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Frontiers in Cellular and Infection... 2023is a multidrug-resistant (MDR) opportunistic pathogen with high resistance to most clinically used antimicrobials. The dissemination of MDR and difficult treatment of...
BACKGROUND
is a multidrug-resistant (MDR) opportunistic pathogen with high resistance to most clinically used antimicrobials. The dissemination of MDR and difficult treatment of its infection in clinical settings are global issues.
METHODS
To provide more genetic information on and find a better treatment strategy, we isolated five , SMYN41-SMYN45, from a Chinese community that were subjected to antibiotic susceptibility testing, biofilm formation assay, and whole-genome sequencing. Whole-genome sequences were compared with other thirty-seven sequences.
RESULTS
The five strains had similar antibiotic resistance profiles and were resistant to β-lactams, aminoglycosides, and macrolides. They showed similar antimicrobial resistance (AMR) genes, including various efflux pumps, β-lactamase resistance genes (), aminoglycoside resistance genes [, ], and macrolide-resistant gene (). Genome sequencing analysis revealed that SMYN41-SMYN45 belonged to sequence type 925 (ST925), ST926, ST926, ST31, and ST928, respectively, and three new STs were identified (ST925, ST926, and ST928).
CONCLUSION
This study provides genetic information by comparing genome sequences of several isolates from a community of various origins, with the aim of optimizing empirical antibiotic medication and contributing to worldwide efforts to tackle antibiotic resistance.
Topics: Humans; Stenotrophomonas maltophilia; Anti-Bacterial Agents; Anti-Infective Agents; Drug Resistance, Microbial; Genomics; Gram-Negative Bacterial Infections; Microbial Sensitivity Tests
PubMed: 38089814
DOI: 10.3389/fcimb.2023.1266295 -
Viruses Dec 2023mainly causes respiratory infections that are associated with a high mortality rate among immunocompromised patients. exhibits a high level of antibiotic resistance...
mainly causes respiratory infections that are associated with a high mortality rate among immunocompromised patients. exhibits a high level of antibiotic resistance and can form biofilms, which complicates the treatment of patients infected with this bacterium. Phages combined with antibiotics could be a promising treatment option. Currently, ~60 phages are known, and their effects on biofilm formation and antibiotic sensitivity require further examination. Bacteriophage StM171, which was isolated from hospital wastewater, showed a medium host range, low burst size, and low lytic activity. StM171 has a 44kbp dsDNA genome that encodes 59 open-reading frames. A comparative genomic analysis indicated that StM171, along with the phage Suso (MZ326866) and phage HXX_Dennis (ON711490), are members of a new putative genus. strains that developed resistance to StM171 (bacterial-insensitive mutants) showed a changed sensitivity to antibiotics compared to the originally susceptible strains. Some bacterial-insensitive mutants restored sensitivity to cephalosporin and penicillin-like antibiotics and became resistant to erythromycin. StM171 shows strain- and antibiotic-dependent effects on the biofilm formation of strains.
Topics: Humans; Anti-Bacterial Agents; Bacteriophages; Stenotrophomonas maltophilia; Biofilms
PubMed: 38140696
DOI: 10.3390/v15122455 -
Clinical Infectious Diseases : An... May 2021
Topics: Carbapenems; Gram-Negative Bacterial Infections; Humans; Laboratories; Leukemia, Myeloid, Acute; Microbiota; Stenotrophomonas maltophilia
PubMed: 32544944
DOI: 10.1093/cid/ciaa766 -
Current Microbiology Nov 2023Stenotrophomonas maltophilia is an opportunistic human pathogen associated with nosocomial and community-acquired infections. We have conducted a microbiological and...
