Ausbruch mit Burkholderia-cepacia-Komplex durch kontaminierte Mundspüllösung

Two consecutive outbreaks caused by chlorhexidine mouthwash contaminated with Burkholderia contaminans in a two-hospital tertiary care system

BACKGROUND

Hospital outbreaks caused by Burkholderia spp. have been linked to contamination of several medical solutions and products and are frequently associated with delayed detection and high mortality.

AIM

To describe the management of two consecutive Burkholderia contaminans outbreaks caused by contaminated mouthwash of different brands during the COVID-19 pandemic.

METHODS

This was a retrospective cohort study of all patients involved in two outbreaks caused by B. contaminans detected in 2021 and 2022. The investigation was initiated after a cluster of positive respiratory specimens, followed by retrospective and prospective case-finding.

FINDINGS

A total of 69 patients were affected, 47 in 2021 and 22 in 2022. The majority of affected patients had positive respiratory specimens (85.5%); 55.1% of cases had COVID-19, and 72.5% had multidrug-resistant organisms. Almost all (97.1%) patients required ventilation and 42.0% died. Seventeen percent of cases in the first outbreak were deemed to have been acquired by patient-to-patient transmission, whereas all of the cases in the second outbreak were infected directly from using mouthwash. The experience gained from the first outbreak and the formation of a multidisciplinary Infection Control Rapid Response Team resulted in more rapid recognition and control of the second outbreak. Multivariate analysis showed that older age, intensive care unit admission, and COVID-19 infection were independent predictors of mortality.

CONCLUSION

Burkholderia outbreaks at the time of COVID-19 were associated with high mortality. Rapid detection and response by a dedicated experienced team (as in the second outbreak) can reduce mortality and prevent superimposed cross-transmission between patients.

Soleris® Automated System for the Rapid Detection of Burkholderia cepacia Complex in Cosmetic Products

BACKGROUND

Burkholderia cepacia complex (Bcc) has emerged as an important opportunistic pathogen with rising concern in pharmaceuticals and cosmetic products. The Bcc supplement (S2-BCC-S) was purposely developed and used with the Pseudomonas vial (PD-109) for the detection of Bcc through the Soleris® Next Generation automated instrument system.

OBJECTIVE

This study aimed to evaluate the performance of the Soleris Bcc testing method for cosmetic products.

METHOD

Inclusivity and exclusivity were assessed with the Soleris Bcc method and the United States Pharmacopeia (USP) method in three enrichment broths. Matrix testing was conducted using 28 cosmetic products to compare the equivalency of the Soleris Bcc method to that of the USP reference method. Repeatability of the Soleris Bcc assay, method robustness, product stability, and lot-to-lot consistency of the Soleris reagents were also assessed.

RESULTS

Both the Soleris Bcc and the USP methods supported the growth of all 26 inclusivity strains, except the USP method missed one inclusivity strain in one broth. For exclusivity, 0-6% was presumptive positive with the Soleris Bcc method, and 42-48% was presumptive positive with the reference method. Kappa index was 0.96 for the matrix testing, indicating a good agreement between the Soleris Bcc assay and the reference method for testing Bcc in cosmetics. Repeatability results showed the coefficient of variation was less than 4%. The robustness and ruggedness study yielded detection times within 1 h differences when small variations were introduced. The lot-to-lot study showed consistent results among four lots of the Bcc reagents.

CONCLUSIONS

The automated Soleris method was successfully demonstrated to be robust, sensitive, and specific for Bcc detection in cosmetic products.

HIGHLIGHTS

The Soleris Bcc method is user-friendly. It shows the results in real time and generates the report automatically. Implementation of this method for detection of Bcc in cosmetics would save significant time and resources.

Combined clinical, epidemiological and genome-based analysis identified a nationwide outbreak of Burkholderia cepacia complex infections caused by contaminated mouthwash solutions

Background

In September 2018, Burkholderia cepacia complex (BCC) infections in 3 patients associated with exposure to a mouthwash solution (MWS) were reported to the Robert Koch Institute (RKI). As the product was still on the market and the scale of the outbreak was unclear, a nation-wide investigation was initiated.

