Study finds multidrug-resistant gram-negative bacteria high in long-term care

April 10, 2009

The prevalence of a certain form of drug-resistant bacteria, called multidrug-resistant gram-negative (MDRGN) organisms, far surpassed that of two other common antimicrobial-resistant infections in long-term care facilities, according to a study conducted by researchers at Hebrew SeniorLife's Institute for Aging Research.

Residents at long-term care facilities are one of the main reservoirs of antimicrobial-resistant bacteria. Epidemiological studies have focused primarily on two common antimicrobial-resistant organisms—methicillin-resistant Staphylococcus aureas (MRSA) and vancomycin-resistant enterococci (VRE).

"Recently, it has become apparent that multidrug resistance among gram-negative bacteria is becoming an even greater problem in these facilities, with nearly half of long-term care facility residents harboring multidrug-resistant gram-negative bacteria," write the researchers, led by IFAR's Erin'O'Fallon, M.D., M.P.H., in the January issue of the Journal of Gerontology: Medical Sciences.

MDRGN can lead to toxins in the bloodstream that cause and destroy healthy tissue. Left untreated, these infections can be fatal.

More than 80 percent of the MDRGN cases in the study were resistant to commonly prescribed antimicrobial medications, including ciprofloxacin, trimethoprim-sulfamethoxazole, and amipicillin/sulbactam. By definition all of the identified MDRGN bacteria were resistant to at least three different classes of antimicrobial drugs, with one-third of them resistant to four.

These findings, says Dr. O'Fallon, a staff geriatrician at Hebrew Rehabilitation Center and a research fellow in medicine at Harvard Medical School, raise concerns about the therapeutic options available to physicians in treating long-term care residents with MDRGN. Hospitals and long-term care facilities have only recently begun to include MDRGN in their surveillance of antimicrobial-resistant and have extended requirements for contact precautions to MDRGN.

Using more than 1,660 clinical cultures (urine, blood and wound specimens) obtained from residents at a large, urban long-term care facility, the researchers found 180 cases of MDRGN compared to 104 cases of MRSA and 11 cases of VRE. Of further concern, they say, was the steady rise in MDRGN over the two-year study period, which increased from 7 percent the first year to 13 percent in the last year.

Dr. O'Fallon says that infections caused by MDRGN are associated with higher mortality rates, longer hospital stays, and increased costs compared with infections caused by gram-negative bacterial infections that can be treated effectively with antibiotics. Risk factors for MDRGN infection in the long-term care population include pressure ulcers, poor functional status, advanced dementia, and antimicrobial exposure.

Source: Hebrew SeniorLife Institute for Aging Research

Related Stories

Recommended for you

Superbug's spread to Vietnam threatens malaria control

September 21, 2017
A highly drug resistant malaria 'superbug' from western Cambodia is now present in southern Vietnam, leading to alarming failure rates for dihydroartemisinin (DHA)-piperaquine—Vietnam's national first-line malaria treatment, ...

Individualized diets for irritable bowel syndrome better than placebo

September 21, 2017
Patients with irritable bowel syndrome who follow individualized diets based on food sensitivity testing experience fewer symptoms, say Yale researchers. Their study is among the first to provide scientific evidence for this ...

A dose of 'wait-and-see' reduces unnecessary antibiotic use

September 21, 2017
Asking patients to take a 'wait-and-see' approach before having their antibiotic prescriptions filled significantly reduces unnecessary use, a University of Queensland study has shown.

Investigators may unlock mystery of how staph cells dodge the body's immune system

September 21, 2017
For years, medical investigators have tried and failed to develop vaccines for a type of staph bacteria associated with the deadly superbug MRSA. But a new study by Cedars-Sinai investigators shows how staph cells evade the ...

Groundbreaking investigative effort identifies gonorrhea vaccine candidates

September 19, 2017
Researchers at Oregon State University have identified a pair of proteins that show promise as the basis for a gonorrhea vaccine.

Snail fever progression linked to nitric oxide production

September 14, 2017
Bilharzia, caused by a parasitic worm found in freshwater called Schistosoma, infects around 200 million people globally and its advance can lead to death, especially in children in developing countries.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.