other general signs of an infection.

Once identified through laboratory testing, VRE can be treated with antibiotics, preferably penicillin G or ampicillin. However, newer drugs such as linezolid, daptomycin, or tigecycline may be needed if the VRE strain is resistant to penicillin G or ampicillin. Infectious disease specialists should be consulted to determine the best plan of care for patients with VRE.

Patients with VRE infections are placed in private rooms or in cohorts with other patients who have VRE. Healthcare providers should take extra precautions to prevent the spread of the bacteria to other hospitalized patients (CDC, 2013a).

Multi- and Extensively Drug-Resistant Tuberculosis

Multidrug-resistant tuberculosis (MDR-TB) is caused by Mycobacterium tuberculosis that are resistant to isoniazid and rifampicin, which are used to treat traditional strains of TB. MDR-TB may be caused by either primary infection with resistant bacteria or may develop in the course of a patient’s treatment. Extensively drug-resistant TB (XDR-TB) is a form of TB caused by bacteria that are resistant to isoniazid and rifampicin (i.e., MDR-TB) as well as to any fluoroquinolone and any of the second-line anti-TB injectable drugs (amikacin, kanamycin, or capreomycin) (WHO, 2013).


Mycobacterium tuberculosis culture revealing this organism’s colonial morphology. (Source: George Kubica, Centers for Disease Control and Prevention, Public Health Image Library.)

According to the World Health Organization (2013), there were around 630,000 cases of MDR-TB present in the world in 2011. It is estimated that about 9% of these cases were XDR-TB. In the United States, the CDC (2013a) reports 1,042 annual cases of MDR-TB, with an estimated 50 deaths per year.


While anyone can acquire MDR- or XDR-TB, the following individuals are at risk for developing these resistant infections:

  • TB patients who are not compliant with anti-tubercular drug therapy
  • TB patients prescribed anti-tubercular drugs that are not effective
  • Individuals who develop TB after having been treated for TB previously
  • Individuals exposed to patients with MDR- and/or XDR-TB
  • Individuals living or visiting areas where MDR- and/or XDR-TB is prevalent
  • The elderly, poor, and/or those with a weakened immune system
    (CDC, 2010b)

MDR-TB and XDR-TB are spread in the same way that traditional strains of tuberculosis are spread. TB predominately affects the lungs and is transmitted through the air via respiratory droplets when a patient coughs, sneezes, laughs, talks, etc. TB droplets can live in the air for several hours and infect others who breathe in the droplets. TB is prevalent in closed or crowded areas, such as prisons, homeless shelters, long-term care facilities, and hospitals.


Patients with MDR-TB and XDR-TB exhibit clinical manifestations in the same manner as patients with traditional strains of TB. Clinical manifestations of pulmonary tuberculosis may include all or some of the following: night sweats, fever, chills, weight loss, coughing, hemoptysis, and chest pain. Although TB predominantly affects the pulmonary system, it may affect other parts of the body, such as the kidneys, meninges, bones, joints, and abdomen. Therefore, other clinical manifestations, depending on the parts of the body affected by the Mycobacterium tuberculosis bacterium, may be present in a patient with TB.

According to the World Health Organization (2010b), “while drug-resistant TB is generally treatable, it requires extensive chemotherapy (up to 2 years of treatment) with second-line anti-TB drugs, which are more costly than first-line drugs, and which produce adverse drug reactions that are more severe, though manageable.”

Patients with pulmonary tuberculosis may be treated in the home. If hospitalized, these patients should be placed in respiratory isolation in a private room with negative pressure. Patient rooms should also be labeled with a sign that indicates the need to adhere to the principles of airborne precautions. N-95 respirator masks should be worn by healthcare providers when providing care to all patients with TB, regardless of the strain of TB present.


Acinetobacter is a gram-negative bacterium that is often found in soil and water and on the skin of healthy people, particularly healthcare providers. Multidrug-resistant Acinetobacter strains are resistant to most antibiotics. Acinetobacter can cause pneumonia and bloodstream infections in the critically ill patient (CDC, 2013a).


