DEADLY BACTERIA ON MEDICAL
SCOPES TRIGGER INFECTIONS
Superbug defies treatment, kills many victims
Peter Eisler
USA TODAY
The deadly pattern of illnesses began to emerge in 2012 at hospitals in Seattle, Pittsburgh, Chicago. In
each case, the culprit was a bacteria known as CRE, perhaps the most feared of super-bugs, because it
resists even “last defense” antibiotics — and kills up to 40% of the people it infects.
In each case, investigators identified the same source of transmission: a specialized endoscope,
threaded down the throat of a half-million patients a year to treat gallstones, cancers and other disorders
of the digestive system. They found that the devices, often called duodenoscopes, accumulate bacteria
that are not always removed by conventional cleaning, so infections can pass from patient to patient.
Neither the scopes’ manufacturers nor the Food and Drug Administration, which regulates them, have
publicized or offered guidance on the problem. Many doctors who use the scopes — and most of the
patients they treat — don’t know the risks. Nor do they know that steps can be taken to cut those risks
sharply.
“Most hospitals that do these procedures are not even looking for this problem, or they may not be
aware, and that’s got to change,” says Jeffrey Duchin, a physician who heads communicable disease
control at the Seattle and King County (Wash.) Public Health Department.
Many of the resulting infections may go unnoticed, says Du-chin, who directed the investigation of the
CRE outbreak in Seattle. In that case, seven patients died with infections associated with contaminated
duodenoscopes, five of them with CRE. (None of the deaths was attributed solely to the infections
because all of the patients also had other health problems.)
When contaminated scopes transmit CRE, it’s likely to get attention, because the infections involve
especially perilous, “red-flag” bacteria, Duchin says. More common bugs may elicit little more than a quick
prescription for antibiotics — and no investigation.
“There’s a likelihood that we’re just seeing a very small subset of the universe of infections from these
types of scopes,” Duchin says.
FDA SEES RISKS
The FDA says in a written statement to USA TODAY that it is “aware of and closely monitoring” infection
risks associated with the scopes. “Some parts of the scopes may be extremely difficult to access and
clean thoroughly,” the agency says, “and effective cleaning of all areas of the duodenoscope may not be
possible.”
The agency is studying the problem and working with manufacturers to determine whether new cleaning
protocols should be mandated or the scopes should be redesigned entirely. The scopes’ “lifesaving” ability
to detect and treat potentially fatal digestive disorders outweighs their infection risks, the statement says:
“It (is) important for these devices to remain available.”
Few dispute the scopes’ importance. But public health officials and endoscopy experts who have studied
the problem say the FDA and scope manufacturers have been slow to bring attention to the infection risks
and publicize steps hospitals can take to reduce them dramatically.
“It’s fair to ask whether the FDA could have been doing more to regulate these devices and significantly
reduce the risk of patient harm,” says Lawrence Muscarella, a biomedical engineer and independent
consultant who advises hospitals on endoscope safety. “Patients have died, and the agency seems to be
moving slowly.”
MULTIPLE OUTBREAKS
Muscarella has identified at least a half-dozen U.S. outbreaks of CRE and related superbugs since 2012
that were linked to contaminated duodenoscopes — findings he published in a peer-reviewed medical
journal in October. The biggest cases involved dozens of patients and multiple deaths, but as in the
Seattle outbreak , not all of the fatalities were attributed conclusively to CRE because some patients had
multiple ailments.
Most of the patients had undergone a procedure known as ERCP, or endoscopic retrograde
cholangiopancreatography. In the procedure, the duodenoscope is used to inject a contrast dye into the
bile and pancreatic ducts, of which X-rays are taken to reveal blockages, tumors, gallstones and other
problems.
The scope also can gather material for biopsies, remove stones or other obstructions, or install stents to
open the ducts.
Last year, after linking the CRE outbreak in Chicago to ERCP scopes, the Centers for Disease Control
and Prevention issued a warning about the risks of spreading infections among patients who undergo the
procedure.
The problem, investigators found, is that biological material can collect in the “elevator” mechanisms that
control tiny devices that extend from the tip of the duodenoscope.
Even when the devices are cleaned strictly in accordance with manufacturers’ FDA-approved guidelines,
“they have a lot of intricate mechanisms and pieces that are very difficult to disinfect,” says Alex Kallen, an
infectious-disease physician at the CDC who helped direct the investigation. “There definitely is a risk of
(disease) transmission with these scopes.”
NOT WAITING ON FDA
Several hospitals that have linked CRE cases to duodenoscopes have moved ahead without the FDA to
adopt new safety measures.
At Virginia Mason Medical Center in Seattle, officials adopted new scope-cleaning protocols and require
that all scopes be quarantined after cleaning, then tested for any residual bacteria before they can be
reused.
The hospital had to purchase more scopes and add staff to clean and test them, according to Duchin. He
says the changes cost the hospital an estimated $1 million, but no infections have been linked to the
scopes since the procedures were put in place.
At the University of Pittsburgh Medical Center and Advocate Lutheran General Hospital outside Chicago,
officials have begun using a process called EtO gas sterilization to destroy any bacteria lingering on
scopes after cleaning. The process requires special facilities and equipment because the gas is toxic, but
the hospitals have reported seeing no infections since they began using it.
Both the gas sterilization and the quarantine-and-test approaches would be difficult for hospitals that
have smaller staffs and budgets, says Marcia Patrick, a member of the education faculty with the
Association for Professionals in Infection Control and Epidemiology. But she says most hospitals should
at least consider taking occasional bacterial cultures from scopes to assess whether their disinfection
processes are working.
“The cost of culturing is not that high,” Patrick says.
REGULATORY ISSUES
The FDA says it is working with all three major manufacturers of duodenoscopes — Olympus, FUJIFILM
and Pentax — to assess potential design changes and determine whether new disinfection processes can
ensure the scopes’ safety in their current configuration. Issuing new guidance to minimize infections “is on
the agency’s priority list” for 2015, the FDA says.
In separate statements to USA TODAY, all three manufacturers said they are aware of the concerns
about infection transmission from their duodenoscopes and are working with FDA to address the issue. All
three noted that proper cleaning of the devices according to existing, FDAapproved guidance would help
minimize infection risks.
The extent of that risk remains an open question, because infections can be difficult to detect.
CRE cases get noticed because they’re so deadly and hard to treat. The bacteria are formally titled
Carbapenem-Resistant Enterobacteriaceae for their resistance to carbapenem antibiotics
— the last line of defense in the medical toolbox. They generate particular concern because CRE’s
resistance gene can transfer to other bacteria, transforming more routine bacterial infections into drugresistant scourges.
Muscarella, Patrick and others say duodenoscopes certainly transmit less serious infections that go
unnoticed. CRE cases are “probably the tip of an iceberg,” Patrick says. “We don’t know how big that
iceberg is.”
The FDA says it is considering whether to advise hospitals to do periodic bacterial testing of
duodenoscopes. Besides gauging the efficacy of disinfection practices, that could provide more data on
infection risks.
Efforts to raise awareness have been limited mainly to a few medical journal articles, the CDC alert and
advisories from physicians’ groups.
“This is a very important issue,” says Bret Petersen, a physician and board member at the American
Society for Gastrointestinal Endoscopy, which has alerted members to the infection problem. “We do
expect the FDA and the manufacturers to provide additional public guidance” on how hospitals should
address it.
LFM
Lawrence Muscarella is a biomedical engineer and independent hospital safety consultant and president
of LFM Healthcare Solutions.
CDC
Alex Kallen is an infectious-disease physician in the Division of Healthcare Quality Promotion at the
Centers for Disease Control and Prevention.