A napkin-associated outbreak of Burkholderia cenocepacia bacteraemia in haemodialysis patients

Quaternary ammonium disinfectants and antiseptics: tolerance, resistance and potential impact on antibiotic resistance

BACKGROUND

Due to the substantial increase in the use of disinfectants containing quaternary ammonion compounds (QACs) in healthcare and community settings during the COVID-19 pandemic, there is increased concern that heavy use might cause bacteria to develop resistance to QACs or contribute to antibiotic resistance. The purpose of this review is to briefly discuss the mechanisms of QAC tolerance and resistance, laboratory-based evidence of tolerance and resistance, their occurrence in healthcare and other real-world settings, and the possible impact of QAC use on antibiotic resistance.

METHODS

A literature search was conducted using the PubMed database. The search was limited to English language articles dealing with tolerance or resistance to QACs present in disinfectants or antiseptics, and potential impact on antibiotic resistance. The review covered the period from 2000 to mid-Jan 2023.

RESULTS

Mechanisms of QAC tolerance or resistance include innate bacterial cell wall structure, changes in cell membrane structure and function, efflux pumps, biofilm formation, and QAC degradation. In vitro studies have helped elucidate how bacteria can develop tolerance or resistance to QACs and antibiotics. While relatively uncommon, multiple episodes of contaminated in-use disinfectants and antiseptics, which are often due to inappropriate use of products, have caused outbreaks of healthcare-associated infections. Several studies have identified a correlation between benzalkonium chloride (BAC) tolerance and clinically-defined antibiotic resistance. The occurrence of mobile genetic determinants carrying multiple genes that encode for QAC or antibiotic tolerance raises the concern that widespread QAC use might facilitate the emergence of antibiotic resistance. Despite some evidence from laboratory-based studies, there is insufficient evidence in real-world settings to conclude that frequent use of QAC disinfectants and antiseptics has promoted widespread emergence of antibiotic resistance.

CONCLUSIONS

Laboratory studies have identified multiple mechanisms by which bacteria can develop tolerance or resistance to QACs and antibiotics. De novo development of tolerance or resistance in real-world settings is uncommon. Increased attention to proper use of disinfectants is needed to prevent contamination of QAC disinfectants. Additional research is needed to answer many questions and concerns related to use of QAC disinfectants and their potential impact on antibiotic resistance.

In-use contamination of a hospital-grade disinfectant

BACKGROUND

Microbiological monitoring of disinfection of high-touch surfaces identified heavy growth of Serratia marcescens and Achromobacter xylosoxidans not present on surfaces before disinfection, suggesting contamination of the disinfectant used.

METHODS

An investigation included interview of the housekeeper involved, level of bacterial contamination of the in-use quaternary ammonium (Quat) disinfectant, bactericidal activity of the contaminated disinfectant, pulsed field gel electrophoresis of S.marcescens and Achromobacter isolates, survival of S. marcescens on dry surfaces, and genome sequencing to identify possible Quat resistance genes.

RESULTS

The housekeeper, who seldom cleaned patient rooms, had used the disinfectant for months without emptying and drying the bucket between uses. The contaminated disinfectant contained 9.3 × 10⁴ CFU of S. marcescens plus A. xylosoxidans. The log₁₀ reduction of S. marcescens by fresh Quat was 10²-fold lower than that achieved against a control strain (S. marcescens ATCC 13380). Genome sequencing of S. marcescens isolates identified the following genes previously shown to encode for efflux pumps associated with Quat resistance: sdeXY, sdeAB, smfY, and a sugE-like gene.

CONCLUSIONS

Failure to follow existing guidelines and manufacturer's instructions for use resulted in contamination by A. xylosoxidans and by S. marcescens that possessed multiple genes associated with Quat resistance.

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.

Distribution of Burkholderia cepacia complex species isolated from industrial processes and contaminated products in Argentina

Burkholderia cepacia complex (Bcc) members have clinical relevance as opportunistic pathogens in patients with cystic fibrosis and are responsible of numerous nosocomial infections. These closely related bacteria are also reported as frequent contaminants of industrial products. In this retrospective study, we use PCR and recA gene sequence analysis to identify at species level Bcc isolates recovered from massive consumption products and industrial processes in Argentina during the last 25 years. The sequences obtained were also compared with recA sequences from clinical Bcc isolates deposited in GenBank database. We detected Bcc in purified water and preserved products from pharmaceutics, cosmetics, household cleaning articles, and beverages industries. B. contaminans (which is prevalent among people with cystic fibrosis in Argentina) was the most frequent Bcc species identified (42% of the Bcc isolates studied). B. cepacia (10%), B. cenocepacia (5%), B. vietnamiensis (16%), B. arboris (3%), and the recently defined B. aenigmatica (24%) were also detected. Rec A sequences from all B. cepacia and most B. contaminans industrial isolates obtained in this study displayed 100% identity with recA sequences from isolates infecting Argentinean patients. This information brings evidence for considering industrial massive consumption products as a potential source of Bcc infections. In addition, identification at species level in industrial microbiological laboratories is necessary for a better epidemiological surveillance. Particularly in Argentina, more studies are required in order to reveal the role of these products in the acquisition of B. contaminans infections.

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.

Burkholderia Sepsis in Children as a Hospital-Acquired Infection

PURPOSE

Hospital-acquired Burkholderia cepacia (B. cepacia) infection are not commonly recorded in patients without underlying lung disease, such as cystic fibrosis and chronic granulomatous disease. However, in 2014, B. cepacia appeared more frequently in pediatric blood samples than in any other year. In order to access this situation, we analyzed the clinical characteristics of B. cepacia infections in pediatric patients at our hospital.

MATERIALS AND METHODS

We conducted a retrospective study of blood isolates of B. cepacia taken at our hospital between January 2004 and December 2014. Patient clinical data were obtained by retrospective review of electronic medical records. We constructed a dendrogram for B. cepacia isolates from two children and five adult patients.

RESULTS

A total of 14 pediatric patients and 69 adult patients were identified as having B. cepacia bacteremia. In 2014, higher rates of B. cepacia bacteremia were observed in children. Most of them required Intensive Care Unit (ICU) care (12/14). In eleven children, sputum cultures were examined, and five of these children had the same strain of B. cepacia that grew out from their blood samples. Antibiotics were administered based on antibiotic sensitivity results. Four children expired despite treatment. Compared to children, there were no demonstrative differences in adults, except for history of ICU care.

CONCLUSION

Although there were not many pediatric cases at our hospital, awareness of colonization through hospital-acquired infection and effective therapy for infection of B. cepacia is needed, as it can cause mortality and morbidity.

Polyclonal outbreak of bloodstream infections caused by Burkholderia cepacia complex in hematology and bone marrow transplant outpatient units

Aim: The objective was to describe an outbreak of bloodstream infections by Burkholderia cepacia complex (Bcc) in bone marrow transplant and hematology outpatients.

Methods: On February 15, 2008 a Bcc outbreak was suspected. 24 cases were identified. Demographic and clinical data were evaluated. Environment and healthcare workers' (HCW) hands were cultured. Species were determined and typed. Reinforcement of hand hygiene, central venous catheter (CVC) care, infusion therapy, and maintenance of laminar flow cabinet were undertaken. 16 different HCWs had cared for the CVCs. Multi-dose heparin and saline were prepared on counter common to both units.

Findings: 14 patients had B. multivorans (one patient had also B. cenopacia), six non-multivorans Bcc and one did not belong to Bcc. Clone A B. multivorans occurred in 12 patients (from Hematology); in 10 their CVC had been used on February 11/12. Environmental and HCW cultures were negative. All patients were treated with meropenem, and ceftazidime lock-therapy. Eight patients (30%) were hospitalized. No deaths occurred. After control measures (multidose vial for single patient; CVC lock with ceftazidime; cleaning of laminar flow cabinet; hand hygiene improvement; use of cabinet to store prepared medication), no new cases occurred.

Conclusions: This polyclonal outbreak may be explained by a common source containing multiple species of Bcc, maybe the laminar flow cabinet common to both units. There may have been contamination by B. multivorans (clone A) of multi-dose vials.

Hospital outbreak of Burkholderia stabilis bacteraemia related to contaminated chlorhexidine in haematological malignancy patients with indwelling catheters

Burkholderia cepacia complex (BCC) is an opportunistic pathogen that occasionally causes hospital outbreaks. This paper describes an outbreak of BCC bacteraemia in haematological malignancy patients related to a contaminated chlorhexidine gluconate solution. Eight BCC isolates were obtained from patients hospitalised in the same ward of a cancer centre in a Korean hospital. A further three BCC isolates were obtained from 0.5% chlorhexidine gluconate used in the same ward. The isolates were identified as B. stabilis and exhibited identical pulsed-field gel electrophoresis profiles. All patients with B. stabilis bacteraemia had indwelling intravenous catheters, which were treated with chlorhexidine to disinfect the catheters. Following identification of the source of contamination, strict controls regarding surveillance cultures for disinfectants have been enforced. No further B. stabilis infections have been found in the hospital.

Disinfection of Burkholderia cepacia complex from non-touch taps in a neonatal nursery

Burkholderia cepacia complex (Bcc) comprises nine closely related species or genomovars. It is an important causative agent of opportunistic infections and waterborne nosocomial infections. B. cepacia (formerly genomovar I) was identified from the blood culture of a baby in our neonatal unit (NU) in March 2005. B. cepacia was isolated four times from clinical specimens since the introduction of non-touch taps in the NU from 2000 to 2005 and only once from 1994 to 2000. Environmental samples were collected from the NU, including tap water from non-touch taps. Clinical and environmental isolates of Bcc were characterized using molecular identification and strain typing. A literature review was undertaken to delineate a method for eradication of Bcc. Several variations for hot water eradication of the organism from the taps were attempted. Genotyping and molecular analysis revealed that tap water isolates were B. cenocepacia which was a different species from the B. cepacia isolated from blood cultures of the neonate. However, B. cenocepacia has been known to cause nosocomial outbreaks and it was eventually eradicated from the NU by using repeated thermal shock (hot water at 65 degrees C for 10 min), changing taps and decolonizing sinks with hypochlorite. Molecular typing is useful in assisting the investigation of Bcc nosocomial infections.