Clusters of Acinetobacter baumannii. (Source: Janice Haney Carr, Centers for Disease Control and Prevention, Public Health Image Library.)

According to the CDC (2010c), Acinetobacter accounts for about 12,000 healthcare-associated infections in the United States each year. Around 7,000 are multidrug-resistant, with an estimated 500 deaths associated with these infections.


Acinetobacter bacterium is most often found in burn units, intensive care units, and other units that care for severely ill patients (CDC, 2010c). Patients with weakened immune systems or chronic diseases such as diabetes mellitus are more susceptible to an Acinetobacter bacterium. Acinetobacter is also associated with intensive care unit–acquired pneumonia.

The Acinetobacter bacterium is transmitted from person-to-person contact, contact with contaminated surfaces, or environmental exposure. Acinetobacter bacterium can last quite some time on the hands of healthcare providers and also in the environment on counters and other areas within healthcare settings. Healthcare providers who are colonized with Acinetobacter can spread the infection while not exhibiting clinical manifestations of infection.


Acinetobacter bacterium can cause a variety of infections, including blood and wound infections. Therefore, the clinical manifestations will depend on the site of infection. As previously mentioned, Acinetobacter can also cause pneumonia. Patients with pneumonia caused by the Acinetobacter bacterium will exhibit fever, chills, and/or a cough.

Multidrug-resistant strains of Acinetobacter may be treated with imipenem, meropenem, ampicillin, sulbactam, tigecycline, and amikacin and are sometimes susceptible only to polymyxins (colistin and polymyxin B), a class of antimicrobial drugs that has not been in widespread use for several decades and is more toxic than most currently used antimicrobial drugs (Fishbain & Peleg, 2010). However, treatment decisions for infections caused by the Acinetobacter bacterium should be made on a case-by-case basis.


Preventing the spread of multidrug-resistant organisms is vital to the safety and well-being of patients who are hospitalized as well as individuals who are susceptible to infection due to unsanitary or crowded living conditions or a weakened immune system. It is the responsibility of all healthcare providers not only to aid in preventing the development of multidrug-resistant organisms but also to teach patients and the public about the prevention and transmission of multidrug-resistant organisms.

CDC’s Four Core Actions

The CDC (2013a) recommends four core actions to prevent antibiotic resistance, including:

  • Preventing infections/preventing the spread of resistance
  • Tracking epidemiological trends and resistance patterns
  • Improving antibiotic prescribing/stewardship
  • Developing new drugs and diagnostic tests

Preventing infections from developing will reduce the amount of antibiotics used, which in turn will slow the pace of new and existing antibiotic resistance. Preventing infections also prevents the spread of resistant bacteria. With this in mind, the CDC (2013a) is working to prevent infections and antibiotic resistance in healthcare settings through infection control guidelines, implementation of tracking systems, and guidance on antibiotic use for healthcare providers.


One of the most essential components in the fight to control MDROs is the surveillance of MDROs. The study of epidemiological trends, emerging pathogens, and the effectiveness of interventions are all part of MDRO surveillance. The CDC’s National Healthcare Safety Network (NHSN) is used by healthcare systems to report infections, antibiotic use, and antibiotic resistance. The NHSN allows tracking and benchmarking of data to target areas of concern, to understand where to make improvements, and to track success of prevention efforts (CDC, 2013a).


Healthcare providers with prescribing privileges must be knowledgeable regarding the administration of antimicrobial agents to control the transmission of MDROs. The CDC (2013a) recommends these best practices to promote antibiotic stewardship:

  • Ensure all antibiotic order forms include instructions on dose, duration, and indications
  • Check cultures before starting antibiotic treatment
  • Take an “antibiotic timeout,” reassessing antibiotics after 48–72 hours

All healthcare providers play an important role in this process and should be knowledgeable about the efforts to use antimicrobials judiciously and to educate their patients about these efforts.


