Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
8.7
4.6
Journals
Antibiotics
Special Issues
Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial...
share announcement

Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition

A special issue of Antibiotics (ISSN 2079-6382). This special issue belongs to the section "Antibiotics Use and Antimicrobial Stewardship".

Deadline for manuscript submissions: 31 August 2026 | Viewed by 4972

Special Issue Editor

Dr. Paolo Gaibani

E-Mail Website
Guest Editor
Department of Diagnostics and Public Health, Section of Microbiology, University of Verona, Verona, Italy
Interests: antimicrobial resistance; genomic analysis; molecular epidemiology
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Multi-drug resistant (MDR) Gram-negative bacilli (BNG) represent a serious threat among antimicrobials resistances. MDR-GNB are resistant to multiple antimicrobial molecules, thus reducing the antimicrobial options available for treating infections sustained by these microorganisms. Among them, extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, carbapenem-resistant Enterobacteriales (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB), and MDR Pseudomonas aeruginos represent the most urgent threat for which there is an imminent need for novel antimicrobial treatment strategies. To counteract the paucity of the antimicrobial molecules for the treatment of infections due to MDR-GNB, multidisciplinary approaches are required. In this context, innovative strategies for diagnosis, infection control and antimicrobial stewardship are the key factors. In this Special Issue, we invite authors to send in their manuscripts on the following areas of interest:

  • Novel in vitro diagnostic tools for MDR-GNB detection and antimicrobial susceptibility testing;
  • The molecular epidemiology of Gram-negative pathogens and resistance mechanisms;
  • The evaluation of antimicrobial treatment regimens for MDR-GNB;
  • New drugs against MDR-GNB: clinical use, in vitro susceptibility testing and emerging resistance.
  • Pharmacodynamics/pharmacokinetics (PK/PD) parameter to optimise antimicrobial treatments for MDR-GNB

Dr. Paolo Gaibani
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Antibiotics is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2900 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • pharmacodynamics/pharmacokinetics (PK/PD)
  • enterobacterales
  • carbapenemase
  • novel molecules
  • antimicrobial resistance

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Related Special Issue

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

15 pages, 1530 KB  
Article
Synergistic Activity of Eugenol, Cinnamaldehyde, and Carvacrol in Combination with Different Antibacterial Agents Against Multidrug-Resistant Gram-Negative Clinical Isolates
by Rocco Latorre, Maria Chiara Valerii, Irene Ferrari, Marco Benati, Enzo Spisni, Alessia Pardo, Massimo Albanese, Caterina Signoretto, Giuseppe Lippi and Paolo Gaibani
Antibiotics 2026, 15(4), 391; https://doi.org/10.3390/antibiotics15040391 - 11 Apr 2026
Viewed by 657
Abstract
Background/Objectives: The WHO has identified carbapenem-resistant Acinetobacter baumannii (CRAb) and carbapenem-producing Enterobacterales (CPE) as the “critical priority” group of multidrug-resistant (MDR) organisms for which new therapeutic strategies are urgently needed. Here, we evaluated the in vitro synergistic activity of eugenol, cinnamaldehyde, and [...] Read more.
Background/Objectives: The WHO has identified carbapenem-resistant Acinetobacter baumannii (CRAb) and carbapenem-producing Enterobacterales (CPE) as the “critical priority” group of multidrug-resistant (MDR) organisms for which new therapeutic strategies are urgently needed. Here, we evaluated the in vitro synergistic activity of eugenol, cinnamaldehyde, and carvacrol in combination with β-lactams, gentamicin, or colistin against MDR Gram-negative bacteria (GNB). Methods: We selected seven MDR-GNB clinical isolates including CRAb, ESBL-producing and CPE clinical isolates displaying different antimicrobial susceptibility profiles. The genomes of clinical isolates were characterized by whole-genome sequencing and synergy testing was performed with checkerboard assay. Results: Our results demonstrate that eugenol, cinnamaldehyde, and carvacrol in combination with colistin exhibited synergistic activity (FICI < 0.5) against MDR-GNB clinical isolates ranging from 37.5 to 50%, while the effect was almost indifferent in combination with different β-lactam molecules or gentamicin against 87.5–100% of MDR-GNB strains. The synergistic interaction of eugenol, cinnamaldehyde, and carvacrol with colistin induced a statistically significant reduction (p < 0.05) in the MIC values compared with the molecules tested alone. Conclusions: Our data demonstrate that this synergistic interaction was not affected by different antimicrobial resistance genes and/or different antimicrobial susceptibility profiles. In conclusion, our results suggest that eugenol, cinnamaldehyde, and carvacrol in combination with colistin represent a potential strategy for the treatment of MDR-GNB pathogens and limit their diffusion. Full article
(This article belongs to the Special Issue Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition)
►▼ Show Figures

