-
Journal of Medical Case Reports Mar 2024Stenotrophomonas maltophilia is a gram-negative bacteria known for causing opportunistic and nosocomial infections in humans. S. maltophilia is an emerging pathogen of...
BACKGROUND
Stenotrophomonas maltophilia is a gram-negative bacteria known for causing opportunistic and nosocomial infections in humans. S. maltophilia is an emerging pathogen of concern due to it's increasing prevalence, diverse disease spectrum, intrinsic multi-drug resistance and high mortality rates in immunocompromised individuals. S. maltophilia is a rare cause of neonatal sepsis associated with significant morbidity and mortality. The bacterium's multi-drug resistance poses a considerable challenge for treatment, with various mechanisms contributing to its resistance.
CASE PRESENTATION
We report a case involving a 40-h-old male African neonate who exhibited symptoms of neonatal sepsis. The blood culture revealed Stenotrophomonas maltophilia, which was sensitive to ciprofloxacin and gentamicin but resistant to other antibiotics. Lumbar puncture for CSF could not be done because the father declined. We treated the newborn with the empirical first-line antibiotics as per the national guideline intravenous ampicillin and gentamicin for six days, and the child recovered fully with a repeated negative blood culture.
CONCLUSIONS
This report describes a neonatal sepsis case caused by S. maltophilia, a multi-drug resistant bacteria and a rare cause of neonatal sepsis. We report that early detection of the bacterial and antimicrobial management based on local antibiogram data may be essential for successful patient's management.
Topics: Child; Infant, Newborn; Male; Humans; Stenotrophomonas maltophilia; Neonatal Sepsis; Gram-Negative Bacterial Infections; Anti-Bacterial Agents; Gentamicins
PubMed: 38523318
DOI: 10.1186/s13256-024-04479-2 -
Annals of Clinical Microbiology and... Mar 2024Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge.
AIM
The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies.
METHOD
A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis.
RESULT
Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010.
CONCLUSIONS
Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.
Topics: Humans; Trimethoprim, Sulfamethoxazole Drug Combination; Minocycline; Stenotrophomonas maltophilia; Microbial Sensitivity Tests; Anti-Bacterial Agents; Cefiderocol; Drug Resistance, Microbial; Gram-Negative Bacterial Infections
PubMed: 38504262
DOI: 10.1186/s12941-024-00685-4 -
Frontiers in Plant Science 2024Microbial biofertilizers or biocontrol agents are potential sustainable approaches to overcome the limitations of conventional agricultural practice. However, the...
INTRODUCTION
Microbial biofertilizers or biocontrol agents are potential sustainable approaches to overcome the limitations of conventional agricultural practice. However, the limited catalog of microbial candidates for diversified crops creates hurdles in successfully implementing sustainable agriculture for increasing global/local populations. The present study aimed to explore the wheat rhizosphere microbiota for microbial strains with a biofertilizer and biocontrol potential.
METHODS
Using a microbial culturing-based approach, 12 unique microbial isolates were identified and screened for biofertilizer/biocontrol potential using genomics and physiological experimentations.
RESULTS AND DISCUSSION
Molecular, physiological, and phylogenetic characterization identified BCM as a potential microbial candidate for sustainable agriculture. BCM was identified as a coccus-shaped gram-negative microbe having optimal growth at 37°C in a partially alkaline environment (pH 8.0) with a proliferation time of ~67 minutes. The stress response physiology of BCM indicates its successful survival in dynamic environmental conditions. It significantly increased (P <0.05) the wheat seed germination percentage in the presence of phytopathogens and saline conditions. Genomic characterization decoded the presence of genes involved in plant growth promotion, nutrient assimilation, and antimicrobial activity. Experimental evidence also correlates with genomic insights to explain the potential of BCM as a potential biofertilizer and biocontrol agent. With these properties, BCM could sustainably promote wheat production to ensure food security for the increasing population, especially in native wheat-consuming areas.