The CDC’s national “Get Smart” campaign focuses on improving antibiotic prescribing in both inpatient and outpatient settings. Each November, the CDC provides focused messages to raise awareness among patients, healthcare providers, hospital administrators, and policy makers about the threat of antibiotic resistance and the need to decrease unnecessary antibiotic use. The campaign aims to reduce the rise in rate of antibiotic resistance by:

  • Promoting adherence to appropriate prescribing guidelines among providers
  • Decreasing antibiotic overuse for viral upper respiratory infections among healthy adults and the parents of young children
  • Increasing adherence to prescribed antibiotics for upper respiratory infections

Source: CDC, 2013a.


Antibiotic resistance occurs as part of a natural evolution process and can only be slowed, not stopped completely. Because of this, new antibiotics that cover a broad spectrum are always needed to keep up with developing resistant bacteria. However, the number of new antibiotics developed in the past 30 years has decreased on a steady basis, leaving fewer options to treat resistant bacteria. Using antibiotics only when needed and for the shortest time possible is one of the most important strategies to prevent new drug-resistant bacteria. New diagnostic tests to detect infections are also needed to track the development and rate of resistance.

Infection Control Precautions

The implementation of Standard Precautions and Contact Precautions are necessary to aid in preventing the transmission of MDROs. Standard Precautions instruct healthcare providers to wash hands often and effectively prior to and after all patient contact and to use PPE (personal protective equipment) when coming into contact with blood or body fluids. Such precautions are necessary with all patients and effective in preventing transmission from potentially colonized patients (CDC, 2013a).

Early detection and identification of patients with MDROs is an important consideration for patients in the healthcare setting. Healthcare providers should be aware of patients at high risk for developing MDROs, such as those patients who are chronically ill in long-term care facilities and ICU settings. Screening high-risk patients who are colonized with CRE or VRE can also be performed on admission to identify the immediate need for Contact Precautions and thus prevent transmission to other patients.

Precautions used when caring for patients with MDROs vary based on the organism involved. However, Contact Precautions are often used with these patients and involve wearing PPE prior to entering the patient’s room and discarding that equipment prior to leaving the patient’s room. Additionally, dedicated equipment, such as stethoscopes, blood pressure cuffs and machines, etc., should be placed and used only in the patient’s room. These patients are often assigned to private rooms or placed in cohorts of patients with the same MDRO in the same room or patient-care area. Cohorts can be arranged in semi-private rooms with other patients who are also under special precautions.

Environmental Precautions

Many MDROs can survive for quite some time on environmental surfaces in healthcare facilities and in patient homes. Therefore, it is imperative that healthcare providers, environmental services personnel, and patients understand the importance of both meticulous hand washing and proper cleaning methods for preventing the spread of MDRO infections. Some facilities may choose to assign dedicated staff to targeted patient care areas to enhance consistency of proper environmental cleaning and disinfection services.

Reinforcing and monitoring of cleaning performance may be needed to ensure consistent cleaning and disinfection of surfaces in close proximity to the patient (e.g., bedrails, carts, bedside commodes, doorknobs, faucet handles). In addition, the regular testing of environmental surfaces and subsequent education of all personnel is essential to help prevent the spread of MDROs.

Patient and Family Education

With the constant need to protect patients from MDROs, healthcare providers must be willing and able to educate patients and their families regarding MDROs. Education for each patient must be tailored to the MDRO causing the infection. However, there are a few general measures that healthcare providers can teach patients and their families to help prevent the transmission of MDROs.