Figure 1

17 pages, 354 KB  
Article
Multicenter Analytical Performance Evaluation of the BD Phoenix NMIC-461 Panel for Carbapenemase Classification and Antimicrobial Susceptibility Testing of Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter spp.
by Jingjia Zhang, Liying Sun, Ge Zhang, Wei Kang, Tong Wang, Jin Li, Haotian Gao, Qiwen Yang, Kuixia Sun, Qian Wang and Hongli Sun
Antibiotics 2026, 15(3), 286; https://doi.org/10.3390/antibiotics15030286 - 12 Mar 2026
Viewed by 463
Abstract
Objectives: To evaluate the capability of the BD Phoenix NMIC-461 panel in the detection and classification of carbapenemase production and antimicrobial susceptibility testing of 10 antimicrobial agents among Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter spp. Methods: A total of 714 non-repetitive clinical [...] Read more.
Objectives: To evaluate the capability of the BD Phoenix NMIC-461 panel in the detection and classification of carbapenemase production and antimicrobial susceptibility testing of 10 antimicrobial agents among Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter spp. Methods: A total of 714 non-repetitive clinical isolates from three tertiary hospitals in China were enrolled. Carbapenemase production was confirmed by the modified carbapenem inactivation method (mCIM), while carbapenemase typing was validated by polymerase chain reaction (PCR) and Sanger sequencing. Antimicrobial susceptibility testing (AST) for ten antimicrobial agents was performed using broth microdilution (BMD) as the reference method. Results: The sensitivity and specificity of carbapenemase detection were 98.8% (95% CI, 96.6–99.6) and 92.4% (95% CI, 89.5–94.6) separately compared to sequencing. Classification accuracy was compromised by carbapenemase-positive unclassified strains, particularly reducing sensitivity for Enterobacterales. Excluding unclassified strains, the sensitivity and specificity were: for class A, 100% (95% CI, 94.0–100) and 97.3% (95% CI, 95.6–98.4); for class B, 97.1% (95% CI, 89.7–99.2) and 97.6% (95% CI, 96.0–98.6); and for class D, 94.0% (95% CI, 87.9–97.3) and 99.1% (95% CI, 97.8–99.7). The panel was subject to limitations for carbapenemase detection when applied to Pseudomonas aeruginosa. The NMIC-461 panel demonstrated excellent performance for ten BMD-evaluated agents across four bacterial categories, with essential agreement (EA) exceeding 95% and category agreement (CA) exceeding 90% except for Levofloxacin, and major error (ME) and very major error (VME) rates below 3% and 1.5%, respectively. Conclusions: The BD Phoenix NMIC-461 panel provides reliable AST results for commonly encountered Gram-negative bacterial isolates. Regarding carbapenemase detection, the panel demonstrates high sensitivity but only moderate specificity in classifying carbapenemase-producing organisms (CPO), with a relatively high proportion of positive unclassified isolates among Enterobacterales and low specificity for P. aeruginosa. Overall, the implementation of NMIC-461 testing holds promise for significantly reducing turnaround time in both carbapenemase detection and classification. Full article
(This article belongs to the Special Issue Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition)
►▼ Show Figures