Stenotrophomonas maltophilia is an opportunistic human pathogen associated with nosocomial and community-acquired infections. We have conducted a microbiological and genomic surveillance study of broad-spectrum cephalosporin- and carbapenem-resistant Gram-negative bacteria colonizing wild birds inhabiting the Brazilian Amazonia. Strikingly, two S. maltophilia strains (SM79 and SM115) were identified in Plain-throated antwren (Isleria hauxwelli) passerines affected by Amazonian fragmentation and degradation. Noteworthy, SM79 and SM115 strains belonged to new sequence types (STs) ST474 and ST473, respectively, displaying resistance to broad-spectrum β-lactams, aminoglycosides and/or fluoroquinolones. In this regard, resistome analysis confirmed efflux pumps (smeABC, smeDEF, emrAB-tolC and macB), bla and bla, aph(3')-IIc and aac(6')-Iak, and Smqnr resistance genes. Comparative phylogenomic analysis with publicly available S. maltophilia genomes clustered ST473 and ST474 with human strains, whereas the ST474 was also grouped with S. maltophilia strains isolated from water and poultry samples. In summary, we report two novel sequence types of S. maltophilia colonizing wild Amazonian birds. The presence of opportunistic multidrug-resistant pathogens in wild birds, from remotes areas, could represent an ecological problem since these animals could easily promote long-distance dispersal of medically important antimicrobial-resistant bacteria. Therefore, while our results could provide a baseline for future epidemiological genomic studies, considering the limited information regarding S. maltophilia circulating among wild animals, additional studies are necessary to evaluate the clinical impact and degree of pathogenicity of this human opportunistic pathogen in wild birds.
Topics: Humans; Animals; Stenotrophomonas maltophilia; Brazil; Animals, Wild; Microbial Sensitivity Tests; Anti-Bacterial Agents; Gram-Negative Bacterial Infections
PubMed: 38008776
DOI: 10.1007/s00284-023-03532-5 -
Current Microbiology May 2022Stenotrophomonas maltophilia is an environmental bacterium that has gained a lot of attention, as a nosocomial pathogen associated with significant mortality rates....
Stenotrophomonas maltophilia is an environmental bacterium that has gained a lot of attention, as a nosocomial pathogen associated with significant mortality rates. Biofilm formation is considered the corner stone for establishing infections in many bacteria including S. maltophilia. The aim of this study was the genotypic characterization of the different virulence-associated genes and the investigation of the effect of ascorbic acid on S. maltophilia biofilm formation. A total of 20 S. maltophilia isolates from different sources were included in this study. Genes encoding different virulence factors were investigated genotypically. These included stmPr1, stmPr2, smlt3773 locus, smf-1, rpfF, rmlA and spgM. Biofilm formation was investigated phenotypically. The effect of ascorbic acid on biofilm formation was investigated using MIC as well as sub-inhibitory concentrations. Many of the isolates harbored both serine proteases genes stmPr-1 and stmPr-2. Fourteen (70%) of the 20 isolates carried stmPr-1 and 15 (75%) had stmPr-2. Most of the isolates (95%) possessed smlt-3773 locus. Genes linked to biofilm formation such as smf-1, rpfF, rmlA and spgM, were found in (90%), (45%), (85%) and (30%) of the isolates, respectively. Phenotypically, all S. maltophilia isolates (100%) were biofilm producers. Fifteen (75%) were strong biofilm producers and 5 (25%) were moderate biofilm producers. In attempts to seek a non-chemotherapeutic alternative that can hinder biofilm formation without provoking antimicrobial resistance, the results, herein, showed that ascorbic acid inhibits biofilm formation in a dose-dependent manner.
Topics: Ascorbic Acid; Biofilms; Gram-Negative Bacterial Infections; Humans; Stenotrophomonas maltophilia; Virulence
PubMed: 35508743
DOI: 10.1007/s00284-022-02869-7 -
Saudi Journal of Biological Sciences Nov 2019The bacterium with an ability to produce extracellular fibrinolytic protease was isolated and identified as Gd2 based on ribotyping. The fibrinolytic profile of this...