Methods

We aimed to investigate BCC infections/colonizations associated with MWS. Hospitals, laboratories, and public health services were informed that BCC isolates should be sent to the RKI. These isolates were typed by pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS) including development of an ad hoc core genome MLST (cgMLST) scheme.

Results

In total, 36 patients from 6 hospitals met the case definition, the last patient in November 2018. Twenty-nine isolates from 26 of these patients were available for typing. WGS analysis revealed 2 distinct cgMLST clusters. Cluster 1 (Burkholderia arboris) contained isolates from patients and MWS obtained from 4 hospitals and isolates provided by the manufacturer. Patient and MWS isolates from another hospital were assigned to cluster 2 (B. cepacia).

Conclusions

The combined clinical, epidemiological, and microbiological investigation, including whole-genome analysis, allowed for uncovering a supraregional BCC outbreak in health care settings. Strains of B. arboris and B. cepacia were identified as contaminating species of MWS bottles and subsequent colonization and putative infection of patients in several hospitals. Despite a recall of the product by the manufacturer in August 2018, the outbreak lasted until December 2018. Reporting of contaminated medical products and recalls should be optimized to protect patients.

Global burden, point sources, and outbreak management of healthcare-associated Burkholderia cepacia infections: An integrative review

OBJECTIVE

To examine the global burden, associated point sources, and successful prevention and control measures for documented outbreaks of Burkholderia cepacia healthcare-associated infections (HAIs).

DESIGN

Integrative review.

METHODS

A review of all outbreaks of Burkholderia cepacia HAIs published in the peer-reviewed literature between January 1970 and October 2019 was conducted to identify the global burden, associated point sources, and successful prevention and control measures using the Guidelines for Outbreak Reports and Intervention Studies of Nosocomial Infections (ORION).

RESULTS

In total, we reviewed 125 documented outbreaks of Burkholderia cepacia-related HAIs worldwide. The reported B. cepacia HAIs for this period involved 3,287 patients. The point sources were identified in most outbreaks of B. cepacia HAIs (n = 93; 74.4%); they included medication vials, disinfectants, and antiseptics. Moreover, 95 of the outbreak reports (76%) described effective prevention and control measures, but only 33 reports indicated the use of a combination of environment-, patient- and staff-related measures. None of the outbreak reports used the ORION guidelines.

CONCLUSIONS

Outbreaks of Burkholderia cepacia HAIs are an ongoing challenge. They are often associated with immunocompromised patients who acquire the infection from exposure to contaminated medications, products, and equipment. These outbreaks are not infrequent, and a range of infection prevention and control measures have been effective in arresting spread. The use of ORION guidelines for outbreak reporting would improve the quality of information and data to generate evidence for translation into practice.

Consecutive outbreaks of Burkholderia cepacia complex caused by intrinsically contaminated chlorhexidine mouthwashes

BACKGROUND

We report 2 consecutive outbreaks of the Burkholderia cepacia complex (Bcc) in an intensive care unit (ICU) and describe its characteristics and consequences.

METHODS

Over a 72-day period, a multidisciplinary ICU team detected 2 distinct periods of high and unusual incidence of Bcc isolates that were recovered from cultures of endotracheal aspirate. Cultures of tap water, ultrasound gel and mouthwash (opened and unopened bottles) were performed. Bcc was identified with the BD-Phoenix and MALDI-TOF MS systems, with molecular typing using the enterobacterial repetitive intergenic consensus-polymerase chain reaction technique.

RESULTS

In both outbreak 1 (6 patients) and outbreak 2 (5 patients), the point sources of Bcc were chlorhexidine mouthwashes of 2 different brands, both of them intrinsically contaminated. All patients had a clinical diagnosis of ventilator-associated pneumonia (VAP), and 6 died. MALDI-TOF MS identified 2 species of Bcc (B. cenocepacia and B. cepacia). Enterobacterial repetitive intergenic consensus-polymerase chain reaction typing confirmed 100% genetic similarity between patient and mouthwash isolates from each period. The first outbreak was controlled in 20 days and the second in 6 days.

