Outbreak of Burkholderia cepacia bacteremia traced to contaminated hospital water used for dilution of an alcohol skin antiseptic

An outbreak of Burkholderia cepacia bloodstream infections in a tertiary-care facility in northern India detected by a healthcare-associated infection surveillance network

OBJECTIVE

The burden of healthcare-associated infections (HAIs) is higher in low- and middle-income countries, but HAIs are often missed because surveillance is not conducted. Here, we describe the identification of and response to a cluster of Burkholderia cepacia complex (BCC) bloodstream infections (BSIs) associated with high mortality in a surgical ICU (SICU) that joined an HAI surveillance network.

SETTING

A 780-bed, tertiary-level, public teaching hospital in northern India.

METHODS

After detecting a cluster of BCC in the SICU, cases were identified by reviewing laboratory registers and automated identification and susceptibility testing outputs. Sociodemographic details, clinical records, and potential exposure histories were collected, and a self-appraisal of infection prevention and control (IPC) practices using assessment tools from the World Health Organization and the US Centers for Disease Control and Prevention was conducted. Training and feedback were provided to hospital staff. Environmental samples were collected from high-touch surfaces, intravenous medications, saline, and mouthwash.

RESULTS

Between October 2017 and October 2018, 183 BCC BSI cases were identified. Case records were available for 121 case patients. Of these 121 cases, 91 (75%) were male, the median age was 35 years, and 57 (47%) died. IPC scores were low in the areas of technical guidelines, human resources, and monitoring and evaluation. Of the 30 environmental samples, 4 grew BCC. A single source of the outbreak was not identified.

CONCLUSIONS

Implementing standardized HAI surveillance in a low-resource setting detected an ongoing Burkholderia cepacia outbreak. The outbreak investigation and use of a multimodal approach reduced incident cases and informed changes in IPC practices.

Cluster of Burkholderia cepacia Complex Infections Associated with Extracorporeal Membrane Oxygenation Water Heater Devices

BACKGROUND

Burkholderia cepacia complex is a group of potential nosocomial pathogens often linked to contaminated water. We report on a cluster of 8 B.cepacia complex infections in cardiothoracic ICU patients attributed to contaminated ECMO water heaters.

METHODS

In December 2020, we identified an increase in B.cepacia complex infections in the cardiothoracic ICU at Brigham and Women's Hospital. We sought commonalities, sequenced isolates, obtained environmental specimens, and enacted mitigation measures.

RESULTS

Whole genome sequencing of 13 B.cepacia complex clinical specimens between November 2020-February 2021 identified 6 clonally related isolates, speciated as Burkholderia contaminans. All 6 occurred in patients on ECMO. Microbiology review identified two additional B.contaminans cases from June 2020, including one ECMO patient, that may have been cluster-related as well. All 8 definite/probable cluster cases required treatment; 3 died and 3 developed recurrent infections. After ECMO was identified as the major commonality, all 9 of the hospital's ECMO water heaters were cultured; all grew B.contaminans. Air sampling adjacent to the water heaters was culture-negative. Water heater touch screens were culture-positive for B.contaminans. The sink drain in the ECMO heater reprocessing room also grew clonal B.contaminans. Observations of reprocessing revealed opportunities for cross-contamination between devices via splash from the contaminated sink. The cluster was aborted by removing all water heaters from clinical service.

CONCLUSIONS

We identified a cluster of 8 B.cepacia complex infections associated with contaminated ECMO water heaters. This cluster underscores the potential risks associated with water-based ECMO heaters and, more broadly, water-based care for vulnerable patients.

Clinical and Microbiological Profile of Patients with Bloodstream Infections Caused by Burkholderia cepacia Complex

Introduction Burkholderia cepacia complex (BCC) is an emerging pathogen causing nosocomial bloodstream infections (BSIs), and its treatment is challenging due to its multidrug resistance. In India, there is a dearth of data on BSIs caused by BCC, therefore, an updated study is required to know the clinical and microbiological profile of these patients. We aimed to study the clinical epidemiology and antibiotic susceptibility pattern of BCC isolated from blood samples in our hospital.

Materials and Methods This observational study was conducted from January 2019 to December 2020 at a tertiary care center in northern India. All the blood cultures were done on an automated blood culture system. All BCC isolates of BSI were identified depending on their morphological properties and biochemical reactions, and underwent the matrix-assisted laser desorption ionization time-of-flight mass spectrometry system to confirm diagnosis. Antibiotic susceptibility testing was done as per Clinical Laboratory and Standards Institute guidelines.

Results BCC was isolated from 30 BSI patients over a 2-year period. Sixty-six percent (20/30) of patients had cancer and a majority of them were undergoing chemotherapy. The most common predisposing factors were the use of steroids, immunosuppressive drugs, and chemotherapy (93.3%), central lines (83.3%), use of higher antibiotics (60%), and diabetes mellitus type 2 (60%). The most common species isolated were B. cepacia (64%) and B. cenocepacia (30%). Isolates showed highest sensitivity to minocycline (100%), ceftazidime (73.3%), and meropenem (70%) and the least to ticarcillin–clavulanate.

Conclusion BCC is an emerging pathogen causing BSIs, especially in malignancy patients. Minocycline can be a good choice for these bacteria.

Unusual Penile Prolapse with an Infectious Background Caused by the Burkholderia cepacia Complex in a Stallion

Penile prolapse is a disease manifested by an inability to retract the penis into the preputial sheath. It is reported in a variety of animal species, especially in young and intact males. However, penile prolapse in horses is commonly caused by trauma, sexual activity, pseudohermaphroditism, or neurological deficits, and less often by an infectious background. The present case report aimed to determine the etiological factor of penis infection associated with penile prolapse in a stallion in Poland. Our report indicates that the infectious background of penile prolapse was related to the Burkholderia cepacia complex. Based on antibiotic susceptibility results, the stallion was administered effective streptomycin and enrofloxacin treatment and recovered without complications. The following options are likely to be the infection source: contamination of hay or animal hygiene products. Finally, given its ability to grow in antiseptic solutions, difficulties in culturing, and innate multidrug resistance, this microorganism is currently a challenge to both detection and treatment in veterinary medicine cases.

Management and outcomes of Burkholderia cepacia complex bacteremia in patients without cystic fibrosis: a retrospective observational study

Burkholderia cepacia complex (BCC) is an emerging pathogen of nosocomial infection in chronic or critically ill patients without cystic fibrosis (CF). The objective was to evaluate the management and outcomes of BCC bacteremia in patients without CF. We conducted a retrospective study of non-CF adult patients with BCC bacteremia between January 1997 and December 2016 at 4 tertiary hospitals in South Korea. A total of 216 non-CF patients with BCC bacteremia were identified. Most cases were hospital-acquired (79.2%), and the most common source was a central venous catheter (CVC) (42.1%). The rates of susceptibility to trimethoprim-sulfamethoxazole and piperacillin-tazobactam of BCC isolates were high as 92.8% and 90.3%, respectively. The rates of susceptibility to ceftazidime, meropenem, and levofloxacin were 75.5%, 72.3%, and 64.1%, respectively. The 14-day, 30-day, and in-hospital mortality rate was 19.4%, 23.1%, and 31.0%, respectively. Female (OR = 3.1; 95% CI, 1.4-6.8), liver cirrhosis (OR = 6.2; 95% CI, 1.6-16.6), septic shock (OR = 11.2; 95% CI, 5.1-24.8), and catheter-related infection (OR = 2.6, 95% CI, 1.2-5.8) were the independent risk factors for 30-day mortality. The outcome did not differ according to type of antibiotics used. Among 91 patients with CVC-related BCC bacteremia, delayed CVC removal (> 3 days) had a higher rate of persistent bacteremia (54.5 vs. 26.1%; P = 0.03) and lower rate of clinical response (49.0 vs. 71.9%; P = 0.04), compared with early CVC removal (within 3 days). BCC bacteremia occurring in non-CF patients was mostly hospital-acquired and CVC-related. Early removal of the catheter is crucial in treatment of CVC-related BCC bacteremia.

Temporal variations in bacterial community diversity and composition throughout intensive care unit renovations

BACKGROUND

Inanimate surfaces within a hospital serve as a reservoir of microbial life that may colonize patients and ultimately result in healthcare associated infections (HAIs). Critically ill patients in intensive care units (ICUs) are particularly vulnerable to HAIs. Little is known about how the microbiome of the ICU is established or what factors influence its evolution over time. A unique opportunity to bridge the knowledge gap into how the ICU microbiome evolves emerged in our health system, where we were able to characterize microbial communities in an established hospital ICU prior to closing for renovations, during renovations, and then after re-opening.

RESULTS

We collected swab specimens from ICU bedrails, computer keyboards, and sinks longitudinally at each renovation stage, and analyzed the bacterial compositions on these surfaces by 16S rRNA gene sequencing. Specimens collected before ICU closure had the greatest alpha diversity, while specimens collected after the ICU had been closed for over 300 days had the least. We sampled the ICU during the 45 days after re-opening; however, within that time frame, the alpha diversity never reached pre-closure levels. There were clear and significant differences in microbiota compositions at each renovation stage, which was driven by environmental bacteria after closure and human-associated bacteria after re-opening and before closure.

CONCLUSIONS

Overall, we identified significant differences in microbiota diversity and community composition at each renovation stage. These data help to decipher the evolution of the microbiome in the most critical part of the hospital and demonstrate the significant impacts that microbiota from patients and staff have on the evolution of ICU surfaces. Video Abstract.

Niche specialization and spread of Staphylococcus capitis involved in neonatal sepsis

The multidrug-resistant Staphylococcus capitis NRCS-A clone is responsible for sepsis in preterm infants in neonatal intensive care units (NICUs) worldwide. Here, to retrace the spread of this clone and to identify drivers of its specific success, we investigated a representative collection of 250 S. capitis isolates from adults and newborns. Bayesian analyses confirmed the spread of the NRCS-A clone and enabled us to date its emergence in the late 1960s and its expansion during the 1980s, coinciding with the establishment of NICUs and the increasing use of vancomycin in these units, respectively. This dynamic was accompanied by the acquisition of mutations in antimicrobial resistance- and bacteriocin-encoding genes. Furthermore, combined statistical tools and a genome-wide association study convergently point to vancomycin resistance as a major driver of NRCS-A success. We also identified another S. capitis subclade (alpha clade) that emerged independently, showing parallel evolution towards NICU specialization and non-susceptibility to vancomycin, indicating convergent evolution in NICU-associated pathogens. These findings illustrate how the broad use of antibiotics can repeatedly lead initially commensal drug-susceptible bacteria to evolve into multidrug-resistant clones that are able to successfully spread worldwide and become pathogenic for highly vulnerable patients.

Betaproteobacteria are predominant in drinking water: are there reasons for concern?

Betaproteobacteria include some of the most abundant and ubiquitous bacterial genera that can be found in drinking water, including mineral water. The combination of physiology and ecology traits place some Betaproteobacteria in the list of potential, yet sometimes neglected, opportunistic pathogens that can be transmitted by water or aqueous solutions. Indeed, some drinking water Betaproteobacteria with intrinsic and sometimes acquired antibiotic resistance, harbouring virulence factors and often found in biofilm structures, can persist after water disinfection and reach the consumer. This literature review summarises and discusses the current knowledge about the occurrence and implications of Betaproteobacteria in drinking water. Although the sparse knowledge on the ecology and physiology of Betaproteobacteria thriving in tap or bottled natural mineral/spring drinking water (DW) is an evidence of this review, it is demonstrated that DW holds a high diversity of Betaproteobacteria, whose presence may not be innocuous. Frequently belonging to genera also found in humans, DW Betaproteobacteria are ubiquitous in different habitats, have the potential to resist antibiotics either due to intrinsic or acquired mechanisms, and hold different virulence factors. The combination of these factors places DW Betaproteobacteria in the list of candidates of emerging opportunistic pathogens. Improved bacterial identification of clinical isolates associated with opportunistic infections and additional genomic and physiological studies may contribute to elucidate the potential impact of these bacteria.

