Background/Objectives: Tuberculosis remains a major public health challenge due to the persistence of Mycobacterium tuberculosis (Mtb) and the emergence of multidrug-resistant strains. In this study, Pep-H, an HNP-1-derived antimicrobial peptide with the sequence RRYGTCIYQGRLWAF-NH2, was used as a compact scaffold to examine how single-residue substitutions at the Cys position affected its biological and functional profile. Methods: A focused single-position substitution panel was generated by replacing Cys with Trp, Ala, Arg, or Met while preserving peptide length and sequence context, and the analogs were computationally prioritized according to their predicted antitubercular potential and contrasting side-chain properties. The peptides were synthesized, purified, characterized by HPLC and mass spectrometry, and evaluated for activity against Mtb H37Rv, cytotoxicity, hemolysis, ethidium bromide accumulation, and DPPH radical scavenging. Results: Pep-H retained the most favorable profile, showing the highest antimycobacterial potency, low hemolysis, favorable selectivity indices, enhanced ethidium bromide accumulation, and the strongest antioxidant response. All Cys substitutions reduced antimycobacterial activity, indicating that none of the tested residues reproduced the integrated biological profile of Pep-H. Conclusions: The contrasting outcomes of the Arg- and Met-containing analogs suggest that increased cationicity or sulfur retention alone was insufficient, while supporting a multifactorial contribution of Cys side-chain chemistry and the local GTCIY environment.
BACKGROUND:While equine patient-mediated introduction of A. baumannii into hospital settings has been documented, its environmental dissemination and the risk of hospital-acquired surgical site infection remain poorly understood. OBJECTIVE:Therefore, this descriptive observational study examined (a) the environmental distribution of Acinetobacter spp. in an equine university hospital, (b) the impact of the implementation of new hygiene protocols, (c) the specification of resistance patterns, and (d) the evaluation of the presence of Acinetobacter spp. in hospital-acquired wound infections. METHODS:During three sampling periods, environmental samples of the stables, the treatment, and surgery areas were collected before and after cleaning and disinfection. After sampling period 1 (December 2021), the cleaning routines were optimized by reviewing the cleaning and disinfection process, as well as including further surfaces in the cleaning schedule for January 2022). This was followed by a second (February 2022) and a third (June 2022) sampling period. During sampling periods 1 and 2, 76 surfaces were sampled; in sampling period 3, only 21 critical surfaces were examined. Samples were cultured on selective agar plates and incubated at 37 °C, with bacterial growth evaluated after 24-48 h. Wound swabs were enriched in broth before culturing. Bacteria were identified using MALDI-TOF mass spectrometry. During the first sampling period, antibiotic susceptibility testing was performed using broth microdilution according to CLSI-vet standards. RESULTS:During each sampling period, Acinetobacter spp. was detected in at least one sample in each of the different areas; however, there was a reduced detection rate from sampling period 1 throughout sampling period 3. The isolates were highly resistant against beta-lactam and macrolide antibiotics but mostly sensitive to fluroquinolones (enrofloxacin, 2.2% resistance; marbofloxacin, 0.0% resistance), aminoglycosides (gentamicin, 6.5% resistance; kanamycin, 8.7% resistance), and tetracyclines. Acinetobacter spp. was not detected in surgical site infections. CONCLUSIONS:Environmental persistence of Acinetobacter spp. in an equine clinical setting does not necessarily translate into surgical site infections. Through prudent antibiotic use, the antibiotic susceptibility of the isolates may be perceived.
Background/Objectives: Inappropriate antibiotic prescribing in primary healthcare (PHC) contributes to bacterial antimicrobial resistance (AMR). Antibiotic stewardship, including measuring the appropriateness of antibiotic prescribing using quality indicators, is a priority in PHC where most antibiotics are used. Using previously developed WHO AWaRe classification-based quality indicators, we aim to test the clinimetric properties of 13 acute respiratory tract infection (RTI) quality indicators and qualitatively explore factors influencing PHC antibiotic prescribing in South Africa. Methods: We conducted a mixed-methods exploratory feasibility study using point prevalence surveys (PPSs) with clinimetric assessment and prescriber interviews. PPSs were conducted at four PHC facilities in Gauteng province that had taken part in previous PPS studies, alongside face-to-face interviews with PHC personnel. Results: In total, 52/52 (100%) RTI patients received antibiotics. Four (30.8%) indicators achieved scores above 85%, while six (46.2%) scored below 50%. All indicators had applicability scores ≥10%. Twelve (92.3%) indicators had a measurability score of 100%, while one (7.7%) had a measurability score <75%. Twelve (92.3%) indicators met all predefined acceptable scores for applicability and measurability. No participant knew of the WHO’s AWaRe classification and none had specific training on antibiotic prescribing and AMR. They also had no antibiotic stewardship programmes (ASPs) or specific antibiotic-prescribing guidelines at their facilities. Key factors affecting antibiotic prescribing included shortages, patient expectations and fear of complications. Conclusions: The indicators demonstrated acceptable clinimetric properties in South Africa. Robust locally validated indicators, combined with ASPs promoting the AWaRe classification, are imperative for accurate assessment and improvement of antibiotic prescribing.
