Acetic acid treatment of pseudomonal wound infections--a review

A review of advancements in antiseptics for wound care in diabetic and non-diabetic patients

Wounds affect many people and require a considerable annual cost to manage. Wound infections significantly delay the healing process, particularly in individuals with diabetes mellitus, due to impaired immunity and microvascular complications. The use of antiseptics is considered a way to reduce this problem. The study aims to assess the different antiseptic categories frequently employed in wound management, focusing on identifying and understanding their unique features. A comprehensive review of PubMed, Scopus, and EMBASE databases identified key antiseptics, including isopropyl alcohol, chlorhexidine, polyhexanide, octenidine, povidone-iodine, hypochlorous acid, silver-based products, hydrogen peroxide, triclosan, and benzalkonium chloride. These antiseptics exhibit varying efficacies and cytotoxicity profiles, necessitating tailored usage to optimize healing while preventing antimicrobial resistance. The primary indication for antiseptics is the prevention of Surgical Site Infections (SSIs), as recommended by guidelines. For diabetic foot ulcers, the strongest evidence supports the use of hypochlorous acid. There are no universal recommendations for antiseptic use; their application depends on specific circumstances. This review highlights the need for evidence-based, condition-specific antiseptic strategies to address unique patient needs effectively.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-025-01607-7.

Alternatives to Flaps and Grafts for Management of Forehead Mohs Defects

Patients have varying goals for reconstruction after Mohs micrographic surgery, and the operative plan should reflect these goals. Forehead reconstruction with immediate flaps and grafts may not always align with these goals, and alternative methods should be considered. Evidence suggests that secondary intention healing, delayed or augmented skin grafting, skin substitutes, and delayed reconstruction with tissue expansion are acceptable alternatives to standard flaps and grafts. When possible, these options should be included in shared decision-making before reconstruction.

Evaluation of the interactions of hydrazide derivatives with acetic acid and molecular modeling analysis of N-acetylated hydrazides

Acetic acid, as a weak organic acid, has a wide range of food, pharmaceutical, and industrial applications. It is also used as a green solvent, catalyst, and reagent in chemical experiments. Properties such as non-toxicity, safety, availability, and low cost have made it the preferred choice for acetylation processes. In this project, the interactions of a series of alkyl/aryl/heteroaryl hydrazides with acetic acid were investigated under reflux heating. A variety of reactions, including C- and N-acetylation, hydrolysis, and rearrangement, occurred in the presence of acetic acid. Most of the products were recrystallized in good to excellent yields under these conditions without the need for further purification. All synthesized compounds were characterized by NMR (1H and 13C), FT-IR, and CHNS analysis. In addition, a novel method was proposed for the preparation of products 2a and 2i-q. This method has the potential to be extended to similar reagents. To investigate the biological activity and drug-like properties, some in silico methods were employed on the synthesized compounds. Screening using the ChEMBL database revealed that out of 17 synthesized compounds, compounds 2b (ChEMBL93746), 2c (ChEMBL22425), and 2d (ChEMBL441343) exhibited significant activity against targets SIRT1, TPMT, and Tyrosinase, with measured values below 200 μM. Molecular docking demonstrated that compound 2o interacted with all three targets. These findings provide valuable insights into its potential as a promising multi-target drug candidate for future investigations.

Sub-Micrometer Polycaprolactone and Polyethylene Glycol-Based Fiber Mats With Iodine and Its Potential for Wound Healing