Emergence of Burkholderia cepacia in ICU Setting

BACKGROUND

B. cepacia is metabolically versatile organism which is not only resistant to many antibiotics but also disinfectants. This makes their survival easy even in restricted areas like intensive care unit (ICU) and management difficult.

AIMS AND OBJECTIVES

To describe sudden emergence of Burkholderia at a tertiary care centre ICU setting in milieu of colistin usage.

MATERIALS AND METHODS

Cases were patients with culture proven B.cepacia. They were picked up as non-lactose fermenting, oxidase positive, motile, gram-negative bacilli which was resistant to colistin and aminoglycosides and sensitive to cotrimoxazole. These isolates were further confirmed by both VITEK-2 compact system (Biomerieux, France) and standard bacterial techniques.Colistin consumption data were retrospectively collected from medical store records of hospitals and individual ICU pharmacy records from January 2016 to June 2016, and were expressed as total dialy doses in a month per 1000 patient days (DDD/1000PD).

RESULTS

An increase was observed in B. cepacia infection linked to increased consumption of colistin in ICU.

CONCLUSION

Based on these results an increase was observed in B.cepacia infection which correlated with increased consumption of colistin in ICU. We speculate that extensive use of colistin may lead to selection of intrinsically resistant B. cepacia and may facilitate their spread as nosocomial pathogens.

HOW TO CITE THIS ARTICLE

Meena S, Bir R, Sood S, Das BK, Kapil A. Emergence of Burkholderia cepacia in ICU Setting. Indian J Crit Care Med 2019;23(9):423-426.

Burkholderia cepacia meningitis in the Central African Republic

Burkholderia cepacia causes frequent infections in immunocompromised and hospitalized patients, with a significant mortality rate. This bacterial species has also been associated with epidemic outbreaks due to contamination of antiseptic solutions and parenteral and nebulized medications. In 2016, in the town of Bongonon in the north of the Central African Republic (CAR), a three-year-old boy with febrile meningeal syndrome (fever, neck stiffness and altered general condition) was admitted for a medical consultation provided by the nongovernmental organization MSF-Spain. On 20 March 2016, a sample of the boy's cerebrospinal fluid was sent to the Bacteriology Laboratory of the Pasteur Institute of Bangui for analysis. Conventional bacteriology showed that the isolate was a Gram-negative bacillus, which was identified as B. cepacia by using API 20 NE, with 99.9%confidence. In addition, the strain presented an acquired resistance to ticarcillin-clavulanate, ceftazidime and imipenem but remained susceptible to cotrimoxazole. As B. cepacia had never previously been isolated from cerebrospinal fluid in Africa, we chose to identify the strain by 16S rRNA gene sequencing. The molecular data showed that the isolate belonged to B. cepacia group. This is the first report of a case of meningitis caused by B. cepacia in CAR and developing countries.

Cellulitis caused by the Burkholderia cepacia complex associated with contaminated chlorhexidine 2% scrub in five domestic cats

Isolates of the Burkholderia cepacia complex (BCC) are known as plant and human pathogens. We describe herein BCC infections as the cause of subcutaneous abscesses and purulent cellulitis in 5 cats. All cats were presented with an open wound, and 4 received standard wound care and empiric antibiotic therapy. Despite treatment, clinical signs worsened in 4 cats. Isolates of the BCC were obtained from all 5 cases. Two cats were submitted for postmortem examination. Subcutaneous abscesses with draining fistulas were observed. Histopathology revealed severe, pyogranulomatous cellulitis with intralesional gram-negative bacilli. Based on susceptibility results, the other 3 cats were administered effective antibiotics and recovered without complications. The BCC was cultured from the 2% chlorhexidine surgical scrub solution used in the clinic, suggesting the source of infection for 4 of 5 cats. Given the ability to grow in antiseptic solutions, the extra steps required to culture from antiseptics, and innate multidrug resistance, the BCC poses a challenge to both detect and treat. Although the BCC causes disease almost exclusively in humans with cystic fibrosis or immunodeficiency, the bacteria should also be a differential for nosocomial infections in veterinary patients.

Genomic and Transcriptomic Insights into How Bacteria Withstand High Concentrations of Benzalkonium Chloride Biocides

