Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa are major causes of hospital-acquired infections and sepsis. Due to increasing antibiotic resistance, new treatments are needed. Mesenchymal stem cells (MSCs) have antimicrobial effects, which can be enhanced by preconditioning with antibiotics. This study investigated using antibiotics to strengthen MSCs against MRSA and P. aeruginosa. MSCs were preconditioned with linezolid, vancomycin, meropenem, or cephalosporin. Optimal antibiotic concentrations were determined by assessing MSC survival. Antimicrobial effects were measured by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antimicrobial peptide (AMP) gene expression. Optimal antibiotic concentrations for preconditioning MSCs without reducing viability were 1 μg/mL for linezolid, meropenem, and cephalosporin and 2 μg/mL for vancomycin. In MIC assays, MSCs preconditioned with linezolid, vancomycin, meropenem, or cephalosporin inhibited MRSA or P. aeruginosa growth at lower concentrations than non-preconditioned MSCs (p ≤ 0.001). In MBC assays, preconditioned MSCs showed enhanced bacterial clearance compared to non-preconditioned MSCs, especially when linezolid and vancomycin were used against MRSA (p ≤ 0.05). Preconditioned MSCs showed increased expression of genes encoding the antimicrobial peptide genes hepcidin and LL-37 compared to non-preconditioned MSCs. The highest hepcidin expression was seen with linezolid and vancomycin preconditioning (p ≤ 0.001). The highest LL-37 expression was with linezolid preconditioning (p ≤ 0.001). MSCs' preconditioning with linezolid, vancomycin, meropenem, or cephalosporin at optimal concentrations enhances their antimicrobial effects against MRSA and P. aeruginosa without compromising viability. This suggests preconditioned MSCs could be an effective adjuvant treatment for antibiotic-resistant infections. The mechanism may involve upregulation of AMP genes.
- MeSH
- Anti-Bacterial Agents pharmacology therapeutic use MeSH
- Antimicrobial Peptides MeSH
- Cephalosporins pharmacology MeSH
- Hepcidins pharmacology therapeutic use MeSH
- Humans MeSH
- Linezolid pharmacology therapeutic use MeSH
- Meropenem pharmacology therapeutic use MeSH
- Methicillin-Resistant Staphylococcus aureus * MeSH
- Mesenchymal Stem Cells * MeSH
- Microbial Sensitivity Tests MeSH
- Pseudomonas aeruginosa genetics MeSH
- Staphylococcal Infections * microbiology MeSH
- Vancomycin MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
INTRODUCTION: In the battle against multidrug-resistant bacterial infections, ceftazidime- avibactam (CZA) stands as a pivotal defense, particularly against carbapenemresistant (CR) Gram-negative pathogens. However, the rise in resistance against this drug poses a significant threat to its effectiveness, highlighting the critical need for in-depth studies about its resistance mechanisms. METHODS: This research focuses on the genomic characterization of CR- and CZA-resistant Escherichia coli (n=26) and Klebsiella pneumoniae (n=34) strains, harboring the blaNDM and/or blaOXA-48-like genes, at a major Lebanese tertiary care medical center, using whole genome sequencing (WGS). RESULTS: Our findings revealed a notable prevalence of blaNDM in all K. pneumoniae strains isolates, with 27 of these also harboring blaOXA-48. On the other hand, E. coli strains predominantly carried the blaNDM-5 gene. Whole genome sequencing (WGS) identified a predominance of ST383 among K. pneumoniae strains, which possessed a multi-replicon IncFIB-IncHI1B plasmid harboring the blaNDM-5. Additionally, various Inc group plasmids in K. pneumoniae across multiple sequence types were found to carry the blaNDM. Similarly, diverse STs of E. coli were observed to carry blaNDM-5 on different plasmids. DISCUSSION: The study underscores NDM carbapenemases as a paramount resistance mechanism in Lebanon,jeopardizing critical last-resort treatments. It also illuminates the role of varied sequence types and mobile genetic elements in the spread of NDM resistance,stressing the urgent need for strategies to mitigate this threat, especially in nosocomial infections.
