Burkholderia cepacia Complex Bacteria: a Feared Contamination Risk in Water-Based Pharmaceutical Products

Draft genome of hydrocarbon-degrader Burkholderia cepacia BCTT, isolated from soil chronically polluted with crude oil in Trinidad

Burkholderia cepacia BCTT, isolated from chronically polluted soil in Trinidad, shows a capacity to survive in crude oil as a sole carbon source. Here, we report its high-quality draft genome sequence and highlight those pathways and genes involved in xenobiotic degradation. These data give a clearer insight into this organism's biotechnological potential.

Unraveling the Role of Contaminants Reshaping the Microflora in Zea mays Seeds from Heavy Metal-Contaminated and Pristine Environment

Heavy metal (HM) contaminants are the emerging driving force for reshaping the microflora of plants by eradicating the non-tolerance and non-resistant microbes via their lethal effects. Seeds served as a prime source of ancestral microbial diversity hereditary transfer from generation to generation. However, the problem arises when they got exposed to metal contamination, does metal pollutant disrupt the delicate balance of microbial communities within seeds and lead to shifts in their microflora across generations. In this study, the endophytic community within Zea mays seeds was compared across three distinct regions in Yunnan province, China: a HM-contaminated site Ayika (AK), less-contaminated site Sanduoduo (SD), and a non-contaminated Site Dali (DL). High-throughput sequencing techniques were employed to analyze the microbial communities. A total of 492,177 high-quality reads for bacterial communities and 1,001,229 optimized sequences for fungal communities were obtained. These sequences were assigned to 502 and 239 operational taxonomic units (OTUs) for bacteria and fungi, respectively. A higher diversity was recorded in AK samples than in SD and DL. Microbial community structure analysis showed higher diversity and significant fluctuation in specific taxa abundance in the metal-polluted samples exhibiting higher response of microbial flora to HM. In AK samples, bacterial genera such as Gordonia and Burkholderia-Caballeronia-Paraburkholderia were dominant, while in SD Pseudomonas and Streptomyces were dominant. Among the fungal taxa, Fusarium, Saccharomycopsis, and Lecanicillium were prevalent in HM-contaminated sites. Our finding revealed the influential effect of HM contaminants on reshaping the seed microbiome of the Zea mays, showing both the resilience of certain important microbial taxa as well the shifts in the diversity in the contaminated and pristine conditions. The knowledge will benefit to develop effective soil remediation, reclamation, and crop management techniques, and eventually assisting in the extenuation of metal pollution's adverse effects on plant health and agricultural productivity.

Burkholderia cepacia contaminating fresh frozen plasma causing transfusion transmitted bacterial infection

Bacterial contamination of plasma is unusual owing to frozen storage nevertheless reported. We report a case of transfusion transmitted infection due to Burkholderia cepacia contaminating fresh frozen plasma. A 31 year old male with decompensated chronic liver disease presented with breathlessness due to pleural effusion. Due to elevated prothrombin time, fresh frozen plasma was infused. After ten minutes of transfusion, he became febrile, tachypnoeic and transfusion was stopped. Plasma bag and blood cultures from patient grew B. cepacia. He became hemodynamically unstable due to underlying disease and died after a week.

A Burkholderia contaminans outbreak in an Intensive Care Unit associated with contaminated bath solution: control and microbiological findings

BACKGROUND

The Burkholderia cepacia complex (BCC) comprises a group of bacteria with a growing threat as a contaminant of non-sterile solutions. We describe an outbreak of a BCC involving patients at intensive care unit related to a no-rinse bathing solution (NRBS).

METHODS

We carried out patients, environmental and laboratory investigation performing analyses of cases, pulsed-field-gel electrophoresis and whole genome sequence (WGS) of isolates.

RESULTS

We investigated 32 cases and 16 isolates that were identified as Burkholderia contaminans, belonging to two different clones. One clone (new ST2175) was identified in 6 sequences (4 from patients; 2 from bath cart samples) and for the remaining 10 isolates (7 isolates from patients; 3 from NRBS) we identified the ST762. The investigation demonstrated that NRBS was the source of the outbreak caused by ST762 clone of B. contaminans.

DISCUSSION

Early suspicion of a common source, rapid implementation of control measures and laboratory support are vital in an outbreak investigation. We also highlight the role of WGS which was very important to conclude our investigation regarding environmental samples and bacterial typing.

CONCLUSION

We highlight the need to regulation water-based products and the role of WGS for investigate environmental samples.

Burkholderia multivorans Infections Associated with Use of Ice and Water from Ice Machines for Patient Care Activities - Four Hospitals, California and Colorado, 2020-2024

Ice machines can harbor water-related organisms, and the use of ice or tap water for clinical care activities has been associated with infections in health care settings. During 2021-2022, a total of 23 cases of infection by Burkholderia multivorans (sequence type ST659) were reported at two southern California hospitals and linked to contaminated ice and water from ice machines. In addition to these 23 cases, this report also includes 23 previously unreported cases of B. multivorans ST659 infections that occurred during 2020-2024: 13 at a northern California hospital, eight at a hospital in Colorado, and two additional cases at one of the southern California hospitals. The same brand of ice machine and brands of filters, descaling, and sanitizing products were used by all four hospitals; B. multivorans was isolated from samples collected from ice machines in two of the hospitals. Whole genome sequencing indicated that all clinical and ice machine isolates were highly genetically similar (0-14 single nucleotide variant differences across 81% of the selected reference genome). Recommendations from public health officials to halt the outbreak included avoiding ice and tap water during clinical care activities. An investigation is ongoing to determine possible sources of ice machine contamination. During outbreaks of water-related organisms in health care facilities, health care personnel should consider avoiding the use of tap water, including ice and water from ice machines, for patient care.

Choroid plexitis caused by Burkholderia cepacia complex after COVID-19

Burkholderia cepacia complex (BCC) encompasses opportunistic pathogen with various clinical manifestations ranging from no symptoms to severe respiratory infections and septicemia. Central nervous system infections caused by BCC are rare. To the best of our knowledge, we present the first reported case of choroid plexitis caused by BCC after severe COVID-19. A 67-year-old woman who had been previously diagnosed with COVID-19 presented with a mild fever and headache. Gadolinium-enhanced T1-weighted brain magnetic resonance imaging showed contrast effects in the right choroid plexus and encapsulated abscess. Gram staining of cerebrospinal fluid revealed the presence of gram-negative rods. Broad-range polymerase chain reaction amplification of 16S ribosomal RNA from the cerebrospinal fluid, followed by sequence analysis, identified BCC; thus, choroid plexitis caused by BCC was diagnosed. After prolonged antimicrobial treatment with a multiantibiotic regimen, the patient recovered completely. This case highlights the importance of long-term therapy with a carefully selected multiantibiotic regimen to achieve complete recovery after BCC infection.

A comprehensive review on biological funnel mechanism in lignin valorization: Pathways and enzyme dynamics

Lignin, a significant byproduct of the paper and pulp industry, is attracting interest due to its potential utilization in biomaterial-based sectors and biofuel production. Investigating biological methods for converting lignin into valuable products is crucial for effective utilization and has recently gained growing attention. Several microorganisms effectively decomposed low molecular weight lignins, transforming them into intermediate compounds via upper and lower metabolic pathways. This review focuses on assessing bacterial metabolic pathways involved in the breakdown of lignin into aromatic compounds and their subsequent utilization by different bacteria through various metabolic pathways. Understanding these pathways is essential for developing efficient synthetic metabolic systems to valorize lignin and obtain valuable industrial aromatic chemicals. The concept of "biological funneling," which involves examining key enzymes, their interactions, and the complex metabolic pathways associated with lignin conversion, is crucial in lignin valorization. By manipulating lignin metabolic pathways and utilizing biological routes, many aromatic compounds can be synthesized within cellular factories. Although there is insufficient evidence regarding the complete metabolism of polyaromatic hydrocarbons by particular microorganisms, understanding lignin-degrading enzymes, regulatory mechanisms, and interactions among various enzyme systems is essential for optimizing lignin valorization. This review highlights recent advancements in lignin valorization, bio-funneling, multi-omics, and analytical characterization approaches for aromatic utilization. It provides up-to-date information and insights into the latest research findings and technological innovations. The review offers valuable insights into the future potential of biological routes for lignin valorization.

Burkholderia cepacia cervical spondylodiscitis in a 39-year-old immunocompetent woman after a rhinoplasty: A case report and review of literature

Background

Burkholderia cepacia has been described as a rare etiology for spondylodiscitis (SD) after surgical procedures.

Case Description

We report a rare case of cervical SD caused by B. cepacia in a 39-year-old immunocompetent woman after a rhinoplasty treated with complex cervical surgery and prolonged antibiotic therapy. The follow-up visits showed no recurrence of symptoms.

Conclusion

Diagnostic and therapeutic of rare spinal infections, particularly those caused by atypical pathogens such as B. cepacia, are challenging. Identification and personalized therapy are crucial.

Efficacy of combination antibiotic therapy including inhaled tobramycin on Burkholderia cepacia pneumonia in a non-cystic fibrosis patient

Burkholderia cepacia complex (BCC) has been recognized as a serious cause of pneumonia in patients with cystic fibrosis. BCC infection has also been reported in non-cystic fibrosis patients. Notably, the mortality rate of bacterial pneumonia caused by BCC is high. Nonetheless, therapeutic management of BCC infection remains to be established. Recent reports have indicated successful treatment of BCC pneumonia with combination antibiotic therapy. However, no reports have detailed the efficacy of combination antibiotic therapy for both initial and recurrent BCC pneumonia management. We herein describe a rare case of BCC pneumonia in a non-cystic fibrosis patient that was successfully treated with a combination of intravenous, inhalational and oral antibiotics. Furthermore, antibiotic therapy including inhaled tobramycin has been continued after discharge from hospital, and no side effects or recurrence of bacterial pneumonia has been observed, although BCC has been detected in sputum. The findings of the present case suggest that combination antibiotic therapy including inhaled tobramycin may be effective for recurrent bacterial pneumonia caused by BCC. In the management of BCC infection, early diagnosis should be made based on sputum culture results, and combination antibiotic therapy should be initiated promptly.

Microbiological investigation of pregnancies following vaginal radical trachelectomy using 16S rRNA sequencing of FFPE placental specimens

This study examined the risk of intrauterine infection associated with radical trachelectomy (RT) in early-stage cervical cancer patients. This procedure preserves fertility but is linked to increased risk of intrauterine infection due to cervical defects during pregnancy. DNA was extracted from the formalin-fixed paraffin-embedded (FFPE) placental specimens of 23 pregnant post-RT patients and 16S rRNA gene sequencing was used for bacterial identification. The prevalence of Lactobacillus crispatus and Burkholderia stabilis was significantly higher in the non-chorioamnionitis group. In contrast, alpha diversity analysis using the PD index showed significantly higher diversity in the chorioamnionitis group (P = 0.04). The demonstrated relationship between chorioamnionitis and microbial diversity affirms the importance of controlling the genital bacterial flora in pregnancies following RT.

Mutation of hmgA, encoding homogentisate 1,2-dioxygenase, is responsible for pyomelanin production but does not impact the virulence of Burkholderia cenocepacia in a chronic granulomatous disease mouse lung infection

The Burkholderia cepacia complex (Bcc) is a group of Gram-negative opportunistic bacteria often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis (CF) and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals; pigment production has been reported to enable Bcc strains to overcome the host cell oxidative burst. In this work, we investigated the role of pyomelanin in resistance to oxidative stress and virulence in strains J2315 and K56-2, two epidemic CF isolates belonging to the Burkholderia cenocepacia ET-12 lineage. We previously reported that a single amino acid change from glycine to arginine at residue 378 in homogentisate 1,2-dioxygenase (HmgA) affects the pigment production phenotype: pigmented J2315 has an arginine at position 378, while non-pigmented K56-2 has a glycine at this position. Herein, we performed allelic exchange to generate isogenic non-pigmented and pigmented strains of J2315 and K56-2, respectively, and tested these to determine whether pyomelanin contributes to the protection against oxidative stress in vitro as well as in a respiratory infection in CGD mice in vivo. Our results indicate that the altered pigment phenotype does not significantly impact these strains' ability to resist oxidative stress with H2O2 and NO in vitro and did not change the virulence and infection outcome in CGD mice in vivo suggesting that other factors besides pyomelanin are contributing to the pathophysiology of these strains.IMPORTANCEThe Burkholderia cepacia complex (Bcc) is a group of Gram-negative opportunistic bacteria that are often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals and overcoming the host cell oxidative burst. We investigated the role of pyomelanin in Burkholderia cenocepacia strains J2315 (pigmented) and K56-2 (non-pigmented) and performed allelic exchange to generate isogenic non-pigmented and pigmented strains, respectively. Our results indicate that the altered pigment phenotype does not significantly impact these strains' ability to resist H2O2 or NO in vitro and did not alter the outcome of a respiratory infection in CGD mice in vivo. These results suggest that pyomelanin may not always constitute a virulence factor and suggest that other features are contributing to the pathophysiology of these strains.

Isolation of a PRD1-like phage uncovers the carriage of three putative conjugative plasmids in clinical Burkholderia contaminans

The Burkholderia cepacia complex (Bcc) is a group of increasingly multi-drug resistant opportunistic bacteria. This resistance is driven through a combination of intrinsic factors and the carriage of a broad range of conjugative plasmids harbouring virulence determinants. Therefore, novel treatments are required to treat and prevent further spread of these virulence determinants. In the search for phages infective for clinical Bcc isolates, CSP1 phage, a PRD1-like phage was isolated. CSP1 phage was found to require pilus machinery commonly encoded on conjugative plasmids to facilitate infection of Gram-negative bacteria genera including Escherichia and Pseudomonas. Whole genome sequencing and characterisation of one of the clinical Burkholderia isolates revealed it to be Burkholderia contaminans. B. contaminans 5080 was found to contain a genome of over 8 Mbp encoding multiple intrinsic resistance factors, such as efflux pump systems, but more interestingly, carried three novel plasmids encoding multiple putative virulence factors for increased host fitness, including antimicrobial resistance. Even though PRD1-like phages are broad host range, their use in novel antimicrobial treatments shouldn't be dismissed, as the dissemination potential of conjugative plasmids is extensive. Continued survey of clinical bacterial strains is also key to understanding the spread of antimicrobial resistance determinants and plasmid evolution.

Burkholderia cepacia in cystic fibrosis children and adolescents: overall survival and immune alterations

Background

In current literature there are only scarce data on the host inflammatory response during Burkholderia cepacia complex (Bcc) persistence. The primary objective of the present research was to carry out cross-sectional analyses of biomarkers and evaluate disease progression in cystic fibrosis (CF) patients with chronic Bcc infection and pathogen-free ones. The secondary aim was to assess prospectively overall survival of the study participants during up to 8 years of follow-up.

Methods

The study included 116 paediatric patients with CF; 47 CF patients were chronically infected with Bcc, and 69 individuals were Bcc free. Plasma and sputum biomarkers (neutrophil elastase, MMP-8, MMP-9, MMP-12, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IL-22, IL-23, IL-17, IFN-γ, TGFβ1, TNF-α) were analysed using commercially available kits. Besides, inhibitory effect of dexamethasone on proliferative response of PHA-stimulated peripheral blood lymphocytes had been assessed.

Results

Bcc infected patients did not differ from Bcc free ones in demographic and clinical parameters, but demonstrated an increased rate of glucose metabolism disturbances and survival disadvantage during prolong follow-up period. Biomarkers analyses revealed elevated TNF-α and reduced IL-17F levels in sputum samples of Bcc infected patients. These patients also demonstrated improvement of peripheral blood lymphocyte sensitivity to steroid treatment and reduction in plasma pro-inflammatory (IL-17F and IL-18) and anti-inflammatory (TGFβ1 and IL-10) cytokine concentrations.

Conclusions

Reduction in IL-17F levels may have several important consequences including increase in steroid sensitivity and glycemic control disturbances. Further investigations are needed to clarify the role of IL-17 cytokines in CF complication development. Low plasma TGFβ1 and IL-10 levels in Bcc infected group may be a sign of subverted activity of regulatory T cells. Such immune alterations may be one of the factors contributing to the development of the cepacia syndrome.

