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Revista Espanola de Quimioterapia :... Nov 2023In recent years, new antimicrobials have been introduced in therapeutics, including new beta-lactam-beta-lactamase inhibitor combinations and cefiderocol in response to... (Review)
Review
In recent years, new antimicrobials have been introduced in therapeutics, including new beta-lactam-beta-lactamase inhibitor combinations and cefiderocol in response to therapeutic needs in the face of increasing resistance. There are also different treatment guidelines for infections caused by these microorganisms that have been approved by different professional societies, including those of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), the Infectious Disease Society of America (IDSA) and the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). All of them are based on scientific evidence, but with differences in the weight of expert opinion in their recommendations. Both ESCMID and IDSA include recommendations for the treatment of extended-spectrum beta-lactamase-producing microorganisms. The IDSA is the only one including AmpC producers, all address the treatment of infections caused by carbapenem-resistant Enterobacterales and Acinetobacter baumannii and multidrug-resistant or difficult-to-treat Pseudomonas aeruginosa, and the IDSA and SEIMC include recommendations on the treatment of Stenotrophomonas maltophilia. Future guidelines should integrate new antimicrobials and new innovative management options not covered by current guidelines.
Topics: Humans; Anti-Bacterial Agents; Drug Resistance, Multiple, Bacterial; Cephalosporins; Carbapenems; beta-Lactamase Inhibitors; Communicable Diseases; Gram-Negative Bacteria; Microbial Sensitivity Tests
PubMed: 37997871
DOI: 10.37201/req/s01.11.2023 -
Journal of Ophthalmic Inflammation and... Oct 2023Endophthalmitis is among the most sight-threatening infections in ophthalmology practice. Many microorganisms causing endophthalmitis have been reported....
Endophthalmitis is among the most sight-threatening infections in ophthalmology practice. Many microorganisms causing endophthalmitis have been reported. Stenotrophomonas maltophilia is among the rare causes of endophthalmitis and has been reported after cataract surgery, intravitreal injections and ocular trauma. We report a case of S. maltophilia endophthalmitis after keratoplasty, which is a rare entity, in a 63-year-old female patient.
PubMed: 37831202
DOI: 10.1186/s12348-023-00368-9 -
Frontiers in Microbiology 2024is an opportunistic pathogen intrinsically resistant to multiple and broad-spectrum antibiotics. Although the bacterium is considered a low-virulence pathogen, it can... (Review)
Review
is an opportunistic pathogen intrinsically resistant to multiple and broad-spectrum antibiotics. Although the bacterium is considered a low-virulence pathogen, it can cause various severe diseases and contributes significantly to the pathogenesis of multibacterial infections. During the COVID-19 pandemic, has been recognized as one of the most common causative agents of respiratory co-infections and bacteremia in critically ill COVID-19 patients. The high ability to adapt to unfavorable environments and new habitat niches, as well as the sophisticated switching of metabolic pathways, are unique mechanisms that attract the attention of clinical researchers and experts studying the fundamental basis of virulence. In this review, we have summarized the current knowledge on the molecular aspects of virulence and putative virulence factors, partially touched on interspecific bacterial interactions and iron uptake systems in the context of virulence, and have not addressed antibiotic resistance.
PubMed: 38741741
DOI: 10.3389/fmicb.2024.1385631 -
Microbiology Spectrum Aug 2023Tuberculosis (TB) is an important infectious disease suffered by many countries, including China. In this stage, accurate diagnosis and treatment are key measures for...
