Ronald Reagan Medical Center at UCLA in Los Angeles in 2010. (AP Photo/Nick Ut)

The Food and Drug Administration on Thursday warned doctors and hospitals around the country that a commonly used medical scope could be difficult to clean and  “may facilitate the spread of deadly bacteria.”

The agency’s warning comes after seven patients were infected and two died from a drug-resistant “superbug” at UCLA’s Ronald Reagan Medical Center. Public health authorities are tracking down at least 179 other patients who might have been exposed to the dangerous bacteria through the use of contaminated medical scopes.

The affected patients suffered from a drug-resistant superbug known as CRE, or Carbapenem-Resistant Enterobacteriaceae, during “complex endoscopic procedures” to diagnose and treat diseases in the pancreas between October and January at the hospital, UCLA’s Health System said late Wednesday in an emailed statement.

In its warning on Thursday, the FDA noted that the medical scopes in question, known as duodenoscopes, are used in more than half a million procedures each year in the United States as the “least invasive way” of draining fluids from pancreatic and biliary ducts blocked by tumors, gallstones and other conditions. The light, flexible tubes are typically threaded through the mouth, throat, stomach, or into the top of the small intestine. Unlike other endoscopes, they have a movable “elevator” mechanism at one end that allows the instrument to treat problems with fluid drainage.

But that intricate design also can make the devices difficult to sterilize, the FDA said. Cleaning the scopes is “a detailed, multi-step process,” and meticulously following the manufacturer’s directions for disinfecting them “should reduce the risk of transmitting infection, but may not entirely eliminate it,” the agency said. The FDA also noted that recent medical publications and adverse event reports it had received had associated drug-resistant bacterial infections with patients who had undergone procedures using the scopes.

UCLA told the Los Angeles Times, which first reported the deadly infections, that it detected the bacteria last month while conducting tests on a patient and alerted both the California and Los Angeles County health departments. An internal investigation revealed that two medical endoscopes may have transmitted the infection, though the scopes had been sterilized in line with the manufacturer’s standards, it said.

Two people have died, at least seven others are possibly infected and more than 100 might have been exposed to a drug-resistant "superbug" at UCLA's Ronald Reagan Medical Center in Los Angeles. (Reuters)

Health officials sent out letters this week to 179 patients who were possibly exposed to the bacteria through one of the endoscopes, Los Angeles County Department of Public Health said in a statement.

“We notified all patients who had this type of procedure, and we were using seven different scopes. Only two of them were found to be infected. In an abundance of caution, we notified everybody,” UCLA spokesman Dale Tate told the Associated Press.

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The CRE superbug has been described as a form of “nightmare bacteria” by Tom Frieden, head of the Centers for Disease Control and Prevention. “Our strongest antibiotics don’t work and patients are left with potentially untreatable infections,” he said. CRE infections, most of which happen in hospital settings, can lead to infections in the bladder or lungs, causing coughing, fever or chills. And, according to the CDC, the bacteria kills nearly half of patients who get infections in the bloodstream.

The patients infected at the Ronald Reagan Medical Center had undergone a procedure called an ERCP, or endoscopic retrograde cholangiopancreatography, the Los Angeles Times reported. The test uses an endoscope along with X-ray images to examine the pancreatic system to help diagnose tumors or treat gallstones, for instance. It is not the same one used for more common endoscopies and colonoscopies, the newspaper said.

Over the past couple years, similar outbreaks have occurred when contaminated scopes were used at Advocate Lutheran General Hospital near Chicago, where 44 people were infected, and at the Virginia Mason Medical Center in Seattle, where at least 32 patients became ill and 11 died. Although it was unclear whether the outbreak in Seattle contributed to the deaths, the hospital stressed that medical professionals there, too, had cleaned the instruments according to the manufacturer’s stipulations.

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“There is either a design issue to be addressed or a change to the guidelines for the cleaning process,” Andrew Ross, section chief of gastroenterology at Virginia Mason, told the Los Angeles Times. “It’s the role of the federal government to make some of those decisions.”

Olympus Medical Systems Group, which is UCLA’s endoscope supplier, told the Los Angeles Times it is working with the FDA as well as doctors and hospitals to address public health concerns.

Patients who may have been exposed at Ronald Reagan Medical Center have been given a home-testing kit that medical professionals will analyze. The university is now taking steps to ensure patients’ safety.

“The two scopes involved with the infection were immediately removed and UCLA is now utilizing a decontamination process that goes above and beyond the manufacturer and national standards,” UCLA said in the statement.

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