January 21, 2015 The University of Pittsburgh Medical Center — also known as “UPMC” — linked a bacterial “superbug” outbreak in 2012 to the inadequate cleaning and disinfection, or “reprocessing,” of contaminated gastrointestinal (GI) endoscopes, according to the hospital officials.

The nightmarish bacteria responsible for this outbreak at UPMC (Pittsburgh, PA) is called carbapenem-resistant Enterobacteriaceae, or “CRE.”

While other similar reports of the transmission of CRE and their related superbugs during GI endoscopy have been documented in the U.S. and globally, this article places attention on UPMC’s outbreak of CRE in 2012.

CRE are so named, because they are resistant to most antibiotics including those of “last resort” called carbapenems. And, whereas other types of bacteria transmitted during GI endoscopy can typically be eradicated with one or more types of antibiotics, some strains of CRE are resistant to all types of antibiotics (i.e., they are pan-resistant).

Pittsburgh, Pennsylvania, 2012

In 2012 an outbreak of CRE in Pittsburgh, Pennsylvania, was linked to the contamination of a type of GI endoscope known as a side-viewing duodenoscope.

Because physicians use it to perform a medical procedure called endoscopic retrograde cholangiopancreatography, or “ERCP,” this GI endoscope may also be referred to as an ERCP endoscope.

Although this hospital’s first infected patient was reportedly identified in 2012, the details of its CRE outbreak were only recently published, approximately two years later.

On October 13, 2014, a Pittsburgh newspaper published the article: “Scope disinfection failure suspected in superbug cluster, leads UPMC to alter methods,” which provides some important details of this CRE outbreak, identifying this hospital as the University of Pittsburgh Medical Center-Presbyterian.

This newspaper article appears to have been published in direct response to a scientific abstract that hospital officials presented two days earlier, on October 11, 2014, at an infectious disease conference in Philadelphia (PA).

Entitled “High Level Disinfection (HLD) Failure in Gastrointestinal Scopes with Elevator Channels: Is it Time to Switch to Ethylene Oxide (ETO) Sterilization?this abstract discusses details about UPMC’s outbreak of CRE that had not been previously known.

For example, not only ERCP endoscopes, but also a second type of GI endoscope known as “EUS” endoscopes poses an increased risk of infections from CRE and their related superbugs.

Whereas ERCP endoscopes are used to examine the GI tract to identify diseases oo-f the liver, bile ducts, and pancreas, EUS echendoscopes are used to examine the lining and walls of the upper (e.g., esophagus) and lower (e.g., colon) GI tract during a procedure known as endoscopic ultrasonography (EUS).

The design of both of these types of GI endoscopes features a forceps elevator mechanism, which reports suggest may be difficult to clean, posing an increased risk of disease transmission. According to the federal Centers for Disease Control and Prevention, or CDC, “the design of the ERCP endoscopes might pose a particular challenge for cleaning and disinfection.”

The cause of UPMC’s CRE outbreak in 2012, like that of other reported outbreaks of this same superbug documented in the U.S. during the past 6 years, appears to be inadequate reprocessing of these two types of implicated GI endoscopes.

Namely, these causes of these several CRE outbreaks are reportedly are result of:

  • their complex physical design and forceps elevator mechanism (as the CDC has published);
  • a shortcoming in the manufacturer’s reprocessing instructions;
  • one or more breaches in the execution of these instructions and reprocessing steps — for example, the use of contaminated rinse water, inadequate cleaning or insufficient drying of the GI endoscope, or the use of an improperly serviced and maintained GI endoscope; and/or
  • a confluence of all four of these factors.

UPMC’s outbreak of CRE reportedly stopped once it began using ethylene oxide (EtO) gas to sterilize its GI endoscopes (in lieu of high-level disinfection).

More about this CRE outbreak in Pittsburgh (PA), 2012

The abstract that UPMC officials presented in Philadelphia (PA) in October, 2014, is not the only one that this hospital published discussing its CRE outbreak in 2012.

UPMC officials wrote a second abstract about this outbreak entitled, “Carbapenem-resistant Enterobacteriaceae (CRE) Klebsiella pneumonia (KP) Cluster Analysis Associated with GI Scopes with Elevator Channel.”