Figure 1

13 pages, 1725 KB  
Article
Detection of ARGs from Gram-Negative Bacteria in Positive Blood Cultures Using a Microarray-Based System: Towards a Molecular Antibiotic Susceptibility Assay
by Cataldo Maria Mannavola, Giordana Cafaro, Barbara Fiori, Roberto Rosato, Francesca Romana Monzo, Tiziana D’Inzeo, Brunella Posteraro, Maurizio Sanguinetti and Flavio De Maio
Antibiotics 2025, 14(12), 1221; https://doi.org/10.3390/antibiotics14121221 - 4 Dec 2025
Viewed by 757
Abstract
Background/Objectives: Antimicrobial resistance (AMR) represents a major global health challenge, driving the need for rapid and accurate diagnostic tools. Novel molecular assays, including multiplex PCR and DNA microarray-based systems, have emerged to detect antimicrobial resistance genes (ARGs) alongside bacterial identification. Methods: [...] Read more.
Background/Objectives: Antimicrobial resistance (AMR) represents a major global health challenge, driving the need for rapid and accurate diagnostic tools. Novel molecular assays, including multiplex PCR and DNA microarray-based systems, have emerged to detect antimicrobial resistance genes (ARGs) alongside bacterial identification. Methods: In this study, we evaluated the performance of the HybriSpot12 PCR AUTO (HS12a) system and the MDR Direct Flow Chip (MDR-FC) Kit—an automatic microarray assay based on reverse hybridization—for the detection of ARGs directly from positive blood culture (PBC) samples. A total of 111 Gram-negative bacterial isolates (92 Enterobacterales, 14 Acinetobacter baumannii, and 6 Pseudomonas spp.), previously characterized by whole-genome sequencing (WGS), were each used to generate a PBC, which was then analyzed with the HS12a/MDR-FC assay. Results: We demonstrated perfect agreement for the detection of macrolide resistance genes across all bacterial species and high agreement for genes conferring resistance to sulfonamides and β-lactams. In contrast, aminoglycoside resistance genes showed only moderate agreement, with minor discrepancies observed in Klebsiella pneumoniae and Escherichia coli, largely attributable to specific SNP variations. Conclusions: The HS12a/MDR-FC assay includes 51 ARGs, though not all were represented in our isolate set, and some false negatives were observed. Despite these limitations, its broad coverage and rapid turnaround remain advantageous compared to other rapid assays with fewer targets. Future refinements should aim at broader gene coverage, inclusion of key mutations, and detection of emerging variants, making this approach a promising tool for rapid AMR surveillance and antimicrobial stewardship. Full article
(This article belongs to the Special Issue Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition)
►▼ Show Figures

Figure 1

14 pages, 821 KB  
Article
Correlation Between Antimicrobial Consumption and Resistance in Klebsiella pneumoniae During the COVID-19 Pandemic Using Dynamic Regression Models: A Quasi-Experimental Epidemiological Time-Series Study
by Paul Laffont-Lozes, Florian Salipante, Paul Loubet, Catherine Dunyach-Remy, Jean-Philippe Lavigne, Albert Sotto and Romaric Larcher
Antibiotics 2025, 14(10), 1020; https://doi.org/10.3390/antibiotics14101020 - 14 Oct 2025
Viewed by 925
Abstract
Background/Objectives: The COVID-19 pandemic has been reported to impact antimicrobial consumption (AMC) and antimicrobial resistance (AMR) worldwide. We aimed to assess this correlation in Klebsiella pneumoniae before and during the COVID-19 pandemic and to estimate the burden of each antibiotic. Methods: [...] Read more.
Background/Objectives: The COVID-19 pandemic has been reported to impact antimicrobial consumption (AMC) and antimicrobial resistance (AMR) worldwide. We aimed to assess this correlation in Klebsiella pneumoniae before and during the COVID-19 pandemic and to estimate the burden of each antibiotic. Methods: We collected data on AMC of penicillins and beta-lactamase inhibitors (PBIs), anti-pseudomonal activity penicillins and beta-lactamase inhibitors (AAPBIs), cephalosporins, carbapenems, fluoroquinolones, aminoglycosides, and AMR in K. pneumoniae strains. The correlation between AMC and AMR was studied using dynamic regression models. Results: Overall, AMC of AAPBIs and fourth-generation cephalosporin increased, while fluoroquinolone consumption and AMR in the 2862 K. pneumoniae strains analyzed decreased. However, during the first year of the pandemic, we reported an increase in AMC and AMR. We found that 46% to 48% of the increase in cephalosporin, AAPBI, and fluoroquinolone resistance was explained by increased cephalosporin and fluoroquinolone consumption, 55% of the increase in PBI resistance was explained by increased PBI, cephalosporin, and fluoroquinolone consumption, and 58% of the increase in aminoglycoside resistance was explained by increased aminoglycoside consumption. Conclusions: During the COVID-19 pandemic, the increase in AMR in K. pneumoniae was correlated with the increase in AMC of several antibiotics, mainly cephalosporins and especially fluoroquinolones. Full article
(This article belongs to the Special Issue Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition)
►▼ Show Figures