Background: Antimicrobial resistance (AMR) is a growing global health threat, disproportionately affecting low- and middle-income countries such as Sudan. Conflict-related health system disruption has further intensified inappropriate antibiotic use and weakened stewardship capacity. Objective: This narrative review synthesizes contemporary evidence on antibiotic prescribing practices in Sudan, with emphasis on ambulatory care, and examines their implications for AMR control in the context of ongoing conflict. Methods: A non-systematic, structured narrative review was conducted successfully. PubMed, Google Scholar, WHO/EMRO databases, and Sudan’s National Action Plan (NAP) materials were examined for literature published between January 2010 and December 2025. Peer-reviewed research, government guidelines, surveillance reports, and gray literature were among the eligible sources. A total of 78 studies were included after titles, abstracts, and full texts were screened. Two reviewers independently confirmed the data extraction, and the synthesis aligned with SANRA guidelines. Results: Antibiotic prescribing in Sudan is frequently inappropriate, particularly in ambulatory and community settings, where empirical treatment, polypharmacy, and extensive use of Watch antibiotics are common. Alignment with WHO AWaRe recommendations remains suboptimal. Recent clinical and molecular evidence demonstrates increasing multidrug resistance among Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus, including ESBL production and emerging carbapenemase genes (e.g., NDM 1, IMP 1). Conflict-related disruptions—such as reduced laboratory capacity, supply chain breakdown, and unregulated community dispensing—have further accelerated AMR. Pilot stewardship interventions show promise but remain limited in scale. Conclusions: Inappropriate antibiotic use in Sudan is driven largely by ambulatory and community practices and has been exacerbated by conflict. Strengthening stewardship beyond hospitals, enforcing prescription-only regulations, operationalizing the AWaRe framework, and aligning empirical therapy with local resistance patterns are critical for mitigating AMR in Sudan and similar conflict-affected settings.
It is crucial to consider newer antibiotics with activity against anaerobes and Helicobacter pylori, given their healthcare importance, and the constantly growing antibiotic resistance/multidrug resistance, which complicates the therapy. The aim of this review was to emphasize certain recently approved or still-under-investigation antibiotics with potential benefits for treating Clostridioides difficile infections (CDIs), other anaerobic infections, and those caused by H. pylori, covering recent data from articles published primarily in 2020-2026. Given the limited number of antibiotics for treating CDI and fidaxomicin nonavailability in many countries, it is necessary to conduct more extensive laboratory and clinical studies of promising antibiotics such as ibezapolstat, delafloxacin, lascufloxacin, omadacycline, eravacycline, ridinilazole, and CRS3123. Against Bacteroides fragilis group species, delafloxacin and eravacycline showed good activity. Research on rifasutenizol for bacterial vaginosis, sarecycline and nadifloxacin for acne vulgaris and amixicile for periodontal diseases needs to be expanded. For H. pylori infection, delafloxacin, sitafloxacin, nemonoxacin, zoliflodacin, and rifasutenizol may improve the suboptimal success of most eradication regimens. However, more efforts, in coordination between medical, scientific, manufacturing, and government representatives, should ensure wider access to and research on the newer antibacterials. Establishing more research groups, careful examination of market issues, and additional approaches, such as nanomaterials, efflux pump inhibitors, phage therapy, and CRISPR-Cas systems, should be beneficial. Notwithstanding the difficulties, there are many opportunities to promote research on and potential use of newer antibiotics which show advantages over the older antibacterials, and to make them available to numerous countries and patients worldwide.