Benzalkonium chlorides (BAC) are commonly used biocides in broad-spectrum disinfectant solutions. How microorganisms cope with BAC exposure remains poorly understood, despite its importance for disinfection and disinfectant-induced antibiotic resistance. To provide insights into these issues, we exposed two isolates of an opportunistic pathogen, Pseudomonas aeruginosa, to increasing concentrations of BAC. One isolate was preadapted to BAC, as it originated from a bioreactor fed with subinhibitory concentrations of BAC for 3 years, while the other originated from a bioreactor that received no BAC. Replicated populations of both isolates were able to survive high concentrations of BAC, up to 1,200 and 1,600 mg/liter for the non- and preadapted strains, respectively, exceeding typical application doses. Transcriptome sequencing (RNA-seq) analysis revealed upregulation of efflux pump genes and decreased expression of porins related to BAC transport as well as reduced growth rate. Increased expression of spermidine (a polycation) synthase genes and mutations in the pmrB (polymyxin resistance) gene, which cause a reduction in membrane negative charge, suggested that a major adaptation to exposure to the cationic surfactant BAC was to actively stabilize cell surface charge. Collectively, these results revealed that P. aeruginosa adapts to BAC exposure by a combination of mechanisms and provided genetic markers to monitor BAC-resistant organisms that may have applications in the practice of disinfection.IMPORTANCE BAC are widely used as biocides in disinfectant solutions, food-processing lines, domestic households, and health care facilities. Due to their wide use and mode of action, there has been rising concern that BAC may promote antibiotic resistance. Consistent with this idea, at least 40 outbreaks have been attributed to infection by disinfectant- and antibiotic-resistant pathogens such as P. aeruginosa However, the underlying molecular mechanisms that bacteria use to deal with BAC exposure remain poorly elucidated. Elucidating these mechanisms may be important for monitoring and limiting the spread of disinfectant-resistant pathogens. Using an integrated approach that combined genomics and transcriptomics with physiological characterization of BAC-adapted isolates, this study provided a comprehensive understanding of the BAC resistance mechanisms in P. aeruginosa Our findings also revealed potential genetic markers to detect and monitor the abundance of BAC-resistant pathogens across clinical or environmental settings. This work contributes new knowledge about high concentrations of benzalkonium chlorides disinfectants-resistance mechanisms at the whole-cell genomic and transcriptomic level.

Burkholderia multivorans: A rare yet emerging cause of bacterial meningitis

Burkholderia multivorans is a member of the Burkholderia cepacia complex. Although it is usually associated with infections in patients with cystic fibrosis, chronic granulomatous disease, and immunosuppression, central nervous infections are not commonly reported. Moreover, management of these infections is difficult due to multiple mechanisms of bacterial resistance to antimicrobial agents. We report a 55-year-old-man who developed Burkholderia multivorans meningitis after two episodes of central line-associated bloodstream infections. The patient was successfully treated with intravenous trimethoprim/sulfamethoxazole. Burkholderia multivorans is an emerging cause of meningitis with limited antibacterial treatment options. However, trimethoprim/sulfamethoxazole remains an effective agent with excellent penetration into the central nervous system. To our knowledge, this is the first case reported of Burkholderia cepacia complex meningitis identified to the species level as Burkholderia multivorans.

Suspicious outbreak of ventilator-associated pneumonia caused by Burkholderia cepacia in a surgical intensive care unit

BACKGROUND

We reviewed Burkholderia cepacia infections in a hospital from 2013-2016 to report a suspicious outbreak that occurred in a surgical intensive care unit in 2015, and to outline the infection control measures adopted thereafter.

METHODS

Review of the health care-associated infection data regarding B cepacia via the surveillance system, hospital information system, electronic medical records, and laboratory information system together with the outbreak investigation was managed by the health care-associated infection control team.

RESULTS

During June 1-14, 2015, 4 cases of ventilator-associated pneumonia (VAP) were identified; B cepacia was isolated from endotracheal aspirate samples. On June 16, 120 environmental samples were collected and analyzed for microbiologic differentiation. Thirteen strains of B cepacia were prominently found in the expiratory blocks of ventilators, revealing the biocontamination source. After chemical disinfection without damaging ventilator components, repeat microbiologic testing of random ventilator samples yielded negative results until July 30, 2015. Retrospective data showed that isolation rates of B cepacia strains had increased since 2014. Although the resistance phenotype of these strains varied slightly, they exhibited similar patterns of antibiotic susceptibility.

CONCLUSIONS

Routine cleaning and disinfection of ventilators, in addition to an intervention bundle, should form part of an integrated VAP prevention and management approach.

Burkholderia contaminans Colonization from Contaminated Liquid Docusate (Colace) in a Immunocompetent Adult with Legionnaire's Disease: Infection Control Implications and the Potential Role of Candida pellucosa

Objective:B. contaminans was cultured from respiratory secretions and liquid docusate (Colace) in a Neurosurgical Intensive Care Unit (NICU) patient with community-acquired Legionnaire’s disease but not from another bottle given to the patient. Unexpectedly, C. pelliculosa was cultured from two bottles, but not the B. contaminans bottle or respiratory secretions. Methods:B. cepacia, later identified as B. contaminans, was cultured from a bottle of liquid docusate (Colace) dispensed to a non-cystic fibrosis patient. His respiratory secretions were colonized with B. contaminans. Results: Eradication of B. contaminans colonization in the patient’s respiratory secretions was attempted. With levofloxacin, B. contaminans developed multidrug resistance (MDR). Subsequent TMP-SMX therapy did not result in further MDR. Nine other ICU patients were given docusate from the same lot, but there were no other B. contaminans isolates. Conclusion:B. contaminans colonization of respiratory secretion may be difficult to eliminate. The significance of C. pelliculosa cultured from liquid docusate (Colace) remains to be elucidated. In this case, it appeared that B. contaminans may have inhibited the growth of C. pelliculosa in the same bottle. Others should be alerted to the possibility that C. pelliculosa may be present in B. contaminans–contaminated lots of liquid docusate (Colace).

