A series of fatal superbug outbreaks has left the users of duodenoscopes the flexible, side-viewing, upper GI endoscopes implicated in cross-contaminating patients at a difficult crossroads. What are your options when an irreplaceable tool that's seemingly impossible to fully clean harbors an antibiotic-resistant bacteria?
"We will not tolerate infections transmitted by the devices we use. Even though the number is low, it is not one we can allow," says Michael L. Kochman, MD, FACP, the chair of the American Gastroenterological Association's Center for GI Innovation and Technology and a professor of medicine at the University of Pennsylvania's Perelman School of Medicine in Philadelphia. However, he concedes, "We have limited short-term options to put in place to protect our patients."
An outbreak goes public
Between October 3, 2014, and January 28 of this year, 2 patients who'd undergone endoscopic retrograde cholangiopancreatography (ERCP) at UCLA's Ronald Reagan Medical Center in Los Angeles died as a result of carbapenem-resistant Enterobacteriaceae (CRE) infections they'd acquired from contaminated duodenoscopes. At least 7 other patients were infected, hospital officials announced on February 18, and 179 more were notified that they may have been exposed to the bacteria.
What stunned UCLA and government epidemiologists was that the outbreak wasn't caused by shoddy scope reprocessing. "UCLA followed both national guidelines and the sterilization standards stipulated by Olympus Medical Systems Group, the instrument's manufacturer," hospital officials wrote in a public statement (tinyurl.com/lgtgnmn). "After discussion with local and national public health officials, it appears that the ERCP scopes will require additional cleaning techniques beyond what is recommended by the manufacturer or significant redesign of parts of the scope."
For its part, the hospital now touts "one of the most stringent scope protocols in the United States," not only manually cleaning and high-level disinfecting the scopes in an automated endoscope reprocessor, but also shipping them off site for ethylene oxide (EtO) gas sterilization. It hasn't seen any new CRE cases since implementing this protocol, according to the Los Angeles Times.
Tip of the iceberg
Several other hospitals have reached this conclusion after suffering outbreaks of their own. It was reported in January that properly reprocessed, yet CRE-contaminated duodenoscopes may have contributed to the deaths of 11 patients and the sickening of 32 others at Virginia Mason Medical Center in Seattle between 2012 and 2014. The hospital now cultures and quarantines reprocessed scopes for 48 hours, then checks them for bacterial growth. Because this lengthens the time it takes to return a scope to the OR, the hospital has purchased 20 new scopes.
In the October 2014 issue of JAMA, researchers who'd investigated a 2013 outbreak at Advocate Lutheran General Hospital in suburban Chicago explained that EtO sterilization is the surest method of preventing the transmission of multi-drug resistant organisms via difficult-to-disinfect duodenoscopes (tinyurl.com/ljeug8a). The same month, researchers from UPMC Presbyterian in Pittsburgh, reflecting on a 2012 outbreak, presented similar findings at an epidemiology conference (tinyurl.com/qxj985j). Like UCLA, neither hospital has seen a scope-driven CRE case since adopting the EtO sterilization techniques.
The inability of standard, manufacturer-mandated reprocessing practices to eliminate dangerous bacteria from the complex inner workings of the duodenoscope has been a concern to some infection prevention and GI professionals for decades.
"Historically, 1 in 1.8 million of all endoscopic procedures present a cross-contamination risk or result in patient infection," says Charles Edmiston Jr., PhD, CIC, emeritus professor of surgery at the Medical College of Wisconsin in Milwaukee and director of its Surgical Microbiology Research Laboratory. "We've always suspected these infections occurred at a much greater frequency with duodenoscopes."
Some CRE outbreaks may even go unrecognized, says Dr. Edmiston, who co-authored an examination of the infection risks in scope reprocessing for the December 2014 AORN Journal, since the causes of infection in critically ill patients may be attributed to other factors and the majority of non-critically-ill patients may wind up colonized but not infected by the bug. "As with Ebola, this is going to be an evolving topic," he says.
What's more, the U.S. Food and Drug Administration has been aware of the hazards that duodenoscopes may present for more than 2 years, although it wasn't until after UCLA reported its outbreak that the agency spoke up on the matter.
In a safety communication, FDA officials noted that they had received 75 reports involving 135 patients of possible cross-contamination from reprocessed scopes between January 2013 and December 2014 (tinyurl.com/mrjo4g6).