When at a healthcare facility:

  • Employ meticulous hand washing
  • Do not use alcohol-based hand sanitizer in the presence of diarrhea
  • Question healthcare workers who do not wash their hands or use gloves
  • Encourage at-risk patients to get the influenza/pneumococcal vaccine prior to discharge from the hospital
  • Ask healthcare providers about infection control at home (including cleansing surfaces regularly and disposing of infectious items)

When at home:

  • Employ meticulous hand washing before eating and after toileting
  • Do not use alcohol-based hand sanitizer in the presence of diarrhea
  • Immediately report symptoms of infection to a healthcare provider
  • Complete the full course of antibiotics even when feeling better
  • Stay home when feeling ill
  • Sneeze and cough into one’s elbow
  • Dispose of tissues immediately to avoid leaving them on tables or counters

With the increased rate of infection caused by multidrug-resistant organisms, healthcare providers are charged with the responsibility of preventing and detecting MDROs as well as educating the public about these organisms. It is imperative that healthcare providers learn about and remain up-to-date on resistant organisms, prevention measures, and treatment options.


MDROs add considerable costs to the healthcare system. Studies have estimated that 20% of emergency department visits are attributed to the use of antibiotics (either from side effects, allergic reactions, or drug-resistance effects). Antibiotic resistance adds around $20 billion in excess direct healthcare costs. The overuse of antibiotics is the single most important factor that has led to the current issue with drug-resistant bacteria. Studies have shown that up to 50% of all antibiotics prescribed are not needed (CDC, 2013a).

Efforts to improve the effective use of antibiotics and prevent MDROs can positively impact both clinical and economic outcomes. Improved patient outcomes as well as pharmacy cost savings are direct results of MDRO prevention and infection control (CDC, 2013a). Indirect results are cost savings related to patient care and shorter hospital stays, decreasing total healthcare spending. A study from the University of Maryland showed that one antibiotic stewardship program saved $17 million over a period of 8 years (CDC, 2013c).


MDROs are increasing in prevalence. Providers working within the healthcare setting can make a difference by being aware of patients at high-risk for developing MDROs as well as preventing the spread of infection. Education regarding early detection, infection control, and hand hygiene are key elements to consider. Reducing risk for patients is also important; this includes reducing exposure to long-term invasive devices and being aware of patients who are on long-term antibiotic regimens. On a larger scale, programs that promote antibiotic stewardship at all levels in the healthcare system have the potential to reduce the overall incidence of MDROs.


NOTE: Complete URLs for references retrieved from online sources are provided in the PDF of this course (view/download PDF from the menu at the top of this page).

Centers for Disease Control and Prevention (CDC). (2013a). Threat report 2013. Antibiotic resistance threats in the United States, 2013. Retrieved from

Centers for Disease Control and Prevention (CDC). (2013b). Vital signs: carbapenem-resistant Enterobacteriaceae. Morbidity and Mortality Report, 62(09), 165–70.

Centers for Disease Control and Prevention (CDC). (2013c). Carbapenem-resistant Enterobacteriaceae (CRE) infection: clinician FAQs. Retrieved from

Centers for Disease Control and Prevention (CDC). (2012). Guidance for control of carbapenem-resistant Enterobacteriaceae (CRE). Retrieved from

Centers for Disease Control and Prevention (CDC). (2010a). Frequently asked questions about Clostridium difficile for healthcare providers. Retrieved from

Centers for Disease Control and Prevention (CDC). (2010b). Fact sheet: multidrug-resistant tuberculosis (MDR-TB). Retrieved from

Centers for Disease Control and Prevention. (2010c). Acinetobacter in healthcare settings. Retrieved from

Fishbain J & Peleg AY. (2010). Treatment of Acinetobacter infections. Clin Infect Dis, 51, 79.

Knight CL & Surawicz CM. (2013). Clostridium difficile infection. Medical Clinics of North America , 97(4), 523–36.

Orenstein R, Aronhalt KC, McManus JE, & Fedraw LA. (2011). A targeted study to wipe out Clostridium difficile. Infect Control Hospital Epidemiology, 32(11), 1137–9.

World Health Organization (WHO). (2013). What is multidrug-resistant tuberculosis and how do we control it? Retrieved from

World Health Organization (WHO). (2010a). Drug-resistant tuberculosis now at record levels. Retrieved from

World Health Organization (WHO). (2010b). Fact sheet: tuberculosis. Retrieved from

Table of Contents Back to Top