The "superbug" has been identified as carbapenem-resistant Enterobacteriaceae (CRE). According to the Centers for Disease Control and Prevention, CRE is "a family of germs" highly resistant to antibiotics.
In a previous news release, the CDC had said that same bacteria can kill up to half of all patients who become infected with it in their bloodstreams. The report added that almost all CRE infections "occur in people receiving significant medical care in hospitals, long-term acute care facilities, or nursing homes."
CDC director Dr. Tom Frieden has called CRE a "nightmare bacteria."
"Our strongest antibiotics don't work and patients are left with potentially untreatable infections," Frieden said in 2013.
An internal investigation by UCLA determined that CRE bacteria "may have been transmitted during a procedure that uses (a) specialized scope to diagnose and treat pancreaticobiliary diseases and a contributing factor in the death of two patients," reads the statement provided by UCLA's Irwin.
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Pancreaticobiliary diseases can include gallstones, acute and chronic pancreatitis, and pancreatic cancer, according to the CDC.
UCLA medical personnel "sterilized the scopes according to the standards stipulated by the manufacturer," the statement read. Also, the two scopes involved the infection each were "immediately removed," and UCLA is now using a decontamination process that exceeds manufacturer and national standards.
UCLA patients who may have been exposed to the "superbug' are being offered free home-testing kits that can be analyzed at the hospital.
In the internal email from Bobrowsky, sent Wednesday, he notes the Los Angeles County Health Department has been working with UCLA Ronald Reagan Medical Center "after they reported 7 cases of (CRE) infection among patients who had an endoscopic retrograde cholangiopancreatography procedure."
And during an onsite visit by county health officials to the hospital "no infection control breaches were observed."
County health officials are continuing to work with the facility — and CDC experts also are working with the Food and Drug Administration "regarding this and other reports of outbreaks/cases associated with" the same types of instruments, called duodenoscopes.
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One of those reports was an outbreak of CRE among at least 32 patients at Seattle's Virginia Mason Medical Center between 2012 and 2014, that was just revealed last month.
In addition, the manufacturers of the duodenoscopes under scrutiny are reportedly working with the FDA regarding these reports.
"Outbreaks associated with duodenoscopes have been reported in the literature in the past," Bobrowsky wrote. "Investigation of a past outbreak conducted by the CDC has reported that the design of the duodenoscope may be an issue because it makes cleaning difficult."
"They stated in this previous report that the devices have the potential to remain contaminated even after recommended reprocessing is performed," he added.
The FSA said it was "aware of and closely monitoring the association between reprocessed endoscopes and multidrug-resistant bacterial infections" caused by CRE.