Anything but unique

Although some news reports have incorrectly stated otherwise, CRE outbreaks such as UPMC’s in 2012 are anything but isolated and unique. (Read the related article: “Response to a News Report about a ‘Superbug’ Outbreak at a Hospital in Illinois, 2013.”)

For example, one year later, in 2013, the CDC investigated an outbreak of CRE remarkably similar to UPMC’s outbreak, one that was also linked to ERCP, this time at a hospital near Chicago (IL). At the time, the press labeled this the largest CRE outbreak in U.S. history, and it still may be.

The CDC published the result of its investigation of this CRE outbreak in the Journal of the American Medical Association (JAMA) — click here to read: “New Delhi metallo-β-lactamase-producing carbapenem-resistant Escherichia coli associated with exposure to duodenoscopes.”

The local media in Illinois publicized this CRE outbreak in January, 2014, identifying the hospital by name: Advocate Lutheran General Hospital — click here to read: “Lutheran General upgrades scope cleaning after ‘superbug’ outbreak” (January 3, 2014).

Other CRE outbreaks linked to GI endoscopy: Washington, 2012

The Food and Drug Administration’s (FDA) MAUDE database lists a number of other outbreaks of CRE — and their related superbugs including carbapenem-resistant Pseudomonas aeruginosa and ESBL-producing E. coli— following GI endoscopy.

“MAUDE” is an acronym for the FDA’s Manufacturer and User Facility Device Experience database, which lists medical device reports, or MDRs, filed by hospitals and medical device manufacturers upon learning of an adverse event linked to a medical device.

One of these reports filed in the FDA’s MAUDE database in the summer of 2014 documents a CRE outbreak, with associated morbidity and mortality, in Washington state two years earlier, in 2012.

This recent outbreak of CRE in Washington state may be the most significant instance of disease transmission, certainly in terms of the number of associated patient deaths, ever linked to a GI endoscopic procedure, not just in the U.S., but worldwide. — Lawrence F Muscarella PhD

Yet, little about this Washington hospital’s CRE outbreak in 2012 has been publicly mentioned. The first time it received public attention was when Dr. Muscarella published on December 24, 2014, the article: “7 More Deaths Linked to GI Endoscopes in Washington: Part of a National Epidemic?” — click here.

This CRE outbreak is also discussed by an official of the department of Public Health-Seattle & King County in Seattle (WA), if abstractly, in the presentation entitled “Endoscope-Associated Multidrug-Resistant Escherichia coli Outbreak — King County, Washington, 2012–2014″ — click here.

This presentation suggests that this hospital in Washington where this superbug outbreak was identified was Virgina Mason Medical Center (Seattle, WA).

And, if the CRE outbreak at Advocate Lutheran General Hospital in 2013 is not the largest of its type ever recorded in U.S. history (as the press has reported), this one in Washington certainly is.

Is a FDA health notice forthcoming?

The FDA is reputed to be issuing soon a public health notice informing the public of the risk of CRE infection during GI endoscopy, in response to these CRE outbreaks identified in Pennsylvania, Washington, and Illinois, as well as several other superbug outbreaks that have been documented in the U.S. since 2008.

Investigations of each of these superbug outbreaks linked contaminated GI endoscopes to disease transmission.

And, while the risk has been shown to be significant, these reported outbreaks of CRE appear to under-estimate the true risk of infection during GI endoscopy significantly, as unpublished data reveal that a number of CRE outbreaks recently occurring in the U.S. have not been publicly acknowledged and, therefore, their infections have not been counted or tabulated.

To be certain, CRE can be associated with a mortality rate of as high as 50%. In fact, seven (7) of the 14 CRE-infected patients who underwent ERCP in 2012 at the aforementioned hospital in Washington state reportedly died.

Although infrequently, the FDA has previously released public health advisories alerting the public to the risk of infection associated with the faulty reprocessing of GI endoscopes. The growing number of reports of ‘superbug’ infections and deaths linked to contaminated GI endoscopes argues for the prompt release of another advisory. — Lawrence F Muscarella, PhD

The possibility of a forthcoming FDA advisory is discussed in more detail in the related article “Superbugs, Contaminated Gastrointestinal Endoscopes, and a Growing Number of Hospital Infections: Is an FDA Action Imminent?” — click here.

Moreover, a list of important lessons that these recent CRE outbreaks are teaching hospitals and that warrant attention and prompt action is provided in another related article entitled, “Important Lessons Taught by Recent ‘Superbug’ Outbreaks Linked to GI Endoscopes” — click here.

