The bacteria, a strain of Escherichia coli, has genetic changes that make it resistant to an antibiotic used as a “last ditch effort” drug called Colistin. Although this particular antibiotic-resistant strain of E. coli has been seen in China and Europe, the case here is a first for the U.S., reports NBC News.
The strain of E. coli was identified in the urine of a 49-year-old Pennsylvania woman suffering from a urinary tract infection last month by a team of researchers at Walter Reed Army Institute for Research. They submitted a study that was published Thursday in Antimicrobial Agents and Chemotherapy, a publication of the American Society for Microbiology.
What the researchers found was the same MCR-1 gene discovered in November last year. At that time, it had been found in China and has since spread to Asia and Europe. The gene on the E. coli bacteria is called MCR-1. The MCR-1 mutation had spread to E. coli strain SHP45, Klebsiella pneumoniae strains, and Pseudomonas aeruginosa.
“It basically shows us that the end of the road isn’t very far away for antibiotics — that we may be in a situation where we have patients in our intensive care units, or patients getting urinary tract infections for which we do not have antibiotics,” CDC Director Tom Frieden said in an interview Thursday, according to WTVR News.
The authors wrote that the discovery “heralds the emergence of a truly pan-drug resistant bacteria.” They are actually echoing remarks made in November when a study by researchers in China and the UK described a gene found in bacteria that makes them resistant to “last ditch effort” antibiotics.
Colistin – The antibiotic of last resort and MCR-1
The antibiotic Colistin is reserved for particularly dangerous pathogens, including a family of bacteria known as carbapenem-resistant Enterobacteriaceae, or CRE. CRE has been dubbed the “nightmare bacteria.” When the time comes that we start encountering superbugs that are resistant to Colistin, we might hear doctors saying, “Sorry, there is nothing I can do to cure your infection.”
There have been a few bacterias that have become resistant to a number of antibiotics, but quite often this was found to be the result of a mutation in a single organism. This latest finding is much more worrisome because the mutation has arisen in a way that allows it to be easily shared with other bacteria.
“The transfer rate of this resistance gene is ridiculously high, and that doesn’t look good,” said Prof Mark Wilcox, from Leeds Teaching Hospitals NHS Trust in November’s Digital Journal article on the MCR-1 gene.
There is a very real fear with health officials that the E. coli with the MCR-1 mutation could pass it to another superbug that might have other mutations, creating a monstrously dangerous superbug. If this happens, “It is the end of the road for antibiotics unless we act urgently,” Dr. Frieden said.