Background: Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality globally, with serious implications in Lebanon. Both international and local guidelines advocate for empirical antibiotic treatments by illness severity, yet the extent to which these are followed in Lebanese hospitals is unclear. This research examined the adherence to CAP treatment guidelines and its association with clinical outcomes. Methods: We retrospectively studied adults admitted to two Lebanese referral hospitals (Mount Lebanon University Medical Center and Ain Wazein Medical Village) from April 2011 to March 2025 with CAP. Adherence to empirical antibiotic regimens was determined based on the guidelines from the Lebanese Society of Infectious Diseases and Clinical Microbiology, American Thoracic Society/Infectious Diseases Society of America, and British Thoracic Society/National Institute for Health and Care Excellence. The outcomes assessed were in-hospital mortality, Intensive Care Unit (ICU) admission, and length of hospital stay (LOS). We used logistic and linear regression analyses, adjusting for demographic and clinical variables. Results: A total of 337 patients were included with an average age of 61 years; 53.7% were male, 51.6% were admitted to the ICU, and the in-hospital mortality rate was 27%. In general, 65.6% of the treatment regimens adhered to at least one guideline. The combination of β-lactam and macrolide was the most common, used in 87.8% of cases, while monotherapy was administered in 31.8% of cases and included β-lactam, macrolide, fluoroquinolone, and other antibiotics; most monotherapies were non-adherent to guidelines, except for selected fluoroquinolone monotherapy cases that may be considered guideline-concordant under ATS/IDSA recommendations depending on clinical context. Adherence to guidelines did not significantly affect mortality rates (25.8% vs. 29.3%), ICU admissions (52.5% vs. 50.0%), or length of stay (11.4 vs. 9.3 days). Multivariate analysis revealed that older age (OR 1.025, 95% CI 1.008-1.042) and ICU admission (OR 1.024, 95% CI 1.012-1.039) were independent predictors of adverse outcomes, whereas guideline adherence, comorbidities, and inflammatory markers were not independently linked. Surprisingly, mortality was higher among younger patients (average age 58 vs. 67 years, p < 0.001). Conclusions: Although guideline-concordant empirical therapy was prevalent in this two-center Lebanese retrospective population, it did not independently correlate with length of stay following adjustment, ICU admission, or in-hospital mortality. Patient-related and clinical factors, such as the severity of the illness, may have an impact on observed differences in outcomes, which should be taken as relationships.
BACKGROUND/OBJECTIVES:Patients in long-term care hospitals (LTCHs) are at increased risk of harboring antimicrobial-resistant organisms due to frequent healthcare exposure and multiple comorbidities. This retrospective observational study aimed to compare the antimicrobial susceptibility of bacterial isolates from LTCH-onset infections (LTCHIs) with those from community-acquired infections (CAIs) in elderly patients. METHODS:This study was conducted at a 700-bed urban tertiary university hospital and included patients aged ≥65 years with positive cultures for bacteremia, lower respiratory tract infections (LRTIs), or urinary tract infections (UTIs) within 48 h of admission. Medical records, including antimicrobial susceptibility test results, were reviewed for a total of 1780 patients and their isolates. Antimicrobial susceptibility patterns were compared between LTCHI and CAI patients. RESULTS:Patients with LTCHI exhibited significantly higher antimicrobial non-susceptibility than those with CAIs across multiple pathogens and antimicrobial classes (p < 0.05). In bacteremia, Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae from LTCHI cases showed increased non-susceptibility to β-lactams and fluoroquinolones. In LRTIs, Pseudomonas aeruginosa and Acinetobacter baumannii demonstrated high non-susceptibility to carbapenems (52.9% and 90%, respectively) and aminoglycosides. In UTIs, LTCHI isolates exhibited broader resistance among Enterobacterales and P. aeruginosa. Notably, the proportion of multidrug-resistant organisms, including carbapenem-resistant Enterobacterales (15.4-50.0%) and carbapenem-resistant Acinetobacter baumannii (90.5%), was substantially higher in the LTCHI group across all infection sites. CONCLUSIONS:Elderly patients with LTCHI are more likely to harbor antimicrobial-resistant pathogens than those with CAIs. Careful consideration of LTCHI origin is therefore essential for empirical antibiotic selection and for strategies aimed at limiting further resistance.