Outbreak of Burkholderia cenocepacia in an intensive care unit of a tertiary care hospital identified by pulsed-field gel electrophoresis

Nosocomial outbreaks of Burkholderia cepacia complex, transmitted through contaminated medical surfaces or equipment have been reported. Pulsed-field Gel Electrophoresis (PFGE) is recognized as the "gold standard" for molecular subtyping, yet studies on clonal relationships in India are limited. PFGE was used to study the clonal relationships of 22 isolates of Burkholderia cenocepacia from 12 patients admitted to a critical care unit during 2 months (November and December 2021). PFGE revealed three different profiles with 15 isolates belonging to a single cluster suggesting a common source within the hospital, emphasizing the need for preventive measures to control B. cenocepacia transmission.

Are Burkholderia Emerging Pathogens in patients with underlying morbidity: A case series

Burkholderia is a genus consisting of several species including the Burkholderia pseudomallei group, Burkholderia cepacia complex and other phytopathogens. Burkholderia species is a gram-negative bacillus with protean presentation that can be acquired from various sources, including water, soil, plant surfaces, and hospital environments. The organism on Gram staining is seen as gram-negative rod and on culture, the colonies are non-lactose fermenting. As it can mimic other diseases, it is frequently misdiagnosed and there is lack of awareness about the clinical spectrum of disease and diagnosis. This study aims to investigate varied clinical manifestations, identify potential risk factors and transmission modes and contribute to enhancing the clinical management of diseases. The increasing prevalence of Burkholderia infection implies its potential emergence as a significant public health concern, compounded by the growing incidence of diabetes, which has the potential to escalate the overall disease burden. The principal finding of the case series highlighted a spectrum of clinical presentations, emphasizing the need for comprehensive diagnostic strategies and tailored therapeutic interventions. These strategies will address the diverse manifestations and challenges posed by Burkholderia infections. This underscores the importance of heightened awareness among clinicians and microbiologists, given the need for extended treatment to achieve a complete cure and prevent potential relapses.

Epidemiology, microbiological, clinical characteristics, and outcome of Burkholderia cepacia complex infections in non-cystic fibrosis adult patients from Qatar

Objectives

Burkholderia species infections are associated with diverse and challenging clinical presentations because of distinct virulence and antimicrobial resistance factors. The study aims to evaluate the epidemiology, microbiological, and clinical outcomes of Burkholderia cepacia complex (Bcc) infections in non-cystic fibrosis (CF) patients from Qatar.

Methods

A retrospective study was conducted on adult patients across all hospitals at Hamad Medical Corporation between January 2012 and December 2018 to evaluate clinically relevant Bcc in non-CF adult patients.

Results

Over 7 years, 72 episodes of Burkholderia species infections were recorded, 64 were secondary to Bcc primarily affecting males (78.12%) with a mean age of 53 years, from the Middle and Southeastern region (92.2%) affected predominantly by diabetes mellitus (34.4%), chronic kidney (23.4%), coronary heart (20.3%), and hypertensive diseases (17.2%) while recent hospitalization and admission to critical care were evident in 45.3% and 93.8% of cases, respectively. Main infection sites were urinary (43.8%) and respiratory (29.7%) with associated bacteremia recorded in 26.6% of cases. Microbiological characteristics demonstrated high-level resistance profiles leading to delayed microbiological clearance in case of bacteremia (61%) and management with multiple therapeutic agents (range 4-6) resulting in disease resolution in 90.6% of cases with observed 30-day mortality of 7.8%.

Conclusions

B. cepacia infections are infrequent, recorded mainly in middle-aged males with chronic comorbidities presenting as urinary, respiratory, and bacteremia associated with hospitalization, admission to critical care, and invasive procedures. High-level antimicrobial resistance is observed necessitating multiple therapeutic agents and suboptimal bacteriological clearance.

A culture-independent nucleic acid diagnostics method for use in the detection and quantification of Burkholderia cepacia complex contamination in aqueous finished pharmaceutical products

The Burkholderia cepacia complex (Bcc) is the number one bacterial complex associated with contaminated Finished Pharmaceutical Products (FPPs). This has resulted in multiple healthcare related infection morbidity and mortality events in conjunction with significant FPP recalls globally. Current microbiological quality control of FPPs before release for distribution depends on lengthy, laborious, non-specific, traditional culture-dependent methods which lack sensitivity. Here, we present the development of a culture-independent Bcc Nucleic Acid Diagnostic (NAD) method for detecting Bcc contaminants associated with Over-The-Counter aqueous FPPs. The culture-independent Bcc NAD method was validated to be specific for detecting Bcc at different contamination levels from spiked aqueous FPPs. The accuracy in Bcc quantitative measurements was achieved by the high degree of Bcc recovery from aqueous FPPs. The low variation observed between several repeated Bcc quantitative measurements further demonstrated the precision of Bcc quantification in FPPs. The robustness of the culture-independent Bcc NAD method was determined when its accuracy and precision were not significantly affected during testing of numerous aqueous FPP types with different ingredient matrices, antimicrobial preservative components and routes of administration. The culture-independent Bcc NAD method showed an ability to detect Bcc in spiked aqueous FPPs at a concentration of 20 Bcc CFU/mL. The rapid (≤ 4 hours from sample in to result out), robust, culture-independent Bcc NAD method presented provides rigorous test specificity, accuracy, precision, and sensitivity. This method, validated with equivalence to ISO standard ISO/TS 12869:2019, can be a valuable diagnostic tool in supporting microbiological quality control procedures to aid the pharmaceutical industry in preventing Bcc contamination of aqueous FPPs for consumer safety.

Real-Time PCR (qtPCR) to Discover the Fate of Plant Growth-Promoting Rhizobacteria (PGPR) in Agricultural Soils

To optimize the application of plant growth-promoting rhizobacteria (PGPR) in field trials, tracking methods are needed to assess their shelf life and to determine the elements affecting their effectiveness and their interactions with plants and native soil microbiota. This work developed a real-time PCR (qtPCR) method which traces and quantifies bacteria when added as microbial consortia, including five PGPR species: Burkholderia ambifaria, Bacillus amyloliquefaciens, Azotobacter chroococcum, Pseudomonas fluorescens, and Rahnella aquatilis. Through a literature search and in silico sequence analyses, a set of primer pairs which selectively tag three bacterial species (B. ambifaria, B. amyloliquefaciens and R. aquatilis) was retrieved. The primers were used to trace these microbial species in a field trial in which the consortium was tested as a biostimulant on two wheat varieties, in combination with biochar and the mycorrhizal fungus Rhizophagus intraradices. The qtPCR assay demonstrated that the targeted bacteria had colonized and grown into the soil, reaching a maximum of growth between 15 and 20 days after inoculum. The results also showed biochar had a positive effect on PGPR growth. In conclusion, qtPCR was once more an effective method to trace the fate of supplied bacterial species in the consortium when used as a cargo system for their delivery.

Species distribution and antimicrobial susceptibility of Burkholderia cepacia complex isolates in clinical infections: Experience from a tertiary care hospital, Southern India

PURPOSE

Burkholderia cepacia complex (Bcc) is a diverse group of environmental bacteria associated with opportunistic infections. The identification of Bcc using conventional methods poses challenges. Bcc infections are difficult to treat due to intrinsic antibiotic resistance. The study aimed to investigate the species distribution and antimicrobial susceptibility of clinical Bcc isolates.

METHODS

A total of 153 Bcc isolates obtained from clinical samples were analysed. Species identification was carried out using automated methods, including MALDI-TOF MS and VITEK2. Antimicrobial susceptibility testing was performed using the disc diffusion method.

RESULTS

Burkholderia cenocepacia (70.5%) emerged as the most prevalent species, followed by Burkholderia contaminans (9.8%) and Burkholderia cepacia (7.2%). Ventilator-associated pneumonia (38.6%) was the most common infection, followed by sepsis (28.1%). Co-existence of Bcc with other pathogens in many cases suggested potential co-infection scenarios. Antimicrobial susceptibility revealed that ceftazidime, co-trimoxazole and meropenem were the most effective drugs, while levofloxacin proved to be the least effective. Moderate susceptibility was noted to minocycline, with 4.6% of isolates exhibiting multi-drug resistance.

CONCLUSION

This study provides valuable insights into the prevalence, clinical associations, and antibiotic susceptibility of Bcc in India. It highlights the importance of Bcc as a nosocomial pathogen, especially in vulnerable patient populations. The findings contribute to understanding Bcc infections, their distribution, and emphasize the necessity for accurate identification methods in clinical settings.

