Antimicrobial resistance (AMR) has emerged as a major threat to public health globally. Accurate and rapid detection of resistance to antimicrobial drugs, and subsequent appropriate antimicrobial treatment, combined with antimicrobial stewardship, are essential for controlling the emergence and spread of AMR. This article reviews common antimicrobial susceptibility testing (AST) methods and relevant issues concerning the advantages and disadvantages of each method. Although accurate, classic technologies used in clinical microbiology to profile antimicrobial susceptibility are time-consuming and relatively expensive. As a result, physicians often prescribe empirical antimicrobial therapies and broad-spectrum antibiotics. Although recently developed AST systems have shown advantages over traditional methods in terms of testing speed and the potential for providing a deeper insight into resistance mechanisms, extensive validation is required to translate these methodologies to clinical practice. With a continuous increase in antimicrobial resistance, additional efforts are needed to develop innovative, rapid, accurate, and portable diagnostic tools for AST. The wide implementation of novel devices would enable the identification of the optimal treatment approaches and the surveillance of antibiotic resistance in health, agriculture, and the environment, allowing monitoring and better tackling the emergence of AMR.

Background/Objectives: Antimicrobial resistance poses a major public health challenge. The World Health Organization has identified 15 priority pathogens that require prompt development of new antibiotics. This review systematically evaluates the antibacterial resistance of the most significant bacterial pathogens, currently available treatment options, as well as complementary approaches for the management of infections caused by the most challenging multidrug-resistant (MDR) bacteria. For carbapenem-resistant Gram-negative bacteria, treatment options include combinations of beta-lactam antibiotics and beta-lactamase inhibitors, a novel siderophore cephalosporin, known as cefiderocol, as well as older antibiotics like polymixins and tigecycline. Treatment options for Gram-positive bacteria are vancomycin, daptomycin, linezolid, etc. Although the development of new antibiotics has stagnated, various agents with antibacterial properties are currently in clinical and preclinical trials. Non-antibiotic strategies encompass antibiotic potentiators, bacteriophage therapy, antivirulence therapeutics, antimicrobial peptides, antibacterial nanomaterials, host-directed therapy, vaccines, antibodies, plant-based products, repurposed drugs, as well as their combinations, including those used alongside antibiotics. Significant challenges exist in developing new antimicrobials, particularly related to scientific and technical issues, along with policy and economic factors. Currently, most of the alternative options are not part of routine treatment protocols. Conclusions and Future Directions: There is an urgent need to expedite the development of new strategies for treating infections caused by MDR bacteria. This requires a multidisciplinary approach that involves collaboration across research, healthcare, and regulatory bodies. Suggested approaches are crucial for addressing this challenge and should be backed by rational antibiotic use, enhanced infection control practices, and improved surveillance systems for emerging pathogens.

This study aimed to investigate the chemical composition of steam distillate essential oil and corresponding hydrolate obtained from S. officinalis grown in Serbia, as well as the influence of weather conditions (temperature and precipitations) on their chemical profiles. Furthermore, their antimicrobial activity was investigated in vitro. The main compounds in essential oil were cis-thujone, followed by camphor, trans-thujone, and 1,8-cineole, while hydrolate was slightly different from the essential oil, with camphor, cis-thujone, and 1,8-cineole as the main compounds. Among the eight respiratory-associated microorganisms, Klebsiella oxytoca was the most sensitive to the tested EOs (minimum inhibitory concentration (MIC)/minimal bactericidal/fungicidal concentration (MBC/MFC) were 14.20 and 28.4 μL mL⁻¹, respectively). MIC and MBC values of other tested bacteria ranged between 28.40 and 227.25 μL mL⁻¹ while for Candida albicans MIC/MFC ranged from 28.40/56.81 to 56.81–113.63 μL mL⁻¹. Antibiotic susceptibility patterns for the analyzed eight respiratory-associated microorganisms showed an intermediate level of resistance to commonly used antibiotics such as ampicillin, levofloxacin, and ciprofloxacin. As a preliminary approach to the antimicrobial profiling of the tested EO, the obtained results revealed that the tested samples possess remarkable antibacterial activities and could be used to develop pharmaceutical formulations as an alternative to conventional antibiotic therapy.