Intrinsic Resistance of Burkholderia cepacia Complex to Benzalkonium Chloride

Pharmaceutical products that are contaminated with Burkholderia cepacia complex (BCC) bacteria may pose serious consequences to vulnerable patients. Benzyldimethylalkylammonium chloride (BZK) cationic surfactants are extensively used in medical applications and have been implicated in the coselection of antimicrobial resistance. The ability of BCC to degrade BZK, tetradecyldimethylbenzylammonium chloride (C14BDMA-Cl), dodecyldimethylbenzylammonium chloride (C12BDMA-Cl), decyldimethylbenzylammonium chloride (C10BDMA-Cl), hexyldimethylbenzylammonium chloride, and benzyltrimethylammonium chloride was determined by incubation in 1/10-diluted tryptic soy broth (TSB) to determine if BCC bacteria have the ability to survive and inactivate these disinfectants. With BZK, C14BDMA-Cl, and C12BDMA-Cl, inhibition of the growth of 20 BCC strains was observed in disinfectant solutions that ranged from 64 to 256 µg/ml. The efflux pump inhibitor carbonyl cyanide m-chlorophenylhydrazone increased the sensitivity of bacteria to 64 µg/ml BZK. The 20 BCC strains grew well in 1/10-diluted TSB medium with BZK, C12BDMA-Cl, and C10BDMA-Cl; they absorbed and degraded the compounds in 7 days. Formation of benzyldimethylamine and benzylmethylamine as the initial metabolites suggested that the cleavage of the C alkyl-N bond occurred as the first step of BZK degradation by BCC bacteria. Proteomic data confirmed the observed efflux activity and metabolic inactivation via biodegradation in terms of BZK resistance of BCC bacteria, which suggests that the two main resistance mechanisms are intrinsic and widespread.

IMPORTANCE

Benzyldimethylalkylammonium chloride is commonly used as an antiseptic in the United States. Several recent microbial outbreaks were linked to antiseptics that were found to contain strains of the Burkholderia cepacia complex. Burkholderia species survived in antiseptics, possibly because of the degradation of antiseptic molecules or regulation of relevant gene expression. In this study, we assessed the efflux pump and the potential of B. cepacia complex bacteria to degrade benzyldimethylalkylammonium chloride and improved our understanding of the resistance mechanisms, by using proteomic and metabolic information. To our knowledge, this is the first systematic report of the intrinsic mechanisms of B. cepacia complex strain resistance to benzyldimethylalkylammonium chloride, based on the metabolic and proteomic evidence for efflux pumps and the complete biodegradation of benzyldimethylalkylammonium chloride.

Candidate Essential Genes in Burkholderia cenocepacia J2315 Identified by Genome-Wide TraDIS

Burkholderia cenocepacia infection often leads to fatal cepacia syndrome in cystic fibrosis patients. However, antibiotic therapy rarely results in complete eradication of the pathogen due to its intrinsic resistance to many clinically available antibiotics. Recent attention has turned to the identification of essential genes as the proteins encoded by these genes may serve as potential targets for development of novel antimicrobials. In this study, we utilized TraDIS (Transposon Directed Insertion-site Sequencing) as a genome-wide screening tool to facilitate the identification of B. cenocepacia genes essential for its growth and viability. A transposon mutant pool consisting of approximately 500,000 mutants was successfully constructed, with more than 400,000 unique transposon insertion sites identified by computational analysis of TraDIS datasets. The saturated library allowed for the identification of 383 genes that were predicted to be essential in B. cenocepacia. We extended the application of TraDIS to identify conditionally essential genes required for in vitro growth and revealed an additional repertoire of 439 genes to be crucial for B. cenocepacia growth under nutrient-depleted conditions. The library of B. cenocepacia mutants can subsequently be subjected to various biologically related conditions to facilitate the discovery of genes involved in niche adaptation as well as pathogenicity and virulence.

Report on the newly emerging nosocomial Burkholderia cepacia in a tertiary hospital

BACKGROUND

Burkholderia cepacia is an aerobic, motile, opportunistic Gram negative bacillus that can survive in certain disinfectants. This is a report of the emerging infection with the bacteria B. cepacia in our hospital. The awareness of this emerging bacterium is important, as it is known to cause nosocomial infection in hospitals, especially in the Intensive Care Unit (ICU) setting. setting. B. cepacia, although known to be multidrug resistant, shows sensitivity to some antibiotics that can be used to treat infection caused by it.

METHODS

The cases of infection and antimicrobial susceptibility of nosocomial B. cepacia pattern have been analyzed.

RESULTS

A total of 38 cases with B. cepacia infection were isolated. Two of these cases showed the organism in two samples, totalling the sample collection to 40. The most frequent isolation of B. cepacia was from blood 21/40 (52.5%) and pus 9/40 (22.5%). B. cepacia infections were most commonly observed in the Intensive Care Unit (52.6%). Infections were more common in men than women with a mortality rate of 42%. The most sensitive antimicrobial agents were found to be Colistin (93%) and Cotrimoxazole (71%).

CONCLUSION

There have been 38 cases of the emerging nosocomial B. cepacia infection in our hospital in the period from September 2012 to February 2014. There was no case reported in the records before September 2012. Infections caused by B. cepacia should be made aware of and taken seriously because of its high transmissibility, intrinsic resistance to antibiotics, high mortality and most importantly its sensitivity to simple antibiotics such as Cotrimoxazole.

Infection Prevention and Control Guideline for Cystic Fibrosis: 2013 Update

The 2013 Infection Prevention and Control (IP&C) Guideline for Cystic Fibrosis (CF) was commissioned by the CF Foundation as an update of the 2003 Infection Control Guideline for CF. During the past decade, new knowledge and new challenges provided the following rationale to develop updated IP&C strategies for this unique population:

1.The need to integrate relevant recommendations from evidence-based guidelines published since 2003 into IP&C practices for CF. These included guidelines from the Centers for Disease Control and Prevention (CDC)/Healthcare Infection Control Practices Advisory Committee (HICPAC), the World Health Organization (WHO), and key professional societies, including the Infectious Diseases Society of America (IDSA) and the Society for Healthcare Epidemiology of America (SHEA). During the past decade, new evidence has led to a renewed emphasis on source containment of potential pathogens and the role played by the contaminated healthcare environment in the transmission of infectious agents. Furthermore, an increased understanding of the importance of the application of implementation science, monitoring adherence, and feedback principles has been shown to increase the effectiveness of IP&C guideline recommendations.