Background/Objectives: Resistant pathogenic bacteria and fungi are a growing problem worldwide; therefore, the discovery of new active ingredients is an important challenge for which the functionalization of natural terpenes with biologically active heterocycles can provide a basis. To reach this goal, a series of 1,4-disubstituted-1,2,3-triazole conjugates was designed and synthesized starting from commercially available α-santonin. Methods: The key azido derivative intermediate was prepared according to literature procedures via Michael addition between dehydrosantonin and the TMSN3/AcOH/Et3N system at its highly reactive α-methylene-γ-lactone motif. Subsequently, the obtained azide was applied to regioselective Huisgen 1,3-dipolar cycloaddition reaction with a wide range of terminal alkynes bearing N-, S- and O-heterocycles. These include pyridine, pyrimidine, purine, quinoline, indol, or coumarin to afford the sesquiterpene-heterocycle chimaeras. All triazole conjugates were screened for in vitro antiproliferative activity by MTT assay against HeLa, MDA-MB231, SiHa, MCF-7 and A2780 human cancer cell lines compared with fibroblast cells (NIH/3T3) to check their cytotoxicity and antimicrobial effects on two Gram-positive (B. subtilis, S. aureus) pathogenic bacteria, two Gram-negative (E. coli and P. aeruginosa) pathogenic bacteria, and two yeasts (C. krusei and C. albicans). Results: The results indicated that most of the examined compounds expressed weak activity against human cell lines, while some of them showed moderate activity against S. aureus (up to 99% inhibition at 100 µg/mL conc.), C. krusei (up to 51% inhibition at 10 µg/mL conc.) and C. albicans (up to 52% inhibition at 10 µg/mL conc.). Conclusions: Further structural modification of the best, selective antibacterial and antifungal compounds may open the possibility to the development of effective natural sesquiterpene-based selective antimicrobial agents.
Background: The World Health Organization has identified the growing ineffectiveness of antibiotics against resistant pathogens as a global threat to public health, linked to increased morbidity and mortality. In this context, Pseudomonas aeruginosa stands out as a multidrug-resistant, biofilm-forming pathogen whose biofilm formation increases its tolerance to antimicrobials, which has driven the development of anti-virulence strategies as a therapeutic alternative. In this regard, the present study aimed to evaluate extracts and compounds from Piper species in assays targeting the inhibition of biofilm and virulence factors in Pseudomonas aeruginosa, as well as their anti-quorum sensing activity using Chromobacterium violaceum as a biosensor model. Methods: For this purpose, quorum sensing interference was first assessed through inhibition of violacein production using C. violaceum ATCC 12472 as a biosensor model. The modulation of virulence-associated phenotypes in P. aeruginosa ATCC BAA-47 was subsequently examined through inhibition of biofilm formation by crystal violet staining and spectrophotometric quantification of elastase, protease and pyocyanin production. Results: It was found that extracts from P. aduncum, P. sucrense, P. grande, and P. cumanense inhibited biofilm formation in P. aeruginosa and showed potential activity against quorum sensing in the C. violaceum model, while P. ceanothifolium exhibited only antibiofilm activity. Furthermore, hydroquinone-type compounds and benzoic acid derivatives reduced biofilm formation and virulence factors in P. aeruginosa. Conclusions: The results obtained demonstrate antibiofilm and anti-virulence activity, as well as a possible modulation of quorum sensing in model systems, suggesting that Piper species represent a promising source of bioactive compounds.
Periprosthetic joint infection (PJI) remains one of the most severe and complex complications following joint arthroplasty. With the global increase in primary hip and knee replacements, the clinical and economic burden associated with PJI continues to grow. Although relatively uncommon, PJI is linked to substantial morbidity, elevated mortality, and significantly higher healthcare costs compared to aseptic revision procedures. The challenge is compounded by the intricate pathogenesis of biofilm-forming microorganisms, heterogeneous clinical presentations, and the lack of universally standardised diagnostic criteria. This review provides an integrated overview of current evidence concerning the pathophysiology, risk factors, and microbiological patterns associated with PJI. Contemporary diagnostic pathways based on the Musculoskeletal Infection Society/International Consensus Meeting (MSIS/ICM) criteria are summarised, including the utility and limitations of established serological markers, emerging synovial biomarkers such as alpha-defensin, and the complementary roles of culture techniques, histopathology, and molecular assays. Medical and surgical treatment strategies are outlined, including debridement with implant retention, one-stage and two-stage revision approaches, and organism-directed antimicrobial therapy. Preventive strategies spanning preoperative optimisation, intraoperative protocols, and postoperative risk reduction are also highlighted. Despite significant advances, important gaps persist, particularly in antimicrobial resistance, the management of polymicrobial or culture-negative infections, and the treatment of high-risk or immunocompromised patients. Continued interdisciplinary collaboration and high-quality clinical research are essential to refine diagnostic algorithms, improve therapeutic outcomes, and reduce the incidence of this increasingly consequential complication.
