Contaminated exam tools were to blame for an alarming outbreak of a drug-resistant superbug in Illinois last year, government health officials reported Thursday.
Endoscopes that use cameras attached to long tubes to snake through the gut, examining the liver, bile ducts and pancreas, weren’t properly disinfected and wound up infecting patients with a particularly dangerous type of CRE, or carbapenem-resistant Enterobacteriaceae, a family of germs highly resistant to antibiotics.
These were rare NDM, or New Delhi metallo-beta-lactamase, CRE cases, which produce an enzyme that renders most antibiotics useless, officials with the Centers for Disease Control and Prevention said. When that happens, it can be difficult or impossible to treat life-threatening infections, experts say.
A CDC team looked at nine cases of NDM CRE in northeastern Illinois that occurred from March to July, including eight at a single hospital.
Health officials were worried that such cases have jumped sharply since 2009, when they were first reported in the U.S. From 2009 through 2012, 27 patients with NDM-producing CRE were confirmed by the CDC. But last year, there were 69 cases in the U.S., including 44 from northeastern Illinois alone, said Dr. Alex Kallen, a CDC outbreak expert.
“It was a little bit of a surprise,” he said.
Even more surprising was that the germs were eventually traced to patients who had a history of endoscopic liver and pancreas exams — and then to dirty tools.
It turns out that the endoscopes, which had undergone high-level disinfection, still tested positive for the dangerous germs. Health officials are not sure why the tools stayed dirty even though proper cleaning procedures were followed.
Officials are urging hospitals to make sure they’re following proper protocol for cleaning tools. In the meantime, the Illinois hospital switched to a new sterilization procedure; no new cases have been reported since.