The bacterium with an ability to produce extracellular fibrinolytic protease was isolated and identified as Gd2 based on ribotyping. The fibrinolytic profile of this enzyme depicted 73% of fibrin clot dissolution within 4 h. Fibrinolytic enzyme yield influenced by different physiological (incubation time, temperature, agitation and pH), nutritional (macronutrients such as carbon and nitrogen sources) and biological (inoculums age and inoculums concentration) parameters of fermentation which were optimized based on one-factor-at-a-time (OFAT) approach. The enzyme yield improved from 886 to 1795 FU ml upon OFAT; optimized conditions include temperature - 33 °C, pH - 8.0, incubation time - 36 h, agitation - 150 RPM, 3% v/v inoculums and age of inoculum - 18 h. Further optimization of enzyme production was achieved with implementation of Plackett-Burman media designing where the production levels increased to 3411 FU ml and noticed that peptone, pH, dextrose and KHPO was found to be significant factor. This ms reports the highest fibrinolytic enzyme yield with to that of literature reports.
PubMed: 31762628
DOI: 10.1016/j.sjbs.2018.10.014 -
The Journal of the Royal College of... Mar 2022causes opportunistic respiratory infections and is associated with declining lung function in patients with cystic fibrosis (CF). Risk factors for carrying remain...
BACKGROUND
causes opportunistic respiratory infections and is associated with declining lung function in patients with cystic fibrosis (CF). Risk factors for carrying remain unclear.
METHODS
We conducted a retrospective study of patients yielding ⩾1 respiratory isolate at the Oxford University Hospitals Trust between 2014 and 2019 and a cohort study of carriage in CF patients attending annual review in 2018.
RESULTS
Seven hundred and forty isolates were identified from 238 patients (median 1.0 isolate/patient). Predisposing conditions included invasive ventilation (29.8%), CF (25.6%) and non-CF bronchiectasis (24.4%). The rates of isolates and co-trimoxazole resistance were stable over time. About 10.8% of isolates were co-trimoxazole-resistant, with resistance more common in CF than in other diagnoses (29.5% vs 5.8%, < 0.001). No clinical features were significantly associated with carriage in the CF population.
DISCUSSION
We present new insight into the epidemiology of colonisation/infection and identify increased co-trimoxazole resistance in CF isolates.
Topics: Anti-Bacterial Agents; Cohort Studies; Cystic Fibrosis; Gram-Negative Bacterial Infections; Humans; Lung; Retrospective Studies; Stenotrophomonas maltophilia; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 36146962
DOI: 10.1177/14782715221088909 -
Preparative Biochemistry & Biotechnology 2023This study aimed to determine the ability of bacteria to produce the chitinase enzyme, purify, and characterize the enzyme from the isolate with the best activity, and...
This study aimed to determine the ability of bacteria to produce the chitinase enzyme, purify, and characterize the enzyme from the isolate with the best activity, and determine the use of this purified enzyme as a biocontrol agent. The chitinolytic bacterium was identified as . The chitinase enzyme was purified 1.4 times at a 30% ammonium sulfate concentration with a yield of 40.7%. Following partial purification, the enzyme was purified by ion-exchange chromatography using HiPrep Q XL 16/10 column and HiPrep™ 26/10 desalting column with 25.34% and 18.12% yields, respectively. It was calculated that the purified enzyme had a molecular weight of 52 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimum activity of the enzyme was determined at 50 °C and pH 7.0. Enzyme activity was most induced by Fe, while it was most inhibited by Zn at 5 mM concentration. and values of the enzyme for colloidal chitin were calculated as 1.6419 mg/mL and 16.129 U/mg, respectively. The purified chitinase was used as a biocontrol agent against the fungus and potato beetle . The enzyme was shown to be effective in reducing the growth of fungus and causing disruption of the chitin structure of potato beetle.
Topics: Antifungal Agents; Stenotrophomonas maltophilia; Chitinases; Fungi; Chitin; Hydrogen-Ion Concentration; Temperature
PubMed: 36369794
DOI: 10.1080/10826068.2022.2142942 -
The Journal of Infection Mar 2020Stenotrophomonas maltophilia (SM) is increasingly identified in intensive care unit (ICU). This study aim to identify risk factors for SM ventilator-associated pneumonia...
BACKGROUND
Stenotrophomonas maltophilia (SM) is increasingly identified in intensive care unit (ICU). This study aim to identify risk factors for SM ventilator-associated pneumonia (VAP) and whether it affects ICU mortality METHODS: Two nested matched case-control studies were performed based in OUTCOMEREA database. The first episodes of SM-VAP patients were matched with two different control groups: VAP due to other micro-organisms (VAP-other) and Pseudomonas aeruginosa VAP (Pyo-VAP). Matching criteria were the hospital, the SAPS II, and the previous duration of mechanical ventilation (MV).
