Single-use duodenoscopes compared with reusable duodenoscopes in patients carrying multidrug-resistant microorganisms: a break-even cost analysis.

Background and study aims Single-use duodenoscopes can prevent transmission of microorganisms through contaminated reusable duodenoscopes. Concerns regarding their economic and environmental impact impede the transition to single-use duodenoscopes. This study investigated the costs associated with two scenarios in which single-use duodenoscopes are used in patients carrying multidrug-resistant microorganisms (MDROs). Methods Break-even costs for single-use duodenoscopes were calculated for two scenarios in which patients were screened for MDRO carriage before undergoing endoscopic retrograde cholangiopancreatography (ERCP). Only direct costs related to the endoscopy were taken into consideration. In Scenario 1, patients were screened through microbiological culturing with a lag time in receiving the test result. In Scenario 2, screening was performed using GeneXpert analysis providing a rapid read-out. Calculations were performed using data from a Dutch tertiary care center and also with US healthcare data. Results In the Dutch situation, single-use duodenoscopes needed to be priced at a maximum of €â€Š140 to €â€Š250 to break-even. In the US analyses, break-even costs varied widely, depending on the duodenoscope-associated infection costs used, ERCP volume, and infection risk. The break-even costs in Scenario 1 ranged between $78.21 and $2,747.54 and in Scenario 2, between $248.89 and $2,209.23. Conclusions This study showed that a crossover scenario in which single-use duodenoscopes are only used in patients carrying MDROs could be an economically viable alternative to a complete transition to single-use duodenoscopes. In the Dutch setting, single-use duodenoscopes need to be priced much lower than in the United States to reach a per-procedure cost that is comparable with a scenario using reusable duodenoscopes exclusively.

Investigation of the efficacy of an innovative endoscope drying and storage method in a simulated ERCP setting.

Background and study aims Drying after cleaning and disinfection is essential in the reprocessing of endoscopes since microorganisms can grow and form biofilms on wet surfaces. In this experimental non-clinical study, we investigated the efficacy of a novel, fast-drying method when reprocessing duodenoscopes. Methods During a series of 40 tests, three duodenoscopes were exposed to an artificial test soil containing supraphysiological loads of four types of gut microorganisms in a non-clinical ERCP simulation, followed by reprocessing and drying with the PlasmaTYPHOON. Cultures of the distal tip and working channel were acquired immediately after automated decontamination and after drying with the PlasmaTYPHOON. Cobalt chloride paper tests and borescope inspections were used to evaluate drying efficacy. Results Contamination of the working channels dropped from 86.4 % post-decontamination to 33.6 % post-drying, with 94 % of the positive post-drying samples belonging to one duodenoscope. This duodenoscope showed persistent contamination with P. aeruginosa in the working channel. The other two duodenoscopes only showed low levels of P. aeruginosa in post-decontamination channel samples, but not after drying. Cobalt chloride paper tests and borescope inspections revealed good drying efficacy. Conclusions Positive cultures for gut microorganisms were often found in wet endoscopes post-decontamination. The PlasmaTYPHOON is an effective fast-drying method capable of abolishing nearly all remaining microorganisms after decontamination provided no biofilm has developed, even when using a supraphysiological concentration of bacterial load. The clinical use of the PlasmaTYPHOON has the potential to reduce endoscope contamination, the use of wet contaminated endoscopes and therefore the risk of patient infection.

No relation between adenosine triphosphate after manual cleaning and presence of microorganisms on endoscopes after automated high-level disinfection.

Background and study aims Adenosine triphosphate (ATP) tests are increasingly used to detect biological material; however, their reliability to detect bacterial contamination in endoscopes is not proven. We investigated the predictive value of ATP tests after manual cleaning for presence or absence of microorganisms as shown by culture after automated high-level disinfection (HLD) in duodenoscopes and linear echoendoscopes (DLEs). Patients and methods After manual cleaning, ATP tests were performed on swab samples taken from the detachable cap and forceps elevator, and on flush samples of the DLE working channels. These results were compared to the growth of any microorganisms in cultures acquired after automated HLD. ATP tests with > 200 relative light units (RLU) were considered positive. Receiver operator characteristic (ROC) curves were used to compare the RLU levels with microbial presence in cultures. Results In total, 903 procedures were performed involving 26 distinct DLEs. Depending on sample site, 20.8 % (cap) to 63.8 % (channel brush) of the ATP negative samples were accompanied by positive post-HLD cultures. 54.4 % of the cap samples with a positive culture (growth of any kind of microorganism) and 91.8 % of the channel samples with a positive culture had a negative ATP test after manual cleaning. ROC curves per sample site, DLE type and microorganism type all had area under the curves below 0.6. Conclusions In our study, ATP tests performed after manual cleaning could not predict presence or absence of microorganisms after automated HLD as shown by culture. More than half of the positive cultures were preceded by a negative ATP test.

Persistent contamination of a duodenoscope working channel in a non-clinical simulated ERCP setting.

BACKGROUND: To mitigate duodenoscope contamination, recent design enhancements have primarily focused on the distal tip. However, the working channels remain unchanged, which may be linked to biofilm formation. We assessed the persistence of microorganisms, indicative of biofilm formation, in reprocessed duodenoscopes in a non-clinical endoscopic retrograde cholangiopancreatography (ERCP) simulation setting. METHODS: Three new duodenoscopes were over-soiled in non-clinical ERCP simulations followed by reprocessing. After 40 tests, the Pseudomonas aeruginosa strain in the soil (Pa-type 1) was switched to a different P. aeruginosa strain (Pa-type 2) for 20 subsequent tests. Cultures of the tip and working channel were acquired after high level disinfection and overnight storage. RESULTS: One duodenoscope showed persistent growth of P. aeruginosa from the fifth test until the end of the study. Pa-type 1 remained present until the end of the study in the cultures of this duodenoscope, even after discontinuation of exposure to that specific strain. The other two duodenoscopes only showed incidental contamination. CONCLUSION: Persistent contamination by Pa-type 1 was seen in one out of three duodenoscopes after exposure to supraphysiological levels of gut microorganisms. No clear explanation was found for this persistent contamination as exposure and handling were identical and no abnormalities of this particular duodenoscope were identified by borescope inspection.

Risk evaluation of duodenoscope-associated infections in the Netherlands calls for a heightened awareness of device-related infections: a systematic review.

BACKGROUND: The risk of exogenous infections from endoscopic procedures is often cited as almost negligible (1 infection in 1.8 million procedures); however, this risk is based on older literature and does not seem to match the number of infectious outbreaks due to contaminated duodenoscopes reported after endoscopic retrograde cholangiopancreatography (ERCP). Using Dutch data, we aimed to estimate the minimum risk of duodenoscope-associated infection (DAI) and colonization (DAC) in patients undergoing ERCP. METHODS: A systematic literature search identified all DAI outbreaks in the Netherlands reported between 2008 and 2019. Included cases were confirmed by molecular matching of patient and duodenoscope cultures. Risk ratios were calculated based on the total number of ERCPs performed during the study period. RESULTS: Three outbreaks were reported and published between 2008 and 2018, including 21 confirmed DAI cases and 52 confirmed DAC cases. The estimated number of ERCPs performed during the same period was 181 209-227 006. The calculated minimum estimated DAI risk was approximately 0.01 % and the minimum estimated DAC risk was 0.023 %-0.029 %. CONCLUSIONS: The estimated risk of DAI in Dutch ERCP practice was at least 180 times higher than previously published risk estimates. The actual risk is likely to be (much) higher due to underreporting of infections caused by multidrug-resistant organisms and sensitive bacteria. Greater awareness by healthcare personnel involved in endoscopy and endoscope cleaning is required, as well as innovative technical solutions to contain and ultimately eliminate DAIs.

Investigation of possible transmission of a susceptible microorganism through a contaminated duodenoscope; a case report.

BACKGROUND: Despite compliance to extensive reprocessing protocols, duodenoscopes have been linked to outbreaks of susceptible and multi-drug resistant organisms (MDRO) due to persistent duodenoscope contamination. Duodenoscope-associated infections (DAIs) based on transmission of susceptible microorganisms are likely to be underreported due to detection bias. CASE PRESENTATION: We describe the retrospective detection of a DAI case caused by a susceptible microorganism which at the time of clinical infection was not recognized as such. During 2017 and 2018, duodenoscopes were cultured on a daily basis due to research activities. While analyzing this data, it was found that a duodenoscope had been contaminated with Enterobacter cloacae complex over a period of 3 months. We checked whether patients treated with this duodenoscope had developed infections and found one patient with an E. cloacae cholangitis 3 months after the ERCP (Endoscopic retrograde cholangiopancreaticography) procedure. The isolates on the duodenoscope and in the patients' blood culture were indistinguishable by amplified fragment length polymorphism (AFLP). By classical multi-locus sequence typing (MLST), both strains were of the same (but novel) sequence type. Application of whole genome MLST showed 93 (out of 3757) allelic differences. CONCLUSION: This case report describes a plausible link between a contaminated duodenoscope and a patient infection with E. cloacae. Transmission of susceptible E. cloacae was highly suspected from AFLP and MLST results; by WGS, 93 allelic differences were found which proves closely related strains. This report shows that DAIs by susceptible microorganisms can be easily missed and therefore its true prevalence remains underscored.

The difference in endoscopic yield in patients with either iron-deficiency anemia or anemia with normal ferritin.

OBJECTIVE: Current guidelines recommend a gastroduodenoscopy (GDS) and colonoscopy in patients with iron-deficiency anemia (IDA). However, in daily practice, patients with nonferriprive anemia are also referred for endoscopy. The aim of this study is to compare the diagnostic yield of colonoscopy and GDS in patients with IDA and non-IDA. PATIENTS AND METHODS: A retrospective single-center cohort study was carried out from January 2013 till February 2016 that included 917 patients with anemia. We compared the endoscopic yield in patients with IDA versus patients with anemia otherwise. Multivariate regression analyses were carried out to identify predictive factors for the diagnostic yield of GDS and colonoscopy. RESULTS: The yield of both GDS (25%) and colonoscopy (30%) was comparable in IDA and non-IDA patients. However, in patients without known gastrointestinal medical history and without concomitant indications for endoscopy (N=373), the diagnostic yield of GDS was three times higher in IDA patients compared with non-IDA patients (P<0.01). The diagnostic yield for colonoscopy was not significantly different between the two groups. Age and sex were recurrent predictive variables in the outcome of both GDS and colonoscopies. CONCLUSION: We recommend IDA as well as non-IDA as indications for GDS and colonoscopy. Only in patients without gastrointestinal history or localizing complaints a significant difference in the diagnostic yield is found between IDA and non-IDA patients. In this group, upper endoscopy can be omitted in non-IDA patients as they were three times less likely to have a bleeding source found on GDS compared with IDA patients.