CONCLUSIONS

The surveillance program for multidrug-resistant organisms, especially in high-risk patients, with the active participation of a multidisciplinary team, was crucial for success in controlling these outbreaks.

Outbreak of Burkholderia cepacia complex infections associated with contaminated octenidine mouthwash solution, Germany, August to September 2018

Three German patients developed nosocomial pneumonia after cardiac surgery and had Burkholderia cepacia complex detected in respiratory specimens. Two patients died of septic multi-organ failure. Whole-genome sequencing detected genetically identical B. cepacia complex strains in patient samples, from a batch of octenidine mouthwash solution, which had been used for nursing care, as well as in samples obtained from the manufacturer during production. Contamination of medical products during manufacturing may lead to international outbreaks.

Microbiological Safety of Non-Food Products: What Can We Learn from the RAPEX Database?

For consumer protection across borders, the European Union has established the rapid alert system for dangerous non-food products (RAPEX), with the overarching goal of preventing or limiting the sale and use of non-food products that present a serious risk for the health and safety of consumers. In our study, we comprehensively analyzed RAPEX notifications associated with products posing a microbiological risk from 2005 through 2017. Additional information was retrieved from national laboratory reports. A total of 243 microbiologically harmful consumer products triggered notifications in 23 out of 31 participating countries. About half of the products were reported by Spain, Germany, and Italy. Notifications mainly included contaminated toys, cosmetics, and chemical products. Depending on the notifying country, measures taken to prevent the spread of dangerous products were predominantly ordered either by public authorities or economic operators. The interval between microbiological diagnosis and the date of RAPEX notifications considerably varied between RAPEX member states, ranging between a few days and 82 weeks. The nature and extent of RAPEX usage substantially differed among member states, calling for harmonization and optimization. Slight modifications to RAPEX could help to systematically record microbiological hazards, which may improve the assessment of potential health risks due to contaminated non-food products.

Reduction of nosocomial bloodstream infections and nosocomial vancomycin-resistant Enterococcus faecium on an intensive care unit after introduction of antiseptic octenidine-based bathing

BACKGROUND

Vancomycin-resistant Enterococcus faecium (VRE) is emerging in German intensive care units (ICUs). On a 32-bed surgical ICU at a university hospital, increasing numbers of nosocomial cases occurred despite enforcement of hand hygiene and environmental disinfection.

AIM

To introduce universal octenidine-based bathing in order to reduce the burden of VRE.

METHODS

Between January 2012 and March 2014, patients were screened for VRE on admission and twice weekly. Active surveillance was undertaken for VRE infections and colonizations, and for bloodstream infections (BSI) with any pathogen. Intervention in this before-after study comprised of standardized octenidine-based bathing. Distinct subgroups of VRE colonizations or infections were defined and used for statistical analysis of frequency, prevalence and incidence density.

FINDINGS

In the pre-intervention period (January 2012 to April 2013), the admission prevalence of VRE was 4/100 patients and the mean incidence density of nosocomial cases was 7.55/1000 patient-days (PD). Pulsed-field gel electrophoresis analysis revealed prevalence of three vanA and two vanB clusters. In the post-intervention period (August 2013 to March 2014), the admission prevalence of VRE was 2.41/100 patients and the mean incidence density of nosocomial cases was 2.61/1000 PD [P = 0.001 (pre- vs post-intervention)]. Thirteen nosocomial VRE infections were identified in the pre-intervention period, compared with one nosocomial VRE infection in the post-intervention period. Incidence densities of BSI pre- and post-intervention were 2.98 and 2.06/1000 PD (P = 0.15), respectively.

CONCLUSION

The epidemiology of emerging VRE appeared as a complex mix of admitted cases and transmissions in small clusters, challenging infection control measures. The implementation of universal octenidine-based bathing combined with a standardized washing regime led to a significant reduction in nosocomial VRE.