Tuberculosis (TB) is an important infectious disease suffered by many countries, including China. In this stage, accurate diagnosis and treatment are key measures for the prevention and control of TB. Stenotrophomonas maltophilia is a global emerging Gram-negative, multidrug-resistant (MDR) organism characterized by its high contribution to the increase in crude mortality rates. By single cell preparation and strain identification, we isolated S. maltophilia from stored cultures of Mycobacterium tuberculosis (Mtb). We found that S. maltophilia could not be removed from sputum by alkali treatment or inhibited by antibiotic mixture added to MGIT 960 indicator tubes. When co-cultured with Mtb on a Löwenstein-Jensen (L-J) slant, it could inhibit the growth of Mtb and liquefy the medium. More seriously, it was resistant to 10 of the 12 anti-TB drugs, including isoniazid and rifampin, and made the mixed samples display multidrug-resistant Mtb (MDR-TB) results in the drug sensitivity test, which might change a treatment regimen and increase disease burden. Following, we conducted a small-scale surveillance which showed that the isolation rate of S. maltophilia in TB patients was 6.74%, but these patients had no special characteristics and the presence of S. maltophilia was hidden. The effect of on TB and its mechanism are unclear and require more attention. China is a high-burden country for tuberculosis (TB), multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB), and HIV-associated TB. Increasing the positive rate of culture and the accuracy of antibiotic susceptibility testing (AST) are important for diagnosis, treatment, and control of TB. In our study, we found that the isolation rate of Stenotrophomonas maltophilia in TB patients was not neglectable and that this bacterium affects the isolation and AST results of TB. Due to a lack of relevant research, the impact of S. maltophilia on the course and outcome of TB is unclear. However, the characteristics of S. maltophilia that increase disease mortality require attention. Therefore, in the clinical testing of TB, in addition to mycobacteria, it is recommended to increase the detection of co-infected bacteria and improve the awareness of TB clinicians of these bacteria.
Topics: Humans; Stenotrophomonas maltophilia; Antitubercular Agents; Tuberculosis; Mycobacterium tuberculosis; Rifampin; Tuberculosis, Multidrug-Resistant; Microbial Sensitivity Tests
PubMed: 37306591
DOI: 10.1128/spectrum.00944-23 -
Microbiology Spectrum Aug 2023Stenotrophomonas maltophilia is increasingly recognized as an important nosocomial pathogen among the Gram-negative bacteria. Intrinsic resistance to different classes...
Stenotrophomonas maltophilia is increasingly recognized as an important nosocomial pathogen among the Gram-negative bacteria. Intrinsic resistance to different classes of antibiotics makes treatment of infections challenging. A deeper understanding of S. maltophilia physiology and virulence requires molecular genetic tools. Here, we describe the implementation of tetracycline-dependent gene regulation ( regulation) in this bacterium. The exploited regulatory sequence of transposon Tn contained the gene and three intertwined promoters, one of which was required for regulated expression of a target gene or operon. The episomal architecture was tested with a variant as a quantifiable reporter. Fluorescence intensity was directly correlated with the concentration of the inducer anhydrotetracycline (ATc) applied and the duration of induction. Also, the expression of the operon of S. maltophilia K279a was subjected to control. These genes code for the synthesis of dTDP-l-rhamnose, an activated nucleotide sugar precursor of lipopolysaccharide (LPS) formation. A Δ mutant was complemented with a plasmid carrying this operon downstream of the sequence. In the presence of ATc, the LPS pattern was similar to that of wild-type S. maltophilia, whereas without the inducer, fewer and apparently shorter O-antigen chains were detected. This underscores the functionality and usefulness of the system for gene regulation and, prospectively, the validation of targets for new anti-S. maltophilia drugs. Stenotrophomonas maltophilia is an emerging pathogen in hospital settings and poses a threat to immunocompromised patients. Due to a high level of resistance to different types of antibiotics, treatment options are limited. We here adapted a tool for inducible expression of genes of interest, known as the system, to S. maltophilia. Genes relevant to producing surface carbohydrate structures (lipopolysaccharide [LPS]) were placed under the control of the system. In the presence of an inducer, the LPS pattern was similar to that of wild-type S. maltophilia, whereas in the "off" state of the system (without inducer), fewer and apparently shorter versions of LPS were detected. The system is functional in S. maltophilia and may be helpful to reveal gene-function relationships to gain a deeper understanding of the bacterium's physiology and virulence.
Topics: Humans; Stenotrophomonas maltophilia; Lipopolysaccharides; Anti-Bacterial Agents; Gene Expression
PubMed: 37378537
DOI: 10.1128/spectrum.01576-23 -
Acta Crystallographica. Section F,... Jul 2023The resistance of the emerging human pathogen Stenotrophomonas maltophilia to tetracycline antibiotics mainly depends on multidrug efflux pumps and ribosomal protection...