Background/Objectives: Drug supply disruptions represent an increasingly serious problem for health systems worldwide, with systemic antibiotics among the most frequently affected therapeutic categories. Although regulatory authorities have repeatedly signaled this risk, comparative studies analyzing patterns of antibiotic shortages across multiple countries simultaneously remain scarce. Methods: We performed a cross-sectional comparative analysis based on data from public national shortage registries in seven jurisdictions: Belgium, France, Germany, Romania, Spain, the United States (FDA), and the Kingdom of Saudi Arabia. All records corresponding to systemic antibiotics in ATC group J01 were extracted, harmonized, and analyzed, with the active substance (INN) as the unit of analysis. The association between critical drug status according to the EMA list and the multinational recurrence of shortages was assessed using chi-square tests, the Mann-Whitney U test, and multivariate logistic regression. To verify the robustness of the results, a sensitivity analysis was also performed using alternative thresholds for jurisdictions. Results: A total of 350 shortage records were mapped, corresponding to 64 unique active pharmaceutical ingredients. On average, each active substance was reported as out of stock in 3.48 jurisdictions (SD = 1.46). Macrolides (J01F) and quinolones (J01M) exhibited the widest geographic spread of shortages. Antibiotics included on the EMA's list of critical medicines were reported as missing in multiple countries simultaneously significantly more frequently than those not included on this list (82.86% vs. 37.14%; χ2 = 71.99, p < 0.001; Cramer's V = 0.454). In the multivariate logistic regression model, EMA critical medicine status remained an independent predictor of multinational recurrence of shortages (OR = 8.29; 95% CI: 4.93-13.94; p < 0.001), while the injectable route of administration did not reach the threshold for statistical significance (OR = 0.78; p = 0.341). Sensitivity analysis confirmed that this association remains statistically significant regardless of the threshold chosen. Conclusions: Shortages of systemic antibiotics tend to occur simultaneously in multiple countries, and drugs designated as critical by the EMA are disproportionately affected. The results suggest that the identified weaknesses are not specific to a single health system but reflect structural fragilities in international antibiotic supply chains. This underscores the need for internationally coordinated strategies, both for monitoring the availability of essential antibiotics and for preventing and managing shortages.
Background/Objectives: Mycobacterium avium subsp. hominissuis is a cause of disseminated infections in immunosuppressed patients and pulmonary infections in individuals with chronic lung conditions. The treatment of this infection is prolonged, and ultimately associated with failure in a large percentage of patients. Previous studies have determined that the bacteria respond to antibiotic contact, altering pathways affecting metabolic and other functions, as well as structural aspects. Methods: Based on this assumption and the fact that the medication used to treat M. avium infection may encounter the target bacterium at different sequential times, we evaluated the effect of three antibiotics, clarithromycin, ethambutol and rifabutin, delivered together or separately in different orders. Results: The results showed no difference regarding the response of the bacterium to treatment with the three antibiotics when in planktonic state. However, in either the biofilm phenotype or inside macrophages, different orders of exposure to antibiotics led to different responses. In macrophages, the sequence of exposure when ethambutol was given first, followed by clarithromycin and rifabutin, was associated with bacterial count decrease, similar to the simultaneous exposure to the three antibiotics, whereas the other combinations showed a decreased effect. Conclusions: In summary, the study highlights an important aspect of bacterial response to combination therapies, and more specifically, the response of M. avium to therapy. The use of a cell wall-active antibiotic first appears to be linked to an improvement in therapy efficacy.
Background/Objectives: Given the ongoing threat of antimicrobial resistance, the identification and characterization of multidrug-resistant isolates are essential. An increase in antimicrobial-resistant bacteria has been reported in Romania, but national data are still scarce. This study aimed to evaluate beta-lactamase-producing Gram-negative bacteria (GNB) isolated over two years at a Romanian nephrology hospital, while comparing carbapenemase detection phenotypic methods. Methods: Gram-negative bacterial isolates collected between January 2022 and May 2024 that met antimicrobial resistance screening criteria were evaluated. After identification, extensive disk diffusion antibiograms were performed, read, and interpreted, complemented by testing on cloxacillin/oxacillin-supplemented Mueller-Hinton agar. The colistin minimum inhibitory concentration (MIC) was not assessed, and aztreonam-avibactam was not tested for Enterobacterales. For non-fermenter GNB, the colistin MIC was determined. Phenotypic carbapenemase production tests were performed for all strains (BlueCarba Test, CIM, mCIM, zCIM, and rCIM). Carbapenemase detection immunochromatographic tests were performed for a set of strains. Results: Among the 397 evaluated strains, 335 (84.38%) were Enterobacterales and 62 (15.62%) non-fermenter GNB, showing high antimicrobial resistance levels. Of these, 188 (47.35%) were Klebsiella pneumoniae; 139/188 (73.93%) showed carbapenem resistance and carbapenemase production; 49/188 (26.06%) produced two carbapenemases; and 45/188 (23.93%) presented resistance to all tested antimicrobials. MALDI-TOF identified 28 KPC-producing K. pneumoniae strains. Lateral flow assays revealed NDM, VIM, KPC, and OXA-48-like enzymes in 48 of 56 tested Enterobacterales; 12/48 strains produced two carbapenemases. Of the 62 non-fermenter GNB, 33 were Pseudomonas spp. and 20 Acinetobacter baumannii; one Pseudomonas spp. was susceptible only to colistin and seven only to cefiderocol; four A. baumannii were susceptible only to colistin and three only to cefiderocol. Lateral flow assays detected VIM or IMP enzymes in 13/33 Pseudomonas spp. and OXA-23 and/or OXA-40/-58 enzymes in all 20 A. baumannii. Conclusions: Among the evaluated strains, many showed resistance to multiple antimicrobial classes. Furthermore, strains co-producing two carbapenemases were identified.
Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a critical public health threat because infections caused by this pathogen are associated with high morbidity, mortality, and limited effective therapeutic options. Whilst the majority of studies have concentrated on inter-patient bacterial transmission, within-host genomic analysis offers unprecedented resolution for tracking dynamic clone predominance, plasmid rearrangements, and microevolution under clinical selection pressures. Methods and Results: Whole-genome sequencing (WGS) of nine isolates recovered from oral and rectal swabs revealed an exceptional case of CRKP clonal turnover in an intensive care unit (ICU) patient. Three distinct high-risk clones were identified during the 18 days of surveillance: an initial ST101 (Clonal Group (CG) 101) strain (days 1-7) followed by concurrent colonization with ST395 (carrying blaNDM-5) and ST512 lineages (both CG258, days 11-18). Conclusions: This study describes a rare instance of within-host heterogeneity of CRKP, involving three distinct STs spanning two CGs. Whole-genome analysis revealed potential structural rearrangements of resistance- and virulence-associated plasmids between coexisting lineages. These genomic shifts likely reflect rapid adaptation under the intense selective pressure of broad-spectrum antibiotic therapy, culminating in the persistence of a less virulent yet multidrug-resistant ST512 clone and a favorable clinical outcome with patient recovery.
Salmonella remains one of the most critical zoonotic pathogens in the poultry sector, linked to animal disease, foodborne illness, and the global crisis of antimicrobial resistance (AMR). Poultry acts as a major reservoir, enabling Salmonella transmission from hatchery to retail products through horizontal, vertical, and environmental routes. Despite the use of biosecurity, vaccination, antibiotics, and chemical decontamination, effective and sustainable control across the poultry value chain remains difficult, particularly in the face of rising multidrug-resistant strains and growing consumer concerns over chemical residues. Bacteriophages (phages), viruses that selectively infect and lyse bacteria, have emerged as a promising biological alternative for Salmonella control. Although many studies have reported the effectiveness of phages against bacterial species, including Salmonella, in the poultry industry, reports on their full potential to combat antimicrobial-resistant Salmonella across the entire poultry value chain remain limited. Therefore, this review synthesizes current evidence on the application of phages throughout the poultry value chain, including on-farm interventions, processing plant decontamination, and food packaging and storage. Findings from the reviewed articles indicate over a 90% reduction in Salmonella spp. in poultry farms and post-harvest meat, along with lower mortality in phage-treated groups compared to untreated groups; however, these outcomes depend on several factors (e.g., phage strains, concentrations, application methods, and environmental conditions). Laboratory, pilot, and field studies consistently demonstrate that phage preparations, especially when formulated as cocktails or combined with complementary interventions, can achieve substantial reductions in Salmonella, including antibiotic-resistant serovars, in live birds, eggs, poultry environments, and meat products. Unlike antibiotics and chemical sanitizers, phages act with high specificity, preserving beneficial microbiota and maintaining the sensory and nutritional quality of poultry products. Their safety has been supported by toxicological and genomic assessments, and several phage-based products have obtained regulatory approval, including Generally Recognized as Safe (GRAS) status for food applications in the United States. By integrating efficacy, safety, regulatory, and practical deployment data, this review highlights bacteriophages as a scientifically validated and One Health-aligned tool capable of reducing Salmonella transmission from farm to fork across the poultry value chain, thereby laying the foundation for their future adoption in the poultry industry. Phage-based interventions offer a sustainable pathway to enhance food safety, limit antimicrobial resistance (AMR) dissemination, and strengthen consumer confidence in poultry products. However, the major limitation is the emergence of phage-resistant bacterial strains, as well as the potential involvement of some phages in the transfer of resistance and virulence genes, which could raise public concern. Nevertheless, the use of phage cocktails and whole-genome sequencing, involving tools such as ResFinder and virulence finder, can facilitate the selection of safe phages for application.
