Fighting Superbugs
Drug-resistant "superbugs" are multiplying, causing infections that are unable to be treated with our normal arsenal of antibiotics.
A recent example: the September case of Klebsiella pneumonia that killed a Nevada woman after resisting a total of 26 different antimicrobial drugs.
Antibiotic-resistant infections, including Gram-negative bacteria, C. difficile, and S. aureus (MRSA), kill 23,000 people in the United States each year and sicken many others.
As an academic health center, we carefully monitor these dangerous infections. The clinical microbiology laboratory at Emory University Hospital, directed by pathologist Eileen Burd, examines more than 800 cultures a day to determine which bacteria are making patients sick and how best to treat them.
Let me share how just one of these cases led to an important discovery.
In the fall of 2013, Burd and her team noticed something strange in a sample taken from a kidney transplant patient. A strain of Gram-negative baccilli, E. cloacae, had infected the patient and was proving resistant to most of the usual antibiotics, so the team tried a "last-ditch" drug, colistin. At first, colistin appeared to work, killing off most of the bacteria. On closer inspection, though, it seemed that a small number had survived.
Microbiologist David Weiss, head of the Emory Antibiotic Resistance Center (ARC), was called in to consult. He found that the bacteria had mounted "stealth" resistance — a small colony, which normally would have gone undetected, remained. Even more troubling, these survivors appeared to expand in the presence of colistin. Weiss is now studying these "persisters."
Collaboration between front-line patient care teams and laboratory scientists led to this fortuitous discovery. Due to such alliances, and the ARC (whose researchers can be seen on pages 14 to 23), Emory has emerged as a leader in the battle against superbugs and antibiotic resistance. This is a fight we must win.