PubMed: 38501138
DOI: 10.3389/fpls.2024.1364807 -
Frontiers in Cellular and Infection... 2024are ubiquitous Gram-negative bacteria found in both natural and clinical environments. It is a remarkably adaptable species capable of thriving in various environments,...
are ubiquitous Gram-negative bacteria found in both natural and clinical environments. It is a remarkably adaptable species capable of thriving in various environments, thanks to the plasticity of its genome and a diverse array of genes that encode a wide range of functions. Among these functions, one notable trait is its remarkable ability to resist various antimicrobial agents, primarily through mechanisms that regulate the diffusion across cell membranes. We have investigated the Mla ABC transport system of , which in other Gram-negative bacteria is known to transport phospholipids across the periplasm and is involved in maintaining outer membrane homeostasis. First, we structurally and functionally characterized the periplasmic substrate-binding protein MlaC, which determines the specificity of this system. The predicted structure of the MlaC protein revealed a hydrophobic cavity of sufficient size to accommodate the phospholipids commonly found in this species. Moreover, recombinant MlaC produced heterologously demonstrated the ability to bind phospholipids. Gene knockout experiments in K279a revealed that the Mla system is involved in baseline resistance to antimicrobial and antibiofilm agents, especially those with divalent-cation chelating activity. Co-culture experiments with also showed a significant contribution of this system to the cooperation between both species in the formation of polymicrobial biofilms. As suggested for other Gram-negative pathogenic microorganisms, this system emerges as an appealing target for potential combined antimicrobial therapies.
Topics: Humans; Stenotrophomonas maltophilia; Gram-Negative Bacteria; Biofilms; Cell Membrane; Anti-Infective Agents; Gram-Negative Bacterial Infections
PubMed: 38469346
DOI: 10.3389/fcimb.2024.1346565 -
Cureus Feb 2024Surgically induced necrotizing scleritis (SINS) is a rare inflammatory disease of the sclera that occurs following ocular surgery, specifically pterygium surgery and...
Surgically induced necrotizing scleritis (SINS) is a rare inflammatory disease of the sclera that occurs following ocular surgery, specifically pterygium surgery and scleral buckling. Here, we report a case of SINS in a 78-year-old female patient after segmental scleral buckling for rhegmatogenous retinal detachment. The retina was restored after scleral buckling, and the postoperative course was uneventful. However, the patient developed ocular discharge and conjunctival hyperemia, indicating infection, after two months. The sclera became thinner and intraocular inflammation developed after buckle removal. was isolated from the ocular discharge, and the patient was treated with antibacterial agents susceptible to the bacteria. However, her symptoms persisted, and corrected visual acuity decreased from 20/25 to 20/1000. Oral steroid treatment was initiated because of the suspicion of SINS. Intraocular inflammation gradually subsided, the thin sclera was covered by conjunctival tissue, and the patient's corrected visual acuity improved to 20/32, which stabilized her condition. Infection with after scleral buckling is extremely rare, and SINS development in such cases is unprecedented.
PubMed: 38465044
DOI: 10.7759/cureus.53876 -
BMC Microbiology Mar 2024Copper-induced gene expression in Xanthomonas campestris pv. campestris (Xcc) is typically evaluated using targeted approaches involving qPCR. The global response to...
BACKGROUND
Copper-induced gene expression in Xanthomonas campestris pv. campestris (Xcc) is typically evaluated using targeted approaches involving qPCR. The global response to copper stress in Xcc and resistance to metal induced damage is not well understood. However, homologs of heavy metal efflux genes from the related Stenotrophomonas genus are found in Xanthomonas which suggests that metal related efflux may also be present.
METHODS AND RESULTS
Gene expression in Xcc strain BrA1 exposed to 0.8 mM CuSO.5HO for 15 minutes was captured using RNA-seq analysis. Changes in expression was noted for genes related to general stress responses and oxidoreductases, biofilm formation, protein folding chaperones, heat-shock proteins, membrane lipid profile, multiple drug and efflux (MDR) transporters, and DNA repair were documented. At this timepoint only the cohL (copper homeostasis/tolerance) gene was upregulated as well as a chromosomal czcCBA efflux operon. An additional screen up to 4 hrs using qPCR was conducted using a wider range of heavy metals. Target genes included a cop-containing heavy metal resistance island and putative metal efflux genes. Several efflux pumps, including a copper resistance associated homolog from S. maltophilia, were upregulated under toxic copper stress. However, these pumps were also upregulated in response to other toxic heavy metals. Additionally, the temporal expression of the coh and cop operons was also observed, demonstrating co-expression of tolerance responses and later activation of part of the cop operon.
CONCLUSIONS
Overall, initial transcriptional responses focused on combating oxidative stress, mitigating protein damage and potentially increasing resistance to heavy metals and other biocides. A putative copper responsive efflux gene and others which might play a role in broader heavy metal resistance were also identified. Furthermore, the expression patterns of the cop operon in conjunction with other copper responsive genes allowed for a better understanding of the fate of copper ions in Xanthomonas. This work provides useful evidence for further evaluating MDR and other efflux pumps in metal-specific homeostasis and tolerance phenotypes in the Xanthomonas genus. Furthermore, non-canonical copper tolerance and resistance efflux pumps were potentially identified. These findings have implications for interpreting MIC differences among strains with homologous copLAB resistance genes, understanding survival under copper stress, and resistance in disease management.
Topics: Copper; Xanthomonas campestris; Xanthomonas; Bacterial Proteins
PubMed: 38461228
DOI: 10.1186/s12866-024-03206-7 -
BMJ Open Respiratory Research Mar 2024Inhaled corticosteroids (ICS) are widely used in patients with chronic obstructive pulmonary disease (COPD). However, ICS are associated with an increased risk of... (Observational Study)
Observational Study
OBJECTIVES
Inhaled corticosteroids (ICS) are widely used in patients with chronic obstructive pulmonary disease (COPD). However, ICS are associated with an increased risk of adverse effects.We aimed to determine whether an association between a lower respiratory tract culture with and increasing ICS dosing in patients with COPD exists.
DESIGN
An observational cohort study of outpatients with COPD in Denmark between 2010 and 2018.ICS exposure was categorised into four groups based on average daily consumption 1 year prior to inclusion: no use, low ICS dose (≤400 µg), moderate ICS dose (400-800 µg) and high ICS dose (>800 µg). Dose-response relationship was investigated by a multivariable Cox proportional hazards regression.
RESULTS
Of the total 22 689 patients, 459 had lower respiratory tract cultures positive for . The HR of increased with increasing daily ICS dose: low ICS dose HR 2.6 (95% CI 1.6 to 4.0), moderate ICS dose HR 3.0 (95% CI 1.9 to 4.6) and high ICS dose HR 5.7 (95% CI 3.8 to 8.5).
CONCLUSIONS
We found that ICS was associated with a high, dose-dependent increased hazard of in outpatients with COPD. High dose users had a nearly six times increased hazard compared with non-users of ICS. When appropriate, attempts at de-escalating ICS treatment should be made.
Topics: Humans; Stenotrophomonas maltophilia; Retrospective Studies; Outpatients; Administration, Inhalation; Pulmonary Disease, Chronic Obstructive; Adrenal Cortex Hormones; Cohort Studies
PubMed: 38460975
DOI: 10.1136/bmjresp-2023-001929 -
Annals of Hematology May 2024Stenotrophomonas maltophilia (SM) bloodstream infections (BSIs) contribute to significant mortality in hematologic malignancy (HM) and hematopoietic stem cell...
Stenotrophomonas maltophilia (SM) bloodstream infections (BSIs) contribute to significant mortality in hematologic malignancy (HM) and hematopoietic stem cell transplantation (HSCT) patients. A risk score to predict SM BSI could reduce time to appropriate antimicrobial therapy (TTAT) and improve patient outcomes. A single center cohort study of hospitalized adults with HM/HSCT was conducted. Patients had ≥ 1 blood culture with a Gram-negative (GN) organism. A StenoSCORE was calculated for each patient. The StenoSCORE2 was developed using risk factors for SM BSI identified via logistic regression. Receiver operating characteristic (ROC) curves were plotted. Sensitivity and specificity for the StenoSCORE and StenoSCORE2 were calculated. Thirty-six SM patients and 534 non-SM patients were assessed. A StenoSCORE ≥ 33 points was 80% sensitive, 68% specific, and accurately classified 69% of GN BSIs. StenoSCORE2 variables included acute leukemia, prolonged neutropenia, mucositis, ICU admission, recent meropenem and/or cefepime exposure. The StenoSCORE2 performed better than the StenoSCORE (ROC AUC 0.84 vs. 0.77). A StenoSCORE2 ≥ 4 points was 86% sensitive, 76% specific, and accurately classified 77% of GN BSIs. TTAT was significantly longer for patients with SM BSI compared with non-SM BSI (45.16 h vs. 0.57 h; p < 0.0001). In-hospital and 28-day mortality were significantly higher for patients with SM BSI compared to non-SM BSI (58.3% vs. 18.5% and 66.7% vs. 26.4%; p-value < 0.0001). The StenoSCORE and StenoSCORE2 performed well in predicting SM BSIs in patients with HM/HSCT and GN BSI. Clinical studies evaluating whether StenoSCORE and/or StenoSCORE2 implementation improves TTAT and clinical outcomes are warranted.