RESULTS
Of the 102 SM-VAP patients (6.2% of all VAP patients), 92 were matched with 375 controls for the SM-VAP/other-VAP matching and 84 with 237 controls for the SM-VAP/Pyo-VAP matching. SM-VAP risk factors were an exposition to ureido/carboxypenicillin or carbapenem during the week before VAP, and respiratory and coagulation components of SOFA score upper to 2 before VAP. SM-VAP received early adequate therapy in 70 cases (68.6%). Risk factors for Day-30 were age (OR = 1.03; p < 0.01) and Chronic heart failure (OR = 3.15; p < 0.01). Adequate treatment, either monotherapy or combination of antimicrobials, did not modify mortality. There was no difference in 30-day mortality, but 60-day mortality was higher in patients with SM-VAP compared to Other-VAP (P = 0.056).
CONCLUSIONS
In a large series, independent risk factors for the SM-VAP were ureido/carboxypenicillin or carbapenem exposure the week before VAP, and respiratory and coagulation components of the SOFA score > 2 before VAP. Mortality risk factors of SM-VAP were age and chronic heart failure. Adequate treatment did not improve SM-VAP prognosis.
Topics: Carbapenems; Humans; Intensive Care Units; Pneumonia, Ventilator-Associated; Risk Factors; Stenotrophomonas maltophilia
PubMed: 31682878
DOI: 10.1016/j.jinf.2019.10.021 -
The American Journal of Case Reports Jul 2022BACKGROUND We aimed to identify the risk factors for Stenotrophomonas maltophilia infection in patients with COVID-19. CASE REPORT Case 1. A 52-year-old... (Review)
Review
BACKGROUND We aimed to identify the risk factors for Stenotrophomonas maltophilia infection in patients with COVID-19. CASE REPORT Case 1. A 52-year-old COVID-19-positive woman with systemic lupus erythematosus was administered remdesivir (RDV) and methylprednisolone (mPSL) 1000 mg/day for 3 days, and subsequently administered baricitinib and ceftriaxone. Following respiratory deterioration, she was transferred to the Intensive Care Unit (ICU) and the antibiotics were switched to meropenem (MEPM). Blood and sputum cultures were positive for S. maltophilia. Administration of trimethoprim-sulfamethoxazole (TMP-SMX) showed clinical improvement. Case 2. An 80-year-old COVID-19-positive man was treated with RDV, dexamethasone, and baricitinib. Owing to severe hypoxia, he was transferred to the ICU and MEPM was administered. Sputum culture was positive for S. maltophilia. TMP-SMX administration temporarily improved his symptoms; however, he died from COVID-19-associated invasive aspergillosis. Case 3. A 48-year-old COVID-19-positive man who was mechanically intubated was transferred to our hospital and treated with RDV, mPSL, and piperacillin/tazobactam. Sputum culture revealed S. maltophilia; treatment with TMP-SMX improved his respiratory status. Case 4. An 80-year-old COVID-19-positive man was treated with RDV and dexamethasone. Owing to severe hypoxemia, he was transferred to the ICU and the antibiotics were switched to MEPM. Sputum culture revealed S. maltophilia. Administration of TMX-SMX improved his respiratory status. CONCLUSIONS Isolation of S. maltophilia in respiratory specimens of patients with COVID-19 should prompt clinicians to administer treatment for S. maltophilia-associated pneumonia in ICU-admitted patients who have been intubated, have been administered broad-spectrum antibiotics, or have immunocompromised status.
Topics: Aged, 80 and over; Anti-Bacterial Agents; COVID-19; Dexamethasone; Female; Gram-Negative Bacterial Infections; Humans; Male; Middle Aged; Stenotrophomonas maltophilia; Trimethoprim, Sulfamethoxazole Drug Combination
PubMed: 35852985
DOI: 10.12659/AJCR.936889