Endoscopes spreading superbugs
Seattle – Hospitals are discovering that it’s nearly impossible to clean endoscopes blamed for spreading deadly bacteria that have sparked lawsuits from patients and sent device regulators scrambling for a fix.
The Seattle hospital where a fatal, drug-resistant superbug was spread by contaminated scopes is still finding germs on the instruments even after heightening its cleaning procedures, researchers reported last week in a journal article.
Virginia Mason Medical Center redoubled efforts to clean the scopes with “meticulous manual cleaning” last year after it learned of an outbreak that affected 32 patients, including 11 who died. The hospital began taking the devices, known as ERCP endoscopes or duodenoscopes, out of service for 48 hours between procedures and culturing them to check for bacteria. Even with more diligent cleaning, the hospital found that 3 percent of the scopes tested positive for contamination and had to be re-cleaned.
Virginia Mason uses the scopes in about 1,800 procedures a year, according to spokeswoman Gale Robinette. That means that, on average, about one scope a week is still contaminated after cleaning.
If every U.S. hospital had a similar rate, that would mean 15,000 operations a year performed with dirty ERCP endoscopes.
We don’t know how the 3 percent rate at Virginia Mason compares with rates elsewhere, because few others test their scopes after each operation. That approach is part of the “costly and extraordinary measures” Virginia Mason took to reduce the risk of transmission, according to the paper, published online in the journal Infection Control and Hospital Epidemiology.
One model of endoscope associated with the outbreaks, manufactured by Olympus, was on the market for years without being cleared through the Food and Drug Administration’s device oversight process. The agency said that Olympus had issued new cleaning instructions, and the company is expected to ship hospitals a new brush to reach intricate parts of the scope. Olympus did not respond to a request for comment.
The FDA, which regulates medical device makers, suggests taking devices suspected to be linked to patient infections out of service for further cleaning and testing. But neither the agency nor Olympus has instructed hospitals to follow Virginia Mason’s lead and hold all ERCP scopes for testing before they are used in the next procedure.
Under pressure from members of Congress, the FDA released final guidelines for cleaning reusable medical equipment on March 12. At the time, FDA officials downplayed the danger of unclean devices. “Patients and health care providers should know that the risk of acquiring an infection from a reprocessed medical device is low,” William Maisel, chief scientist at the agency’s Center for Devices and Radiological Health, said in a statement.
The FDA can’t quantify that risk exactly. It says it received 135 reports of possible infections related to the devices in 2013 and 2014, a period when it estimates a million procedures took place. “If you do the math associated with this, even if not all of the [cases] have been reported, overall that comes out to a fairly low number,” FDA Chief Scientist Stephen Ostroff told reporters when the agency announced the new guidelines.
The Centers for Disease Control and Prevention has published protocols for hospitals that want to culture scopes in between operations, but it’s not yet ready to make a “blanket recommendation,” said Todd Weber, chief of the Prevention and Response Branch in CDC’s Division of Healthcare Quality Promotion. “The problem with recommending it to everybody at all times is that this hasn’t been used outside the outbreak setting very much,” he said.
“We’d like to get more experience and information from real-world setting use,” Weber said. The more hospitals that voluntarily culture scopes and share their data with health authorities, “the sooner we’re going to know how useful this is,” he said. Testing scopes for pathogens regularly, if not in between uses, is already routine in some other countries, including Australia.
The FDA said it encourages hospitals “to evaluate whether they have the expertise, training, and resources to implement the CDC’s recommended surveillance protocol” but recognizes that it “may pose challenges in some settings,” spokeswoman Jennifer Dooren said.
The FDA warned in February that the devices may not be possible to clean fully. That alert came the day after another outbreak, at UCLA Medical Center, made headlines. Other cases tied to the scopes have since come to light in Florida, Philadelphia, Hartford, and another hospital in LA.
Now, Virginia Mason’s investigation offers a new data point, that even with rigorous cleaning 3 percent of its scopes remain contaminated. “We suspect endoscope-associated transmission of pathogenic bacteria might be both more common than recognized and not adequately prevented by current endoscope reprocessing guidelines,” researchers from the Centers for Disease Control, the hospital, and local public health authorities wrote in the new paper.