2.Experience with emerging pathogens in the non-CF population has expanded our understanding of droplet transmission of respiratory pathogens and can inform IP&C strategies for CF. These pathogens include severe acute respiratory syndrome coronavirus and the 2009 influenza A H1N1. Lessons learned about preventing transmission of methicillin-resistantStaphylococcus aureus(MRSA) and multidrug-resistant gram-negative pathogens in non-CF patient populations also can inform IP&C strategies for CF.

Efficient management and maintenance of ultrasonic nebulizers to prevent microbial contamination

AIM: To seek the cause of Burkholderia cepacia complex (Bcc) infection outbreak and evaluate the efficacy of new methods for nebulizer maintenance.

METHODS: We investigated the annual number of Bcc isolates recovered from clinical samples in our hospital between 1999 and 2013. Swab samples were randomly collected for bacterial culture before patient use from 10 each of the two machine types in August 2001; these included 20 samples from each of the following: Drain tubes, operating water chambers, oscillators, and nebulizing chambers. In addition, 10 samples each of nebulizer solutions before and after use were cultured. For environmental investigation, 10 samples were collected from sinks in the nurse stations of the wards where patients positive for Bcc were hospitalized. Numbers of Bcc isolates were compared before and after introduction of new methods for nebulizer maintenance in October 2001. In addition, randomly amplified polymorphic DNA (RAPD) assay was applied to find the genetic divergence of the Bcc isolates obtained from clinical samples and nebulizers.

RESULTS: From January 1999 to December 2013, a total of 487 Bcc isolates were obtained from clinical specimens from 181 patients. Notably, 322 (66.1%) Bcc isolates were obtained from clinical specimens from 1999 to 2001, including 244 (115 patients) from sputum and 34 (11 patients) from blood. During this period, 14 isolates were obtained from nebulizer components. Among these, six were derived from nebulizer drain tubes, five from operating water chambers, and one from the oscillator before patient use, and two from nebulizer solutions after patient use. When Bcc was isolated from the nebulizer solution after patient use, Bcc was simultaneously detected in other parts of the nebulizer. Bcc was not isolated from any nebulizer solution before use. RAPD assays revealed similar DNA profiles in isolates obtained from patients and nebulizers. Investigation revealed damaged diaphragms in many nebulizers. The new maintenance methods for nebulizers, including restriction of the usage period, thorough disinfection, and routine check for diaphragm breakage, remarkably reduced Bcc isolation (165 isolates from patients in 12 years and 0 isolate from nebulizers in periodical sampling). In particular, Bcc has been isolated from blood from only one patient since the new methods were introduced.

CONCLUSION: Appropriate maintenance of ultrasonic nebulizers is crucial for preventing Bcc contamination of nebulizers and subsequent respiratory tract and blood infections.

Deep pyoderma caused by Burkholderia cepacia complex associated with ciclosporin administration in dogs: a case series

BACKGROUND

Bacteria of the Burkholderia cepacia complex (Bcc) are ubiquitous Gram-negative bacilli associated with fatal nosocomial infections in humans; multi-antibiotic resistance makes this organism a serious threat in hospital settings.

OBJECTIVE

To describe the historical, clinicopathological and treatment characteristics of Bcc-associated deep skin infections in dogs.

ANIMALS

Six dogs with skin infections in which skin bacterial cultures resulted in pure growth of Bcc.

METHODS

Retrospective study with review of medical records and skin biopsies.

RESULTS

All dogs were receiving oral ciclosporin at the time of skin infection development. All dogs were castrated males and four of six were West Highland white terriers. Cutaneous lesions consistent with deep pyoderma were confined mainly to the trunk. In all dogs skin cytology revealed a strong inflammatory response, with moderate to abundant numbers of intracellular (neutrophils and macrophages) and extracellular bacilli. In three dogs histopathology showed a multifocal, nodular to coalescing pyogranulomatous dermatitis associated with multifocal folliculitis and furunculosis. Tissue Giemsa and Gram stains identified numerous Gram-negative rods within macrophages. Antimicrobial susceptibility testing revealed multidrug-resistant Bcc strains with sensitivity to trimethoprim/sulfonamides in all dogs and to marbofloxacin, piperacillin and ceftazidime in three dogs. Successful treatment was achieved in all dogs using trimethoprim/sulfonamides or quinolones (marbofloxacin, ciprofloxacin) or doxycycline in conjunction with ciclosporin withdrawal.

CONCLUSIONS AND CLINICAL IMPORTANCE

Clinicians should be aware of the rare potential for Bcc-associated deep skin infections in dogs receiving oral ciclosporin. Owners should be made conscious of the potential transmission risk to humans or other animals.

An outbreak of Burkholderia cepacia complex pseudobacteremia associated with intrinsically contaminated commercial 0.5% chlorhexidine solution

BACKGROUND

Burkholderia cepacia complex (Bcc) is well-known for intrinsic resistance to certain antiseptics. We experienced a sudden rise in Bcc bloodstream infections in a 786-bed hospital. An investigation was conducted to identify the source and to intervene in the ongoing infections.

METHODS

The cases were defined as patients with positive blood cultures for Bcc from October 10, 2013-December 16, 2013. We reviewed medical records, interviewed health care workers, and audited the clinical laboratory. A microbiologic culture for a suspected antiseptic was performed, and interventions were instituted.

RESULTS

During the outbreak period, Bcc were isolated from 46 blood cultures from 40 patients. The temporal and spatial distributions did not reveal common factors. The clinical features of the case patients suggested pseudobacteremia. A 0.5% chlorhexidine solution product was found to be contaminated with Bcc and had been misused as a skin antiseptic during blood culture. After withdrawal of the product and staff education, the outbreak was terminated.

CONCLUSION

The pseudobacteremia was caused by contaminated 0.5% chlorhexidine from a single company. This contamination was permitted by multiple breaches of infection control principles that could have caused significant outbreaks of true infections. Regulatory actions at the government level are needed to ensure the sterility of antiseptics.

