Healthcare Hygiene magazine December 2019 | Page 33

In December 2018, the agency released an alert about
rates of duodenoscope contamination from scope manufac-
turers’ preliminary post-market data. At the time, the FDA’s
Shuren reported on the U.S. duodenoscope manufacturers’
study examining the sampling and culturing of reprocessed
duodenoscopes that are in clinical use to characterize
contamination rates and to learn more about issues that
contribute to contamination, as well as another study to
assess how effectively hospital staff follow the manufacturers’
reprocessing instructions.
As Shuren stated last year, “Interim results from the
sampling studies indicate higher-than-expected contamination
rates after reprocessing, with up to 3 percent of properly
collected samples testing positive for more than 100 colony
forming units of low concern organisms that are unlikely to
cause serious infections (but an indication of a reprocessing
failure) and an additional 3 percent of properly collected
samples testing positive for ‘high-concern’ organisms. These
are bacteria more often associated with disease, such as E.
coli or Staphylococcus aureus.”
Some factors that may have contributed to device con-
tamination include device damage and errors in reprocessing.
Shuren said that healthcare facilities that use duodenoscopes
should meticulously follow manufacturers’ reprocessing
instructions. In addition, healthcare facilities should consider
implementing supplemental reprocessing measures to reduce
the risk of infection transmission, such as microbiological
culturing, sterilization, use of a liquid chemical sterilant
processing system and repeat high-level disinfection.
At the November hearings, the FDA’s Haugen reported
that a recent survey found widespread implementation of
supplemental measures to enhance duodenoscope reprocess-
ing. Thaker (2018) reported that of 249 healthcare facilities,
90 percent implement one or more supplemental measures:
 Repeat manual cleaning and HLD: 63%
 Surveillance microbiological culturing: 53%
 Liquid chemical sterilization: 35%
 EtO gas sterilization: 12%
Haugen noted that results of the sampling/culturing
post-market surveillance study are consistent with published
reports (Bartles 2018, Rauwers 2018, Ross 2015, Rex 2018,
Snyder 2017, Visrodia 2017) that found some percentage of
duodenoscopes remain contaminated after use. Additionally,
repeat HLD does not significantly impact the contamination
rate compared to single HLD (Bartles 2018, Snyder 2017).
Further, Haugen explained the literature shows that:
 Contamination rates after EO sterilization are variable
(Naryzhny 2016, Snyder 2017)
 Ethylene oxide sterilization of duodenoscopes led to cessa-
tion of outbreaks (Epstein 2015, Smith 2015, Humphries 2017)
 Additional sterilization technologies are in development
for duodenoscopes (Molloy-Simard 2019)
The FDA also recommended that hospital staff carefully
inspect a component of the duodenoscope that is difficult to
clean, called the elevator recess, and to repeat cleaning if any
soil or debris is visible: “We are also emphasizing that users
follow the manufacturer’s recommendations for inspection,
leak testing and maintenance of the duodenoscope and return
the duodenoscope to the manufacturer, at least once a year,
for inspection, servicing and maintenance.”
www.healthcarehygienemagazine.com • december 2019
The FDA also encouraged healthcare providers to participate
in the manufacturers’ sampling and culturing studies and
consider initiating their own duodenoscope surveillance
sampling and culturing to reduce the risks of infection.
However, Shuren added, “It has become clear that
following the manufacturer’s reprocessing and maintenance
instructions, while critical, is not sufficient to avoid all infections
associated with the use of duodenoscopes. That is why the
FDA has also been working with developers on new product
designs, including disposable components. Technological
advances in product design hold promise to reduce the risk
of contamination and enhance patient safety.”
The results of these manufacturers post-market surveillance
studies suggest that users frequently had difficulty understand-
ing and following manufacturers’ instructions for use (IFUs)
and were not able to successfully complete reprocessing,
which may leave the duodenoscopes contaminated. The
FDA says it continues to work with manufacturers to conduct
additional testing and revise reprocessing instruction manuals,
as appropriate.
At the November hearings, the FDA’s Shani Haugen noted,
“A contaminated duodenoscope indicates a failure somewhere
in the reprocessing procedure and raises the risk of infection
for patients, but it is unknown how the percentage of
contaminated duodenoscopes relates to patient infections.”
Haugen pointed to the fact that the manufacturers, in
their post-market surveillance studies, found that between 4
percent and 6 percent of duodenoscopes were contaminated.
“While not every exposure leads to infection, these rates
are concerning to the FDA,” she emphasized at the November
hearings. “These rates tell us that improvements are necessary.
The FDA is committed to taking additional steps to reduce
contamination and infections even further.”
The FDA says the best path to reducing the risk of disease
transmission by duodenoscopes is through innovative device
designs, such as those with disposable components, that make
reprocessing easier, more effective or unnecessary.
Fixed endcap duodenoscopes have a plastic or rubber cap
permanently glued to the metal edges around the distal end
to prevent tissue injury from the metal edges on the scopes,
but when permanently affixed, the endcaps also limit the
accessibility to clean the crevices at the distal end. The FDA is
recommending healthcare facilities transition away from fixed
endcap models including Olympus Corporation’s TJF-Q160,
TJF-Q180V, PJF-160 and JF-140F; Fujifilm Medical Systems
USA’s ED-530XT; and Pentax Medical’s ED-3490TK. The FDA
has cleared two duodenoscopes with disposable end caps:
Fujifilm Corporation, model ED-580XT and Pentax Medical,
model ED34-i10T. Additionally, other firms have publicly
announced plans to develop fully disposable duodenoscopes.
As we have seen, the FDA previously required post-market
surveillance studies from each U.S. duodenoscope manufactur-
er (Olympus, Fujifilm and Pentax) to determine the real-world
contamination rates for duodenoscopes and serve as measures
for the effectiveness of reprocessing.
For the continuation of this article, visit: https://
www.healthcarehygienemagazine.com/fda-convenes-
advisory-panel-for-further-understanding-of-the-
duodenoscope-related-infection-risk/
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