WASHINGTON -- Hospitals and gastrointestinal endoscopy clinics should make plans to stop using duodenoscopes with fixed endcaps, switching instead to products with single-use parts, the -- as a first step toward entirely disposable duodenoscopes.
The agency noted that it has now cleared two duodenoscopes with disposable endcap components -- Fujifilm's model ED-580XT and the Pentax model ED34-i10T.
It's the FDA's latest move to cut infections arising from incompletely sterilized duodenoscopes used in endoscopic retrograde cholangiopancreatography (ERCP) procedures. These devices have hinged elevator mechanisms at the tip, which are thoroughly. Although the major manufacturers have introduced different designs and beefed up the recommended processes for sterilizing the devices after use, studies continue to show that a small but still concerning proportion test positive for pathogen contamination after reprocessing. And currently available duodenoscopes are too costly to use only once.
Thursday's announcement also included an admission that the reprocessing procedures may simply be too difficult to follow exactly in every case. It noted results of so-called human factor studies that "suggest that users frequently had difficulty understanding and following manufacturers' [instructions] and as a result, were not able to successfully complete reprocessing." Efforts to refine and clarify the cleaning instructions will continue, the agency said.
Nevertheless, "The FDA believes the best solution to reducing the risk of disease transmission by duodenoscopes is through innovative device designs that make reprocessing easier, more effective, or unnecessary," the agency said. "Disposable designs may reduce between-patient duodenoscope contamination by half as compared to reusable, or fixed endcaps."
As before, the FDA does not plan to recall conventional duodenoscopes or recommend other alternatives to ERCP, which is performed on about 500,000 patients annually in the U.S.
The issue broke into the news in February 2015, when it was revealed that multiple patients at a UCLA hospital developed antibiotic-resistant abdominal infections -- two fatal -- stemming from ERCP procedures. The FDA then admitted it had been receiving such reports for at least 2 years without taking action.
Later that year, members of the agency's Gastroenterology and Urology Devices Advisory Committee agreed that then-current duodenoscopes must remain on the market because of the lack of alternatives -- while also voting unanimously that the devices are unsafe.
"We recognize that an immediate transition away from conventional duodenoscopes to the newer, innovative models will take time due to cost and market availability," the agency said Thursday. "We encourage health care facilities purchasing new duodenoscopes to begin developing a transition plan and work to replace their conventional duodenoscopes with newer models."
The agency is also taking other steps to address the duodenoscope contamination problem:
- Asking manufacturers to list "real-world contamination rates" in labeling of fixed-endcap devices
- Requiring post-market surveillance studies by manufacturers of the newer products with disposable components
- Encouraging development of novel sterilization methods
- Holding an advisory committee meeting later this year to discuss current efforts to address the problem
One thing the FDA is urging hospitals and clinics not to do is use adenosine triphosphate (ATP) test strips to monitor for contamination. Live organisms shed ATP and, in theory, its detection should indicate contamination. Some vendors have begun marketing ATP test strips for this purpose. But the FDA said these test strips have not been evaluated or cleared for such use, and it has issued notices to their manufacturers.
Ultimately, the FDA said, it hopes that "fully disposable duodenoscopes" will render the contamination problem moot.