A recent report from the Centers for Disease Control and Prevention (CDC), published in the Annals of Internal Medicine, documents a significant increase in NDM-producing carbapenem-resistant Enterobacterales (NDM-CRE) infections in the United States. According to the CDC, these drug-resistant bacteria present serious treatment challenges and have become more common over the past several years.
The report states that between 2019 and 2023, NDM-CRE infections rose by over 460% nationwide. These infections include pneumonia, bloodstream infections, urinary tract infections, and wound infections. They are difficult to treat due to resistance to most available antibiotics and can be fatal. The CDC notes that detection is also problematic because many clinical laboratories lack adequate testing capacity.
"This sharp rise in NDM-CRE means we face a growing threat that limits our ability to treat some of the most serious bacterial infections," said Danielle Rankin, an epidemiologist in CDC's Division of Healthcare Quality Promotion. "Selecting the right treatment has never been more complicated, so it is vitally important that healthcare providers have access to testing to help them select the proper targeted therapies."
NDM-CRE belongs to a group of bacteria known as carbapenem-resistant Enterobacterales (CRE). The "NDM" refers to New Delhi metallo-β-lactamase, an enzyme that makes these bacteria resistant to nearly all antibiotics.
In a previous 2022 special report titled COVID-19: U.S. Impact on Antimicrobial Resistance, the CDC reported about 12,700 CRE infections and 1,100 related deaths in 2020. The current rise in NDM-CRE may contribute further to these numbers.
The CDC outlines several reasons for concern:
- There are few effective treatments for NDM-CRE infections.
- Because NDM-CRE was previously rare in the U.S., clinicians may not suspect it immediately when treating patients with CRE.
- Infections are associated with high rates of illness and death.
- Without strong infection prevention measures, NDM-CRE can spread rapidly within healthcare facilities and potentially into communities.
Factors contributing to this surge include gaps in infection control practices such as hand hygiene and disinfection procedures. Additionally, limited laboratory testing capacity delays identification of cases, slowing both treatment and infection control efforts.
The CDC urges healthcare providers to stay informed about national trends regarding NDM-CRE and local patterns of CRE cases. Providers should perform prompt testing for carbapenemase production when CRE is identified so that patients receive appropriate therapy quickly. When possible, they should use available laboratory resources or public health labs for this purpose.
Other recommendations include selecting antibiotics based on confirmed resistance mechanisms and adhering closely to infection prevention guidelines like wearing gowns and gloves during patient care. Facilities are encouraged to collaborate with state or local programs focused on healthcare-associated infections and antimicrobial resistance.
For further details on NDM-CRE prevention strategies or general information about these bacteria, readers can visit https://www.cdc.gov/cre/about/index.html or https://www.cdc.gov/antimicrobial-resistance-laboratory-networks/php/about/domestic.html.
