A medical device tied to deadly bacterial infections continues to contain high pathogen levels even after rigorous sanitization protocols are followed, according to the US Food & Drug Administration. In an April 12, 2019 Safety Communication, FDA experts again rang alarm bells over the duodenoscope, a reusable medical device found to transmit bacterial pathogens from one patient to another. Despite a renewed focus on device sanitization, up to 5.4% of sampled duodenoscopes show signs of contamination with “high concern organisms.”

FDA Warns Of Duodenoscope Contamination Rates

Duodenoscopes are narrow, tubal medical devices used by physicians to photograph and film within the small intestine. Outfitted with various attachments, the scopes can also be utilized to release blockages of occluded ducts and drain fluid buildup. But tragically, the medical devices have also been linked to a series of virulent bacterial outbreaks. As we now know, duodenoscopes can transmit bacterial pathogens from one patient to another, in part due to their idiosyncratic design, which makes the reusable scopes extremely difficult to clean.

Microscope In Laboratory

“Duodenoscopes are complex instruments that contain many small working parts,” the FDA reports. “If reprocessing instructions are not followed in every step of the process, tissue or fluid from one patient can remain in a duodenoscope when it is used on a subsequent patient. In rare cases, this can lead to patient-to-patient transmission of infection.”

Adequate Sanitization Protocol Evades Experts

Expert advisers at the US Food & Drug Administration have struggled to develop an adequate sanitization protocol for duodenoscopes since at least 2013. In hopes of establishing a rigorous protocol, the FDA ordered three duodonescope manufacturers – Fujifilm, Olympus and Pentax – to conduct a series of postmarket surveillance studies on how duodenoscope sanitization regimens are followed in real-world settings. While data collection is ongoing, the preliminary results of these reports are not promising.

“Higher Than Expected” Contamination Rates

“The preliminary results as of March 2019 indicate higher than expected levels of contamination,” the FDA reports. As the FDA explained, manufacturers were ordered to contribute data to what is being called the Sampling and Culturing Study. This study “was designed to evaluate the percentage of clinically used duodenoscopes which remain contaminated with viable microorganisms after use of labeled reprocessing instructions.” In designing the study, experts assumed a contamination rate lower than 0.4%. As it turns out, the real-world contamination rates appear to be far higher:

  • “for low to moderate concern organisms with >100 CFU, updated culturing results continue to indicate a higher-than-expected contamination rate after reprocessing, with up to 3.6% of properly collected samples testing positive.
  • for high concern organisms, defined as organisms that are more often associated with disease, such as E. coli, and Pseudomonas aeruginosa, updated culturing results appear to show that up to 5.4% of properly collected samples test positive, which is an increase from the 3% contamination rate that was previously reported.”

FDA reviewers are still working to determine why these contamination rates are so high. In its Safety Communication, the agency suggests device damage and errors in reprocessing as possible causal factors.

Infection Rates Fall, But Concerns Persist

Despite these troubling preliminary results, there is small reason for hope. Over the past three years, FDA experts have watched as duodenoscope-related infection rates have fallen, in part thanks to improved sanitization techniques. From a peak in 2015 of 250 reports, reports of infections related to duodenoscopes fell 62% to fewer than 100 in 2017. Unfortunately, the numbers again skyrocketed in 2018. The FDA says it received 205 medical device reports between October 15, 2018 and March 31, 2019 – with 45 reports of patient infection, 1 report of patient exposure and 159 reports of device contamination.

“These reports indicate that although the number of reports has declined, there continues to be a need for improvement of the safety of reprocessed duodenoscopes,” the FDA concludes. Apparently, a real solution has yet to appear; duodonescope infection rates remain unacceptably high, leaving thousands of patients at risk.

Three Patient Deaths Reported In 2018

Several dozen patients have died due to infections traced back to the medical devices, including 3 in 2018. Meanwhile, a federal criminal investigation of Olympus, the world’s primary duodenoscope manufacturer, remains ongoing in New Jersey. Criminal prosecutors are now attempting to determine how much the company knew about its medical device’s risks.

In light of the new preliminary results, FDA Center for Devices & Radiological Health director Dr. Jeffrey Shuren reiterated the agency’s commitment to ensuring that duodenoscopes can be properly sanitized. “We’d like to see strong evidence that proper cleaning and reprocessing can virtually eliminate any bacteria residue that can spread infections,” Shuren said. “Currently, that evidence is lacking, and we’re considering what additional regulatory actions may be necessary.”

The FDA has also chosen to consult with the Centers for Disease Control & Prevention “to obtain their input and guidance on the issue of infection control and reprocessing of these difficult-to-clean scopes,” Shuren added.