Multidrug-Resistant Gram-Negative Bacteria Infections: Current Epidemiology, Prognosis and Treatment Options

A special issue of Antibiotics (ISSN 2079-6382). This special issue belongs to the section "Antibiotic Therapy in Infectious Diseases".

Deadline for manuscript submissions: 31 January 2026 | Viewed by 7710

Special Issue Editor


E-Mail Website
Guest Editor
Emergency Room Infection Disease, Cotugno Hospital AORN dei Colli, 80131 Naples, Italy
Interests: infectious emergency; infection control; antimicrobial stewardship

Special Issue Information

Dear Colleagues,

In the rapidly evolving world of infectious diseases, multidrug-resistant Gram-negative bacteria (MDR-GNB) infections present significant threats to global public health. Understanding the prognosis and outcomes of MDR-GNB infections is crucial for healthcare providers and policymakers alike.

In this Special Issue, we welcome scholars to explore current epidemiology, prognosis, and treatment options for these infections, including but not limited to those caused by Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter baumannii.

Areas of interest include:

  1. The latest advances in understanding the mechanisms of resistance and transmission dynamics, as well as novel approaches to combatting these pathogens.
  2. Evaluation of the efficacy of existing treatment options and the exploration of emerging strategies to effectively prevent and manage these infections.
  3. Addressing the need for enhanced surveillance and rapid diagnostic methods to monitor the spread of multidrug-resistant Gram-negative bacteria and support optimal clinical decision making in the optimization of treatment plans.

This Special Issue will serve as a valuable resource for clinicians, researchers, and policymakers striving to reduce the impact of drug resistance on global health.

Dr. Novella Carannante
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

  • multidrug-resistant gram-negative bacteria
  • epidemiology and prognosis
  • antibiotic treatment options
  • antimicrobial resistance
  • infection control and antibiotic use

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.

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

18 pages, 1880 KB  
Article
Antimicrobial Resistance Profiles of Clinically Relevant Enterobacteriaceae Isolates: A Retrospective Study at a Southern Italian Hospital
by Giorgia Stornelli, Beatrice Marinacci, Valentina Puca, Benedetta Pellegrini, Roberta Zita Marulli, Ivana Cataldo, Francesca Sisto, Vittoria Perrotti, Arianna Pompilio, Mattia Mori, Pamela Di Giovanni and Rossella Grande
Antibiotics 2025, 14(9), 899; https://doi.org/10.3390/antibiotics14090899 - 5 Sep 2025
Viewed by 1089
Abstract
Background: The Enterobacteriaceae family is the most heterogeneous group of Gram-negative bacilli, with both environmental and clinical relevance. Although many of these species are part of the normal intestinal microbiota, species such as Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis are [...] Read more.
Background: The Enterobacteriaceae family is the most heterogeneous group of Gram-negative bacilli, with both environmental and clinical relevance. Although many of these species are part of the normal intestinal microbiota, species such as Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis are among the most common opportunistic pathogens, frequently responsible for nosocomial infections, including urinary tract infections, bacteraemia, and pneumonia. Based on these concerns, these species are increasingly being studied for their ability to develop antimicrobial resistance, often mediated by extended spectrum β-lactamase or carbapenemase production. The present study aims to analyse the antimicrobial resistance profiles of Enterobacteriaceae isolated from a southern Italian hospital focusing on the species of major clinical importance. Methods: A retrospective analysis was carried out on biological samples collected between 2019 and 2023 at the Microbiology Laboratory of the San Pio Hospital, Vasto (Italy). Eight hundred ninety patients were included, with an average age of 73 years. Bacterial identification was carried out using bacterial culture and biochemical methods, while antimicrobial sensitivity was assessed by using the automated Walk Away System. Results: The most frequently isolated species were Escherichia coli (63.2%), Klebsiella spp. (21.9%), and Proteus spp. (8.8%). All isolates showed resistance to at least one antimicrobial and most to more than four. The highest resistance rates were observed for Cefotaxime (16.0%), followed by Ampicillin (15.6%) and Ciprofloxacin (13.2%). Conclusions: The high prevalence of antimicrobial resistance among clinically relevant Enterobacteriaceae species is a growing clinical challenge. The results of this study, which describe the trend of resistance among Enterobacteriaceae in a local hospital, could help to raise awareness highlighting the urgent need for more advanced diagnostic tools and new therapeutic strategies to treat infections caused by multi-resistant microorganisms. Full article
Show Figures