Burkholderia stabilis outbreak associated with contaminated commercially-available washing gloves, Switzerland, May 2015 to August 2016

We describe an outbreak of Burkholderia stabilis associated with contaminated washing gloves, a commercially available Class I medical device. Triggered by an increase in Burkholderia cepacia complex (BCC) bacteremias and the detection of BCC in unopened packages of washing gloves, an ad hoc national outbreak committee comprising representatives of a public health organisation, a regulatory agency, and an expert association convened and commissioned an outbreak investigation. The investigation included retrospective case finding across Switzerland and whole genome sequencing (WGS) of isolates from cases and gloves. The investigation revealed that BCC were detected in clinical samples of 46 cases aged 17 to 91 years (33% females) from nine institutions between May 2015 and August 2016. Twenty-two isolates from case patients and 16 from washing gloves underwent WGS. All available outbreak isolates clustered within a span of < 19 differing alleles, while 13 unrelated clinical isolates differed by > 1,500 alleles. This BCC outbreak was rapidly identified, communicated, investigated and halted by an ad hoc collaboration of multiple stakeholders. WGS served as useful tool for confirming the source of the outbreak. This outbreak also highlights current regulatory limitations regarding Class I medical devices and the usefulness of a nationally coordinated outbreak response.

Evaluating the use of whole-genome sequencing for outbreak investigations in the lack of closely related reference genome

Whole-genome sequencing (WGS) has emerged as a powerful molecular typing method for outbreak analysis enabling the rapid discrimination between outbreak and non-outbreak isolates. However, such analysis can be challenging in the absence of closely related reference genomes. In this study, we assessed the use of WGS in investigating an outbreak of a relatively understudied bacterial pathogen with no publicly available closely related reference genome. Eleven Burkholderia cepacia complex (Bcc) isolates (seven from patients and four from disposable dermal gloves packages) that were collected during an outbreak were sequenced using the Illumina MiSeq platform. Our results showed that mapping the 11 sequenced Bcc outbreak isolates against a genetically distant reference genome yield loses coverage (31.6-48.3%) and a high number of detected false single-nucleotide polymorphisms (SNPs) (1123-2139). Therefore, a reference genome consensus from an outbreak clinical isolate was generated by combining both de novo assembly and mapping approaches. Based on this approach, we were able to demonstrate that the Bcc outbreak isolates were closely related and were phylogenetically distinct from the 11 publically available Bcc genomes. In addition, the pairwise SNP distance analysis detected only 1 to 6 SNPs differences among the outbreak isolates, confirming that contaminated disposable dermal gloves were the cause of the outbreak.

Ethylhexylglycerin Impairs Membrane Integrity and Enhances the Lethal Effect of Phenoxyethanol

Preservatives are added to cosmetics to protect the consumers from infections and prevent product spoilage. The concentration of preservatives should be kept as low as possible and this can be achieved by adding potentiating agents. The aim of the study was to investigate the mechanisms behind potentiation of the bactericidal effect of a commonly used preservative, 2-phenoxyethanol (PE), by the potentiating agent ethylhexylglycerin (EHG). Sub-lethal concentrations of EHG (0.075%) and PE (0.675%) in combination led to rapid killing of E. coli (> 5 log reduction of cfu after 30 min), leakage of cellular constituents, disruption of the energy metabolism, morphological deformities of cells and condensation of DNA. Used alone, EHG disrupted the membrane integrity even at low concentrations. In conclusion, sub-lethal concentrations of EHG potentiate the effect of PE through damage of the cell membrane integrity. Thus, adding EHG to PE in a 1:9 ratio has a similar effect on membrane damage and bacterial viability as doubling the concentration of PE. This study provides insight about the mechanism of action of a strong potentiating agent, EHG, which is commonly used in cosmetics together with PE.

