Antimicrobial peptides (AMPs) are short protein fragments that function as an innate immune response across diverse life forms. Structurally, AMPs exhibit diverse configurations, including α-helical, β-sheet, mixed, and random-coil forms, enabling a variety of mechanisms to combat pathogens. The mechanisms of action of AMPs encompass membrane disruption and inhibition of critical cellular processes, highlighting their broad-spectrum activity against bacteria, fungi, viruses, and parasites. AMP activity extends to anti-tumor and anti-HIV activities, further emphasizing their therapeutic potential. Purifying AMPs from natural sources can be challenging due to posttranslational processing. Fortunately, chemical synthesis has the advantage of producing high yield and pure AMPs, but the reaction efficiency diminishes as the molecular weight of peptides increases. Advances in computational tools and curated databases have further accelerated AMP discovery and engineering. While commercially available AMP-based antibiotics and in vivo efficacy against multidrug-resistant bacteria demonstrate their clinical relevance, several limitations still hinder the widespread use of AMPs such as low stability and toxicity to human cells. This review provides a comprehensive overview of AMP origins, characteristics, mechanisms, applications, and future prospects in combating infectious diseases with a particular focus on the clinical applicability of AMPs and their prospects as potent alternative to traditional antibiotics.

Acinetobacter baumannii is pathogen of global concern. It causes infection, especially among immunocompromised individuals in intensive care units, due to its ability to survive for long periods on hard surfaces and under a wide range of environmental conditions and become resistant to almost all the available antibiotics used in clinical practice. Objectives: This study aims to address the gap in A. baumannii surveillance in Saudi Arabia by tracking the prevalence, patterns, and trends of acquired A. baumannii resistance at a healthcare facility in the western part of Saudi Arabia over eleven years. Methods: The study was conducted in a tertiary care hospital in the western region of Saudi Arabia, from January 2013 to December 2023. Results: Our data indicated that A. baumannii infections were predominantly observed in inpatients admitted to the hospital (96%) compared to those treated as outpatients in the emergency clinic (4%). The mean of annual A. baumannii infections isolated from inpatients is 503.3, whereas the mean for outpatients is 21, indicating a statistically significant difference with a p-value of <0.0001. The analysis of the antimicrobial susceptibility profile of A. baumannii demonstrated a variable levels of resistance to the evaluated antibiotics. The lowest resistance rate was for colistin. Conclusions: In conclusion, the incidence patterns of A. baumannii isolates peaked in 2013, then declined, and have recently shown an increase, underscoring the necessity for proactive interventions to curtail its dissemination, notwithstanding initial decreases in infection rates and resistance.

Background: The growing resistance seen in various antibiotics, including those considered as last-resort options, underscores the pressing need for novel approaches and new substances to address MRSA infections. Combining antibiotics as a treatment approach can enhance effectiveness, expand the range of targeted bacteria, and minimize the likelihood of resistance emergence. This approach holds promise in addressing the escalating issue of antibiotic resistance. Purpose: This study seeks to investigate the potential synergy between 3-hydrazinoquinoxaline-2-thiol and penicillin against a diverse array of MRSA isolates, thereby providing insights into their combined antimicrobial action. Methods: Twenty-two clinical MRSA isolates subjected to broth microdilution to determine the Minimum Inhibitory Concentrations (MICs) of 3-hydrazinoquinoxaline-2-thiol and penicillin. Subsequently, a checkerboard assay was employed to evaluate the interaction between 3-hydrazinoquinoxaline-2-thiol and penicillin, focusing on the Fractional Inhibitory Concentration Index (FICI). Results: The MICs of penicillin and 3-hydrazinoquinoxaline-2-thiol were determined for 22 clinical MRSA strains. Penicillin exhibited MICs within a range of 1024 to 128 μg/mL, while 3-hydrazinoquinoxaline-2-thiol displayed MICs varying from 64 to 8 μg/mL. Remarkably, the combination of 3-hydrazinoquinoxaline-2-thiol and penicillin yielded a synergistic effect, resulting in a significant reduction of MICs by up to 64-fold. Conclusion: The potential of 3-hydrazinoquinoxaline-2-thiol in combination with penicillin as a viable solution against MRSA appears promising. However, to establish its practical utility, further extensive testing and experiments are essential.

