Failure of endoscopic transmission of hepatitis B

Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy. Clin Microbiol Rev. 2013;26:231-254. [PMID: 23554415 DOI: 10.1128/cmr.00085-12]

Flexible endoscopy is a widely used diagnostic and therapeutic procedure. Contaminated endoscopes are the medical devices frequently associated with outbreaks of health care-associated infections. Accurate reprocessing of flexible endoscopes involves cleaning and high-level disinfection followed by rinsing and drying before storage. Most contemporary flexible endoscopes cannot be heat sterilized and are designed with multiple channels, which are difficult to clean and disinfect. The ability of bacteria to form biofilms on the inner channel surfaces can contribute to failure of the decontamination process. Implementation of microbiological surveillance of endoscope reprocessing is appropriate to detect early colonization and biofilm formation in the endoscope and to prevent contamination and infection in patients after endoscopic procedures. This review presents an overview of the infections and cross-contaminations related to flexible gastrointestinal endoscopy and bronchoscopy and illustrates the impact of biofilm on endoscope reprocessing and postendoscopic infection.

Gastrointestinal endoscopy decontamination failure and the risk of transmission of blood-borne viruses: a review

The risk of blood-borne virus transmission with an inadequately decontaminated endoscope during gastrointestinal endoscopy remains unclear, although it is likely to be low. A systematic review of the literature was undertaken to determine previous episodes of blood-borne virus transmission in these circumstances. In total, 31 articles were included in this review. No articles relating to possible transmission of human immunodeficiency virus were identified. The articles included were generally case series or case reports and were written prior to the comprehensive endoscope decontamination guidelines in use today. The results suggest that hepatitis B and hepatitis C transmission are low during endoscopy with an inadequately decontaminated endoscope.

Disinfection of endoscopic equipment

Patients undergoing endoscopy are at risk of infection from the use of contaminated equipment. Dangers arise from the transmission of organisms from one patient to another and from the introduction of opportunist organisms which colonize endoscopic equipment on storage and can lead to sepsis and death in those who are immunocompromised and at ERCP. Staff are in danger from needle-stick injury and sensitivity to aldehyde disinfectants. These risks can be eliminated by careful attention to disinfection techniques. The most important part of endoscope disinfection is thorough mechanical cleaning first, followed by 5-10 min total immersion of the instrument and all channels in 2% glutaraldehyde (or the equivalent). At the end of the endoscopy list, following the disinfection protocol, all equipment should be dried internally and externally prior to storage. Staff must be fully aware of the risks of infection in endoscopy, be protected from hepatitis B by vaccination, and be fully trained in disinfection techniques. Glutaraldehyde should be used only in closed systems or in well-ventilated areas with the operator protected from direct contact from splashing and fumes. Institutions should designate an individual to be responsible for preparing, monitoring and overseeing disinfection procedures within the endoscopy room and for ensuring that regular microbiological testing of equipment (including automatic disinfecting machines) is undertaken.

Contamination of an endoscope due to Trichosporon beigelli

Trichosporon beigelli was isolated from the gastric aspirates of ten patients who had undergone endoscopy. Suspecting fungal contamination of the endoscopic equipment, samples from the biopsy channel, the water bottle, aspiration catheter and the tip of the endoscope were examined. Only the sample from the biopsy channel showed fungal elements on direct examination and grew Trichosporon beigelli. The original source for the fungus was an immunocompromised patient who had undergone endoscopy earlier. This episode occurred despite adherence to apparently adequate disinfection procedures for endoscopes. Because of the risk of cross-infection, especially in immunocompromised patients, it is imperative to take special steps to prevent fungal contamination of endoscopes.

Complications and hazards of gastrointestinal endoscopy

The diagnostic and therapeutic contribution of fiberoptic endoscopy to the advancement of the knowledge of gastrointestinal disease and to its proper management is already established. Technical refinements in the new instruments and extensive acceptance of the advantages of the method makes fiberendoscopy a procedure widely used throughout the world. Therefore, the appreciation of its potential risk of complications and hazards is justified. This review summarizes the complications and hazards of fiberoptic gastrointestinal endoscopy gleaned from reports of endoscopic surveys and individual experiences. Causes and means whereby complications related to upper intestinal and colonic endoscopy can be prevented or treated are discussed.

Gastrointestinal endoscopy and HBV infection: no evidence for a causal relationship. A prospective controlled study

The importance of the different endoscopic procedures in the transmission of hepatitis B was investigated prospectively by following up for 6 months all HBV-negative patients endoscoped from April to October 1981. A group of patients admitted in the same period to our unit constituted the control group. Controls were obtained after 1, 3, and 6 months from endoscopy. Infection rate was 1% for the control group and 0.45% for the endoscopy group. The difference is not statistically significant. These results strongly support the view, already present on an uncontrolled basis in the literature, that transmission of hepatitis B is not associated with gastrointestinal endoscopy.

Gastrointestinal endoscopy: infection and disinfection

The past decade has seen the development of an array of complex flexible fibreoptic instruments for gastrointestinal (GI) endoscopy, and an increasing use of these for diagnostic and therapeutic purposes. It has been recognised more recently that the use of contaminated endoscopic equipment can lead to serious and occasionally fatal infections. Infection with a wide variety of micro-organisms has been reported following oesophago-gastroduodenoscopy (OGD) and endoscopic retrograde cholangio-pancreatography (ERCP).

Endoscopic transmission of hepatitis B virus

Although transmission of hepatitis B virus (HBV) infection has long been recognised as a potential hazard of gastrointestinal endoscopy, there has been little evidence of direct patient-to-patient cross-infection after such procedures. We wish to report a case of type B viral hepatitis almost certainly acquired at endoscopy from an instrument sterilised in the conventional manner, but which had been used on the previous day on a patient with bleeding oesophageal varices who was incubating type B viral hepatitis.

Complications of fiberoptic endoscopy

This review summarizes the complications of fiberoptic peroral endoscopy, endoscopic retrograde cholangiopancreatography and colonoscopy gleaned from reports of extensive endoscopic surveys. Unique individual experiences are also included. Means whereby complications can be prevented or remedied are noted.