Figure 1

13 pages, 717 KB  
Article
In Vitro Activity of Cefiderocol and Aztreonam/Avibactam Against Gram-Negative Non-Fermenting Bacteria: A New Strategy Against Highly Antibiotic-Resistant Infectious Agents
by Jan Závora, Václava Adámková, Alžběta Studená and Gabriela Kroneislová
Antibiotics 2025, 14(8), 762; https://doi.org/10.3390/antibiotics14080762 - 29 Jul 2025
Viewed by 1952
Abstract
Background/Objectives: Non-fermenting Gram-negative bacilli (NFGNB) represent a significant clinical challenge due to their intrinsic and acquired resistance, particularly in immunocompromised patients. Infections cause by NFGNB are associated with high morbidity and mortality, especially among patients with cystic fibrosis and hematologic malignancies. This study [...] Read more.
Background/Objectives: Non-fermenting Gram-negative bacilli (NFGNB) represent a significant clinical challenge due to their intrinsic and acquired resistance, particularly in immunocompromised patients. Infections cause by NFGNB are associated with high morbidity and mortality, especially among patients with cystic fibrosis and hematologic malignancies. This study aimed to assess the in vitro susceptibility of clinically relevant NFGNB isolates to two newer antibiotics, cefiderocol and aztreonam/avibactam, and an established antibiotic, trimethoprim/sulfamethoxazole. Methods: This retrospective, monocentric study analysed 94 NFGNB isolates (30 Pseudomonas aeruginosa, 30 Acinetobacter sp., 24 Stenotrophomonas maltophilia, and 10 Burkholderia cepacia complex). Susceptibility testing for cefiderocol, aztreonam/avibactam, and trimethoprim/sulfamethoxazole was conducted using gradient strip method. MIC values were interpreted using EUCAST breakpoints, ECOFFs, or alternative criteria when necessary. Results: All S. maltophilia isolates were susceptible to cefiderocol (FCR) and aztreonam/avibactam (A/A) based on ECOFFs, with one strain resistant to trimethoprim–sulfamethoxazole (COT). Burkholderia cepacia complex strains also showed high susceptibility to FCR, with only one isolate exceeding the ECOFF for A/A, and 20% resistant to COT. All Acinetobacter sp. isolates were susceptible to FCR; however, most MIC values clustered at or just below the ECOFF value. In P. aeruginosa, one isolate was resistant to FCR, and three isolates (10%) were resistant to A/A. Interestingly, confirmed carbapenemase producers remained susceptible to both FCR and A/A. Most A/A MIC values for P. aeruginosa were just below the ECOFF. Conclusions: Cefiderocol and aztreonam/avibactam demonstrated promising in vitro activity against clinically relevant NFGNB, including carbapenem-resistant strains. These findings support their potential role as therapeutic options for difficult-to-treat infections, particularly in immunocompromised patients. Full article
Show Figures

