Can gastrointestinal endoscopy transmit hepatitis B to patients?

[Gastrointestinal endoscopy and infection]

During a gastrointestinal endoscopy, the device crosses natural cavities with always commensal bacterial flora, sometimes pathogenic flora. In all cases, the device is contaminated after the exam. The lack of effective disinfection exposes to the risks of transmission of germs. The infectious risk depends on the patient, the endoscopic procedure as well as on the technique of disinfection. The bacteraemia is usually not clinically significant. The endoscopic transmission of the germs from a patient to another one is very rare and is mostly due to a defect of disinfection. The procedures for disinfecting equipment should be known, established and controlled.

Health care-associated transmission of hepatitis B and C viruses in endoscopy units

The risk for potential transmission of infectious agents during gastrointestinal (GI) endoscopy is concerning for patients and physicians. However, the instance of infection transmission remains rare after GI endoscopy procedures, with an estimated frequency of 1 in 1.8 million procedures. Endoscopy-related infection may occur when microorganisms are spread or transmitted from patient to patient by contaminated endoscopic or accessory equipments; from the GI tract through the bloodstream during endoscopy to susceptible organs or prostheses, or spread to adjacent tissues that are breached as a result of the endoscopy procedure; or from patients to endoscopy personnel and perhaps from endoscopy personnel to patients. Proper cleaning, disinfection, and reprocessing of endoscopies and accessories, and appropriate administration of intravenous drugs help to minimize the risk for infection transmission.

Current issues in endoscope reprocessing and infection control during gastrointestinal endoscopy

The purpose of this article is to review the evidence regarding transmission of infection during gastrointestinal endoscopy, factors important in endoscope reprocessing and infection control, areas to focus on to improve compliance, and recent developments and advances in the field.

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.

Frequency of detectable HBsAg in fluid adherent to the endoscope, gastric juice, and saliva collected during endoscopy in patients positive for HBsAg

Gastric juice, saliva, and fluid adherent to the endoscope were collected from 50 patients who were seropositive for hepatitis B surface antigen (HBsAg) during the endoscopic examination of the upper gastrointestinal tract, and examined for HBsAg, using the radioimmunoassay. A positive test was obtained from 42.0% of the saliva samples, in 32.0% of the gastric juice specimens, and in 31.3% of the fluid adherent to the scope. These results should be taken as a warning, that calls for a more careful screening of the patients and disinfection of the endoscope.

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.

Use of buffered hypochlorite solution for disinfecting fibrescopes

The possible use of sodium hypochlorite solution buffered to pH 7.6 and containing 100 ppm available chlorine (avCl) for disinfecting fibrescopes was investigated. A flexible fibrescope experimentally contaminated with Pseudomonas putida, Mycobacterium fortuitum, or Bacillus subtilis spores was effectively disinfected within 10 m in repeatedly and without any observable adverse effect on the instrument. The corrosive nature of buffered hypochlorite was investigated by immersing various fibrescope components and metal wires in solutions of different strength for long periods and examining them for damage. Stainless steel, platinum, glass, Teflon, polythene and epoxy resin were apparently unaffected whereas polyurethane, rubber and other metals tested were damaged to different extents. Buffered hypochlorite solutions may have many applications pertaining to the disinfection of items which are either thermolabile or require rapid effective disinfection.

Infectious complications of gastrointestinal endoscopy

The relationships of infectious disease and fiberoptic gastrointestinal endoscopy have been reviewed. After a decade of burgeoning fiberoptic use, endoscopically related infections have occurred, but with remarkable rarity, despite lack of uniformity in endoscopic cleansing techniques. Transmission of viral disease has not been demonstrated. Reported bacterial cross infections have occurred under variable cleansing conditions which did not include disinfection. Transient low level bacteremia occurs following gastrointestinal endoscopy, and is generally inconsequential. Prophylactic antibiotics against gram negative organisms are to be considered in the patient with a prosthetic valve, because of theoretical risks which have not been clinically observed. Problems of cross infection and bacteremia can be generally avoided by various measures, but can most certainly be precluded by use of disinfectants, which maximally suppress microorganisms. Endogenous infection, chiefly evident as aspiration pneumonia, is likely underreported but uncommon, and prevention is probably related in part to good endoscopic technique. Infections are not an important complication of gastrointestinal endoscopy.

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.

Failure of endoscopic transmission of hepatitis B

Emergency endoscopy was performed on two patients subsequently found to be hepatitis B surface antigen carriers. Before their carrier state was determined, nine other patients underwent endoscopy using the same instruments, which had been routinely cleaned between procedures. These patients were all notified within five days of the incident, given standard gamma globulin, and prospectively followed for the development of hepatitis. After one of the endoscopes was gas sterilized, the next three patients undergoing endoscopy were also followed. One of the hepatitis B surface antigen carriers was positive for antibody to e antigen; the other carrier had neither e antigen nor antibody. None of these individuals developed signs or symptoms of hepatitis, abnormal serum glutamic pyruvate transaminase elevations, or serologic evidence of hepatitis B exposure. From these data, and other recorded experiences, it appears that routine cleansing of endoscopy equipment is sufficient in preventing the transmission of hepatitis B.