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Journal of Infection in Developing... Apr 2022Ralstonia pickettii infections are rare and may be mistaken for other bacteria. This study aims to report a hospital outbreak of R. pickettii at a tertiary hospital,...
INTRODUCTION
Ralstonia pickettii infections are rare and may be mistaken for other bacteria. This study aims to report a hospital outbreak of R. pickettii at a tertiary hospital, which was initially misidentified as Ralstonia insidiosa, along with its clinical consequences.
METHODOLOGY
A bacteraemia outbreak occurred between August 14 and October 4, 2019, infecting 22 patients admitted to diverse intensive care units. All isolates were identified with the use of the automated VITEK 2 Compact system and were then subjected to a microbial identification system, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Bacterial identification and genomic DNA typing was made using pulsed-field gel electrophoresis. Investigation covered all potential sources of the outbreak.
RESULTS
An index patient and five additional patients developed fever while receiving care. Blood cultures of these patients yielded R. insidiosa by the VITEK 2 Compact system. Culture isolates were then submitted to a reference centre for confirmation by the MALDI-TOF MS system, where the bacterium turned out to be R. pickettii. No pathogen was isolated in the commercial products except for three samples of unopened sterile distilled water. Despite its discontinuation, 16 new cases were identified, in which blood cultures grew R. pickettii by the MALDI-TOF MS system. Attempts to uncover the source of the outbreak failed. Clinical manifestation was confined to fever in all the patients.
CONCLUSIONS
During this outbreak, R. pickettii infections ran a relatively mild course without clinical deterioration or mortality, possibly due to low virulence.
Topics: Bacteremia; Disease Outbreaks; Electrophoresis, Gel, Pulsed-Field; Humans; Ralstonia pickettii; Sepsis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 35544634
DOI: 10.3855/jidc.15159 -
Research in Microbiology 2021Ralstonia pickettii are ubiquitous in water environments. Members of this species are frequently, but not always, resistant to both gentamicin and arsenite. Gentamicin...
Ralstonia pickettii are ubiquitous in water environments. Members of this species are frequently, but not always, resistant to both gentamicin and arsenite. Gentamicin and arsenite co-resistance and the putative molecular mechanisms were investigated. A group of 37 R. pickettii strains isolated from drinking water and hospital wastewater were characterized for gentamicin and arsenite resistance phenotypes, the number and size of plasmids, and screened for genetic elements associated with arsenite tolerance, Integrative and Conjugative Elements (ICEs), among other. The genomes of three representative strains were compared. Most gentamicin resistant (GR) isolates (32/33) were resistant to arsenite, and harbored ICE- and ars operon-related genes. These genetic elements were not detected in any of the five arsenite susceptible strains, regardless of the GR (n = 1) or gentamicin susceptibility (GS) (n = 4) phenotype. The comparison of the genomes of two GR (one resistant and one susceptible to arsenite) and one GS strains suggested that these phenotypes correspond to three phylogroups, distinguished by presence of some genes only in GR isolates, in addition to point mutations in functional genes. The presence of ICEs and ars operon-related genes suggest that arsenite resistance might have been acquired by GR lineages.
Topics: Anti-Bacterial Agents; Arsenites; Conjugation, Genetic; Drinking Water; Drug Resistance, Multiple, Bacterial; Genome, Bacterial; Gentamicins; Humans; Microbial Sensitivity Tests; Ralstonia pickettii; Wastewater
PubMed: 33197514
DOI: 10.1016/j.resmic.2020.11.001 -
Journal of Personalized Medicine Apr 2021The microbiota has been reported to be correlated with carcinogenesis and cancer progression. However, its involvement in the pathology of mesothelioma remains unknown....
The microbiota has been reported to be correlated with carcinogenesis and cancer progression. However, its involvement in the pathology of mesothelioma remains unknown. In this study, we aimed to identify mesothelioma-specific microbiota using resected or biopsied mesothelioma samples. Eight mesothelioma tissue samples were analyzed via polymerase chain reaction (PCR) amplification and 16S rRNA gene sequencing. The operational taxonomic units (OTUs) of the effective tags were analyzed in order to determine the taxon composition of each sample. For the three patients who underwent extra pleural pneumonectomy, normal peripheral lung tissues adjacent to the tumor were also included, and the same analysis was performed. In total, 61 OTUs were identified in the tumor and lung tissues, which were classified into 36 species. and were identified as abundant species in almost all tumor and lung samples. and were found to comprise mesothelioma-specific microbiota involved in tumor progression; thus, they could serve as targets for the prevention of mesothelioma.
