Contaminated medical devices blamed for a series of hospital superbug outbreak are now linked to an outbreak of a drug-resistant Escherichia coli (E. coli) in a Washington state hospital.
A study published in Infection Control & Hospital Epidemiology reports that the specialized endoscopes may infect more patients despite a hospital’s use of the manufacturer’s recommended cleaning procedures for the reusable devices. Eleven patients died, although not all the deaths could be tied to the E. coli infections because the patients suffered from cancer or other serious illnesses. At Seattle’s Virginia Mason Medical Center, 32 patients were infected with an antibiotic-resistant strain of E. coli between November 2012 and August 2013, even though the hospital followed the company’s procedure for cleaning the scopes, according to FierceHealthcare.
Recent evidence suggests the manufacturer’s cleaning instructions may not be sufficient to fully sterilize the devices. Similar concerns arose about contaminated duodenoscopes associated with an outbreak of carbapenem-resistant Enterobacteriaceae (CRE). More than 3 in 10 infected patients died over the course of the investigation, with seven deaths occurring during hospitalization within 30 days of the hospital identifying the superbug as E. coli, FierceHealthcare reports. Dr. Kristen Wendorf of King County, Seattle public health department, said, “In the wake of the recent outbreak of CRE due to contaminated endoscopes, we suspect endoscope-associated transmission of bacteria is more common than recognized and not adequately prevented by current reprocessing guidelines.”
A review of the Olympus scopes used at Virginia Mason found seven of eight contained mechanical defects that may have contributed to the bacteria’s spread. The hospital has begun manual cleaning of the scopes, and is taking measures beyond the manufacturer’s recommendations. After cleaning, the hospital quarantines the devices for 48 hours, the Los Angeles Times reports. Even after this process, the hospital found 3 percent of scopes were still contaminated, and staff repeated the process. Virginia Mason spokesman Gale Robinette said, “No scope is used at Virginia Mason until the cultures are negative.”
Duodenoscopes—flexible, lighted tubes with a miniature camera—are threaded through the mouth, throat, stomach, and into the top of the small intestine (the duodenum), the FDA explains. The devices are used to obtain tissue samples for biopsy or to treat certain abnormalities. About 500,000 such procedures are performed annually in the United States and regulators stressed that the device is essential for treating tumors, gallstones and other blockages around the pancreas and bile ducts. Olympus, Pentax Medical and Fujifilm manufacture the devices in the U.S.
In February, the Food and Drug Administration (FDA) issued a warning about duodenoscopes following CRE outbreaks in California. The new FDA guidelines recommend that hospitals take scopes out of service until they are verified to be pathogen-free, FierceHealthcare reported. In March, the FDA revised guidelines for manufacturers of the scopes, requiring that they prove they can be adequately cleaned before the scopes enter the market.
Health officials called it “especially disturbing” that the Seattle hospital had meticulously followed the company’s instructions for cleaning the scopes but still had 32 infected patients.