Antibiotic Resistance Gene Detection Associated with Higher Rates of Mortality

Antibiotic Resistance Gene Detection Associated with Higher Rates of Mortality

AT A GLANCE

• A gene associated with severely antimicrobial-resistant pathogens was widely detected in antibiotic-resistant infections in a New York health system.
• The bla_NDM gene is found in some organisms that produce carbapenemases, enzymes that break down antibiotics including carbapenem, penicillin, cephalosporin and monobactam.
• Bla_NDM was detected in 38% of blood samples and 45% of urine samples positive for these organisms, also known as CPOs.
• Bla_NDM in blood samples was associated with mortality rates of 48% and was a contributor to elevated overall CPO infection mortality.
• Testing of CPOs can inform individual treatment, improve outcomes and inform antimicrobial stewardship efforts.

A gene that enables bacteria to evade treatment was the most common and deadly among carbapenemase-producing organism (CPO) infections in a New York health system, according to new findings presented at IDWeek 2024. CPOs harbor different genes that require tailored treatment. Patient outcomes can depend on care teams' ability to quickly identify and deploy appropriate therapy for each.

The bla_NDM gene was detected in 38% of blood and 45% of urine samples positive for bacteria that produce carbapenemase enzymes capable of breaking down antibiotics. Among health system patients, NDM - the enzyme produced by the bla_NDM gene - was associated with mortality of up to 48%. NDM contributed to elevated mortality among all patients with CPO blood infections, according to the study.

Researchers examined health records of hospitalized patients with positive blood and urine cultures for a CPO from January 2021 to December 2023. A total of 71 CPO-positive samples from 10 hospitals were included in the analysis.

"There's no one-size-fits-all treatment for CPO infections - you have to know exactly what you're treating, all the way down to the genetics," said Aya Haghamad, PharmD, pharmacy advisor at Northwell Health and lead author of the study. "Our study underscores how important it is to be able to identify carbapenemases - doing so allowed our team to improve patient outcomes and ensure appropriate prescribing of antimicrobial therapies."

CPO infections are often multidrug resistant. Carbapenemase enzymes can break down a variety of antibiotics, including carbapenems, penicillins, cephalosporins and monobactams. Researchers noted that the prevalence of CPO infections has increased in recent years, and effective management of patients with CPOs requires knowledge of the specific enzyme they produce.

In addition to Dr. Haghamad, study co-authors include: Ryan Shou, PharmD; Kirby An, PharmD; Jamie Lemon, PhD; Stefan Juretschko, PhD; and Vincent Streva, PhD.

About IDWeek
IDWeek is the joint annual meeting of the Infectious Diseases Society of America, the Society for Healthcare Epidemiology of America, the HIV Medicine Association, the Pediatric Infectious Diseases Society and the Society of Infectious Diseases Pharmacists. IDWeek is a recognized forum for peer-reviewed presentations of new research on scientific advances and bench-to-bedside approaches in prevention, diagnosis, treatment and epidemiology of infectious diseases, including HIV, across the lifespan. For more information, visit www.idweek.org.