Duodenoscopes versus Endoscopes, Understanding the Difference

Two weeks ago, two patients at UCLA died from a serious infection felt to be introduced during a procedure called an ERCP (Endoscopic Retrograde Cholangiopancreatogram). The infection was due to an antibiotic resistant “superbug” referred to as CRE, or carbapenem resistant enterobacteriaceae, passed on to the patient through use of the duodenoscope used during an ERCP.  In light of the press accounts of these events, I wanted to explain how this procedure differs from routine endoscopic procedures (those performed by gastroenterologists) and to clarify how these infections can occur, although they are very rare.  I also wanted to reassure the public that the UCLA cases were not associated with colonoscopy.

A duodenoscope is an instrument that is used for only this specific procedure, ERCP.  ERCP is done when there is concern about your bile duct or pancreatic duct that cannot be diagnosed or treated otherwise. Under anesthesia this tube, the duodenoscope is thread through your mouth, esophagus and stomach into the duodenum in order to reach the entrance of the bile duct and pancreatic ducts.  Examples of some conditions that may warrant ERCP are gallstones in the bile duct, infection related to blockage of this bile duct, and pancreatitis (inflammation of the pancreas). A duodenoscope IS NOT used for a routine endoscopy which many of our readers may have had for symptoms like heartburn, trouble swallowing or abdominal pain. The difference between the duodenoscope and an endoscope is that the former has a lever with a hinge that enables the doctor to angle a cannula or small tube into the pancreatic duct or bile duct to be able to see them. This hinge is very difficult to clean on a microscopic level and is felt to be the culprit in harboring these drug resistant bacteria, even with adherence to cleaning and reprocessing guidelines issued by the manufacturer.

An endoscope is a tube which also is used to access the esophagus, stomach and duodenum during endoscopy or EGD, but it does not have this hinge or lever and is therefore much more effectively cleaned.  To put it in perspective, in my 23 years of practice, I never once had a patient develop a related infection after endoscopy.

The FDA has issued a warning based on receiving 75 medical device related reports of infections associated with the duodenoscope, between January 2013 and December 2014. http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm434871.htm. UCLA, where the infections occurred, had followed national guidelines to clean their duodenoscopes and is now taking extra precautions in their decontamination process.

So what are the take home points for the patient?  First recognize that endoscopy and ERCP are different procedures that use different instruments and the risk of infection with endoscopy is extremely low when the manufacturer’s cleaning/processing guidelines are followed. Second, as with all procedures, discuss the risks and benefits of the recommended ERCP with your physician. Typically, ERCP is performed for serious conditions, some that may be life threatening, and so the benefits far outweigh the risks. However, always ask your physician if there are safer alternatives to consider.  Finally, recognize that bacterial resistance is on the rise and there is much that the patient can do to help prevent this. Don’t take antibiotics for a viral infection such as the flu.  When prescribed antibiotics, be sure to complete the course recommended by your physician.  Do not let these recent reports prevent you from having colonoscopy, an important cancer screening procedure (which Julia just wrote about in another Lady Docs blog).