Multidrug Resistance: A Growing Threat of Carbapenem-Resistant Gram-Negative Organisms in Health Care

Nurses are well aware of the problems with multidrug-resistant organisms (MDROs) and their ubiquitous presence across health care settings. Care issues and outcomes among patients with MDROs such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), and Clostridioides difficile (C. diff) have increased awareness, but MDROs remain a growing challenge in the provision of care in virtually all health care settings.

Carbapenem-resistant Gram-negative bacteria, another example of MDROs, have emerged as one of the most urgent public health challenges globally. Organisms such as carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and carbapenem-resistant Acinetobacter baumannii (CRAB) are associated with high morbidity, mortality, prolonged hospitalization, and limited treatment options. According to the World Health Organization (WHO), carbapenem-resistant A. baumannii and carbapenem-resistant Enterobacterales are among the highest-priority pathogens due to their rapid spread and severe clinical consequences (WHO, 2024).

Mechanisms of Carbapenem Resistance

Carbapenem resistance develops when bacteria change in ways that allow them to survive despite antibiotic treatment. Nurses and other health care personnel benefit from understanding these mechanisms because they directly relate to infection prevention activities, equipment cleaning and disinfection, and antimicrobial stewardship efforts.

Examples of how resistance develops are outlined below:

  1. Bacteria Produce Enzymes That Break Down the Antibiotic (Carbapenemase production)

Some bacteria create special enzymes that destroy carbapenem antibiotics before they can work. These are called carbapenemases. Common types of these enzymes include KPC (Klebsiella pneumoniae carbapenemase), NDM (New Delhi metallo-beta-lactamase), VIM (Verona integron-encoded metallo-beta-lactmase), IMP (Imipenemase metallo-beta-lactamases), and OXA-48 (Oxacillinase-48).  These enzyme abbreviations/names may be familiar, as they have been seen […]

2026-01-05T11:14:29-05:00January 5th, 2026|infectious diseases, Nursing, Public health|0 Comments

Infections in Acute Care: Still More to Do

A sharply increased focus on hospital-acquired infections (HAIs).

This month marks the 14th anniversary of the National Healthcare Safety Network (NHSN), the CDC’s data repository for health care–associated infections. Since 2005, when a limited number of hospitals began reporting infections data, the health care community has sharply increased its focus on the prevention, early recognition, and treatment of infections in the hospital. Research on risk factors, closer attention to limiting device use (urinary catheters, central lines), and support for meticulous hand hygiene and environmental cleaning protocols have decreased rates of CAUTIs, CLABSIs, and surgical site infections.

The risk is always there.

Still, as nurses well know, hospitalized patients remain at increased risk for developing infections, especially if they are immunosuppressed or have diabetes, need invasive devices, have many comorbidities, or stay in a critical care unit.

The current evidence reviewed.

In “Infection in Acute Care: Evidence for Practice” in this month’s AJN, Douglas Houghton reviews the latest evidence on common infections in acute care settings, including community- and hospital-acquired pneumonia, surgical site infections, and C. difficile. […]

2019-10-09T10:09:54-04:00October 9th, 2019|infection control, Nursing|1 Comment

The Real and Evolving Threat of Superbugs: A Primer

pillsinspaceJust how super is the latest superbug? The good news is that the infected U.S. patient has recovered. The bad news:  mcr-1, the resistance gene identified in this strain of E. coli, has brought us another frightening step closer to a “post-antibiotic” era.

In recent years, antimicrobial resistance among Gram-negative bacteria (E. coli, Klebsiella, Pseudomonas, Acinetobacter, Salmonella, and others) has been a growing public health concern. Most of the increase in resistance has been the result of mobile genetic elements that can easily transfer resistance from one bacterium to another, allowing bacteria to “catch” antibiotic resistance from one another.

To make matters worse, resistance enzymes are often packaged together. One genetic “cassette” can carry multiple resistance determinants, thereby spreading resistance to more than one class of antibiotics at the same time.

Early on, we relied on the carbapenem class of antibiotics to treat infections caused by multidrug-resistant (MDR) organisms such as the “ESBLs” (extended-spectrum beta-lactamase-producing organisms). But carbapenemase-producing organisms soon developed, and resistance to carbapenems spread quickly.

In 2009, the emergence of a “super” kind of carbapenem resistance gene, ndm-1 (New Delhi metallo-beta-lactamase) was found to be highly resistant to many antibiotic classes, including:

  • the carbapenems and other beta-lactams (penicillin derivatives and cephalosporins)
  • the fluoroquinolones (ciprofloxacin, levofloxacin, et al)
  • the aminoglycosides (gentamicin, amikacin, et al).

These antibiotic classes include the main drugs used to treat […]

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