Background: Fungal infections, especially those caused have emerged as a significant medical concern over the past three decades, particularly among immunocompromised patients. However, recent studies have highlighted the increasing prevalence of fungal infections resembling yeast other than Candida, such as trichosporonosis, especially among immunosuppressed individuals worldwide. Trichosporon has been identified as a significant contributor to superficial and invasive infections. Invasive trichosporonosis, primarily affecting immunocompromised patients, poses a significant threat with high mortality rates. Purpose: The current study aimed to explore the clinical epidemiology of Trichosporon spp at King Abdulaziz University Hospital (KAUH) in Saudi Arabia. Methods: This retrospective study aimed to assess the clinical epidemiology of Trichosporon spp. infections in microbiology cultures obtained from KAUH in Saudi Arabia. The study analyzed data from patients over a five-year period, focusing on demographic, clinical, and microbiological characteristics. Results: This study encompassed 21 participants, categorized into four distinct age groups. Moreover, this study indicated T. asahii as the predominant species isolated, accounting for 90.5% of infections, followed by T. mucoides (9.5%). ICU hospitalization, diabetes mellitus, taking immunosuppressive drugs, and antifungal drugs, and the use of invasive medical equipment were identified as prominent risk factors for trichosporonosis. Urinary tract infections were the most common clinical presentation, particularly among male and elderly patients. Mortality rates were high, especially among older individuals. Conclusion: This study contributes valuable epidemiological insights into trichosporonosis, highlighting the need for enhanced surveillance and preventive strategies in healthcare settings. Further research is warranted to optimize treatment approaches and infection control measures, ultimately reducing the burden of Trichosporon infections on patient outcomes.

Background: Enterococcus faecalis and Enterococcus faecium are part of the human microbiota but pose significant risks in clinical settings due to increasing antimicrobial resistance. Vancomycin-resistant enterococci (VRE) are a growing concern, linked to high morbidity and mortality in hospitalized patients. Aim: This study is the first comprehensive investigation of VRE prevalence and associated risk factors at King Abdulaziz University Hospital (KAUH) from 2015 to 2022. Methods: Clinical samples were collected, and VRE isolates were identified using VRE Card GeneXpert, BioFire PCR, and the VITEK 2 system. Descriptive statistical analysis with Stata version 17 summarized patient characteristics, including demographics, comorbidities, hospital exposure, and laboratory findings. Categorical variables were reported as frequencies/percentages, while continuous variables were expressed as mean ± SD or median [IQR]. Results: Among 254 adult patients with VRE infections, the median age was 61 years. The most common comorbidities were diabetes, hypertension, and kidney disease. VRE infections peaked in 2021, with urine cultures being the most frequent source. Most patients had prior antibiotic exposure, particularly to vancomycin and carbapenems. Enterococcus faecium was the predominant species, with the VanA phenotype being most common. Alarmingly, 61.8% of VRE-infected patients died during the study period. Conclusion: These findings underscore the critical need for enhanced infection control measures and antimicrobial stewardship to combat VRE and improve patient outcomes.

Biofilm-associated infections pose a significant challenge in clinical settings due to their increased resistance to antibiotics and evasion of host immune responses. These infections are responsible for a large proportion of chronic and recurrent infections, leading to prolonged hospital stays, increased healthcare costs, and elevated morbidity and mortality rates. Vancomycin, a glycopeptide antibiotic, has long been a cornerstone in the treatment of infections caused by Gram-positive bacteria, particularly methicillin-resistant Staphylococcus aureus (MRSA). In addition, vancomycin-resistant Enterococcus (VRE) represents an important group of biofilm-forming pathogens, further complicating treatment strategies. However, its efficacy against biofilms remains a subject of ongoing research and debate. The ability of vancomycin to target biofilm-embedded bacteria is often hindered by multiple resistance mechanisms, including poor antibiotic penetration, metabolic adaptation of biofilm-associated cells, and the presence of persister cells. The aim of this review is to evaluate vancomycin’s antibiofilm activity by examining its mechanism of action, pharmacokinetics, effectiveness, limitations, and potential strategies to enhance its therapeutic outcomes. Several novel approaches have been explored to augment vancomycin’s antibiofilm activity, including combination therapies, adjuvant strategies, and nanotechnology-based drug delivery systems. Understanding these factors is crucial for optimizing therapeutic strategies and overcoming the persistent challenge of biofilm-related infections. This review synthesizes current evidence and highlights areas requiring further research to enhance vancomycin’s efficacy against biofilm-associated infections.