Topics: Adult; Humans; Stenotrophomonas maltophilia; Cohort Studies; Bacteremia; Hematologic Neoplasms; Sepsis; Retrospective Studies; Risk Factors; Gram-Negative Bacterial Infections
PubMed: 38453704
DOI: 10.1007/s00277-024-05686-z -
European Journal of Microbiology &... May 2024Extensive use of carbapenems may lead to selection pressure for Stenotrophomonas maltophilia (SM) in hospital environments. The aim of our study was to assess the...
Extensive use of carbapenems may lead to selection pressure for Stenotrophomonas maltophilia (SM) in hospital environments. The aim of our study was to assess the possible association between systemic antibiotic use and the incidence of SM. A retrospective, observational study was carried out in a tertiary-care hospital in Hungary, between January 1st 2010 and December 31st 2019. Incidence-density for SM and SM resistant to trimethoprim-sulfamethoxazole (SXT) was standardized for 1000 patient-days, while systemic antibiotic use was expressed as defined daily doses (DDDs) per 100 patient-days. Mean incidence density for SM infections was 0.42/1000 patient-days; 11.08% were were resistant to SXT, the mean incidence density for SXT-resistant SM was 0.047/1000 patient-days. Consumption rate for colistin, glycopeptides and carbapenems increased by 258.82, 278.94 and 372.72% from 2010 to 2019, respectively. Strong and significant positive correlations were observed with the consumption of carbapenems (r: 0.8759; P < 0.001 and r: 0.8968; P < 0.001), SXT (r: 0.7552; P = 0.011 and r: 0.7004; P = 0.024), and glycopeptides (r: 0.7542; P = 0.012 and r: 0.8138; P < 0.001) with SM and SXT-resistant SM incidence-density/1000 patient-days, respectively. Implementation of institutional carbapenem-sparing strategies are critical in preserving these life-saving drugs, and may affect the microbial spectrum of infections in clinical settings.
PubMed: 38441614
DOI: 10.1556/1886.2024.00022 -
International Journal of Biological... Apr 2024Infections caused by multidrug-resistant pathogens are one of the biggest challenges facing the healthcare system today. Quorum quenching (QQ) enzymes have the potential...
Infections caused by multidrug-resistant pathogens are one of the biggest challenges facing the healthcare system today. Quorum quenching (QQ) enzymes have the potential to be used as innovative enzyme-based antivirulence therapeutics to combat infections caused by multidrug-resistant pathogens. The main objective of this research was to describe the novel YtnP lactonase derived from the clinical isolate Stenotrophomonas maltophilia and to investigate its antivirulence potential against multidrug-resistant Pseudomonas aeruginosa MMA83. YtnP lactonase, the QQ enzyme, belongs to the family of metallo-β-lactamases. The recombinant enzyme has several advantageous biotechnological properties, such as high thermostability, activity in a wide pH range, and no cytotoxic effect. High-performance liquid chromatography analysis revealed the activity of recombinant YtnP lactonase toward a wide range of N-acyl-homoserine lactones (AHLs), quorum sensing signaling molecules, with a higher preference for long-chain AHLs. Recombinant YtnP lactonase was shown to inhibit P. aeruginosa MMA83 biofilm formation, induce biofilm decomposition, and reduce extracellular virulence factors production. Moreover, the lifespan of MMA83-infected Caenorhabditis elegans was prolonged with YtnP lactonase treatment. YtnP lactonase showed synergistic inhibitory activity in combination with gentamicin and acted additively with meropenem against MMA83. The described properties make YtnP lactonase a promising therapeutic candidate for the development of next-generation antivirulence agents.
Topics: Virulence; Pseudomonas aeruginosa; Stenotrophomonas maltophilia; Virulence Factors; Quorum Sensing; Acyl-Butyrolactones; Carboxylic Ester Hydrolases
PubMed: 38423425
DOI: 10.1016/j.ijbiomac.2024.130421