Surface-Exposed Protein Moieties of Burkholderia cenocepacia J2315 in Microaerophilic and Aerobic Conditions

Burkholderia cepacia complex infections remain life-threatening to cystic fibrosis patients, and due to the limited eradication efficiency of current treatments, novel antimicrobial therapies are urgently needed. Surface proteins are among the best targets to develop new therapeutic strategies since they are exposed to the host's immune system. A surface-shaving approach was performed using Burkholderia cenocepacia J2315 to quantitatively compare the relative abundance of surface-exposed proteins (SEPs) expressed by the bacterium when grown under aerobic and microaerophilic conditions. After trypsin incubation of live bacteria and identification of resulting peptides by liquid chromatography coupled with mass spectrometry, a total of 461 proteins with ≥2 unique peptides were identified. Bioinformatics analyses revealed a total of 53 proteins predicted as localized at the outer membrane (OM) or extracellularly (E). Additionally, 37 proteins were predicted as moonlight proteins with OM or E secondary localization. B-cell linear epitope bioinformatics analysis of the proteins predicted to be OM and E-localized revealed 71 SEP moieties with predicted immunogenic epitopes. The protegenicity higher scores of proteins BCAM2761, BCAS0104, BCAL0151, and BCAL0849 point out these proteins as the best antigens for vaccine development. Additionally, 10 of the OM proteins also presented a high probability of playing important roles in adhesion to host cells, making them potential targets for passive immunotherapeutic approaches. The immunoreactivity of three of the OM proteins identified was experimentally demonstrated using serum samples from cystic fibrosis patients, validating our strategy for identifying immunoreactive moieties from surface-exposed proteins of potential interest for future immunotherapies development.

Burkholderia pseudomallei Complex Subunit and Glycoconjugate Vaccines and Their Potential to Elicit Cross-Protection to Burkholderia cepacia Complex

Burkholderia are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. B. pseudomallei and B. mallei, the etiological agents of melioidosis and glanders, respectively, are the two clinically relevant members of the B. pseudomallei complex (Bpc). The development of vaccines against Bpc species has been accelerated in recent years, resulting in numerous promising subunits and glycoconjugate vaccines incorporating a variety of antigens. However, a second group of pathogenic Burkholderia species exists known as the Burkholderia cepacia complex (Bcc), a group of opportunistic bacteria which tend to affect individuals with weakened immunity or cystic fibrosis. To date, there have been few attempts to develop vaccines to Bcc species. Therefore, the primary goal of this review is to provide a broad overview of the various subunit antigens that have been tested in Bpc species, their protective efficacy, study limitations, and known or suspected mechanisms of protection. Then, we assess the reviewed Bpc antigens for their amino acid sequence conservation to homologous proteins found in Bcc species. We propose that protective Bpc antigens with a high degree of Bpc-to-Bcc sequence conservation could serve as components of a pan-Burkholderia vaccine capable of protecting against both disease-causing groups.

Challenges and mitigation strategies associated with Burkholderia cepacia complex contamination in pharmaceutical manufacturing

Burkholderia cepacia complex (BCC) is a Gram-negative, non-spore-forming bacterium with more than 20 opportunistic pathogenic species, most commonly found in soil and water. Due to their rapid mutation rates, these organisms are adaptable and possess high genomic plasticity. BCC can cause life-threatening infections in immunocompromised individuals, such as those with cystic fibrosis, chronic granulomatous disease, and neonates. BCC contamination is a significant concern in pharmaceutical manufacturing, frequently causing non-sterile product recalls. BCC has been found in purified water, cosmetics, household items, and even ultrasound gel used in veterinary practices. Pharmaceuticals, personal care products, and cleaning solutions have been implicated in numerous outbreaks worldwide, highlighting the risks associated with intrinsic manufacturing site contamination. Regulatory compliance, product safety, and human health protection depend on testing for BCC in pharmaceutical manufacturing. Identification challenges exist, with BCC often misidentified as other bacteria like non-lactose fermenting Escherichia coli or Pseudomonas spp., particularly in developing countries where reporting BCC in pharmaceuticals remains limited. This review comprehensively aims to address the organisms causing BCC contamination, genetic diversity, identification challenges, regulatory requirements, and mitigation strategies. Recommendations are proposed to aid pharmaceutical chemists in managing BCC-associated risks and implementing prevention strategies within manufacturing processes.

Protozoan predation enhances stress resistance and antibiotic tolerance in Burkholderia cenocepacia by triggering the SOS response

Bacterivorous protists are thought to serve as training grounds for bacterial pathogens by subjecting them to the same hostile conditions that they will encounter in the human host. Bacteria that survive intracellular digestion exhibit enhanced virulence and stress resistance after successful passage through protozoa but the underlying mechanisms are unknown. Here we show that the opportunistic pathogen Burkholderia cenocepacia survives phagocytosis by ciliates found in domestic and hospital sink drains, and viable bacteria are expelled packaged in respirable membrane vesicles with enhanced resistance to oxidative stress, desiccation, and antibiotics, thereby contributing to pathogen dissemination in the environment. Reactive oxygen species generated within the protozoan phagosome promote the formation of persisters tolerant to ciprofloxacin by activating the bacterial SOS response. In addition, we show that genes encoding antioxidant enzymes are upregulated during passage through ciliates increasing bacterial resistance to oxidative radicals. We prove that suppression of the SOS response impairs bacterial intracellular survival and persister formation within protists. This study highlights the significance of protozoan food vacuoles as niches that foster bacterial adaptation in natural and built environments and suggests that persister switch within phagosomes may be a widespread phenomenon in bacteria surviving intracellular digestion.

Identification of a system for hydroxamate xenosiderophore-mediated iron transport in Burkholderia cenocepacia

One of the mechanisms employed by the opportunistic pathogen Burkholderia cenocepacia to acquire the essential element iron is the production and release of two ferric iron chelating compounds (siderophores), ornibactin and pyochelin. Here we show that B. cenocepacia is also able to take advantage of a range of siderophores produced by other bacteria and fungi ('xenosiderophores') that chelate iron exclusively by means of hydroxamate groups. These include the tris-hydroxamate siderophores ferrioxamine B, ferrichrome, ferricrocin and triacetylfusarinine C, the bis-hydroxamates alcaligin and rhodotorulic acid, and the monohydroxamate siderophore cepabactin. We also show that of the 24 TonB-dependent transporters encoded by the B. cenocepacia genome, two (FhuA and FeuA) are involved in the uptake of hydroxamate xenosiderophores, with FhuA serving as the exclusive transporter of iron-loaded ferrioxamine B, triacetylfusarinine C, alcaligin and rhodotorulic acid, while both FhuA and FeuA are able to translocate ferrichrome-type siderophores across the outer membrane. Finally, we identified FhuB, a putative cytoplasmic membrane-anchored ferric-siderophore reductase, as being obligatory for utilization of all of the tested bis- and tris-hydroxamate xenosiderophores apart from alcaligin.

A Case Report of Necrotizing Pneumonia Due to Burkholderia cepacia Syndrome

Burkholderia cepacia ​​​​​​(B. cepacia) complex is a highly resistant gram-negative pathogen known to cause lung infection in cystic fibrosis, chronic granulomatous disease, and immunocompromised patients. However, it may rarely infect immunocompetent patients as well. Here, we present the case of a 30-year-old male patient who was treated for B. cepacia pneumonia in the hospital, discharged with oral antibiotics, and returned two months later with recurring B. cepacia pneumonia and bacteremia. The patient rapidly declined over the next 24 hours and expired in the intensive care unit. This case is significant as it is one of very few published cases of cepacia syndrome in a patient with no evidence of immunodeficiency. In conclusion, cases of B. cepacia pneumonia must be monitored vigilantly for progression to cepacia syndrome, even in immunocompetent patients. Additional studies regarding optimized antibiotic regimens and effective treatment modalities for B. cepacia infection are warranted.