Background/Objectives: Community-acquired pneumonia (CAP) is a major cause of hospitalization and mortality worldwide, with growing interest in adjunctive therapies to enhance treatment outcomes. Donkey milk, long used in traditional medicine for respiratory illnesses, contains bioactive compounds with antimicrobial, anti-inflammatory, and immunomodulatory properties that may benefit patients with CAP. Methods: Sixty hospitalized patients were prospectively allocated into two groups based on their consent to receive adjunctive donkey milk supplementation: one received standard antibiotic therapy plus 250 mL of pasteurized donkey milk twice daily for one month, while the control group received antibiotics alone. Results: Patients consuming donkey milk showed significantly faster reductions in C-reactive protein CRP and procalcitonin PCT levels, greater radiological improvement (p < 0.001), and a shorter average hospital stay (12.46 vs. 14.16 days). Logistic regression analysis identified donkey milk consumption as a significant predictor of shorter hospital stay. Importantly, no adverse effects were reported, and compliance with the supplementation was high. Conclusions: These findings suggest that pasteurized donkey milk may serve as a safe and effective natural adjunct to standard antibiotic therapy in managing CAP, with potential to enhance recovery and reduce hospital stay. Further large-scale studies are needed to validate these results and explore broader applications of donkey milk in infectious diseases.

Background: Eikenella corrodens, a member of the HACEK group, is a fastidious Gram-negative bacillus that is part of the normal oropharyngeal microbiota and rarely causes lower respiratory tract infections. Pulmonary infections caused by E. corrodens are typically associated with predisposing factors such as aspiration, mucosal injury, or airway obstruction. Case Presentation: We report the case of a 79-year-old woman without known immunosuppressive conditions who presented with a several-week history of productive cough and progressive respiratory symptoms. The initial clinical evaluation and chest radiography findings were nonspecific. Subsequent chest computed tomography (CT) revealed left lower lobe consolidation and bilateral apical bronchiolitis. Flexible bronchoscopy revealed a whitish-yellow, plant-derived endobronchial foreign body causing near-complete obstruction of the basal segmental bronchus with purulent secretions distally. Following bronchoscopic removal, a bronchial aspirate collected immediately after extraction yielded E. corrodens in pure culture (> 10⁵ CFU/mL), supporting true lower respiratory infection rather than contamination. Histopathological examination confirmed the presence of organic foreign material. The isolate was susceptible to all tested beta-lactams, fluoroquinolones, tetracycline, and co-trimoxazole, and resistant to azithromycin. Susceptibility-guided therapy based on susceptibility testing resulted in clinical and radiological improvement. Conclusion: This case highlights the diagnostic value of bronchoscopy in persistent focal pneumonia and underscores that isolation of E. corrodens in pure culture from appropriately collected lower respiratory specimens should prompt careful evaluation for aspiration or airway obstruction.

Antimicrobial resistance (AMR) is a major global health challenge affecting human and animal health, food safety, and the effectiveness of antimicrobial therapy. Therefore, this study evaluated the antimicrobial activity of raw (RDM) and pasteurized donkey milk (PDM) against clinically relevant Gram-negative bacteria with different AMR profiles. Antimicrobial activity against ten clinical Enterobacterales isolates, including CTX-M-, OXA-48-, KPC-, NDM-, and VIM-producing strains, was assessed by monitoring bacterial growth kinetics in artificially contaminated milk samples during 8 h of incubation at 37 °C. Pasteurized cow milk (CM) and nutrient broth (NB) served as controls. The strongest antimicrobial effects were observed against OXA-48-producing Klebsiella pneumoniae A4 and CTX-M-producing Escherichia coli A1, whereas Citrobacter koseri F5 showed the lowest susceptibility. After 8 h, K. pneumoniae A4 counts remained below 2 log CFU/mL in RDM compared with >6 log CFU/mL in NB. Significant effects of milk type, incubation time, and their interaction on bacterial growth were confirmed (p < 0.001). Donkey milk significantly inhibited bacterial growth compared with NB and CM, while some differences between RDM and PDM were observed depending on the bacterial isolate. These findings support donkey milk as a bioactive matrix with potential antimicrobial applications.