LOS ANGELES (AP) - Contaminated medical instruments are suspected in a "superbug" outbreak at a Los Angeles hospital that has infected at least seven patients, two of whom died. More than 170 others may have been exposed to the antibiotic-resistant bacteria.
They were potentially infected with Carbapenem-Resistant Enterobacteriaceae, or CRE, during endoscopic procedures at Ronald Reagan UCLA Medical Center between October and January, UCLA spokeswoman Dale Tate said. Tests on a patient uncovered the outbreak.
Similar outbreaks of potentially lethal CRE have been reported around the nation. They are difficult to treat because some varieties are resistant to most known antibiotics. By one estimate, CRE can contribute to death in up to half of seriously infected patients, according to the U.S. Centers for Disease Control and Prevention.
The bacteria may have been a "contributing factor" in the deaths of two patients, UCLA said in a statement. Those who may have been exposed are being sent free home-testing kits that the university will analyze.
The bacteria can cause infections of the bladder or lungs. Symptoms can include coughing, fever and chills.
UCLA said Wednesday that the infections may have been transmitted through two endoscopes used to diagnose and treat pancreatic and bile-duct problems.
An endoscope is an instrument that is inserted into the body to enable a doctor to view an organ or cavity. It typically consists of a thin, flexible tube with a light and a lens or miniature camera.
"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," Tate said.
The two medical devices carried the bacteria even though they had been sterilized according to the manufacturer's specifications, UCLA said.
"We removed the infected instruments, and we have heightened the sterilization process," Tate said.
On Thursday, the U.S. Food and Drug Administration issued an advisory warning doctors that even when a manufacturer's cleaning instructions are followed, infectious germs may linger in the devices. Their complex design and tiny parts make complete disinfection extremely difficult, the advisory said.
National figures on the bacteria are not kept, but 47 states have seen cases, the CDC said.
Since 2012, there have been about a half-dozen outbreaks reaching as many as 150 patients, according to the Los Angeles Times, which first reported the UCLA outbreak.
One occurred in Illinois in 2013. Dozens of patients were exposed to CRE, with some cases apparently linked to a tainted endoscope used at a hospital.
A Seattle hospital, Virginia Mason Medical Center, reported in January that CRE linked to an endoscope sickened at least 35 patients, and 11 died, though it was unclear whether the infection played a role in those deaths.
Experts say the cases represent a disturbing surge.
"This bacteria is emerging in the U.S., and it's associated with a high mortality rate," CDC epidemiologist Dr. Alex Kallen told the Times. "We don't want this circulating anywhere in the community."