An outbreak of Burkholderia stabilis colonization in a nasal ward

OBJECTIVE

The aim of this study was to describe an outbreak of Burkholderia stabilis colonization among patients in a nasal ward.

METHODS

Multilocus sequence typing (MLST) was used for the molecular typing of B. stabilis isolates. Microbiological records were reviewed to delineate the colonization outbreak period. One hundred seventy-one cultures of environment and equipment samples from the nasal ward were performed to trace the source of contamination. Infection control measures were taken in order to end the outbreak.

RESULTS

All B. stabilis isolates were identified as a new MLST type, ST821. A total of 53 patients carried this B. stabilis in the nasal ward between March and September 2013, which was defined as the outbreak period. The source of the colonization was not determined because all environment cultures were negative for Burkholderia cepacia complex. No further B. stabilis carriers have been found in the ward since the implementation of interventions.

CONCLUSIONS

Attention must be paid to asymptomatic colonization in order to identify outbreaks early.

Investigation of an Outbreak of Central Venous Catheter–Associated Bloodstream Infection Due to Contaminated Water

An outbreak of central venous catheter-associated bloodstream infections was reported in a hospital in Ecuador. Commercially produced ampoules of water for injection were found to be contaminated withBurkholderia cepaciaandMyroides odoratus.Removal of these ampoules yielded a 10-fold reduction in the incidence of catheter-associated infection.

An Outbreak ofBurkholderia cepaciaComplex Associated with Intrinsically Contaminated Nasal Spray

Objective.

To determine the source ofBurkholderia cepaciacomplex associated with a hospital outbreak and describe the measures taken to identify and confirm the source.

Setting.

A 250-bed, tertiary care pediatric hospital in Denver, Colorado.

Methods.

An epidemiologic investigation was used to identify possible causes for an apparent outbreak ofB. cepaciacomplex in pediatric patients who had new positive cultures with this organism from December 2003 to February 2004. Chart review, microbiology reports, surgical records, site visits, literature review, staff interviews, and cultures of common products and equipment were performed to determine a source of contamination. Random amplified polymorphic DNA and pulsed-field gel electrophoresis typing, performed by 2 independent laboratories, were used for molecular typing of patient and source isolates.

Results.

Five pediatric patients had new positiveB. cepaciacomplex cultures from either the sinus or the respiratory tract, and all 5 patients had prior exposure to 0.05% oxymetazoline hydrochloride Major Twice-A-Day 12-hour nasal spray (Proforma, Miami, FL). Four of the 5 patients had isolates that were identical to theB. cepaciacomplex isolates recovered from the unopened Twice-A-Day 12-hour nasal spray.

Conclusions.

Intrinsic contamination of Major Twice-A-Day 12-hour nasal spray withB. cepaciacomplex resulted in nosocomial transmission to 4 patients at our facility and resulted in a voluntary product recall by the manufacturer.B. cepaciacomplex species are common contaminants of an increasing variety of nonsterile medical products. Enhanced culture techniques may be useful in evaluating possible product contamination, suggesting additional measures that should be considered to assure the safety of products that may be used in high-risk patients.

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.

Aetiology, source and prevention of waterborne healthcare-associated infections: a review

The purpose of this review is to discuss the scientific literature on waterborne healthcare-associated infections (HCAIs) published from 1990 to 2012. The review focuses on aquatic bacteria and describes both outbreaks and single cases in relation to patient characteristics, the settings and contaminated sources. An overview of diagnostic methods and environmental investigations is summarized in order to provide guidance for future case investigations. Lastly, on the basis of the prevention and control measures adopted, information and recommendations are given. A total of 125 reports were included, 41 describing hospitalized children. All cases were sustained by opportunistic pathogens, mainly Legionellaceae, Pseudomonadaceae and Burkholderiaceae. Hot-water distribution systems were the primary source of legionnaires’ disease, bottled water was mainly colonized by Pseudomonaceae, and Burkholderiaceae were the leading cause of distilled and sterile water contamination. The intensive care unit was the most frequently involved setting, but patient characteristics were the main risk factor, independent of the ward. As it is difficult to avoid water contamination by microbes and disinfection treatments may be insufficient to control the risk of infection, a proactive preventive plan should be put in place. Nursing staff should pay special attention to children and immunosuppressed patients in terms of tap-water exposure and also their personal hygiene, and should regularly use sterile water for rinsing/cleaning devices.

Clonally related Burkholderia contaminans among ventilated patients without cystic fibrosis

We investigated a cluster of 10 Burkholderia cepacia complex-positive cultures among ventilated patients and those with a tracheostomy in an acute care hospital. Isolates from 5 patients had outbreak-strain-related Burkholderia contaminans. Isolates of B. cepacia complex unrelated to the outbreak strain were cultured from a sink drain. The investigation identified practices that might have led to contamination of patient respiratory care supplies with tap water, which might have contributed to the cluster.

Multi-institutional outbreak of Burkholderia cepacia complex associated with contaminated mannitol solution prepared in compounding pharmacy

BACKGROUND

Burkholderia cepacia complex (BCC) has been described as a cause of nosocomial outbreaks. We describe an outbreak of and identify risk factors for nosocomial BCC infections associated with intrinsically contaminated mannitol 3% solution.

METHODS

Urinary and bloodstream infection caused by BCC were identified in hospitalized patients who underwent urologic surgery and received intraoperative irrigation of 3% mannitol solution in February 2009. The investigation included retrospective chart review, case control study, procedural review, and culture of mannitol solution.

RESULTS

Seven BCC infections were identified. BCC isolates were recovered from blood and/or urine from patients and lots of mannitol in use during the outbreak period. Mannitol solution was produced by a compounding pharmacy. Receipt of larger volumes of contaminated solution was identified as a significant risk factor for infection (odds ratio, 1.5; P value < .05). BCC was also cultured in lots of mannitol in use in other hospitals.

