Why is it so difficult to sterilize duodenoscopes, which are touched by half a million patients each year?

A duodenoscope is a long, highly malleable hose with a fiber-optic camera at one end. The entire hose can be inserted straight from the patient's mouth into the stomach and then into the upper part of the small intestine, also known as the duodenum.

This procedure, known medically as endoscopic retrograde cholangiopancreatography (ERCP), is used to diagnose and treat diseases of the pancreas, bile ducts, and gallbladder, such as potentially fatal jaundice, tumors, bile duct obstructions, and stones. In the United States, more than 500,000 people are diagnosed with ERCP each year.

In the case of duodenoscopes, it is currently very difficult to clean the inside of the narrow hose by hand, and unlike other endoscopes, duodenoscopes are also designed with a removable elevating structure at the top of the duodenoscope, with the help of which it is also possible to better adjust the exact position of the surgical instruments. However, because of this structure, the tiny cracks in the device become breeding grounds for bodily fluids and bacteria, complicating the cleaning process.

Four years ago, when the problem was just beginning to emerge, an FDA advisory panel recommended advancing the sterilization of duodenoscopes. Today, cleaning and disinfecting is primarily steam heat sterilization, but that method can break the colonoscope and cause cracks, which can lead to the proliferation of bacteria and, eventually, to having to replace the device.

In fact, modern medicine relies heavily on duodenoscopes and other flexible tube endoscopes with a camera on one end to diagnose and treat diseases without surgery. For example, bronchial endoscopes are used to examine the lungs, and colonoscopes are used to examine the large intestine for rectal cancer.

By contrast, the alternatives to these endoscopes are very limited, and often require testing for disease and procedures such as stool tests and samples to analyze for colorectal cancer if a colonoscope is not available (because the environment in which colonoscopes are used is actually teeming with all sorts of bacteria, the risk of infection with colonoscopes is much lower). lower).