Advertisement

Dissecting an outbreak one scope at a time: Is this the new reality?

      Abbreviations:

      HLD (high-level disinfection), MDRO (multidrug-resistant organism)
      The infectious risk of ERCP has historically been ascribed to biliary stasis and obstructive physiology from stones, strictures, or stents. Recent outbreaks, many of them from multidrug-resistant organisms (MDROs), have been attributed to the infectious carriage of the duodenoscope itself: so-called exogenous infection. This has drawn considerable attention and research efforts intended to better characterize the contributory risk of each of the following factors: instrument design, reprocessing measures (eg, manual and automated cleaning), surveillance strategies for detecting instrument contamination, and other quality metrics. What remains clear from various investigations is the failure of current reprocessing Instructions for Use to consistently deliver a pathogen-free instrument. This has resulted in a paradigm shift for centers and physicians who continue to perform necessary procedures using duodenoscopes without an alternative platform, or reliable and verifiable methods for high-level disinfection (HLD) of duodenoscopes. Operators remain hampered by the ill-defined infectious risk apparently innate to the instrument, with limited evidence-based interventions or reprocessing modifications to mitigate such risk.
      In this issue of Gastrointestinal Endoscopy, Rauwers et al
      • Rauwers A.W.
      • Troelstra A.
      • Fluit A.C.
      • et al.
      Independent root-cause analysis of contributing factors, including dismantling of 2 duodenoscopes, to investigate an outbreak of multidrug-resistant Klebsiella pneumoniae.
      report on the investigation after the 2015 outbreak of a strain of multidrug-resistant Klebsiella pneumoniae in patients who underwent ERCP with 2 new-generation Olympus duodenoscopes (TJF-Q180V) at a tertiary center in the Netherlands. By dissecting 1 of the 2 culprit duodenoscopes, the authors aimed to clarify what contributing factors related to duodenoscope design might increase the risk of contamination, with the hypothesis that dismantling contaminated duodenoscopes might inform future reprocessing methods. Previous endoscope dismantling studies in addition to borescopic examinations of duodenoscope working channels identified damages that may increase the risk of contamination and biofilm formation.

      Loeve AJ. Investigational report on a TJF-Q180V duodenoscope following contamination after cleaning and disinfection. Available on request from the Dutch Healthcare Inspectorate/National Institute for Public Health and the Environment (Bilthoven, The Netherlands, 2012).