Bioinformatics and immunoinformatics assisted multiepitope vaccine construct against Burkholderia anthina

Burkholderia anthina is a pathogenic bacterial species belonging to the Burkholderiaceae family and it is mainly considered the etiological agent of chronic obstructive pulmonary diseases associated with cystic fibrosis, due to being intrinsic antibiotic resistant making it difficult to treat pulmonary infections. Hence increased rate of antibiotic-resistant bacterial species vaccine development is the priority to tackle this problem. In research work, we designed a multi-epitope-based vaccine construct against B. anthina using reverse vaccinology immunoinformatics and biophysical approaches. Based on the subtractive proteomic screening of core proteins we identified 3 probable antigenic proteins and good vaccine targets namely, type VI secretion system tube protein hcp Burkholderia, fimbria/pilus periplasmic chaperone and fimbrial biogenesis outer membrane usher protein. The selected 3 proteins were used for B and B cells B-derived T-cell epitopes prediction. In epitopes prediction, different epitopes were predicted with various lengths and percentile scores and subjected to further immunoinformatics analysis. In immunoinformatics screening a total number of 06, IDDGNANAL, KTVKPDPRY, SEVESGSAP, YGGDLTVEV, SVSHDTNGR, and GSKADGYQR epitopes were considered good vaccine target candidates and shortlisted for vaccine construct designing. The vaccine construct was designed by joining selected epitopes with the help of a GPGPG linker and additionally linked with cholera toxin b subunit adjuvant to increase the efficacy of the vaccine construct the sequence of the said adjuvant were retrieved from protein data bank through its (PDB ID: 5ELD). The designed vaccine construct was evaluated for its physiochemical properties analysis in which we reported that the vaccine construct comprises 216 amino acids with a molecular weight of 22.37499 kilo Dalton, 15.55 instability index (II) is computed, and this classifies that the vaccine construct is properly stable. VaxiJen v2.0 web server predicted that the vaccine construct is probable antigenic in nature with 0.6320 predicted value. Furthermore AllerTOP v. 2.0 tool predicted that the designed vaccine construct is non allergic in nature. Molecular docking analysis was done for analysis of the binding affinity of the vaccine construct with TLR-2 (PDB ID: 6NIG), the docking results predicted 799.2 kcal/mol binding energy score that represents the vaccine construct has a good binding ability with TLR-2. Moreover, molecular dynamic simulation analysis results revealed that the vaccine construct and immune cell receptor has proper binding stability over various environmental condition, i.e. change in pressure range, temperature, and motion. After each analysis, we observed that the vaccine construct is safe stable, and probably antigenic and could generate an immune response against the target pathogen but in the future, experimental analysis is still needed to verify in silico base results.

Septic Transfusion Reactions Involving Burkholderia cepacia Complex: A Review

This review was conducted to assess the global incidence of transfusion-transmitted infections (TTIs) caused by contamination of blood components with the Burkholderia cepacia complex (Bcc). Our search encompassed various specialized databases such as Medline/PubMed, Web of Science, Scopus, Scielo, ScienceDirect, and ClinicalKey. An analysis of the literature revealed a total of eleven reported cases where blood components contaminated with Bcc had been transfused, resulting in sepsis among the affected patients. Of these cases, eight were documented in the literature, while the remaining three occurred within the institution involving the authors of this review. A comparative examination was conducted, considering factors such as primary diagnosis, transfused blood component, time elapsed between transfusion and manifestation of symptoms, administration of antibiotics, and final outcome. Interestingly, regardless of the storage temperature, all blood components were found to be susceptible to Bcc contamination. Furthermore, the cases investigated revealed diverse sources of contamination, and it was observed that all the affected patients had compromised immune systems due to underlying illnesses. Based on these findings, a series of preventive strategies were derived to mitigate and decrease the occurrence of similar cases.

Infected aortic endograft with an unusual microbe, Burkholderia cepacia

With the growing use of endovascular aortic repair for aortic aneurysm pathology, multiple cases have been reported of associated endovascular graft infections. Explantation of the infected endograft and the revascularization procedure performed should be individualized with attention to the offending organism. We present the cases of two patients who underwent endovascular aortic repair with the same endograft and developed a graft infection with Burkholderia cepacia, a gram-negative organism with low virulence. Both endografts cultured Burkholderia cepacia complex; however, the organisms were genetically tested and found to be separate, unrelated strains. Both patients underwent successful explantation and revascularization procedures without any surgical-related complications to date.

Biofilm formation is correlated with low nutrient and simulated microgravity conditions in a Burkholderia isolate from the ISS water processor assembly

The International Space Station (ISS) Water Processor Assembly (WPA) experiences intermittent dormancy in the WPA wastewater tank during water recycling events which promotes biofilm formation within the system. In this work we aimed to gain a deeper understanding of the impact of nutrient limitation on bacterial growth and biofilm formation under microgravity in support of biofilm mitigation efforts in exploration water recovery systems. A representative species of bacteria that is commonly cultured from the ISS WPA was cultured in an WPA influent water ersatz formulation tailored for microbiological studies. An isolate of Burkholderia contaminans was cultured under a simulated microgravity (SμG) treatment in a vertically rotating high-aspect rotating vessel (HARV) to create the low shear modeled microgravity (LSMMG) environment on a rotating wall vessel (RWV), with a rotating control (R) in the horizontal plane at the predetermined optimal rotation per minute (rpm) speed of 20. Over the course of the growth curve, the bacterial culture in ersatz media was harvested for bacterial counts, and transcriptomic and nutrient content analyses. The cultures under SμG treatment showed a transcriptomic signature indicative of nutrient stress and biofilm formation as compared to the R control treatment. Further analysis of the WPA ersatz over the course of the growth curve suggests that the essential nutrients of the media were consumed faster in the early stages of growth for the SμG treatment and thus approached a nutrient limited growth condition earlier than in the R control culture. The observed limited nutrient response may serve as one element to explain a moderate enhancement of adherent biofilm formation in the SμG treatment after 24 h. While nutrients levels can be modulated, one implication of this investigation is that biofilm mitigation in the ISS environment could benefit from methods such as mixing or the maintenance of minimum flow within a dormant water system in order to force convection and offset the response of microbes to the secondary effects of microgravity.

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.

Endophthalmitis caused by Burkholderia cepacia complex (BCC): clinical characteristics, antibiotic susceptibilities, and treatment outcomes

PURPOSE

To report the clinical characteristics, antibiotic susceptibilities, and review the literature of Burkholderia cepacia complex (BCC) associated endophthalmitis.

STUDY DESIGN

Retrospective, observational case series.

METHODS

Clinical and microbiology records were reviewed for patients evaluated at the Bascom Palmer Eye Institute and diagnosed wisth culture-confirmed endophthalmitis due to BCC. Antibiotic susceptibility profiles were generated using standard microbiologic protocols via an automated VITEK system.

RESULTS

Endophthalmitis associated with BCC was diagnosed in three patients. Infection occurred in the setting of post-penetrating keratoplasty (PKP), glaucoma filtering surgery, and suspected trauma. All isolates demonstrated in vitro susceptibility to ceftazidime and meropenem. Presenting visual acuity (VA) ranged from hand motion to light perception. Initial treatment strategies included intravitreal ceftazidime (2.25 mg/0.1 mL) and vancomycin (1.0 mg/0.1 mL) injections with fortified topical antibiotics in 2 patients, and surgical debridement of a corneoscleral melt with patch graft along with both topical fortified antibiotics oral antibiotics in the third patient. In all 3 patients, there was no VA improvement at last follow-up, as 2 eyes ultimately underwent enucleation and 1 eye exhibited phthisis bulbi at last follow-up. BCC related endophthalmitis was reviewed among 13 reports. Treatment outcomes were generally poor and antibiotic resistance was common. These BCC isolates cases demonstrated broad resistance patterns, with susceptibilities to ceftazidime (58%), ciprofloxacin (53%), and gentamicin (33%).

CONCLUSIONS

Endophthalmitis caused by B. cepacia is a rare clinical entity with generally poor visual outcomes despite prompt treatment with appropriate antibiotics.

Slc11 Synapomorphy: A Conserved 3D Framework Articulating Carrier Conformation Switch

Transmembrane carriers of the Slc11 family catalyze proton (H+)-dependent uptake of divalent metal ions (Me2+) such as manganese and iron-vital elements coveted during infection. The Slc11 mechanism of high-affinity Me2+ cell import is selective and conserved between prokaryotic (MntH) and eukaryotic (Nramp) homologs, though processes coupling the use of the proton motive force to Me2+ uptake evolved repeatedly. Adding bacterial piracy of Nramp genes spread in distinct environmental niches suggests selective gain of function that may benefit opportunistic pathogens. To better understand Slc11 evolution, Alphafold (AF2)/Colabfold (CF) 3D predictions for bacterial sequences from sister clades of eukaryotic descent (MCb and MCg) were compared using both native and mutant templates. AF2/CF model an array of native MCb intermediates spanning the transition from outwardly open (OO) to inwardly open (IO) carriers. In silico mutagenesis targeting (i) a set of (evolutionarily coupled) sites that may define Slc11 function (putative synapomorphy) and (ii) residues from networked communities evolving during MCb transition indicates that Slc11 synapomorphy primarily instructs a Me2+-selective conformation switch which unlocks carrier inner gate and contributes to Me2+ binding site occlusion and outer gate locking. Inner gate opening apparently proceeds from interaction between transmembrane helix (h) h5, h8 and h1a. MCg1 xenologs revealed marked differences in carrier shape and plasticity, owing partly to an altered intramolecular H+ network. Yet, targeting Slc11 synapomorphy also converted MCg1 IO models to an OO state, apparently mobilizing the same residues to control gates. But MCg1 response to mutagenesis differed, with extensive divergence within this clade correlating with MCb-like modeling properties. Notably, MCg1 divergent epistasis marks the emergence of the genus Bordetella-Achromobacter. Slc11 synapomorphy localizes to the 3D areas that deviate least among MCb and MCg1 models (either IO or OO) implying that it constitutes a 3D network of residues articulating a Me2+-selective carrier conformation switch which is maintained in fast-evolving clades at the cost of divergent epistatic interactions impacting carrier shape and dynamics.

Specific biomarker mining and rapid detection of Burkholderia cepacia complex by recombinase polymerase amplification

Objective

To mine specific proteins and their protein-coding genes as suitable molecular biomarkers for the Burkholderia cepacia Complex (BCC) bacteria detection based on mega analysis of microbial proteomic and genomic data comparisons and to develop a real-time recombinase polymerase amplification (rt-RPA) assay for rapid isothermal screening for pharmaceutical and personal care products.

Methods

We constructed an automatic screening framework based on Python to compare the microbial proteomes of 78 BCC strains and 263 non-BCC strains to identify BCC-specific protein sequences. In addition, the specific protein-coding gene and its core DNA sequence were validated in silico with a self-built genome database containing 158 thousand bacteria. The appropriate methodology for BCC detection using rt-RPA was evaluated by 58 strains in pure culture and 33 batches of artificially contaminated pharmaceutical and personal care products.

Results

We identified the protein SecY and its protein-coding gene secY through the automatic comparison framework. The virtual evaluation of the conserved region of the secY gene showed more than 99.8% specificity from the genome database, and it can distinguish all known BCC species from other bacteria by phylogenetic analysis. Furthermore, the detection limit of the rt-RPA assay targeting the secY gene was 5.6 × 102 CFU of BCC bacteria in pure culture or 1.2 pg of BCC bacteria genomic DNA within 30 min. It was validated to detect <1 CFU/portion of BCC bacteria from artificially contaminated samples after a pre-enrichment process. The relative trueness and sensitivity of the rt-RPA assay were 100% in practice compared to the reference methods.

Conclusion

The automatic comparison framework for molecular biomarker mining is straightforward, universal, applicable, and efficient. Based on recognizing the BCC-specific protein SecY and its gene, we successfully established the rt-RPA assay for rapid detection in pharmaceutical and personal care products.

Antimicrobial Susceptibility Profiles and Key Determinants for Mortality in Burkholderia cepacia Complex Infections

Objective

We aimed to define the clinical features and antimicrobial susceptibility profiles of Burkholderia cepacia complex infections and to determine the predictors for mortality.

Materials and Methods

Our single-center retrospective study included patients with nosocomial B. cepacia complex infection between 2018 and 2022. We evaluated the predictors of 14-day and 28-day mortality by analyzing clinical and microbiological data.

Results

A total of 87 patients were included. Most infections (79.3%) occurred in the intensive care units (ICUs). Among B. cepacia complex isolates, 74.7% were susceptible to trimethoprim-sulfamethoxazole, 70.3% to levofloxacin, 50% to meropenem, and 23.4% to ceftazidime. The rates of 14-day mortality, 28-day mortality, and in-hospital mortality were 41.3% (n=36), 52.8% (n=46), and 64.3% (n=56), respectively. Multivariate analysis revealed neutrophil/lymphocyte ratio (NLR) (odds ratio [OR]=1.05, p=0.024), platelet count (OR=1.00, p=0.011), creatinine (OR=2.14, p=0.006), and aspartate aminotransferase (AST) (OR=1.02, p=0.028) as predictors for 14-day mortality. In addition to NLR (OR=1.07, p=0.014), platelet count (OR=1.00, p=0.039), creatinine (OR=2.05, p=0.008), and AST (OR=1.02, p=0.035), procalcitonin (OR=1.05, p=0.049) was also found as an independent predictor for 28-day mortality. In receiver operating characteristic (ROC) curve analysis for predicting 14-day mortality, area under the ROC curve (AUC) values were 0.684 (p=0.003) in NLR, 0.719 (p<0.001) in platelet count, 0.673 (p=0.003) in procalcitonin, 0.743 (p<0.001) in creatinine, and 0.700 (p<0.001) in AST. In ROC curve analysis for predicting 28-day mortality, AUC values were 0.674 (p=0.002) in NLR, 0.651 (p=0.010) in platelet count, 0.638 (p=0.020) in procalcitonin, 0.730 (p<0.001) in creatinine, and 0.692 (p=0.001) in AST.

Conclusion

Increasing antibiotic resistance and higher mortality rates justify that B. cepacia complex is a significant threat to hospitalized patients, especially in ICUs. Elevated levels of NLR, AST, creatinine, procalcitonin, and decreased platelet may predict poor clinical outcomes and could help clinicians in the management of this notorious bacterial pathogen.

A study on the occurrence of Burkholderia cepacia complex in ultrasound gels used in different veterinary clinical settings in India

Burkholderia cepacia complex (Bcc) organisms are emerging multidrug-resistant pathogens. They are opportunistic and cause severe diseases in humans that may result in fatal outcomes. They are mainly reported as nosocomial pathogens, and transmission often occurs through contaminated pharmaceutical products. From 1993 to 2019, 14 Bcc outbreaks caused by contaminated ultrasound gels (USGs) have been reported in several countries, including India. We screened a total of 63 samples of USGs from various veterinary and human clinical care centers across 17 states of India and isolated 32 Bcc strains of Burkholderia cenocepacia (46.8%), B. cepacia (31.3%), B. pseudomultivorans (18.8%) and B. contaminans (3.1%) species. Some isolates were co-existent in a single ultrasound gel sample. The isolation from unopened gel bottles revealed the intrinsic contamination from manufacturing sites. The MALDI-TOF analysis to identify the Bcc at the species level was supported by the partial sequencing of the recA gene for accurate species identification. The phylogenetic analysis revealed that isolates shared clades with human clinical isolates, which is an important situation because of the possible infections of Bcc by USGs both in humans and animals. The pulsed field gel electrophoresis (PFGE) typing identified the genetic variation among the Bcc isolates present in the USGs. The findings indicated USGs as the potential source of Bcc species.

Validation of a Rapid Microbiological Method for the Detection and Quantification of the Burkholderia cepacia Complex in an Antacid Oral Suspension

BACKGROUND

Despite the broad adoption of Soleris® technology in the food industry as semiquantitative method, it is almost completely unexplored in the pharmaceutical industry as a quantitative method for quantification of Burkholderia cepacia complex (Bcc).

OBJECTIVE

The efficacy of an automated growth-based system for a quantitative determination of the Bcc in an antacid oral suspension was studied. The main purpose of this validation study was to prove that the alternative method's entire performance is not inferior to the conventional method for a quantitative determination of Bcc.

METHOD

The antacid oral suspension's preservatives were neutralized, leading to the Burkholderia complex's recovery by means of the alternative method and the reference method. A calibration curve was generated for each strain by plotting DTs relative to the corresponding log CFU values. An equivalence of results was done through the construction of calibration curves that allowed the establishment of numerically equivalent results between the enumeration data from the reference method and the alternative method.

RESULTS

Thus following the guidelines of USP, essential validation parameters were shown, such as equivalence of results (CC >0.95), linearity (R2 >0.9025), accuracy (% recovery >70%), operating range, precision and ruggedness (DS <5 and CV <35%), specificity (inclusivity and exclusivity), limit of detection (LOD), and limit of quantification (LOQ).

CONCLUSIONS

It was shown that all the test results obtained from the alternative method were in statistical agreement with the standard method. Thus this new technology was found to meet all the validation criteria needed to be considered as an alternative method for the quantification of the Burkholderia complex in the antacid oral suspension tested.

HIGHLIGHTS

As outlined in USP chapter <1223> and demonstrated in this research the implementation of alternative methods can offer benefits in execution and automation while improving accuracy, sensitivity, and precision and can reduce the microbiological process time compared to the traditional ones.

A Burkholderia stabilis outbreak associated with the use of ultrasound gel in multiple healthcare centres in Montréal, Canada, May-October 2021

Background

Burkholderia stabilis is a non-fermenting, gram-negative bacteria that has previously been implicated in multiple nosocomial outbreaks through the use of contaminated medical devices and substances. This article reports on an outbreak of B. stabilis infections and colonizations, involving 11 patients from five acute care hospitals in Montréal, Canada.

Methods

One sample was not available for testing, but the remaining 10 isolates (91%) were sent for phylogenetic testing. Medical materials and the patients' environments were also sampled and cultured. Samples were tested using pulsed field gel electrophoresis and multilocus sequence typing.

Results

The outbreak was found to be associated with the use of intrinsically contaminated non-sterile ultrasound gel. Relatedness of the gel's and the patients' B. stabilis strains was demonstrated using gel electrophoresis and multilocus sequence typing analyses. The investigation was concluded with a prompt recall of the product, and the outbreak was declared over by the end of October 2021.

Conclusion

Contaminated non-sterile gel caused infections and pseudo-infections in several patients.

Endophthalmitis caused by Burkholderia cepacia complex (BCC): Clinical characteristics, antibiotic susceptibilities, and treatment outcomes

Purpose

To report the clinical characteristics, antibiotic susceptibilities, and review the literature of Burkholderia cepacia complex (BCC) associated endophthalmitis.

Study design

Retrospective, observational case series.

Methods

Clinical and microbiology records were reviewed for patients evaluated at the Bascom Palmer Eye Institute and diagnosed with culture-confirmed endophthalmitis due to BCC. Antibiotic susceptibility profiles were generated using standard microbiologic protocols via an automated VITEK system.

Results

Endophthalmitis associated with BCC was diagnosed in three patients. Infection occurred in the setting of post-penetrating keratoplasty (PKP), glaucoma filtering surgery, and suspected trauma. All isolates demonstrated in vitro susceptibility to ceftazidime and meropenem. Presenting visual acuity (VA) ranged from hand motion to light perception. Initial treatment strategies included intravitreal ceftazidime (2.25 mg/0.1 mL) and vancomycin (1.0 mg/0.1mL) injections with fortified topical antibiotics in 2 patients, and surgical debridement of a corneoscleral melt with patch graft along with both topical fortified antibiotics oral antibiotics in the third patient. In all 3 patients, there was no VA improvement at last follow-up, as 2 eyes ultimately underwent enucleation and 1 eye exhibited phthisis bulbi at last follow-up. BCC related endophthalmitis was reviewed among 13 reports. Treatment outcomes were generally poor and antibiotic resistance was common. These BCC isolates cases demonstrated broad resistance patterns, with susceptibilities to ceftazidime (58%), ciprofloxacin (53%), and gentamicin (33%).

Conclusions

Endophthalmitis caused by B. cepacia is a rare clinical entity with generally poor visual outcomes despite prompt treatment with appropriate antibiotics.

Community-Acquired burkholderia cepacia complex (BCC) pneumonia in a lung cancer patient on erlotinib

Community-acquired Burkholderia cepacia pneumonia is uncommon. We report a 32-year-old female who was on oral erlotinib, a tyrosine kinase inhibitor, for 2 years for her lung cancer and developed community-acquired Burkholderia cepacia pneumonia, which was confirmed by blood culture. The patient improved with antibiotics.

In Vitro Activity of Finafloxacin against Panels of Respiratory Pathogens

This study determined the in vitro activity of finafloxacin against panels of bacterial strains, representative of those associated with infection in cystic fibrosis patients and predominately isolated from clinical cases of respiratory disease. Many of these isolates were resistant to various antimicrobials evaluated including the aminoglycosides, cephalosporins, carbapenems and fluoroquinolones. Broth microdilution assays were performed at neutral and acidic pH, to determine antimicrobial activity. Finafloxacin demonstrated superior activity at reduced pH for all of the bacterial species investigated, highlighting the requirement to determine the activity of antimicrobials in host-relevant conditions.

Burkholderia contaminans Bacteriophage CSP3 Requires O-Antigen Polysaccharides for Infection

The Burkholderia cepacia complex is a group of opportunistic pathogens that cause both severe acute and chronic respiratory infections. Due to their large genomes containing multiple intrinsic and acquired antimicrobial resistance mechanisms, treatment is often difficult and prolonged. One alternative to traditional antibiotics for treatment of bacterial infections is bacteriophages. Therefore, the characterization of bacteriophages infective for the Burkholderia cepacia complex is critical to determine their suitability for any future use. Here, we describe the isolation and characterization of novel phage, CSP3, infective against a clinical isolate of Burkholderia contaminans. CSP3 is a new member of the Lessievirus genus that targets various Burkholderia cepacia complex organisms. Single nucleotide polymorphism (SNP) analysis of CSP3-resistant B. contaminans showed that mutations to the O-antigen ligase gene, waaL, consequently inhibited CSP3 infection. This mutant phenotype is predicted to result in the loss of cell surface O-antigen, contrary to a related phage that requires the inner core of the lipopolysaccharide for infection. Additionally, liquid infection assays showed that CSP3 provides suppression of B. contaminans growth for up to 14 h. Despite the inclusion of genes that are typical of the phage lysogenic life cycle, we saw no evidence of CSP3's ability to lysogenize. Continuation of phage isolation and characterization is crucial in developing large and diverse phage banks for global usage in cases of antibiotic-resistant bacterial infections. IMPORTANCE Amid the global antibiotic resistance crisis, novel antimicrobials are needed to treat problematic bacterial infections, including those from the Burkholderia cepacia complex. One such alternative is the use of bacteriophages; however, a lot is still unknown about their biology. Bacteriophage characterization studies are of high importance for building phage banks, as future work in developing treatments such as phage cocktails should require well-characterized phages. Here, we report the isolation and characterization of a novel Burkholderia contaminans phage that requires the O-antigen for infection, a distinct phenotype seen among other related phages. Our findings presented in this article expand on the ever-evolving phage biology field, uncovering unique phage-host relationships and mechanisms of infection.

Identification by Reverse Vaccinology of Three Virulence Factors in Burkholderia cenocepacia That May Represent Ideal Vaccine Antigens

The Burkholderia cepacia complex comprises environmental and clinical Gram-negative bacteria that infect particularly debilitated people, such as those with cystic fibrosis. Their high level of antibiotic resistance makes empirical treatments often ineffective, increasing the risk of worst outcomes and the diffusion of multi-drug resistance. However, the discovery of new antibiotics is not trivial, so an alternative can be the use of vaccination. Here, the reverse vaccinology approach has been used to identify antigen candidates, obtaining a short-list of 24 proteins. The localization and different aspects of virulence were investigated for three of them-BCAL1524, BCAM0949, and BCAS0335. The three antigens were localized in the outer membrane vesicles confirming that they are surface exposed. We showed that BCAL1524, a collagen-like protein, promotes bacteria auto-aggregation and plays an important role in virulence, in the Galleria mellonella model. BCAM0949, an extracellular lipase, mediates piperacillin resistance, biofilm formation in Luria Bertani and artificial sputum medium, rhamnolipid production, and swimming motility; its predicted lipolytic activity was also experimentally confirmed. BCAS0335, a trimeric adhesin, promotes minocycline resistance, biofilm organization in LB, and virulence in G. mellonella. Their important role in virulence necessitates further investigations to shed light on the usefulness of these proteins as antigen candidates.

