FDA Investigates Duodenoscope Disinfection Methods After Reports of InfectionsFeb 27, 2015
The Food and Drug Administration (FDA) has asked duodenoscope manufacturers to provide evidence that their recommended disinfection methods work, after the devices recently infected seven patients with drug-resistant bacteria.
Dr. Stephen Ostroff, the FDA’s chief scientist, said the recent infections at Ronald Reagan UCLA Medical Center show that additional precautions may be needed. Duodenoscopes have been implicated in infections at a number of hospitals, The New York Times reports. In 2013, 39 patients at Advocate Lutheran General Hospital in Park Ridge, Ill., were infected with carbapenem-resistant Enterobacteriaceae (CRE), which is also the cause of the Los Angeles infections. Virginia Mason Hospital in Seattle reports that 32 patients were infected with CRE by duodenoscopes from late 2012 to early 2014, and 11 patients died.
The duodenoscope, a long, flexible tube with a tiny camera at the tip, is inserted down the patient’s throat to examine and treat pancreatic and bile duct disorders. About 500,000 procedures are done in the U.S. annually.
The duodenoscope is difficult to clean and disinfect. Even when hospitals "appear to be doing everything right, there has been transmission of CRE," Dr. Arjun Srinivasan, associate director for health care associated infection prevention programs at the Centers for Disease Control and Prevention told the Times.
In the standard disinfection procedure, the worker uses tiny brushes to clean the device’s crevices and then flushes hard-to-reach inner parts with a disinfecting chemical. But a CDC team investigating the Illinois infections found that duodenoscopes remained contaminated with CRE even when there were no recognized lapses in this cleaning process, according to the Times. The FDA is investigating other measures that could be taken, such as sterilizing the device with toxic gas. After Ronald Reagan UCLA Medical Center and Advocate Lutheran General Hospital began sterilizing their instruments with ethylene oxide gas, neither hospital has had additional cases of CRE. But ethylene oxide is potentially toxic both to the patient, if the device is not thoroughly aired after disinfection, and to the people who do the cleaning.
Dr. Ostroff of the FDA said none of the disinfecting procedures are easy to implement on a widespread basis, and he thinks the devices themselves may need to be redesigned, according to the Times.