Legal Reviews for Patients, Hospitals, Manufacturers:  Click here to read about Dr. Muscarella’s expertise and legal assessments of the causes of healthcare-associated infections, including “superbug” outbreaks linked to contaminated GI endoscopes and other reusable medical equipment.

Note about ethylene oxide (EtO) gas sterilization

While its contents are, of course, unknown at this time, the FDA’s forthcoming health advisory may suggest that hospitals consider using EtO gas (if it’s available, and at least for the time being) to “sterilize” GI endoscopes, in addition to manually cleaning their complex surfaces with a brush.

This recommendation appears to be evidence-based: For each of these three document CRE outbreaks in Pennsylvania, Illinois and Washington, the hospital’s use of EtO gas sterilization was reported to stop further instances of infection.

EtO gas sterilization used for this purpose is somewhat controversial, however, and will come with a price. Many hospitals do not use an EtO gas sterilizer.

And, for those that might, the instrument processing time of EtO gas sterilizers can be as long as 24 hours, necessarily requiring that the hospital purchase additional GI endoscopes to meet patient demand … at a cost that could exceed $1,000,000 for a busy endoscopy unit.

The use of EtO gas sterilization to process ERCP endoscopes might require that busy endoscopy units purchase hundreds of thousands of dollars of additional endoscopic equipment, if not more, to meet patient demand and to ensure that the GI endoscopes are not contaminated with CRE. — Lawrence F Muscarella PhD

Noteworthy, no EtO gas sterilization process has been cleared by the FDA for processing GI endoscopes, the FDA’s likely forthcoming recommendation to consider using it notwithstanding.

Other FDA alerts

The incidence of CRE transmissions during GI endoscopy is increasing.

During similar type of circumstances, the FDA has previously released health advisories discussing the faulty reprocessing of GI endoscopes, although these types of reports issued by the FDA are infrequent.

These alerts include:

  • Preventing Cross-Contamination in Endoscope Processing Safety Communication from FDA, CDC, and the VA (Issued: November 19, 2009) — click here; and
  • FDA and CDC Public Health Advisory: Infections from Endoscopes Inadequately Reprocessed by an Automated Endoscope Reprocessing System (September 10, 1999) — click here.


A number of recommendations for the prevention of CRE transmissions during GI endoscopy are provided in his related article entitled, “Investigation and Prevention of Bacterial Outbreaks following Endoscopic Retrograde Cholangiopancreatography, or ERCP” — click here.

Recommendations are also provided in the peer-reviewed article entitled, “Risk of transmission of carbapenem-resistant Enterobacteriaceae and related “superbugs” during gastrointestinal endoscopy” — click here (refer to this article’s Table 4).

Closing remarks

Among others, the Department of Public Health-Seattle & King County (click here) in Seattle (WA) and officials of UPMC (click here) suggest that current recommendations for reprocessing ERCP endoscopes (and EUS endoscopes) are inadequate and warrant reevaluation.

It could be, however, that, if the endoscope manufacturers were to enhance future designs of these types of GI endoscopes, especially the design of their forceps elevator mechanism, to facilitate its more effective cleaning and disinfection, then the revision of such reprocessing guidelines to recommend the sterilization of these endoscopes (in lieu of high-level disinfection), not only could cost hospitals millions of dollars (e.g., as required to purchase additional equipment, but might become unnecessary.

Additional reading

Featured in his blog (“Discussions in Infection Control“) is a codified list of several of Dr. Muscarella’s related articles that discuss this increased risk of CRE infection associated with contaminated GI endoscopes, both in the U.S. and globally — click here.

Included in this list are the following articles:

  • Alert: Association of GI Endoscopy with Two Patient Deaths: Illinois, 2013” — click here.
  • Overlooked Outbreaks of “CRE” Following GI Endoscopy: A ‘Superbug’ Epidemic in Our Midst?” (which was posted a year ago, in 2013) — click here.
  • “Lessons Taught by a Recent “Superbug” Outbreak: Could Ex Post Facto Notification be Warranted?”click here.
  • “Investigation and Prevention of Bacterial Outbreaks during Endoscopic Retrograde Cholangiopancreatography (or, ERCP)”click here.

Article by: Lawrence F Muscarella, PhD; posted: 1/21/2015, Rev B

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