Infectious complications of endoscopic retrograde cholangiopancreatography. A prospective assessment

How to implement adverse events as a quality indicator in gastrointestinal endoscopy

Quality improvement through the registration of endoscopy-related adverse events (AEs) has been recognized by major international endoscopy societies as an important quality indicator. The theory behind this is easier to approve than its implementation in daily practice. The results of many valuable attempts have been published in the literature, mainly highlighting the diverse hurdles trying to capture events related to endoscopy and the sedation used for endoscopic procedures. The current review discusses the difficulties encountered attempting to register AEs and incidents related to endoscopic procedures. Government-driven and financed health-care databases with automated coupling of specific data seem the only efficient way to implement endoscopy-related AEs and outcomes on a prospective and complete basis. This will not only allow continuous confidential feedback to endoscopists in relation to the pooled national benchmark data, but also follow-up in time through data-driven credentialing aiming to progressively optimize these benchmark data.

Implementation of remote video auditing with feedback and compliance for manual-cleaning protocols of endoscopic retrograde cholangiopancreatography endoscopes

A pilot initiative to assess the use of remote video auditing in monitoring compliance with manual-cleaning protocols for endoscopic retrograde cholangiopancreatography (ERCP) endoscopes was performed. Compliance with manual-cleaning steps following the initiation of feedback was measured. A video feed of the ERCP reprocessing room was provided to remote auditors who scored items of an ERCP endoscope manual-cleaning checklist. Compliance feedback was provided in the form of reports and reeducation. Outcomes were reported as checklist compliance. The use of remote video auditing to document manual processing is a feasible approach and feedback and reeducation increased manual-cleaning compliance from 53.1% (95% confidence interval, 34.7-71.6) to 98.9% (95.0% confidence interval, 98.1-99.6).

Infectious complications in gastrointestinal endoscopy and their prevention

Gastrointestinal endoscopes are medical devices that have been associated with outbreaks of health care-associated infections. Because of the severity and limited treatment options of infections caused by multidrug-resistant Enterobacteriaceae and Pseudomonas aeruginosa, considerable attention has been paid to detection and prevention of these post-endoscopic outbreaks. Endoscope reprocessing involves cleaning, high-level disinfection/sterilization followed by rinsing and drying before storage. Failure of the decontamination process implies the risk of settlement of biofilm producing species in endoscope channels. This review covers the infectious complications in gastrointestinal endoscopy and their prevention and highlights the problem of infection risk associated with different steps of endoscope reprocessing.

A quarantine process for the resolution of duodenoscope-associated transmission of multidrug-resistant Escherichia coli

BACKGROUND

Because of their complex design, duodenoscopes have been long recognized to be difficult to fully disinfect and may play a role in transmission of bacteria between patients. Recent reports of duodenoscope-associated carbapenem-resistant enterobacteriaceae transmission have confirmed these suspicions. An outbreak of a multidrug resistant strain of Escherichia coli was recently reported at our institution. Herein we report the results of our investigation and the process improvements that we deployed in an effort to contain the outbreak.

METHODS

A full investigation into the environment, endoscopists, infection control practices, high-level disinfection process as well as endoscopes was undertaken in conjunction with the local county health authority and the Centers for Disease Control and Prevention. Duodenoscopes were cultured and quarantined for 48 hours until negative cultures were obtained. Ergonomic changes were made to the endoscope reprocessing area, duodenoscopes were returned for routine maintenance, and surveillance cultures were obtained from all patients undergoing ERCP.

RESULTS

Between November 2012 and August 2013, 32 patients were found to harbor 1 of 2 clonal strains of multidrug-resistant E coli, all of whom had undergone ERCP or duodenoscopy. A total of 1149 ERCPs were performed during this time period. Seven patients died within 31 days of the organism being identified in culture, 16 patients died overall by March 2015. The exact contribution of E coli to death is unclear because most patients had underlying late-stage malignancy or other severe medical comorbidities. No breach in high-level disinfection protocol or infection control practices was identified. The clonal strain of E coli was identified in culture on 4 of 8 duodenoscopes, 3 of which required critical repairs despite lack of obvious malfunction. The defect rate in high-level disinfection of duodenoscopes was 2% over a 1-year period. The implemented quality improvements, subsequent to which 1625 ERCPs have been performed, were successful in halting the outbreak.