- MeSH
- Anti-Bacterial Agents * pharmacology MeSH
- Azabicyclo Compounds * pharmacology MeSH
- Bacterial Proteins genetics metabolism MeSH
- beta-Lactamases * genetics metabolism MeSH
- Ceftazidime * pharmacology MeSH
- Tertiary Care Centers MeSH
- Carbapenem-Resistant Enterobacteriaceae genetics drug effects isolation & purification MeSH
- Escherichia coli * genetics drug effects MeSH
- Drug Combinations * MeSH
- Genome, Bacterial MeSH
- Carbapenems * pharmacology MeSH
- Klebsiella pneumoniae * genetics drug effects MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Drug Resistance, Multiple, Bacterial * genetics MeSH
- Plasmids genetics MeSH
- Gene Transfer, Horizontal MeSH
- Whole Genome Sequencing * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Lebanon MeSH
OBJECTIVES: The objective of this study was to develop a population pharmacokinetic model of meropenem in a heterogeneous population of patients with a serious bacterial infection in order to propose dosing optimisation leading to improved achievement of the pharmacokinetic/pharmacodynamic (PK/PD) target. METHODS: A total of 174 meropenem serum levels obtained from 144 patients during therapeutic drug monitoring were analysed using a non-linear mixed-effects modelling approach and Monte Carlo simulation was then used to compare various dosing regimens in order to optimise PK/PD target attainment. RESULTS: The meropenem volume of distribution of the patient population was 54.95 L, while clearance started at 3.27 L/hour and increased by 0.91 L/hour with each 1 mL/s/1.73 m2 of estimated glomerular filtration rate. Meropenem clearance was also 0.31 L/hour higher in postoperative patients with central nervous system infection. Meropenem administration by continuous infusion showed a significantly higher probability of attaining the PK/PD target than a standard 30 min infusion (95.3% vs 49.5%). CONCLUSIONS: A daily meropenem dose of 3 g, 6 g and 10.5 g administered by continuous infusion was shown to be accurate for patients with moderate to severe renal impairment, normal renal function to mild renal impairment and augmented renal clearance, respectively.
- MeSH
- Anti-Bacterial Agents * pharmacokinetics administration & dosage MeSH
- Bacterial Infections * drug therapy MeSH
- Models, Biological * MeSH
- Adult MeSH
- Infusions, Intravenous MeSH
- Middle Aged MeSH
- Humans MeSH
- Meropenem * pharmacokinetics administration & dosage MeSH
- Monte Carlo Method MeSH
- Drug Monitoring methods MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Dose-Response Relationship, Drug MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- MeSH
- Leukemia, Myeloid, Acute * drug therapy complications MeSH
- Anti-Bacterial Agents adverse effects therapeutic use MeSH
- Drug Resistance, Microbial MeSH
- C-Reactive Protein analysis MeSH
- Chemotherapy-Induced Febrile Neutropenia etiology drug therapy MeSH
- Soft Tissue Infections drug therapy pathology MeSH
- Carbapenems therapeutic use MeSH
- Humans MeSH
- Adolescent MeSH
- Treatment Failure MeSH
- Disease Progression MeSH
- Pseudomonas aeruginosa * pathogenicity drug effects MeSH
- Rectum diagnostic imaging pathology MeSH
- Check Tag
- Humans MeSH
- Adolescent MeSH
- Female MeSH
- Publication type
- Case Reports MeSH
Prevalence lékových interakcí v populaci kriticky nemocných je vysoká, ale často se jedná o potenciální lékové interakce s omezenou klinickou významností. Cílem tohoto sdělení je popsat mechanismus a management nikoliv nejčastějších, ale dle autorů klinicky nejvýznamnějších interakcí. Do přehledu jsme zahrnuli interakci karbapenemů a valproátu, inhibitorů CYP 3A4 a tikagreloru, enterální výživy a levodopy, kombinace léčiv prodlužujících QT interval a inhibitorů CYP 3A4 a kvetiapinu.
The prevalence of drug interactions in the critically ill is high, but these are often potential drug interactions of limited clinical relevance. This paper aims to describe the mechanism and management of not the most frequent but, according to the authors, the most clinically significant interactions. These top five interactions include carbapenems and valproate, CYP 3A4 inhibitors and ticagrelor, enteral nutrition and levodopa, combinations of QT prolonging drugs, and CYP 3A4 inhibitors and quetiapine.