Critical analysis of common canister programs: a review of cross-functional considerations and health system economics

Respiratory inhalers constitute a large percentage of hospital pharmacy expenditures. Metered-dose inhaler (MDI) canisters usually contain enough medication to last 2 to 4 weeks, while the average hospital stay for acute hospitalizations of respiratory illnesses is only 4-5 days. Hospital pharmacies are often unable to operationalize relabeling of inhalers at discharge to meet regulatory requirements. This dilemma produces drug wastage. The common canister (CC) approach is a method some hospitals implemented in an effort to minimize the costs associated with this issue. The CC program uses a shared inhaler, an individual one-way valve holding chamber, and a cleaning protocol. This approach has been the subject of considerable controversy. Proponents of the CC approach reported considerable cost savings to their institutions. Opponents of the CC approach are not convinced the benefits outweigh even a minimal risk of cross-contamination since adherence to protocols for hand washing and disinfection of the MDI device cannot be guaranteed to be 100% (pathogens from contaminated devices can enter the respiratory tract through inhalation). Other cost containment strategies, such as unit dose nebulizers, may be useful to realize similar reductions in pharmacy drug costs while minimizing the risks of nosocomial infections and their associated medical costs. The CC strategy may be appropriate for some hospital pharmacies that face budget constraints, but a full evaluation of the risks, benefits, and potential costs should guide those who make hospital policy decisions.

Healthcare-associated respiratory tract infection and colonization in an intensive care unit caused by Burkholderia cepacia isolated in mouthwash

OBJECTIVES

Burkholderia cepacia has been linked to healthcare-associated infections and colonization caused by contamination of alcohol-free mouthwash used in patients undergoing mechanical ventilation. The purpose of our study was to establish the source of a clustering of healthcare-associated B. cepacia isolates in patients on mechanical ventilation in the intensive care unit (ICU).

METHODS

During April 2012 the Infection Control Committee became concerned when B. cepacia was isolated from tracheal aspirate cultures of three ICU patients. The medical records for the years 2011 and 2012 were reviewed to identify further cases. Cultures of potential reservoirs were done. Isolates from patients and an alcohol-free mouthwash were submitted to multilocus sequence typing (MLST) analysis and antimicrobial resistance testing.

RESULTS

Four patients with positive cultures for B. cepacia were identified before the review of the medical records for the years 2011 and 2012. Nine further cases were identified in the review, defined as a patient with pneumonia who had a culture of respiratory secretions that was positive for B. cepacia. Three were cases of infection and 10 were colonizations. All of the isolates from patients (J, K, L, and M) and mouthwash samples (B19, B20, and B21) were genetically identical by MLST analysis.

CONCLUSIONS

Our findings strongly suggest that alcohol-free mouthwash solution intrinsically contaminated with B. cepacia was the source of these colonizations and infections involving adults in the ICU.

Insights into β-lactamases from Burkholderia species, two phylogenetically related yet distinct resistance determinants

Burkholderia cepacia complex and Burkholderia pseudomallei are opportunistic human pathogens. Resistance to β-lactams among Burkholderia spp. is attributable to expression of β-lactamases (e.g. PenA in B. cepacia complex and PenI in B. pseudomallei). Phylogenetic comparisons reveal that PenA and PenI are highly related. However, the analyses presented here reveal that PenA is an inhibitor-resistant carbapenemase, most similar to KPC-2 (the most clinically significant serine carbapenemase), whereas PenI is an extended spectrum β-lactamase. PenA hydrolyzes β-lactams with k(cat) values ranging from 0.38 ± 0.04 to 460 ± 46 s(-1) and possesses high k(cat)/k(inact) values of 2000, 1500, and 75 for β-lactamase inhibitors. PenI demonstrates the highest kcat value for cefotaxime of 9.0 ± 0.9 s(-1). Crystal structure determination of PenA and PenI reveals important differences that aid in understanding their contrasting phenotypes. Changes in the positioning of conserved catalytic residues (e.g. Lys-73, Ser-130, and Tyr-105) as well as altered anchoring and decreased occupancy of the deacylation water explain the lower k(cat) values of PenI. The crystal structure of PenA with imipenem docked into the active site suggests why this carbapenem is hydrolyzed and the important role of Arg-220, which was functionally confirmed by mutagenesis and biochemical characterization. Conversely, the conformation of Tyr-105 hindered docking of imipenem into the active site of PenI. The structural and biochemical analyses of PenA and PenI provide key insights into the hydrolytic mechanisms of β-lactamases, which can lead to the rational design of novel agents against these pathogens.