      • Thaker A.M.
      • Kim S.
      • Sedarat A.
      • et al.
      Inspection of endoscope instrument channels after reprocessing using a prototype borescope.
      • Visrodia K.
      • Petersen B.T.
      Borescope examination: is there value in visual assessment of endoscope channels?.
      The authors report that over 100 “contact patients” were exposed to the contaminated endoscopes, and 27 cases of infection were confirmed by contact screening or laboratory data search. The endoscope dissection included 2 sets of cultures, the first obtained before dismantling from each duodenoscope by use of a systematic sterile sampling method from the suction and working channels, and the endoscope tip plus forceps elevator. An independent expert was commissioned to oversee a site and reprocessing audit and to supervise the dismantling of the 2 culprit endoscopes. Individual parts were cultured once more after dismantling. Three areas for improvement were identified in the reprocessing audit based on discrepancies between the study site’s protocol and the manufacturer’s instructions for use. Damages were found on both endoscopes with the dismantling examination process without any reported malfunction to warrant servicing. This finding is in keeping with other studies,
      • Ross A.S.
      • Baliga C.
      • Verma P.
      • et al.
      A quarantine process for the resolution of duodenoscope-associated transmission of multidrug-resistant Escherichia coli.
      in which outwardly functional endoscopes were found to harbor critical aberrations that potentially predisposed the duodenoscope to contamination. Such findings emphasize the importance of routine servicing regardless of endoscope function or surveillance cultures. The negative cultures before dismantling with the positive cultures after dismantling are a sobering reminder that stringent surveillance cultures have limitations in sensitivity because of the complex design of the duodenoscope, the low bacterial load, or the presence of biofilm, all of which may hinder adequate assessment.
      This study is an illustrative example of one center’s reaction to an outbreak in a multipronged approach: measure A, patient screening (invited screening, retrospective database analysis of culture data based on exposure); measure B, audit of reprocessing by an independent expert; and measure C, dismantling both culprit duodenoscopes. Measure A helped to define the infectivity rate of the contaminated scopes. This has some novelty because reprocessing studies have been focused on abstract measures like HLD defect rate as an outcome measure, but this ultimately is only a surrogate for infectivity. The true infectivity of the device is difficult to measure, and a retrospective analysis of postexposure cultures or infections is fraught with confounding (eg, medical comorbidities, infections with non-MDRO/uniquely identifiable organisms). Measure B identified lapses in reprocessing: communication error, occult instrument damage, inadequate repair. Measure C revealed errant design features that likely increased the risk of contamination (elevator recess, lever, end cap sealing).
      Such a systematic dissection is necessary to fully distill a comprehensive understanding of what factors might snowball into an outbreak. This is a complex phenomenon with a well-matched myriad of factors where error might occur anywhere in the chain of instrument design and malfunction, staff competency and performance, and contamination detection and surveillance. Such an investigation may not be feasible at centers with more limited resources. The question remains: What do smaller or lower-volume centers pursue as recourse? A less-intensive alternative may not fully characterize the breadth and depth of that center’s contamination issues.
      The results of this study, added to the growing body of published literature and postmarket surveillance data
      The FDA Continues to Remind Facilities of the Importance of Following Duodenoscope Reprocessing Instructions: FDA Safety Communication.
      around duodenoscope-associated cross-contamination, underscore the new reality that duodenoscopes cannot be reliably reprocessed with existing cleaning protocols. This, in turn, creates an unquantifiable risk of exogenous bacterial transmission, and infection, to patients. This risk is present wherever duodenoscopes are used in clinical care, without exception. Armed with this new reality, 2 choices become immediately obvious to healthcare facilities and practicing endoscopists: accept the status quo, or advocate for the development of new technologies that help us answer the question, “How do I know this duodenoscope is clean?” Although the former is an easier pathway, it is the latter which, in our opinion, is critical. Without question, this will be more difficult and expensive to achieve; however, improving the safety of ERCP remains in the best interest of the most important stakeholder: the patient.

      Disclosure

      Dr Ross is a consultant for Boston Scientific. The other author disclosed no financial relationships relevant to this publication.

      References

        • Rauwers A.W.
        • Troelstra A.
        • Fluit A.C.
        • et al.
        Independent root-cause analysis of contributing factors, including dismantling of 2 duodenoscopes, to investigate an outbreak of multidrug-resistant Klebsiella pneumoniae.
        Gastrointest Endosc. 2019; 90: 793-804
      1. Loeve AJ. Investigational report on a TJF-Q180V duodenoscope following contamination after cleaning and disinfection. Available on request from the Dutch Healthcare Inspectorate/National Institute for Public Health and the Environment (Bilthoven, The Netherlands, 2012).

        • Thaker A.M.
        • Kim S.
        • Sedarat A.
        • et al.
        Inspection of endoscope instrument channels after reprocessing using a prototype borescope.
        Gastrointest Endosc. 2018; 88: 612-619
        • Visrodia K.
        • Petersen B.T.
        Borescope examination: is there value in visual assessment of endoscope channels?.
        Gastrointest Endosc. 2018; 88: 620-623
        • Ross A.S.
        • Baliga C.
        • Verma P.
        • et al.
        A quarantine process for the resolution of duodenoscope-associated transmission of multidrug-resistant Escherichia coli.
        Gastrointest Endosc. 2015; 82: 477-483
      2. The FDA Continues to Remind Facilities of the Importance of Following Duodenoscope Reprocessing Instructions: FDA Safety Communication.
        (Available at:)

      Linked Article