PubMed: 33919754
DOI: 10.3390/jpm11040297 -
Journal of Microbiology, Immunology,... Feb 2022Ralstonia pickettii is an opportunistic waterborne microbe which can survive in many kinds of solutions. Contamination of these solutions may result as outbreaks, which...
BACKGROUND
Ralstonia pickettii is an opportunistic waterborne microbe which can survive in many kinds of solutions. Contamination of these solutions may result as outbreaks, which can be mortal for immuncompromised patients. Herein we report an outbreak of R. pickettii related to contaminated saline infusion in our center.
METHODS
This study was conducted in Ankara Pediatric City Hospital. An outbreak occured in Pediatric Hematology and Oncology Unit between August 28, 2019 and September 13, 2019. When the outbreak occured, infection control team began an investigation. Environmental samples were collected in order to find the source of the outbreak.
RESULTS
A total of 11 patients with catheter related blood stream infection caused by R. pickettii who were diagnosed with leukemia were affected. None of the patients infected with R. pickettii died during the outbreak. A total of seventy environmental samples were cultured with the purpose of finding the source of outbreak. R. pickettii grew in normal saline solution culture and all isolates had the same clone of R. pickettii. The outbreak lasted two weeks and was controlled by stopping the usage and sending back the saline solutions belonging to the same manufacturing batch.
CONCLUSIONS
We reported an outbreak of R. pickettii BSIs in highly immunocompromised patients due to contaminated intravascular solution, which was rapidly controlled by infection control measures. Vigilant surveillance by hospital infection control teams and prompt investigation to identify the source of nosocomial infections are crucial to stop an outbreak.
Topics: Child; Cross Infection; Disease Outbreaks; Humans; Leukemia; Ralstonia pickettii; Sepsis
PubMed: 33461864
DOI: 10.1016/j.jmii.2020.12.004 -
Antonie Van Leeuwenhoek Oct 2021To improve understanding of the role of Ralstonia in cystic fibrosis (CF), whole genomes of 18 strains from clinical samples were sequenced using Illumina technology....
To improve understanding of the role of Ralstonia in cystic fibrosis (CF), whole genomes of 18 strains from clinical samples were sequenced using Illumina technology. Sequences were analysed by core genome Multi-Locus Sequence Typing, Average Nucleotide Identity based on BLAST (ANIb), RAST annotation, and by ResFinder. Phylogenetic analysis was performed for the 16S rRNA gene, and the OXA-22 and OXA-60 ß-lactamase families. The minimal inhibitory concentrations (MICs) were determined using broth microdilution. ANIb data for the 18 isolates and 54 strains from GenBank, supported by phylogenetic analysis, showed that 8 groups of clusters (A-H), as well as subgroups that should be considered as species or subspecies. Groups A-C contain strains previously identified as Ralstonia solanacearum and Ralstonia pseudosolanacearum. We propose that group A is a novel species. Group B and C are Ralstonia syzygii, Ralstonia solanacearum, respectively. Group D is composed of Ralstonia mannitolilytica and Group E of Ralstonia pickettii. Group F and G should be considered novel species. Group H strains belong to R. insidiosa. OXA-22 and OXA-60 family ß-lactamases were encoded by all strains. Co-trimoxazole generally showed high activity with low MICs (≤1 mg/l) as did ciprofloxacin (≤0.12 mg/l). MICs against the other antibiotics were more variable, but generally high. RAST annotation revealed limited differences between the strains, and virulence factors were not identified. The taxonomy of the genus Ralstonia is in need of revision, but sequencing additional isolates is needed. Antibiotic resistance levels are high. Annotation did not identify potential virulence factors.
Topics: Humans; Multilocus Sequence Typing; Phylogeny; RNA, Ribosomal, 16S; Ralstonia
PubMed: 34463860
DOI: 10.1007/s10482-021-01637-0 -
Journal of Applied Microbiology Oct 2007Xenobiotic pollutants such as toluene and trichloroethylene are released into the environment by various industrial processes. Ralstonia pickettii possess significant... (Review)
Review
Xenobiotic pollutants such as toluene and trichloroethylene are released into the environment by various industrial processes. Ralstonia pickettii possess significant biotechnological potential in the field of bioremediation and has demonstrated the ability to breakdown many of these toxic substances. Here, we provide a description of the major compounds that various strains of R. pickettii are capable of degrading and a brief review of their breakdown pathways and an argument for its use in bioremediation.
Topics: Biodegradation, Environmental; Chlorophenols; Environmental Pollutants; Hydrocarbons, Aromatic; Ralstonia pickettii
PubMed: 17897177
DOI: 10.1111/j.1365-2672.2007.03361.x -
Journal of Microbiology and... Sep 2019DDT is a hydrophobic organic pollutant, which can be bio-accumulated in nature and have adverse consequences on the physical condition of humans and animals. This study...
DDT is a hydrophobic organic pollutant, which can be bio-accumulated in nature and have adverse consequences on the physical condition of humans and animals. This study investigated the relationship between the white-rot fungus and biosurfactantproducing bacterium associated with the degradation of DDT. The effects of on fungal development were examined using in vitro confrontation assay on a potato dextrose agar (PDA) medium. culture was added to the culture at 1, 3, 5, 7, and 10 ml (1 ml ≈ 1.44 × 10 CFU). After 7 d incubation, about 43% of the initial DDT (12.5 μM) was degraded by the culture only. The augmentation of 7 ml of culture revealed a more highly optimized synergism with DDT degradation being approximately 78% and the ratio of optimization 1.06. According to the confrontational assay, promoted the growth of towards the bacterial colony, with no direct contact between the bacterial cells and mycelium (0.71 cm/day). DDD (1,1-dichloro-2,2-bis(4- chlorophenyl) ethane), DDE (1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene), and DDMU (1- chloro-2,2-bis(4-chlorophenyl) ethylene) were identified as metabolic products, indicating that the could enhance the DDT biodegradation by .
Topics: Biodegradation, Environmental; Coculture Techniques; DDT; Insecticides; Pleurotus; Ralstonia pickettii
PubMed: 31474097
DOI: 10.4014/jmb.1906.06030 -
Medicine Jul 2019By 2030, the annual number of combined total hip and knee arthroplasty is estimated to reach 3.5 to 4 million in the US alone. In the context of a constant increase of... (Observational Study)
Observational Study
By 2030, the annual number of combined total hip and knee arthroplasty is estimated to reach 3.5 to 4 million in the US alone. In the context of a constant increase of the number of primary and revision total hip and knee arthroplasty, an increased risk of complication is expected. Prosthetic joint infections (PJIs) represent major cause of healthcare expenditure and morbidity. PJI still remain the most common and feared arthroplasty complication. A rapid and correct diagnosis of infection is decisive for a correct therapeutical management. In this setting, the Academic Emergency Hospital Sibiu adopted and implemented, with the beginning of September 2016, a new strategy for the diagnosis of PJIs strategy that uses sonication and beacon-based fluorescent in situ hybridization (bbFISH) technology.Until November 2017, 40 patients (40 retrieved implants) were enrolled in the study. Sonication fluid (SF) was collected after sonication of the implants, and samples were harvested on aerobic and anaerobic culture media. A bbFISH was used as a rapid method of bacteria detection.16 patients were diagnosed with PJIs (all 16 patients presented a positive culture of the SF). Comparing bbFISH with culture, 11 samples tested true-positive. As the kit doesn't contain probes for Pseudomonas fluorescens or Ralstonia pickettii, 4 strains of R pickettii and 1 strain of P fluorescens that was associated with Staphylococcus epidermidis were not detected.Bacteria culture of SF remains the gold standard. bbFISH holds promise to be a diagnostic tool for rapid identifying of PJIs. The bbFISH assay needs to be optimized for the detection of bacterial strains that are relevant for the PJIs field.