Background/Objectives:Acinetobacter baumannii is a major cause of hospital-acquired and ventilator-associated pneumonia and is associated with high mortality among critically ill patients. Although antimicrobial resistance remains a major therapeutic challenge, the relative contribution of clinical severity, organ dysfunction, and laboratory parameters to patient outcomes requires further clarification. Methods: We conducted a retrospective single-center cohort study including 165 patients with microbiologically confirmed A. baumannii pneumonia admitted to the Clinical Hospital of Pneumology Iași, Romania, between 2019 and 2025. Clinical, laboratory, and outcome data were analyzed, and multivariable logistic regression was performed to identify independent predictors of in-hospital mortality. Results: In-hospital mortality was independently associated with older age (OR: 1.05 per year, 95% CI: 1.01-1.08, p = 0.005), sepsis (OR: 5.23, 95% CI: 1.93-16.5, p = 0.002), and mechanical ventilation (OR: 6.71, 95% CI: 3.02-15.6, p < 0.001). In exploratory analyses restricted to patients with available lactate measurements, lactate levels were not significantly associated with mortality, whereas acute kidney injury and dynamic renal deterioration were associated with increased mortality. Inflammatory markers, particularly neutrophil-to-lymphocyte ratio and C-reactive protein at 72 h, were significantly higher in non-survivors. Conclusions: These findings suggest that mortality in A. baumannii pneumonia is more closely associated with clinical severity, sepsis, respiratory failure, and evolving organ dysfunction than with isolated laboratory parameters. Early recognition of sepsis, acute kidney injury, and respiratory failure, together with serial assessment of inflammatory biomarkers, may support improved risk stratification in this high-risk population.
Background: Pneumonia is a common cause of hospitalization and a significant contributor to worldwide morbidity and mortality. Effective definitive antimicrobial therapy for pneumonia relies on accurate identification of bacterial pathogens and their resistance patterns. Therefore, this study aims to evaluate the distribution bacterial pathogens and their antimicrobial resistance patterns, as well as clinical factors associated with outcomes among hospitalized pneumonia patients. Methods: This retrospective cohort study was conducted at Dr. Hasan Sadikin General Hospital, Indonesia, and included adult patients hospitalized with pneumonia between January and December 2024. Clinical, demographic, microbiological, and outcome data were extracted from electronic medical records and the laboratory system. Bacterial distribution, antimicrobial patterns, and clinical outcomes were analyzed descriptively and compared across pneumonia types. Multivariable regression analyses were performed to identify factors associated with in-hospital mortality and length of hospital stay. Results: A total of 662 hospitalized pneumonia patients were included with Gram-negative bacteria (i.e., Klebsiella pneumonia, Acinetobacter baumannii, and Pseudomonas aeruginosa) identified as the most common pathogens. Carbapenem-resistant Acinetobacter baumannii (CR-Ab) and Klebsiella pneumoniae (CR-Kp) were the most frequently identified resistant pathogens, particularly in hospital-acquired (HAP) and ventilator-associated pneumonia (VAP). HAP and VAP were independently associated with higher in-hospital mortality and longer hospital stay compared to community-acquired pneumonia (CAP). In addition, CR-Ab and difficult-to-treat Pseudomonas aeruginosa (DTR-Psa) were associated with prolonged hospitalization. Conclusions: Type of pneumonia, bacterial pathogens and resistance patterns were associated with in-hospital mortality and length of hospital stay. These findings highlight the importance of ongoing microbiological surveillance, antimicrobial stewardship, and infection prevention strategies to optimize pneumonia management and clinical outcomes.