- MeSH
- Enteral Nutrition MeSH
- Cytochrome P-450 CYP3A Inhibitors pharmacology MeSH
- Carbapenems pharmacokinetics pharmacology adverse effects MeSH
- Valproic Acid pharmacokinetics pharmacology MeSH
- Drug Interactions * MeSH
- Levodopa pharmacokinetics pharmacology MeSH
- Humans MeSH
- Drug-Related Side Effects and Adverse Reactions prevention & control MeSH
- Quetiapine Fumarate pharmacology MeSH
- Long QT Syndrome chemically induced etiology MeSH
- Ticagrelor pharmacology adverse effects MeSH
- Check Tag
- Humans MeSH
Delftia acidovorans je gramnegatívna aeróbna tyčinkovitá baktéria. Ochorenia u ľudí vyvoláva len raritne. Spôsobuje predovšetkým nozokomiálne nákazy, opisované častejšie u imunokompromitovaných pacientov v rámci všetkých vekových skupín. V odbornej literatúre bolo v posledných rokoch publikovaných niekoľko prípadov, v rámci ktorých sa uplatnila pri vzniku infekcií postihujúcich rôzne orgánové systémy. S ohľadom na častú rezistenciu voči aminoglykozidom a polymyxínom, ktoré mnohokrát slúžia ako záchranné liečivá pri komplikovaných infekciách gramnegatívnymi baktériami, nastáva nevyhnutne potreba jej rýchlej identifikácie s následne správne zvolenou liečbou. V kazuistike opisujeme prípad pacientky s rozsiahlym fluidothoraxom hrudníka v dôsledku infekcie baktériou Delftia acidovorans a sumarizujeme aktuálne dostupné informácie o infekciách spôsobených týmto zriedkavým patogénom.
Delftia acidovorans is a Gram-negative, aerobic, rod-shaped bacterium which causes infections in humans only rarely. It causes mostly nosocomial infections, described more frequently in immunocompromised patients across all age groups. In recent years, several cases involving this bacterium in infections affecting various organ systems have been published in the literature. With regard to its common resistance to aminoglycosides and polymyxins, which oftentimes serve as salvage therapy for complicated Gram-negative bacterial infections, there is inevitably a need for its quick identification followed by a correctly chosen treatment. This article describes a case of a patient with extensive pleural effusion due to Delftia acidovorans infection and also summarizes the currently available information on infections caused by this rare pathogen.
- MeSH
- Delftia acidovorans isolation & purification MeSH
- Empyema, Pleural * diagnosis etiology therapy MeSH
- Comorbidity MeSH
- Middle Aged MeSH
- Humans MeSH
- Meropenem administration & dosage therapeutic use MeSH
- Microbiological Techniques methods MeSH
- Pleural Effusion diagnosis therapy MeSH
- Tomography, X-Ray Computed methods MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Female MeSH
- Publication type
- Case Reports MeSH
The objective of this study was to assess the susceptibility of cefiderocol against multidrug-resistant carbapenemase-producing and nonproducing bacteria. The panel comprised 182 isolates of the order Enterobacterales, and 40 strains of Pseudomonas aeruginosa. Antimicrobial susceptibility testing has been performed using broth microdilution method according to the European Committee on Antimicrobial Susceptibility Testing recommendations. Mass spectrometry matrix-assisted laser desorption/ionization-time of flight mass spectrometry and carbapenemase-producing test were used to verify the presence of carbapenemases in clinical isolates. The genetic expression of single carbapenemases (blaKPC, blaOXA-48, blaNDM, blaVIM, blaIMP, blaGES) was determined by real-time polymerase chain reaction. Cefiderocol exhibited a good activity against the majority of strains tested in this study. Altogether, growth of 81.9% (n = 149) strains of the order Enterobacterales and 77.5% (n = 31) of P. aeruginosa isolates were inhibited at minimal inhibitory concentration (MIC) ≤2 mg/L. Values MIC50/MIC90 were 0.5/8 mg/L for enterobacteria, and 1/8 mg/L for P. aeruginosa. One isolate (Klebsiella pneumoniae) harboring two carbapenemases (blaOXA-48, blaNDM) had cefiderocol MIC 0.5 mg/L. In enterobacteria resistant to cefiderocol, blaNDM carbapenemase prevailed (43.3%, n = 29), followed by blaOXA-48 (31.3%, n = 21) and blaKPC (4.5%, n = 3). blaIMP (n = 8) and blaVIM (n = 1) metallo-β-lactamases dominated in cefiderocol-resistant P. aeruginosa (n = 9) isolates. Very good susceptibility (100%) to this drug showed blaGES-positive strains of P. aeruginosa (n = 8) and isolates resistant to meropenem without confirmed carbapenemase gene (n = 10). In this study, cefiderocol demonstrated potent activity against important nosocomial pathogens, therefore, therapeutic options of this drug against multidrug-resistant bacteria should be considered.