Topics: Aged; Aged, 80 and over; Arthroplasty, Replacement, Hip; Arthroplasty, Replacement, Knee; Bacterial Infections; Bacteriological Techniques; Connective Tissue; Female; Humans; In Situ Hybridization, Fluorescence; Male; Middle Aged; Prosthesis-Related Infections; RNA, Bacterial; RNA, Ribosomal, 16S; Sonication; Synovial Fluid
PubMed: 31335719
DOI: 10.1097/MD.0000000000016501 -
Journal of Global Antimicrobial... Jun 2020Ralstonia pickettii has been increasingly recognised as an emerging opportunistic pathogen in hospital settings in recent years, especially in patients with prolonged...
Genotypic and phylogenetic characterisation of a clinical Ralstonia pickettii strain carrying two novel OXA allelic variants, bla and bla, isolated from a bloodstream infection in China.
OBJECTIVES
Ralstonia pickettii has been increasingly recognised as an emerging opportunistic pathogen in hospital settings in recent years, especially in patients with prolonged hospital stay. Clinical manifestations associated with R. pickettii infection range from mild infections to severe invasive life-threatening infections. Here we report the genome sequence of a clinical R. pickettii strain (PSLESD1) carrying two novel bla allelic variants in China.
METHODS
Whole-genome sequencing of strain PSLESD1 was performed using an Illumina NovaSeq 6000 platform. Antimicrobial resistance genes were identified using the BacWGSTdb server. The phylogenetic relationship betweenR. pickettii PSLESD1 and a total of 17 R. pickettii strains deposited in the NCBI GenBank database was analysed using NJ (neighbour joining)/UPGMA (unweighted pair-group method with arithmetic mean) phylogeny (MAFFT v.7) based on core genome single nucleotide polymorphism (SNP) data.
RESULTS
The draft genome sequence of R. pickettii strain PSLESD1 consists of 25 contigs comprising 5 267 333 bp. Three antimicrobial resistance genes were identified in the genome, including bla, bla and sul2. Strain PSLESD1 was resistant to aminoglycosides and carbapenems including meropenem. Phylogenetic analysis showed that all strains retrieved from the NCBI GenBank database were epidemiologically unrelated. The closest relative of strain PSLESD1 was H2Cu2, which differed by 2908 SNPs.
CONCLUSION
In summary, we report the first genome sequence of a clinicalR. pickettii strain harbouring two novel class D β-lactamase genes (bla and bla) recovered from a bloodstream infection in China. These data may help to understand the genomic features and antimicrobial resistance mechanisms of this bacterial pathogen.
Topics: China; Humans; Microbial Sensitivity Tests; Phylogeny; Ralstonia pickettii; Sepsis
PubMed: 32169680
DOI: 10.1016/j.jgar.2020.02.020 -
ISME Communications 2022Phototrophic communities of autotrophic microalgae and heterotrophic bacteria perform complex tasks of nutrient acquisition and tackling environmental stress but remain...
Phototrophic communities of autotrophic microalgae and heterotrophic bacteria perform complex tasks of nutrient acquisition and tackling environmental stress but remain underexplored as a basis for the bioremediation of emerging pollutants. In industrial monoculture designs, poor iron uptake by microalgae limits their productivity and biotechnological efficacy. Iron supplementation is expensive and ineffective because iron remains insoluble in an aqueous medium and is biologically unavailable. However, microalgae develop complex interkingdom associations with siderophore-producing bacteria that help solubilize iron and increase its bioavailability. Using dye degradation as a model, we combined environmental isolations and synthetic ecology as a workflow to design a simplified microbial community based on iron and carbon exchange. We established a mutualism between the previously non-associated alga and siderophore-producing bacterium . Siderophore-mediated increase in iron bioavailability alleviated Fe stress for algae and increased the reductive iron uptake mechanism and bioremediation potential. In exchange, produced galactose, glucose, and mannose as major extracellular monosaccharides, supporting bacterial growth. We propose that extracellular iron reduction by ferrireductase is crucial for azoreductase-mediated dye degradation in microalgae. These results demonstrate that iron bioavailability, often overlooked in cultivation, governs microalgal growth, enzymatic processes, and bioremediation potential. Our results suggest that phototrophic communities with an active association for iron and carbon exchange have the potential to overcome challenges associated with micronutrient availability, while scaling up bioremediation designs.
PubMed: 36407791
DOI: 10.1038/s43705-022-00161-0