Background/Objectives: Rabbit farming in Romania is increasingly important for providing high-quality meat, yet productivity is frequently threatened by enteric diseases, particularly in young animals. Among bacterial etiologies, Clostridioides difficile (C. difficile) has emerged as a significant gastrointestinal pathogen, with findings suggestive of systemic dissemination and public health implications. This study aimed to investigate a fatal case of C. difficile infection in a farmed rabbit and to characterize the pathogen’s microbiological, toxigenic, and antimicrobial profile. Methods: An 11-month-old male German Giant Spotted rabbit presenting acute diarrhea, anorexia, and rapid deterioration after unsupervised administration of enrofloxacin and sulfaquinoxaline was submitted postmortem. Necropsy was performed, and samples from cecum, colon, liver, spleen, mesenteric lymph nodes, lungs, and femoral bone marrow were collected. Microbiological analysis included selective culture on CCFA medium, ELISA for toxin A and B detection, MALDI-TOF MS identification, PCR confirmation, and antimicrobial susceptibility testing with the VITEK 2 system. Histopathological examination was conducted on intestinal and parenchymal tissues. Results: Necropsy revealed severe congestion and necrosis of the cecal and colonic mucosa, hepatomegaly, splenic congestion, and petechial hemorrhages. C. difficile was isolated from intestinal sites, confirmed as toxigenic by ELISA and PCR. Histopathology showed necrotizing colitis with epithelial desquamation, fibrin deposition, and heterophilic infiltration. The strain exhibited resistance to clindamycin, ampicillin, and tetracycline, with susceptibility to vancomycin, linezolid, and tigecycline. Conclusions: This case demonstrates that C. difficile can cause severe disease in rabbits, particularly following antimicrobial-induced dysbiosis. The findings underscore the importance of prudent antibiotic use, monitoring of toxigenic strains in rabbit populations, and implementation of preventive strategies to mitigate health risks in both animals and potentially humans.
BACKGROUND/OBJECTIVES:Escherichia coli is the predominant pathogen in community-onset urinary tract infections (UTIs) requiring hospitalization. This study characterized antimicrobial resistance profiles, biofilm formation, extended-spectrum β-lactamase (ESBL) gene distribution, and phylogenetic background of E. coli isolates from hospitalized UTI patients in Western Mexico. METHODS:Seventy isolates (September 2023-September 2024) underwent susceptibility testing (CLSI M100, 35th edition), multiplex PCR for blaTEM, blaCTX-M, and blaSHV genes, crystal violet biofilm quantification, and Clermont quadruplex PCR phylotyping. Associations were evaluated by Fisher's exact test with Benjamini-Hochberg FDR (BH-FDR) correction. RESULTS:ESBL phenotype and MDR were detected in 57.1% and 58.6% of isolates. After BH-FDR correction, ESBL production was significantly associated with amikacin (OR = 5.55; 95% CI: 1.80-18.74; q = 0.002) and TMP-SMX non-susceptibility (OR = 3.00; 95% CI: 1.02-9.23; q = 0.036); ciprofloxacin non-susceptibility was linked to MDR status (OR = 7.21; 95% CI: 1.28-75.66; q = 0.017) but not ESBL phenotype. Biofilm was detected in 77.1% of isolates. blaTEM predominated among ESBL producers (85.0%). Phylogroup B2 (51.4%) was inversely associated with recurrent UTI on both univariate (OR = 0.17; 95% CI: 0.03-0.73; p = 0.008) and adjusted analysis (adjusted OR = 0.19; 95% CI: 0.05-0.81; p = 0.025). Phylogroup C (22.9%) exhibited the highest MDR prevalence (81.3%) and the highest biofilm formation rate among phylogroups (87.5%). CONCLUSIONS:The high prevalence of ESBL-producing and MDR E. coli, combined with an unexpected predominance of blaTEM, reveals a distinctive local resistance landscape diverging from regional trends. The inverse association of phylogroup B2 with recurrence and TMP-SMX resistance reinforces the clinical value of phylogenetic surveillance in guiding UTI management strategies.
Antimicrobial resistance (AMR) constitutes a critical and escalating global public health challenge, severely limiting the potential of existing antimicrobial drugs and escalating infection-associated morbidity and mortality rates. This analysis focuses on the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species), which are prioritized by the World Health Organization (WHO) and represent a significant cause of nosocomial infections due to their extensive drug resistance. We provide an in-depth review of the global prevalence and specific antibiotic-resistant mechanisms of these pathogens. Due to the decline in the traditional antibiotic development pipeline, accelerated development of alternative therapeutic strategies is essential. The review comprehensively discusses innovative non-traditional therapies currently being explored to bypass traditional antibiotic limitations, such as phage therapy, antimicrobial peptides (AMPs), anti-virulence therapies, fecal microbiota transplantation (FMT), and targeted CRISPR-based approaches. Addressing the ESKAPE challenge requires a concerted, multi-sectoral strategy guided by the One Health principle, focusing on enhancing public awareness, improving surveillance and research, optimizing judicious antibiotic use, and cultivating sustainable investment in novel interventions.