Figure 1

14 pages, 1389 KB  
Article
Lack of Association Between qacE and qacE∆1 Gene Variants and Sodium Hypochlorite Resistance in Clinical Isolates of ESBL- and Carbapenemase-Producing Klebsiella spp. and Enterobacter spp., from Gaborone, Botswana
by Pearl Ntshonga, Tlhalefo Dudu Ntereke, Tshiamo Zankere, Daniel Paul Morse, Garesego Koto, Irene Gobe and Giacomo Maria Paganotti
Antibiotics 2025, 14(7), 662; https://doi.org/10.3390/antibiotics14070662 - 30 Jun 2025
Cited by 3 | Viewed by 1494
Abstract
Background: The qacE gene and its variant, qacE∆1, have been associated with resistance to antimicrobials and biocides. This poses a threat to infection prevention, control and treatment. Several studies investigated this relationship with conflicting results. The aim of this research was [...] Read more.
Background: The qacE gene and its variant, qacE∆1, have been associated with resistance to antimicrobials and biocides. This poses a threat to infection prevention, control and treatment. Several studies investigated this relationship with conflicting results. The aim of this research was to determine the prevalence of qacE and qacE∆1 in clinical extended spectrum β-lactamase- (ESBL) and carbapenemase-producing Klebsiella spp. and Enterobacter spp. and elucidate the association of these genes with resistance to sodium hypochlorite. Methods: This study included 216 isolates of ESBL- and carbapenemase-producing multidrug-resistant (MDR) Klebsiella spp. and Enterobacter spp. These isolates were identified by VITEK-2 analyser. The MIC and MBC of sodium hypochlorite were determined using the microbroth serial-dilution method. PCR was used to detect gene variants. A regression analysis investigated any association between qacE genotypes, MIC and MBC, as well as antimicrobial drug resistance profiles. Results: Overall, there was a high prevalence of qacE and qacE∆1 variants (84.7%; 95% CI, 79.2–89.2). There was a high prevalence of qacE∆1 (80.6%; 95% CI, 74.6–85.6) as compared to qacE (15.3%, 95% CI, 10.8–20.8). The MIC50 and MIC90 of the isolates ranged between 7031 mg/L and 9375 mg/L and 14,060 mg/L and 18,750 mg/L, respectively, while the MBC ranged from 48,750 mg/L to 18,750 mg/L. There was no association between qacE genotypes and high MIC and MBC as well as antimicrobial drug resistance. Conclusions: The MIC and MBC of sodium hypochlorite are higher than what is currently used for disinfection in Botswana. There is a high prevalence of qacE and qacE∆1; however, these genes do not seem to be associated with resistance to sodium hypochlorite. Full article
(This article belongs to the Special Issue Multi-Drug Resistant Gram-Negative Infections: Molecular Epidemiology, Microbiological Diagnosis, and Antimicrobial Treatment, 2nd Edition)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop