May 27, 2016
1 min read

Colistin resistance detected in US patient for first time

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Colistin resistance has been detected in a patient in the United States for the first time, further magnifying fears over antibiotic resistance.

The discovery was made by Defense Department researchers who recently began looking for resistance to the last-resort antibiotic in specimens submitted to the clinical microbiology laboratory at Walter Reed National Military Medical Center.

They detected the colistin-resistant mcr-1 gene in an Escherichia coli culture taken from a female patient with a urinary tract infection.

Thomas Frieden

Thomas R. Frieden

CDC Director Thomas R. Frieden, MD, MPH, announced the finding during an address at the National Press Club and warned that better stewardship was needed to fight antibiotic resistance.

“The medicine cabinet is empty for some patients,” Frieden said. “It is the end of the road for antibiotics unless we act urgently.”

The specimen came from a woman who sought treatment at a Pennsylvania clinic in April. The woman, aged 49 years, reported no travel within the previous 5 months, according to Patrick McGann, PhD, microbiologist at Walter Reed, and colleagues, who published their findings in Antimicrobial Agents and Chemotherapy.

“To the best of our knowledge,” they wrote, “this is the first report of mcr-1 in the United States.”

The E. coli cultured from the woman’s urine, MRSN 388634, was forwarded to the lab at Walter Reed, where researchers began testing for resistance to colistin in response to the discovery of mcr-1, which they called a “truly pan-drug resistant bacteria.”

MRSN 388634 belongs to a rare E. coli sequence type that was first identified in 2008 from a urine culture in the United Kingdom and later identified from a bloodstream culture in Italy, McGann and colleagues wrote. They warned that they were in the early stages of testing and that continued surveillance was needed to determine the true prevalence of mcr-1 in the population.

“The more we look, the more we’ll find,” Frieden said. “The more we look at drug resistance, the more concerned we are. We need to do a very comprehensive job so we can have [antibiotics] and our children can have them. We can make new ones, but without better stewardship and identification of outbreaks, we’ll lose these miracle drugs.” – by Gerard Gallagher

Disclosure: The researchers report no relevant financial disclosures.