The Food and Drug Administration warned doctors that bronchoscopes may transmit infections among patients when inadequately cleaned, the latest alert by the regulator about the risk of reusable medical scopes.
The agency recorded 109 reports of infections or contamination related to bronchoscopes in the past five years, including 50 in 2014 alone, according to its safety notice. "A small number" of the incidents showed that the devices remained contaminated even when manufacturers’ cleaning instructions were followed, the agency said.
Similar problems prompted the FDA to warn about devices known as duodenoscopes earlier this year, after hospitals in Seattle, Los Angeles, and elsewhere linked them to outbreaks of drug-resistant bacteria that caused at least 13 deaths. The FDA has cited the intricate design of duodonescopes, which are used to reach tiny ducts in the small intestine, as a particular risk.
Now it seems that less complex instruments are also drawing more scrutiny. Infection control consultant Lawrence Muscarella raised concerns about the risk of bronchoscopes in a July blog post.
Medical scopes are difficult to clean because they have hidden internal channels that can harbor bacteria. "You’re doing a blind process," said Chris Lavanchy, engineering director at the patient safety group ECRI Institute, in an interview last month. "You’re flushing them, you’re running brushes through them, with the expectation that you’ll release any debris in them." The group has warned about the risks of reusable scopes for years.
Bronchoscopes are threaded through the nose or mouth to examine patients’ airways. The FDA says they’re used in about half a million procedures a year, so the number of recorded cases of contamination is relatively small. The benefits of bronchoscopy outweigh the risk of infection for most patients, the FDA says, but patients should talk to their doctors about the decision. The agency has acknowledged that its system for tracking adverse events suffers from underreporting, and it recently warned manufacturers about lapses in documenting adverse events.
A Bloomberg review of federal and state records found at least 32 cases of contaminated bronchoscopes or cystoscopes, which are threaded through the urethra, that together have affected at least 166 patients since 2013. The true number could be higher, because many states don’t collect records on such events, and hospitals don't have to disclose them publicly. The names and locations of hospitals involved are generally left out.
In Kentucky, at least 15 people were exposed to a bug called B. cepacia linked to bronchoscopes whose cleaning equipment had a faulty water filter, according to a conference presentation by epidemiologists this year. In an unidentified state, 22 people tested positive for E. coli and P. aeruginosa last year after being treated by different doctors who used the same bronchoscope, according to FDA records. The report said all the patients recovered.
The FDA's latest warning shows the agency is working to alert health-care providers and patients to the risks of contamination in devices that involve complex cleaning instructions. The agency warned doctors to strictly follow manufacturers' cleaning instructions and take any scope with visible damage out of service. The notice also stresses the need for proper maintenance, storage, and quality control to prevent infections.
After the duodenoscope outbreaks came to light last winter, the regulators finalized cleaning guidelines that had been under review for nearly four years. That document identified a set of instruments, including bronchoscopes, that "represent a high risk of infection” if they’re not cleaned properly.
The guidelines make no mention of cystoscopes, which have been linked to transmissions in the FDA’s own records and those of state health departments. In New York state in 2013, four patients who had cystoscopies at an outpatient clinic tested positive for the same strain of the superbug CRE, according to state health department records obtained by Bloomberg. Whether the procedure was the source of the infections was “inconclusive,” the department said.
The FDA monitors data on reprocessed devices and will inform the public “if we find that there is a public health concern associated with a specific device type or model,” FDA spokeswoman Jennifer Dooren said in an email. The regulator is “proactively investigating” devices it’s identified as higher risk for infection if cleaning lapses occur, she said.
A study by Mayo Clinic researchers published in August found that other types of scopes—colonoscopes and gastroscopes—routinely remained contaminated with microbes and debris after cleaning and disinfection. "Results from this study suggest current standards and practices may not be sufficient for detecting and removing all residual contamination,” the Mayo Clinic authors wrote.
That research, published in the American Journal of Infection Control, didn't establish the actual risk of transmitting bacteria to patients. People shouldn’t avoid needed medical procedures, said the Mayo Clinic’s Pritish Tosh, one of the study’s authors, in an interview last month. More research is needed to determine the risk of contaminated scopes spreading pathogens from patient to patient.
But evidence of contamination on devices that are less complex than duodenoscopes should get hospitals’ attention. "Even on the more simple scopes, we are finding that there are residual bacteria,” Tosh said.
Updates with comments from the FDA.