The resistance of the emerging human pathogen Stenotrophomonas maltophilia to tetracycline antibiotics mainly depends on multidrug efflux pumps and ribosomal protection enzymes. However, the genomes of several strains of this Gram-negative bacterium code for a FAD-dependent monooxygenase (SmTetX) homologous to tetracycline destructases. This protein was recombinantly produced and its structure and function were investigated. Activity assays using SmTetX showed its ability to modify oxytetracycline with a catalytic rate comparable to those of other destructases. SmTetX shares its fold with the tetracycline destructase TetX from Bacteroides thetaiotaomicron; however, its active site possesses an aromatic region that is unique in this enzyme family. A docking study confirmed tetracycline and its analogues to be the preferred binders amongst various classes of antibiotics.
Topics: Humans; Stenotrophomonas maltophilia; Crystallography, X-Ray; Anti-Bacterial Agents; Tetracycline; Oxytetracycline; Microbial Sensitivity Tests
PubMed: 37405486
DOI: 10.1107/S2053230X23005381 -
European Journal of Clinical... Nov 2023To summarize the current knowledge of the clinical impact of Stenotrophomonas maltophilia (SM) in cystic fibrosis (CF) patients. A systematic review according to the... (Review)
Review
To summarize the current knowledge of the clinical impact of Stenotrophomonas maltophilia (SM) in cystic fibrosis (CF) patients. A systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline recommendations, was performed through searches in PubMed and EMBASE databases, and CF National and International Registries websites from 2000 to 2022. Overall, 184 articles were initially retrieved, out of which 15 were selected and included in the review. Data form 6 Registries and 9 pertinent articles from the references of the studies selected were also considered, resulting in 30 studies in total. The prevalence of SM in patients with CF is increasing in Europe while it is declining in North America. The role of chronic colonization of SM on lung function and clinical status in CF patients is still under debate. The most recent studies suggested a pathogenic role of SM chronic infections in CF patients with an acceleration in lung function decline, an increase in hospitalization rates and an association with co-infection. Reflecting the uncertainty about the role of SM in CF, little is available about antibiotic therapeutic strategies for both acute exacerbations and chronic infections. Antimicrobial therapy should be performed in the acute exacerbations, while it may be reasonable to attempt eradication when the first colonization is identified. Nevertheless, it is not established which antibiotic regimen should be preferred, and overtreatment could contribute to the selection of antimicrobial-resistant strains. Further studies are warranted in this regard.
PubMed: 37728793
DOI: 10.1007/s10096-023-04648-z -
Infection Control and Hospital... Sep 2023From April 1, 2016, through March 31, 2022, growth of from clinical specimens at our academic medical center was significantly more likely during July-September than...
From April 1, 2016, through March 31, 2022, growth of from clinical specimens at our academic medical center was significantly more likely during July-September than during other calendar quarters.
Topics: Humans; Stenotrophomonas maltophilia; Gram-Negative Bacterial Infections; Anti-Bacterial Agents
PubMed: 36416200
DOI: 10.1017/ice.2022.280 -
Frontiers in Microbiology 2023To investigate the activity of antibiotic combinations against isolates and their associated biofilms.
OBJECTIVES
To investigate the activity of antibiotic combinations against isolates and their associated biofilms.
METHODS
Thirty-two clinical isolates with at least twenty-five different pulsotypes were tested. The antibacterial activity of various antibiotic combinations against seven randomly selected planktonic and biofilm-embedded strains with strong biofilm formation was assessed using broth methods. Extraction of bacterial genomic DNA and PCR detection of antibiotic resistance and biofilm-related genes were also performed.
RESULTS
The susceptibility rates of levofloxacin (LVX), fosfomycin (FOS), tigecycline (TGC) and sulfamethoxazole-trimethoprim (SXT) against 32 isolates were 56.3, 71.9, 71.9 and 90.6%, respectively. Twenty-eight isolates were detected with strong biofilm formation. Antibiotic combinations, including aztreonam-clavulanic (ATM-CLA) with LVX, ceftazidime-avibactam (CZA) with LVX and SXT with TGC, exhibited potent inhibitory activity against these isolates with strong biofilm formation. The antibiotic resistance phenotype might not be fully caused by the common antibiotic-resistance or biofilm-formation gene.
CONCLUSION
remained resistant to most antibiotics, including LVX and β-lactam/β-lactamases; however, TGC, FOS and SXT still exhibited potent activity. Although all tested isolates exhibited moderate-to-strong biofilm formation, combination therapies, especially ATM-CLA with LVX, CZA with LVX and SXT with TGC, exhibited a higher inhibitory activity for these isolates.
PubMed: 37408643
DOI: 10.3389/fmicb.2023.1186669