A further alert warns, "Some parts of the scopes may be extremely difficult to access and effective cleaning of all areas of the duodenoscope may not be possible," adding that "a recent FDA engineering assessment and a growing body of literature have identified design issues in duodenoscopes that complicate reprocessing of these devices." (tinyurl.com/n42nf7c)
At issue is a movable "elevator" mechanism at the tip that flexes the angle of catheters or other accessories threaded through the device's channels. Unique to duodenoscopes, it has microscopic crevices that standard brushes can't scour. Bacteria can build up in these crevices. "Meticulously cleaning duodenoscopes prior to high-level disinfection should reduce the risk of transmitting infection, but may not entirely eliminate it," states the FDA.
Strains of CRE, which includes Klebsiella and E. coli, naturally and harmlessly inhabit the colon but spark an antibiotic-resistant infection when spread to other parts of the body, as by a scope inserted down the throat, through the stomach and into the small intestine.
Despite its awareness of the hazard, the FDA has not ordered a recall of duodenoscopes, largely because no other device can do what they do in the estimated 500,000 ERCP procedures performed in the United States each year. "The procedure is the least invasive way of draining fluids from pancreatic and biliary ducts blocked by cancerous tumors, gallstones or other conditions," says the agency, adding that "the continued availability of these devices is in the best interest of the public health" and outweighs the potential risks.
Course of action
Lawmakers and safety advocates are criticizing the FDA and duodenoscope manufacturers for failing to sufficiently protect patients. Greater government oversight and a slew of lawsuits are inevitable. (In the first lawsuit stemming from the superbug outbreak at UCLA, an 18-year-old patient accused Olympus of negligence for selling a medical scope prone to spreading deadly bacteria.) But in the meantime, what's the best course of action for a facility that hosts ERCPs?
The recommendations in the FDA's safety communication don't advise a radical change in practices. Scope reprocessors should strictly adhere to manufacturers' instructions, paying meticulous attention to the elevator. The "Multisociety Guideline on Reprocessing Flexible Gastrointestinal Endoscopes," published in the journal Gastrointestinal Endoscopy in 2011, offers solid guidance (tinyurl.com/amuzlh5). Providers should be able to explain the benefits and risks of ERCP and the warning symptoms of CRE infections, as well as why patients undergoing other procedures are not at risk.
"Ethylene oxide seems to be the best short-term option we have, to ensure complete sterilization," says Dr. Kochman, although it presents a few difficulties. It sidelines your scopes for a couple of days, which means you may have to acquire more of them at about $50,000 per device. Because the method presents an environmental and occupational hazard, many facilities do not have ethylene oxide on site. Plus, any gas residue remaining in the scope can harm patient tissue, says the FDA, which does not recommend routine EtO sterilization. Olympus, the manufacturer of UCLA's scopes, says that its duodenoscope is compatible with EtO (tinyurl.com/njqk94h).
On the other hand, "long-term solutions will require a redesign of the devices," says Dr. Kochman, as the often-overlooked process of instrument reprocessing becomes a regulatory hot-button issue.
FDA officials say they intend to seek and review evidence for the effectiveness of scope manufacturers' recommended cleaning and disinfection practices, something the agency admits it has not previously given sustained scrutiny, and will hold the makers of new devices to higher standards with regard to reliable reprocessing. In letters to customers, the leading manufacturers of duodenoscopes Olympus (tinyurl.com/nkagd4x), Pentax (tinyurl.com/ovlr9y5) and Fujifilm (tinyurl.com/nra8tnu) pledge cooperation with the FDA and other stakeholders.
That cooperation is a welcome step, says Mary Logan, JD, CAE, president of the Association for the Advancement of Medical Instrumentation, which is expecting to finalize ST-91, its new standard for reprocessing flexible endoscopes, in 2 months. "This isn't going to be solved overnight. There is no silver bullet here. And it's not going to be solved by pointing fingers at hospitals or the FDA or manufacturers," she says.
Safer scopes will be a function of better design, standardized equipment and instructions, trained and certified reprocessors, policies that allow them the time to complete their responsibilities, protocols that include process testing and documentation and a continued eye on standards, surveys and warnings. "It's going to take all these things in tandem to get better," says Ms. Logan.