Propidium Monoazide (PMAxx)-Recombinase Polymerase Amplification Exo (RPA Exo) Assay for Rapid Detection of Burkholderia cepacia Complex in Chlorhexidine Gluconate (CHX) and Benzalkonium Chloride (BZK) Solutions

Both sterile and non-sterile pharmaceutical products, which include antiseptics, have been recalled due to Burkholderia cepacia complex (BCC) contamination. Therefore, minimizing the frequency of outbreaks may be conducive to the development of a quick and sensitive approach that can distinguish between live and dead loads of BCC. We have assessed an exo probe-based recombinase polymerase amplification (RPA) with 10 µM propidium monoazide (PMAxx) for selective detection of live/dead BCC cells in various concentrations of antiseptics (i.e., chlorhexidine gluconate (CHX) and benzalkonium chloride (BZK) solutions) after 24 h. The optimized assay conducted using a set of primer-probes targeting gbpT was performed at 40 °C for 20 min and shows a detection limit of 10 pg/µL of genomic DNA from B. cenocepacia J2315, equivalent to 10⁴ colony-forming units (CFU/mL). The specificity of a newly designed primer and probe was 80% (20 negatives out of 25). The readings for total cells (i.e., without PMAxx) from 200 µg/mL CHX using PMAxx-RPA exo assay was 310 relative fluorescence units (RFU), compared to 129 RFU with PMAxx (i.e., live cells). Furthermore, in 50-500 µg/mL BZK-treated cells, a difference in the detection rate was observed between the PMAxx-RPA exo assay in live cells (130.4-459.3 RFU) and total cells (207.82-684.5 RFU). This study shows that the PMAxx-RPA exo assay appears to be a valid tool for the simple, rapid and presumptive detection of live BCC cells in antiseptics, thereby ensuring the quality and safety of pharmaceutical products.

Metabolomic profiling reveals bacterial metabolic adaptation strategies and new metabolites

How has metabolomics helped our understanding of infectious diseases? With the threat of antimicrobial resistance to human health around the world, metabolomics has emerged as a powerful tool to comprehensively characterize metabolic pathways to identify new drug targets. However, its output is constrained to known metabolites and their metabolic pathways. Recent advances in instrumentation, methodologies, and computational mass spectrometry have accelerated the use of metabolomics to understand pathogen-host metabolic interactions. This short review discusses a selection of recent publications using metabolomics in infectious/bacterial diseases. These studies unravel the links between metabolic adaptations to environments and host metabolic responses. Moreover, they highlight the importance of enzyme function and metabolite characterization in identifying new drug targets and biomarkers, as well as precision medicine in monitoring therapeutics and diagnosing diseases.

Genome Sequences of Three Common Bacterial Isolates from Wastewater from the Water Processor Assembly at the International Space Station

Bacteria from the genera Burkholderia, Ralstonia, and Methylobacterium were consistently detected in water of the life support systems at the International Space Station. Here, we report complete genomes of recent isolates that are representative of these genera to support future studies in biofilm and wastewater treatment in space habitats.

Systematic review of ultrasound gel associated Burkholderia cepacia complex outbreaks: Clinical presentation, sources and control of outbreak

BACKGROUND

Burkholderia cepacia complex (Bcc) is an emerging opportunistic pathogen among immunocompromised patients. It frequently contaminates saline, fluids and ultrasound (US) gel used in hospitals. This systematic review was conducted to analyze Bcc outbreaks due to ultrasound (US) gel for better management of these outbreaks.

METHODS

As per PRISMA guidelines, electronic databases "Embase" and "Pubmed" and "Web of sciences" were searched from 1991 to April, 2021 to identify studies causing Burkholderia spp outbreak due to contamination of US gels.

RESULTS

The search identified 14 outbreak reports that met our inclusion criteria. Bacteremia was the most common clinical presentation in ten studies followed by urinary tract infections in 4 studies. In most of the studies B. cepacia was the most common isolated organism. Other members like B. ambifaria, B. contaminans, and B. stabilis caused outbreaks in two studies. Pulsed field gel electrophoresis and multilocus sequence typing were commonly employed methods to study the clonal association. In 8 outbreaks, intrinsic contamination of the gel, that is, contamination from manufacturing site, was present and 4 studies, extrinsic contamination, that is, contamination from environment was responsible for outbreak.

CONCLUSION

This review highlights the importance of US gel as a source of outbreak in health-care facilities. Ensuring sterility of US gel, sound epidemiological investigation of outbreak and prompt response by infection control team can prevent these outbreaks.

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.

Rapid detection of Burkholderia cepacia complex carrying the 16S rRNA gene in clinical specimens by recombinase-aided amplification

The Burkholderia cepacia complex (BCC) is a group of opportunistic pathogens, including Burkholderia cepacia, Burkholderia multivorans, Burkholderia vietnamiensis and Burkholderia ambifaria, which can cause severe respiratory tract infections and lead to high mortality rates among humans. The early diagnosis and effective treatment of BCC infection are therefore crucial. In this study, a novel and rapid recombinase-aided amplification (RAA) assay targeting the 16S rRNA gene was developed for BCC detection. The protocol for this RAA assay could be completed in 10 min at 39°C, with a sensitivity of 10 copies per reaction and no cross-reactivity with other pathogens. To characterize the effectiveness of the RAA assay, we further collected 269 clinical samples from patients with bacterial pneumonia. The sensitivity and specificity of the RAA assay were 100% and 98.5%, respectively. Seven BCC-infected patients were detected using the RAA assay, and three BCC strains were isolated from the 269 clinical samples. Our data showed that the prevalence of BCC infection was 2.60%, which is higher than the 1.40% reported in previous studies, suggesting that high sensitivity is vital to BCC detection. We also screened a patient with B. vietnamiensis infection using the RAA assay in clinic, allowing for appropriate treatment to be initiated rapidly. Together, these data indicate that the RAA assay targeting the 16S rRNA gene can be applied for the early and rapid detection of BCC pathogens in patients with an uncharacterized infection who are immunocompromised or have underlying diseases, thereby providing guidance for effective treatment.

Burkholderia cepacia Complex Outbreak Linked to a No-Rinse Cleansing Foam Product, United States - 2017-2018

In March 2018, the US Food and Drug Administration (FDA), US Centers for Disease Control and Prevention, California Department of Public Health, Los Angeles County Department of Public Health and Pennsylvania Department of Health initiated an investigation of an outbreak of Burkholderia cepacia complex (Bcc) infections. Sixty infections were identified in California, New Jersey, Pennsylvania, Maine, Nevada and Ohio. The infections were linked to a no-rinse cleansing foam product (NRCFP), produced by Manufacturer A, used for skin care of patients in healthcare settings. FDA inspected Manufacturer A's production facility (manufacturing site of over-the-counter drugs and cosmetics), reviewed production records and collected product and environmental samples for analysis. FDA's inspection found poor manufacturing practices. Analysis by pulsed-field gel electrophoresis confirmed a match between NRCFP samples and clinical isolates. Manufacturer A conducted extensive recalls, FDA issued a warning letter citing the manufacturer's inadequate manufacturing practices, and federal, state and local partners issued public communications to advise patients, pharmacies, other healthcare providers and healthcare facilities to stop using the recalled NRCFP. This investigation highlighted the importance of following appropriate manufacturing practices to minimize microbial contamination of cosmetic products, especially if intended for use in healthcare settings.

Specific Detection and Enumeration of Burkholderia cepacia Complex by Flow Cytometry Using a Fluorescence-Labeled Oligonucleotide Probe

Burkholderia cepacia complex (BCC) contamination has resulted in recalls of non-sterile pharmaceutical products. The fast, sensitive, and specific detection of BCC is critical for ensuring the quality and safety of pharmaceutical products. In this study, a rapid flow cytometry-based detection method was developed using a fluorescence-labeled oligonucleotide Kef probe that specifically binds a KefB/KefC membrane protein sequence within BCC. Optimal conditions of a 1 nM Kef probe concentration at a 60 °C hybridization temperature for 30 min were determined and applied for the flow cytometry assay. The true-positive rate (sensitivity) and true-negative rate (specificity) of the Kef probe assay were 90% (18 positive out of 20 BCC species) and 88.9% (16 negative out of 18 non-BCC), respectively. The detection limit for B. cenocepacia AU1054 with the Kef probe flow cytometry assay in nuclease-free water was 1 CFU/mL. The average cell counts using the Kef probe assay from a concentration of 10 μg/mL chlorhexidine gluconate and 50 μg/mL benzalkonium chloride were similar to those of the RAPID-B total plate count (TPC). We demonstrate the potential of Kef probe flow cytometry as a more sensitive alternative to culture-based methods for detecting BCC in non-sterilized pharmaceutical raw materials and products with regards to water-based environments.