CONCLUSIONS

The existing manufacturer-recommended high-level disinfection protocols for duodenoscopes are inadequate. Although the ultimate solution may be a design change to the instrument, the timeline for such a change appears long and potentially difficult to exact. In the interim, a reliable method to ensure that bacterial pathogens are not present on the duodenoscope after high-level disinfection is needed.

Novel lipophilic probe for detecting near-membrane reactive oxygen species responses and its application for studies of pancreatic acinar cells: effects of pyocyanin and L-ornithine

AIMS

The aim of this study was to develop a fluorescent reactive oxygen species (ROS) probe, which is preferentially localized in cellular membranes and displays a strong change in fluorescence upon oxidation. We also aimed to test the performance of this probe for detecting pathophysiologically relevant ROS responses in isolated cells.

RESULTS

We introduced a novel lipophilic ROS probe dihydrorhodamine B octadecyl ester (H2RB-C18). We then applied the new probe to characterize the ROS changes triggered by inducers of acute pancreatitis in pancreatic acinar cells. We resolved ROS changes produced by L-ornithine, L-arginine, cholecystokinin-8, acetylcholine, taurolithocholic acid 3-sulfate, palmitoleic acid ethyl ester, and the bacterial toxin pyocyanin. Particularly prominent ROS responses were induced by pyocyanin and L-ornithine. These ROS responses were accompanied by changes in cytosolic Ca(2+)concentration ([Ca(2+)]i), mitochondrial membrane potential (ΔΨ), and NAD(P)H concentration.

INNOVATION

The study describes a novel sensitive lipophilic ROS probe. The probe is particularly suitable for detecting ROS in near-membrane regions and therefore for reporting the ROS environment of plasma membrane channels and pumps.

CONCLUSIONS

In our experimental conditions, the novel probe was more sensitive than 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein (CM-H2DCF) and dihydrorhodamine123 (H2R123) and allowed us to resolve ROS responses to secretagogues, pyocyanin, and L-ornithine. Changes in the fluorescence of the new probe were particularly prominent in the peripheral plasma membrane-associated regions. Our findings suggest that the new probe will be a useful tool in studies of the contribution of ROS to the pathophysiology of exocrine pancreas and other organs/tissues.

Transmission of infection by flexible gastrointestinal endoscopy and bronchoscopy

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.

Bacteribilia with resistant microorganisms after preoperative biliary drainage--the influence of bacteria on postoperative outcome

BACKGROUND

In pancreatic surgery, preoperative biliary drainage (PBD) leads to bacteribilia. Whether positive bile duct cultures are associated with a higher postoperative morbidity might be related to the resistance of the species isolated from bile.

STUDY

Intraoperative bile duct cultures were collected from all patients who underwent pancreatic surgery. Postoperative morbidity was analyzed according to the species and the resistance found on bile duct cultures.

RESULTS

Fifty-five percent (166/301) of patients had PBD, while 45% (135/301) underwent primary operation. PBD was associated with a positive bile duct culture in 87% (144/166) versus 21% (28/135) in patients without PBD (p = 0.001) and polymicrobial infections in 53% (88/166) versus 6% (8/135) (p = 0.001). Postoperative morbidity was 40% (121/301); mortality was 3% (9/301). PBD was not associated with morbidity and mortality, but resistant species on bile duct cultures lead to significantly more postoperative complications, 54% (25/46) versus 38% (96/255) (p = 0.033), with significantly more antibiotic therapies.

CONCLUSION

PBD is associated with polymicrobial infections with resistant microorganisms, resulting in more postoperative complications. Since PBD cannot always be avoided, surgeons and gastroenterologists must be aware of their institutional surveillance data to identify patients at risk for postoperative complications.

Prophylactic antibiotics cannot prevent endoscopic retrograde cholangiopancreatography-induced cholangitis: a meta-analysis

OBJECTIVES

To determine the prophylactic effect of antibiotics on post-endoscopic retrograde cholangiopancreatography (ERCP) cholangitis or sepsis reduction in randomized controlled trials.