CONCLUSION

Manipulated mannitol solution is a potential source of infection. Contamination with paraben-degrading organisms can occur at the time of manufacture. Our findings suggest that contamination of mannitol at a compounding pharmacy occurred. Prompt communication to other hospitals and implementation of infection control measures were effective in avoiding further cases of infection.

An outbreak of Burkholderia cepacia bacteremia in hospitalized hematology patients selectively affecting those with acute myeloid leukemia

BACKGROUND

Burkholderia cepacia complex (Bcc) is a group of common environmental bacteria that preferentially colonize and infect patients with cystic fibrosis but are also emerging as nosocomial pathogens, possibly due to their resistance to disinfectants and antimicrobials.

METHODS

We investigated a 3-month outbreak of Bcc bacteremia among hospitalized hematology patients. Environmental investigation and infection control measures were implemented. A retrospective, cross-sectional study was conducted to identify risk factors.

RESULTS

Bcc was repeatedly isolated from the blood of 9 patients without central venous catheter who did not easily respond to targeted antibiotic treatment and 3 died of the infection. A point source was not identified and horizontal spread was suspected. Strict infection control measures terminated the outbreak. Interestingly, diagnosis of acute myeloid leukemia but not neutropenia or prior chemotherapy was a risk factor for infection acquisition. Neutropenia was positively correlated with infection duration.

CONCLUSIONS

Bcc is not only a serious threat among immunocompromized hematology patients, but is also transmissible in clinical settings. Acute myeloid leukemia appears to confer additional risk for infection acquisition.

Plumbing of hospital premises is a reservoir for opportunistically pathogenic microorganisms: a review

Several bacterial species that are natural inhabitants of potable water distribution system biofilms are opportunistic pathogens important to sensitive patients in healthcare facilities. Waterborne healthcare-associated infections (HAI) may occur during the many uses of potable water in the healthcare environment. Prevention of infection is made more challenging by lack of data on infection rate and gaps in understanding of the ecology, virulence, and infectious dose of these opportunistic pathogens. Some healthcare facilities have been successful in reducing infections by following current water safety guidelines. This review describes several infections, and remediation steps that have been implemented to reduce waterborne HAIs.

Risk factors for mortality in patients with Burkholderia cepacia complex bacteraemia

BACKGROUND

Over the last 2 decades, Burkholderia cepacia complex has emerged as a serious human pathogen, especially in critically ill patients. B. cepacia complex has been associated with increased morbidity and mortality in intensive care unit patients. However, in our literature search, we could not find studies on risk factors for mortality in patients with B. cepacia complex bacteraemia. Therefore, we investigated risk factors for mortality in B. cepacia complex bacteraemia.

METHODS

Clinical characteristics and laboratory parameters of 27 patients with 1 or more blood cultures positive for B. cepacia complex from January 2006 to October 2010 in Severance Hospital, Yonsei University College of Medicine, Korea were retrospectively analyzed. The main outcome measure was overall 28-day mortality. Appropriate initial empirical antimicrobial use was defined as administration of agent(s) to which the organism was susceptible within 24 h of obtaining blood for culture.

RESULTS

The overall 28-day mortality rate was 41% (11/27). In univariate analysis, underlying diabetes mellitus (p = 0.033), inappropriate initial empirical antimicrobial therapy (p = 0.033), and an elevated Sequential Organ Failure Assessment (SOFA) score (p = 0.002) were significantly associated with mortality. In multivariate analysis, inappropriate initial empirical antimicrobial therapy and an elevated SOFA score were independent risk factors for increased mortality (p = 0.032 and p = 0.028, respectively).

CONCLUSIONS

An elevated SOFA score and inappropriate initial empirical antimicrobial therapy were significantly associated with adverse outcome in patients with B. cepacia complex bacteraemia.

Molecular diagnostic analysis of outbreak scenarios

In the current laboratory assignment, technical aspects of the polymerase chain reaction (PCR) are integrated in the context of six different bacterial outbreak scenarios. The "Enterobacterial Repetitive Intergenic Consensus Sequence" (ERIC) PCR was used to analyze different outbreak scenarios. First, groups of 2-4 students determined optimal ERIC-PCR conditions to validate the protocol and subsequently applied ERIC-PCR to identify genetic relatedness among bacterial strains. Based on these genetic fingerprints, students selected the outbreak cases from the patient samples and assessed the risk factors for the outbreak scenario. Finally, students presented their findings during a classroom presentation. The results indicated that the assignment successfully facilitated student learning on the technical aspects of (ERIC) PCR and clearly demonstrated the practical application of PCR in a clinical diagnostic setting. Additionally, the assignment was highly appreciated by the students.

Outbreak of Burkholderia cepacia complex among ventilated pediatric patients linked to hospital sinks

We investigated a cluster of Burkholderia cepacia complex colonization in ventilated pediatric patients. Isolates from 15 patients, 2 sink drains, and several ventilator components were found to belong to a single B cenocepacia clone. Hospital tap water used during oral and tracheostomy care was identified as the most likely mechanism for transmission.

The changing microbial epidemiology in cystic fibrosis

Infection of the airways remains the primary cause of morbidity and mortality in persons with cystic fibrosis (CF). This review describes salient features of the epidemiologies of microbial species that are involved in respiratory tract infection in CF. The apparently expanding spectrum of species causing infection in CF and recent changes in the incidences and prevalences of infection due to specific bacterial, fungal, and viral species are described. The challenges inherent in tracking and interpreting rates of infection in this patient population are discussed.

Clinical practice guidelines for the diagnosis and management of intravascular catheter-related infection: 2009 Update by the Infectious Diseases Society of America

These updated guidelines replace the previous management guidelines published in 2001. The guidelines are intended for use by health care providers who care for patients who either have these infections or may be at risk for them.