Figure 1

13 pages, 1371 KB  
Article
Multisite Infections Caused by Carbapenem-Resistant Klebsiella Pneumoniae: Unveiling the Clinical Characteristics and Risk Factors
by Jing Li, Shunjun Wu, Huanhuan Zhang, Xingxing Guo, Wanting Meng, Heng Zhao and Liqiang Song
Antibiotics 2025, 14(7), 721; https://doi.org/10.3390/antibiotics14070721 - 18 Jul 2025
Viewed by 1045
Abstract
Objectives: There is a scarcity of studies on multisite infections (MSIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). The primary objectives of this research were to determine the clinical characteristics of CRKP MSI, and the risk factors of infection and mortality. Methods: [...] Read more.
Objectives: There is a scarcity of studies on multisite infections (MSIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). The primary objectives of this research were to determine the clinical characteristics of CRKP MSI, and the risk factors of infection and mortality. Methods: Patients with a CRKP bloodstream infection (BSI) were enrolled retrospectively between January 2017 and December 2021 in Xijing Hospital, China. The risk factors for CRKP MSI and mortality were evaluated. The demographic data, clinical and microbiological characteristics, therapy and outcomes were analyzed. Results: Among 101 patients, 74.3% (75/101) had a diagnosis of CRKP MSI, while 25.7% (26/101) of CRKP non-MSI. The overall case fatality rate was 42.6% (43/101). Multivariate analysis indicated that previous surgery (OR 3.971, 95% CI 1.504–10.480, p = 0.005) and ICU admission (OR 3.322, 95% CI 1.252–8.816, p = 0.016) were independent risk factors for CRKP MSI. ICU admission (OR 4.765, 95% CI 1.192–19.054, p = 0.027), a Pitt bacteremia score (PBS) > 4 (OR 3.820, 95% CI 1.218–11.983, p = 0.022) and thrombocytopenia (OR 8.650, 95% CI 2.573–29.007, p < 0.001) were independent risk factors for mortality due to CRKP MSI. Conclusions: Our findings confirmed that CRKP MSIs were associated with poorer outcomes. To improve prognosis, early screening of individuals at the highest risk is vital. Full article
Show Figures

Figure 1

11 pages, 491 KB  
Article
Ciprofloxacin for the Treatment of Infections Caused by Carbapenemase-Producing Gram-Negative Bacteria
by Pablo Rubiñan, Belén Viñado, Nuria Fernández-Hidalgo, Nieves Larrosa, Abiu Sempere, David Campany, Dolors Rodríguez-Pardo, Juan José González-López, Xavier Nuvials, Ester del Barrio-Tofiño, Laura Escolà-Vergé and Ibai Los-Arcos
Antibiotics 2024, 13(12), 1138; https://doi.org/10.3390/antibiotics13121138 - 26 Nov 2024
Cited by 1 | Viewed by 2811
Abstract
Background: There is no experience with ciprofloxacin for the treatment of carbapenemase-producing Gram-negative bacteria (CP-GNB) infections. Methods: This is a retrospective single-centre study where we describe the clinical evolution of all consecutive adult patients who received ciprofloxacin monotherapy for the treatment of CP-GNB [...] Read more.
Background: There is no experience with ciprofloxacin for the treatment of carbapenemase-producing Gram-negative bacteria (CP-GNB) infections. Methods: This is a retrospective single-centre study where we describe the clinical evolution of all consecutive adult patients who received ciprofloxacin monotherapy for the treatment of CP-GNB infections. Primary outcomes were clinical failure (defined as death, lack of clinical improvement or a switch to another drug) at day 14 and 30-day all-cause mortality. Results: Nineteen patients were included. Fifteen (79%) were men, the median age was 74 years (IQR 66–79) and the median Charlson comorbidity index was five (IQR 3–6.5). The most frequent infections were: nine complicated urinary tract infections, three soft tissue infections and three intra-abdominal infections. Twenty CP-GNBs were isolated (one patient had a coinfection): nine VIM-type-producing Enterobacterales, nine OXA-48-type-producing Enterobacterales and two VIM-type-producing Pseudomonas aeruginosa. Six (32%) patients had positive blood cultures, and one presented with septic shock. The median duration of ciprofloxacin treatment was 14 days (IQR 10–15). One patient presented with clinical failure at day 14. There was no 30-day mortality. Two patients exhibited microbiological recurrence at day 90. There were no reported adverse effects. Conclusions: Monotherapy with ciprofloxacin may be an alternative treatment for selected, clinically stable patients with ciprofloxacin-susceptible CP-GNB infections. Full article
Show Figures

Figure 1

Back to TopTop