METHODS

Databases including MEDLINE, EMBASE, Cochrane Library, and Science Citation Index updated to June 2007 were searched. Main outcome measure was post-ERCP cholangitis or sepsis.

RESULTS

Seven trials were identified, and a total of 1389 patients were included; post-ERCP cholangitis occurred in 5.8% of controls (41/705) versus 3.4% of treated patients (23/684), without statistical significance (relative risk [RR], 0.58; 95% confidence interval [CI], 0.22-1.55). Subsequent sensitivity analysis on trials mainly targeted at patients with suspicious biliary obstruction showed that the incidences of post-ERCP cholangitis were 2.8% (12/425) and 5.4% (24/441) in the antibiotics and control groups, respectively, and this sensitivity analysis did not support antibiotics' preventive effect (RR, 0.33; 95% CI, 0.03-3.32). Another sensitivity analysis exclusively including trials with intravenous route of antibiotics administration also failed to confirm the prophylactic effect of antibiotics (RR, 0.53; 95% CI, 0.18-1.60).

CONCLUSIONS

Antibiotics cannot significantly prevent ERCP-induced cholangitis in unselected patients and should not be routinely recommended. Yet, more trials including patients with predicted incomplete biliary drainage are still required to prove the effectiveness of prophylactic antibiotics in this setting.

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.

Recommendations for antibiotic prophylaxis before ERCP: can we come to workable conclusions after review of the literature?

Infectious complications after endoscopic retrograde cholangiopancreatography (ERCP) are rare and can mainly be divided into endocarditis and sepsis/cholangitis. There still remains uncertainty about the indications, antibiotic regimens, and timing for antibiotic prophylaxis. Several guidelines for antibiotic prophylaxis have been published. It is the purpose of the present paper to make an extensive review of the literature and to yield general recommendations on antibiotic prophylaxis before ERCP. Antibiotic prophylaxis is recommended for patients at high risk for endocarditis, as well as for patients with a vascular graft less than 1 year old. For sepsis/cholangitis, prophylaxis is mostly recommended for patients with a bile duct obstruction or with a pancreatic pseudocyst. For other conditions, a case-by-case evaluation by the physician/endoscopist is still inevitable.

Multidrug-resistant Pseudomonas aeruginosa cholangitis after endoscopic retrograde cholangiopancreatography: failure of routine endoscope cultures to prevent an outbreak

BACKGROUND

Nosocomial infections due to medical devices are of increasing concern to infection control practitioners. Attempts to prevent such infections have included surveillance cultures of endoscopes and bronchoscopes. In July 2002, the infectious disease consultation service was asked to see three patients with sepsis due to multidrug-resistant Pseudomonas aeruginosa after endoscopic retrograde cholangiopancreatography (ERCP).

OBJECTIVE

To describe an outbreak of multidrug-resistant P. aeruginosa sepsis after ERCP at an institution that performs routine surveillance cultures of endoscopes.

DESIGN

A traditional outbreak investigation supplemented by pulsed-field gel electrophoresis (PFGE) was undertaken, including a case-control analysis based on the hypothesis that all infected individuals had their ERCP performed with the same endoscope.

SETTING

A tertiary-care academic medical center.

RESULTS

The case-control analysis confirmed the hypothesis that undergoing ERCP with the implicated endoscope was associated with a culture positive for Pseudomonas (P = .01). The available strains were identical by PFGE. This outbreak occurred despite a negative surveillance culture of the implicated endoscope 1 month earlier.

CONCLUSIONS

Infectious morbidity can occur after endoscopy despite negative surveillance cultures. The practice of routine endoscope cultures does not prevent device-related infectious morbidity.

The Occurrence and Prevention of Infections Associated with Gastrointestinal Endoscopy

In the four decades since the introduction of flexible endoscopy into medical practice, nearly 300 cases of human infections or pseudoinfections involving bacteria, fungi, parasites, and viruses have been linked to endoscopic procedures. In the majority of such cases, inadequate cleaning and disinfection techniques during the reprocessing of the instruments or their accessories have been likely contributing factors. Working groups from major gastroenterology societies and infection control organizations have established standards of care for the routine maintenance of endoscopic equipment in order to decrease the rates of infection even further. Since the institution of these standards, rates of transmission of infections to patients have decreased, though have not been completely resolved. This article reviews the available literature on transmission of pathogenic agents through endoscopic procedures, summarizes the current guidelines for the care of endoscopic equipment, and discusses available preventive measures aimed at decreasing the risk of endoscopy-related infections.

Incision and drainage of cutaneous abscesses is not associated with bacteremia in afebrile adults

STUDY OBJECTIVE

To determine the prevalence of bacteremia associated with incision and drainage (I&D) of cutaneous abscesses in afebrile adult emergency department patients. Such information has implications for the ED management of immunocompromised patients, patients with history of endocarditis, and patients with prosthetic appliances such as heart valves and artificial joints.

METHODS

We conducted a prospective clinical study in the adult ED of an urban tertiary care teaching hospital. Our subjects were afebrile patients aged 18 to 65 years with localized, nondraining, purulent cutaneous abscesses requiring outpatient surgical management. Before I&D, blood for aerobic and anaerobic blood culture was drawn under sterile conditions. The wound was opened and samples for aerobic wound culture were obtained. Two and 10 minutes after I&D, blood was again drawn, from separate venipunctures. All patients were discharged home with ED follow-up scheduled 48 hours later.

RESULTS

From the 50 patients who completed the study, 150 blood samples (50 before and 100 after I&D) and 50 wound samples were obtained. No blood culture was positive, but 30 wound cultures (64%) were positive; the most commonly isolated organism was Staphylococcus aureus.

CONCLUSION

I&D of localized cutaneous abscesses in afebrile adults is unlikely to result in transient bacteremia. Larger studies are needed to determine whether routine antibiotic prophylaxis is necessary for afebrile patients undergoing I&D.

Deficiencies of automatic endoscopic reprocessors: a method to achieve high-grade disinfection of endoscopes

BACKGROUND

We show that disinfection using the automatic endoscopic reprocessor is not complete and propose a method for high-grade disinfection of endoscopes.

METHODS

We used an automatic endoscopic reprocessor, Pyser System 83, and 2% glutaraldehyde. After each endoscopic procedure, the endoscopes were divided into three groups. Endoscopes in group A were washed only by the reprocessor. Group B endoscopes were washed by the reprocessor after the connectors were soaked in glutaraldehyde for 5 minutes. The channels, valves, connecting sections of group C endoscopes, and the connectors of the machine were sprayed with glutaraldehyde before machine-washing. Swabs were taken from all 13 parts of each endoscope and machine for microbiologic culture.

RESULTS

Six endoscopes were positive, cumulatively, for bacterial contamination in group A. Among group B endoscopes, one remained contaminated. No endoscope was positive in group C. The difference between group A and C was statistically significant (p < .05).

CONCLUSIONS

Machine washing by automatic endoscopic reprocessors may not achieve complete disinfection. Additional procedures are necessary. High-grade disinfection of the connectors is critical. Disinfection of the interface between the connectors is important.

Prophylactic antibiotic treatment in therapeutic or complicated diagnostic ERCP: results of a randomized controlled clinical study

The present study evaluated the effects of prophylactic administration of cefotaxime in patients undergoing therapeutic or complicated diagnostic ERCP. One hundred patients were randomized to two groups of 50 patients each. Patients in group 1 received an intravenous infusion of 2 g cefotaxime 15 minutes before endoscopy; patients in group 2 did not receive an intravenous antibiotic before ERCP (control group). Blood samples were drawn for bacteriologic cultures before endoscopy and 5, 15, 30, and 120 minutes after beginning the procedure. Bacteremia was detected by blood cultures (15- and 30-minute samples) in 4 patients who did not receive prophylactic antibiotics (Escherichia coli in 2 cases, Peptostreptococcus in 1, and Staphylococcus aureus in 1). Cholangitis or sepsis did not occur after the bacteremic episodes in any of these patients. In 4 other patients who did not receive cefotaxime-all of whom had biliary obstruction-clinical cholangitis or sepsis developed during the 3-day follow-up; ERCP had failed to decompress the biliary system completely in these 4 cases. Blood cultures identified bacteria in 3 of these 4 patients (Pseudomonas aeruginosa in 1, E. coli in 2). Thus, bacteremia or clinical sepsis developed in 8/50 patients (16%) in the control group without antibiotic prophylaxis, whereas no such episode was observed in patients who had received prophylactic treatment (chi 2 = 8.7; p < 0.01). The present results indicate that prophylactic administration of an antibiotic such as cefotaxime can reduce the incidence of bacteremia and sepsis in patients who undergo therapeutic or complicated diagnostic ERCP.(ABSTRACT TRUNCATED AT 250 WORDS)

Pseudomonas aeruginosa and Enterobacteriaceae bacteremia after biliary endoscopy: an outbreak investigation using DNA macrorestriction analysis

PURPOSE

An outbreak of gram-negative bacteremia in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) was investigated to determine the sources of infection and to control transmission.

PATIENTS, METHODS, AND RESULTS

The incidence of post-ERCP bacteremia increased from 1.6% (60 of 3,696) procedures to 3.6% (53 of 1,454) procedures (relative risk 2.3, p < 0.0001) after endoscopes were processed in a new automated disinfector. Bacteremia involved nine species of Pseudomonas and Enterobacteriaceae, which were also isolated from processed endoscopes. Seven epidemic strains with highly related genomic macrorestriction profiles each infected 2 or more patients, accounting for 29 (55%) episodes of post-ERCP bacteremia. Strains recovered from endoscopes and from the disinfector were associated with 22 (42%) and 5 (9%) bacteremic episodes respectively. Effective endoscope disinfection was achieved by cleansing and disinfection of a blind channel not processed in the disinfector, additional isopropanol-air flush of all channels, and auto-disinfection of the disinfector. In the following period, the incidence of post-ERCP bacteremia returned to the pre-epidemic rate (1.7%, p = 0.0001).

CONCLUSION

Bacterial genome fingerprinting by macrorestriction analysis enabled delineation of a multi-strain outbreak of post-ERCP bacteremia. Cross-contamination, and to a lesser extent, common-source contamination, appeared related to inadequate disinfection of endoscopes processed in an automated disinfector.

Bacteremia following diagnostic and therapeutic ERCP

The occurrence of bacteremia in association with diagnostic or therapeutic ERCP was studied in 180 patients undergoing a total of 194 examinations. Nineteen (15%) of 126 diagnostic procedures and 18 (27%) of 68 therapeutic procedures were associated with bacteremia (p less than 0.1). Nine patients had polymicrobial bacteremia and a total of 16 species were detected. Different streptococci, mainly alpha-hemolytic, were the most common bacteria which were identified in 38% of the bacteremic patients. There were no significant differences with regard to the occurrence of fever, pancreatitis, or septic complications between the diagnostic and therapeutic groups of patients. Neither did the complication rate in patients with bacteremia differ from that in patients without bacteremia, whether the procedure was diagnostic or therapeutic. Complication rates did not differ between patients with and patients without pancreaticobiliary obstruction. However, the majority of patients with biliary stasis had drainage with relief of the obstruction at the time of the diagnostic ERCP. We conclude that general routine antibiotic prophylaxis is not indicated in patients undergoing diagnostic or therapeutic ERCP. The question whether such prophylaxis should be given with certain diagnoses or treatments, or in patients with valvular heart disease, remains to be answered in controlled randomized studies.

Infection and endoscopy: who infects whom?

Infection is one of the major hazards of endoscopic procedures and is the commonest complication of endoscopic retrograde cholangio-pancreatography (ERCP) causing death. Prevention of endoscopy-associated infections is based on adequate cleaning and disinfection regimens. Scrupulous mechanical cleaning is fundamental; even prolonged chemical disinfection will be ineffective if cleaning has not been adequate. Special measures are required to prevent ERCP-related infections. It is important to recognize various special circumstances that increase a patient's susceptibility to infection and to administer antibiotic prophylaxis when appropriate.

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.

Urgent biliary decompression after endoscopic retrograde cholangiopancreatography

Acute cholangitis complicating diagnostic endoscopic retrograde cholangiopancreatography (ERCP) is potentially fatal. Among 323 consecutive patients with proved biliary obstruction, 21 (7 percent) developed acute cholangitis after examination. Four patients underwent emergency surgery for the control of sepsis with two deaths. Of the 21 parameters chosen for evaluation, malignant obstruction, fever (higher than 37.5 degrees C) within 72 hours before the procedure or when afebrile, and an increased aspartate transaminase level of 70 IU or more were the independent predictive factors identified by multivariate analysis. An increased temperature should be regarded as an absolute contraindication to examination unless followed by immediate ductal drainage. Since the risk of septic complications is minimal when none of the risk factors are present, routine urgent biliary decompression after ERCP is probably unnecessary for these selected patients. For patients with malignant obstruction or other risk factors, early elective surgical drainage is advisable. When surgery is not feasible, nonoperative drainage of the obstructed biliary system as a preventive measure might be considered.

Diagnosis of cholestasis: an analytic view

The authors analyzed two invasive procedures used to visualize the biliary tree, endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC), and also explored the utility of preinvasive workups for patients with suspected cholestasis. For this analysis they used published ranges for success, fatality, complications, diagnostic accuracies of the procedures, and prognostic information about the underlying diseases. The choice between ERCP and PTC was found to be a "close call," but ERCP was generally favored as the first-choice procedure. The results suggest that noninvasive imaging does not help decide between ERCP and PTC. Although noninvasive imaging may identify those patients with common duct dilation, the higher success rate with PTC in these patients is offset by a slightly higher mortality rate. Consequently, the choice between ERCP and PTC remains close even if ultrasound has shown that biliary ducts are dilated. Furthermore, it is shown that these noninvasive tests are most useful when they can conclusively determine the presence or absence of biliary obstruction. For many patients, noninvasive imaging will not obviate the need for invasive tests.

Serious Pseudomonas infections associated with endoscopic retrograde cholangiopancreatography

After observing a single case of Pseudomonas aeruginosa bacteremia following endoscopic retrograde cholangiopancreatography (ERCP), six other P. aeruginosa infections that were temporally related to ERCP were retrospectively found over one year (August 1985 through July 1986) at LDS Hospital. In all seven patients, infection developed within five days after an ERCP. Five patients had bacteremia and two had cholangitis. All five of the Pseudomonas isolates available for testing were serotype 010. Cultures from the ERCP endoscope and several other endoscopes also yielded P. aeruginosa serotype 10, as did environmental cultures from equipment used to clean endoscopes. Among 167 ERCPs performed during the outbreak period, no other patient acquired P. aeruginosa infection. Each of the patients in the outbreak received the first scheduled ERCP of the day. The mean duration between the cleaning of the ERCP endoscope and its subsequent use was significantly longer in cases than in matched controls, a factor that may have permitted contaminating organisms to achieve high inocula in the inadequately cleaned endoscope. Epidemic control measures included improved disinfection of endoscopes, ongoing surveillance, and appropriate antimicrobial prophylaxis. This experience suggests that exogenous infection with Pseudomonas is associated with ERCP, that protracted and insidious outbreaks may occur, and that the occurrence of even a single case of Pseudomonas infection after ERCP should stimulate an epidemiologic investigation.

Prospective assessment of risk of bacteremia with colonoscopy and polypectomy

A prospective assessment was made of the frequency of positive blood cultures in patients undergoing colonoscopy with or without polypectomy. A total of 270 patients underwent 280 colonoscopies, of these, there were 105 patients that had 111 polypectomies. Blood cultures were taken prior to and within 15 min following each procedure. Six of 280 (2.1%) preprocedural blood cultures were positive. Seven of 169 (4%) blood cultures were positive within 15 min of insertion of the colonoscope in the colonoscopy only group. Eight of 223 (3.6%) blood cultures were positive within 10 min of the polypectomy. There was no clinical evidence of sepsis during the 24 hr following these procedures. In order to determine appropriate postprocedural sampling intervals, we induced a Staphylococcus epidermidis bacteremia with a mean of 1.16 X 10(6) colony forming units/ml on 10 occasions in seven dogs. Within 30 min of inoculation, we were able to detect only one colony forming unit/ml. The rate of positive blood cultures during colonoscopy alone and following polypectomy during colonoscopy is comparable to other gastrointestinal endoscopy procedures. The most optimal time to collect blood cultures in order to detect transient bacteremia is as soon after the procedure as is feasibly possible.

Pseudomonas aeruginosa liver abscesses following endoscopic retrograde cholangiography. Report of a case without biliary tract disease

We report a case of Pseudomonas aeruginosa liver abscesses following endoscopic retrograde cholangiopancreatography (ERCP) in a patient without evidence of biliary tract disease and of any known cause of hepatic infection. Computer tomography (CT) scan was the best method of diagnosis, allowing, through guided percutaneous puncture of the abscesses, isolation of the organism, which was sensitive to carbenicillin. One month of antibiotherapy with repeated aspirations of the largest abscesses was successful. This report suggests that ERCP may induce cholangitic sepsis by inoculating pathogens in the biliary tree even in the absence of extrahepatic obstruction.

Pseudomonas infection of the biliary system resulting from use of a contaminated endoscope

Pseudomonas aeruginosa was present in bile cultures from 10 patients who had undergone previous endoscopic retrograde cholangiopancreatography in 1984. After environmental cultures and review of instrument disinfection, we traced the infections to a single endoscope contaminated with P. aeruginosa, serotype 10. Although the instrument had been cleaned repeatedly with an automatic endoscope cleaning machine, P. aeruginosa survived on residual moisture left in the channels of the endoscope. Contamination ended only after we began to manually suction alcohol through the endoscope before air drying. In 5 of 10 patients, P. aeruginosa caused clinical infections including gangrenous cholecystitis, abscesses, and death. We could identify no factor that distinguished symptomatic from asymptomatic patients. In asymptomatic patients, P. aeruginosa was recovered from gallbladder bile up to 2 mo after endoscopic retrograde cholangiopancreatography. As this P. aeruginosa epidemic was discovered retrospectively because we monitor bile cultures, we advocate this practice as part of endoscopic retrograde cholangiopancreatography procedures.

Bacteremia with gastrointestinal endoscopic procedures

The authors have reviewed 40 prospective studies of bacteremia with gastrointestinal procedures. Endoscopic procedures with a low mean frequency of bacteremia were esophagogastroduodenoscopy (4.2%), endoscopic retrograde cholangiopancreatography (5.6%), colonoscopy (2.2%), and sigmoidoscopy (4.9%). A higher mean frequency of bacteremia was encountered with esophageal dilation (45%) and variceal sclerotherapy (31%), although the number of patients studied was small. Potentially pathogenic organisms, such as Streptococcus viridans, Staphylococcus aureus, and Staphylococcus epidermidis have been isolated. Recommendations for antibiotic prophylaxis are reviewed. Less cumbersome regimens encourage compliance and are preferred.

Bacteremia during esophageal variceal sclerotherapy: its cause and prevention

Eleven consecutive patients underwent a total of 34 esophageal variceal sclerotherapy (EVS) sessions for bleeding esophageal varices. Blood cultures were drawn pre-, intra-, and post-EVS. All pre- and post-EVS blood cultures were negative. Five of the initial nine patients studied were found to have positive blood cultures, drawn after a mean of six injections. Pseudomonas aeruginosa was cultured from the blood in four patients and Flavobacterium from one. The source of contamination was found to be contaminated water used during the sclerotherapy sessions. By instituting simple techniques to eliminate this contamination, patients undergoing the remaining 25 EVS sessions were culture negative.

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).

Pseudomonas aeruginosa sepsis following retrograde cholangiopancreatography (ERCP)

Endoscopic retrograde cholangiopancreatography (ERCP) has become a routine examination in a number of medical centers within the past several years. We report a life-threatening case of acute pancreatitis with Pseudomonas aeruginosa sepsis immediately following ERCP. Cultures of the blood, the inner channel of the duodenoscope, and irrigating water bottles all were positive for Pseudomonas aeruginosa. The Pseudomonas aeruginosa isolated from the blood and endoscope both reacted to three common antisera: serotypes 2, 15, and 16, suggesting a common source of infection. Although it is obvious that the ERCP procedure cannot be sterile, attempts should be made to prevent transmission of nosocomial pathogens by this procedure.