PURPOSE: In this review we present the status of the prevalence of bacteria resistant to antibiotics and the main antibiotic resistance genes that are reported in infections acquired in intensive care units (ICU) around the world. METHODS: A systematic review based on the PRISMA guide was carried out, from the Science Direct, Redalyc, Scopus, Hinari, Scielo, Dialnet, PLOS, ProQuest, Taylor, Lilacs and PubMed/Medline databases. Inclusion criteria of this review were original research study published in a scientific journal in a 10-year time span from 1 January 2017 and 30 April 2022. RESULTS: A total of 1686 studies were identified, but only 114 studies were considered eligible for inclusion. Klebsiella pneumoniae and Escherichia coli resistant to carbapenems and producers of extended-spectrum β-lactamases (ESBL) are the most frequently isolated pathogens in ICUs in Asia, Africa and Latin America. The blaOXA and blaCTX were antibiotic resistance genes (ARG) most commonly reported in different geographic regions (in 30 and 28 studies, respectively). Moreover, multidrug-resistant (MDR) strains were reported in higher frequency in hospital-acquired infections. Reports of MDR strains vary between continents, with the majority of publications being in Asia and between countries, with Egypt and Iran being highlighted. There is a predominance of few bacterial clones with MDR phenotype, for example, clonal complex 5 Methicillin-Resistant Staphylococcus aureus (CC5-MRSA) circulates frequently in hospitals in the United States, clone ST23-K. pneumoniae is reported in India and Iran, and clone ST260 carbapenemase-producing P. aeruginosa in the United States and Estonia. CONCLUSION: Our systematic review reveals that ESBL- and carbapenemase-producing K. pneumoniae and E. coli are the most problematic bacteria that are reported, mainly in tertiary hospitals in Asia, Africa, and Latin America. We have also found propagation of dominant clones with a high degree of MDR, becoming a problem due to its high capacity to cause morbidity, mortality and additional hospital costs.
Fosfomycin (FOS) has been recently reintroduced into clinical practice, but its effectiveness against multidrug-resistant (MDR) Enterobacterales is reduced due to the emergence of FOS resistance. The copresence of carbapenemases and FOS resistance could drastically limit antibiotic treatment. The aims of this study were (i) to investigate fosfomycin susceptibility profiles among carbapenem-resistant Enterobacterales (CRE) in the Czech Republic, (ii) to characterize the genetic environment of fosA genes among the collection, and (iii) to evaluate the presence of amino acid mutations in proteins involved in FOS resistance mechanisms. During the period from December 2018 to February 2022, 293 CRE isolates were collected from different hospitals in the Czech Republic. FOS MICs were assessed by the agar dilution method (ADM), FosA and FosC2 production was detected by the sodium phosphonoformate (PPF) test, and the presence of fosA-like genes was confirmed by PCR. Whole-genome sequencing was conducted with an Illumina NovaSeq 6000 system on selected strains, and the effect of point mutations in the FOS pathway was predicted using PROVEAN. Of these strains, 29% showed low susceptibility to fosfomycin (MIC, ≥16 μg/mL) by ADM. An NDM-producing Escherichia coli sequence type 648 (ST648) strain harbored a fosA10 gene on an IncK plasmid, while a VIM-producing Citrobacter freundii ST673 strain harbored a new fosA7 variant, designated fosA7.9. Analysis of mutations in the FOS pathway revealed several deleterious mutations occurring in GlpT, UhpT, UhpC, CyaA, and GlpR. Results regarding single substitutions in amino acid sequences highlighted a relationship between ST and specific mutations and an enhanced predisposition for certain STs to develop resistance. This study highlights the occurrence of several FOS resistance mechanisms in different clones spreading in the Czech Republic. IMPORTANCE Antimicrobial resistance (AMR) currently represents a concern for human health, and the reintroduction of antibiotics such as fosfomycin into clinical practice can provide further option in treatment of multidrug-resistant (MDR) bacterial infections. However, there is a global increase of fosfomycin-resistant bacteria, reducing its effectiveness. Considering this increase, it is crucial to monitor the spread of fosfomycin resistance in MDR bacteria in clinical settings and to investigate the resistance mechanism at the molecular level. Our study reports a large variety of fosfomycin resistance mechanisms among carbapenemase-producing Enterobacterales (CRE) in the Czech Republic. Our study summarizes the main achievements of our research on the use of molecular technologies, such as next-generation sequencing (NGS), to describe the heterogeneous mechanisms that reduce fosfomycin effectiveness in CRE. The results suggest that a program for widespread monitoring of fosfomycin resistance and epidemiology fosfomycin-resistant organisms can aide timely implementation of countermeasures to maintain the effectiveness of fosfomycin.
- MeSH
- Anti-Bacterial Agents pharmacology MeSH
- Drug Resistance, Bacterial genetics MeSH
- beta-Lactamases genetics MeSH
- Escherichia coli MeSH
- Fosfomycin * pharmacology MeSH
- Carbapenems pharmacology MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