This study introduces an innovative approach to developing advanced antimicrobial wound dressings by engineering fiber mats of polycaprolactone (PCL) and polycaprolactone/polyethylene glycol (PCL/PEG) loaded with iodine using solution blow spinning (SBS). The mats exhibited a unique morphology, combining fibers and beads, with average fiber diameters of 570 nm for 12% (w/v) PCL and 470 nm for 1% (w/v) PEG in 12% (w/v) PCL, and bead diameters of 11.34 μm and 10.43 μm, respectively. PEG incorporation rendered the mats hydrophilic and significantly enhanced their swelling capacity, which is essential for wound exudate management. Remarkably, iodine was incorporated at a concentration specifically optimized to achieve its minimum inhibitory concentration (MIC) against a range of microorganisms while preserving the structural integrity and release profile of the mats. While PEG facilitated a higher initial iodine release rate, equilibrium was achieved after 5 days. UV-Vis spectroscopy unveiled the formation of transient iodine complexes with both PCL and PEG, underscoring their functional synergy. Biological assays revealed that PCL/PEG mats loaded with 4.26 mg/mL of iodine (PCL/PEG 3MIC) exhibited potent antimicrobial efficacy against gram-positive and gram-negative bacteria, as well as fungi, alongside significant in vitro wound healing potential. These findings underscore the promise of PCL/PEG iodine-loaded mats as an innovative platform for next-generation antimicrobial wound care, combining effective infection control with enhanced wound healing capabilities.

Immunoresponsive gene 1 facilitates TLR4 agonist-induced augmentation of innate antimicrobial immunity

Treatment with the toll-like receptor 4 agonist monophosphoryl lipid A conditions innate immunocytes to respond robustly to subsequent infection, a phenotype termed innate immune memory. Our published studies show that metabolic reprogramming of macrophages is a prominent feature of the memory phenotype. We undertook studies to define the functional contributions of tricarboxylic acid cycle reprogramming to innate immune memory. We observed that priming of wild-type mice with monophosphoryl lipid A potently facilitated accumulation of the tricarboxylic acid cycle metabolite itaconate at sites of infection and enhanced microbial clearance. Augmentation of itaconate accumulation and microbial clearance was ablated in Irg1-deficient mice. We further observed that monophosphoryl lipid A potently induces expression of Irg1 and accumulation of itaconate in macrophages. Compared to wild-type macrophages, the ability of Irg1-deficient macrophages to kill Pseudomonas aeruginosa was impaired. We further observed that itaconate is directly antimicrobial against P. aeruginosa at pH 5, which is characteristic of the phagolysosome, and is facilitated by reactive oxygen species. Monophosphoryl lipid A-induced augmentation of glycolysis, oxidative phosphorylation, and accumulation of the tricarboxylic acid cycle metabolites succinate and malate was decreased in Irg1 knockout macrophages compared to wild-type controls. RNA sequencing revealed suppressed transcription of genes associated with phagolysosome function and increased expression of genes associated with cytokine production and chemotaxis in Irg1-deficient macrophages. This study identifies a contribution of itaconate to monophosphoryl lipid A-induced augmentation of innate antimicrobial immunity via facilitation of microbial killing as well as impact on metabolic and transcriptional adaptations.

The efficacy and safety of acids as topical antimicrobial agents: a review

OBJECTIVE

Infected wounds, refractory to conventional therapy, are a major burden on the healthcare system. Available data show that many commonly used antiseptic agents may be toxic to the cells involved in the healing process and may affect the normal tissue repair. The topical use of different acids to control wound infections effectively and promote healing is well known. The present review aims to summarise the safety and efficacy of various acids as topical agents for treating wound infections.

METHOD

A literature search was performed in PubMed and manually from other sources (cross references and journal sites).

RESULTS

We reviewed 116 articles, from which data from 86 relevant articles were analysed. The studies showed that various organic acids were clinically effective in treating wound infections.

CONCLUSION

This study found that various organic acids can act as a substitute for antiseptics to control wound infections refractory to conventional antibiotic therapy and local wound care. Various organic acids differ in efficacy, safety and limitations as topical agents to control wound infections and promote healing. Some acids deliver better results than others, particularly in those cases in which antibiotics and routine antiseptic agents yield little lasting success, especially in controlling hospital strains with multiple antibiotic resistance. Among topically used acids, citric acid and acetic acid are associated with better results.

The Acid-Buffered Engineered Gel Promotes In Vitro Cutaneous Healing and Fights Resistant Bacteria in Wounds

Background: Treatment of cutaneous wound infections is becoming a major clinical challenge due to the growing problem of antimicrobial resistance associated with existing wound treatments. Two prevalent pathogens in wound infections, Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa), continue to present a serious challenge, underscoring the critical need for new therapeutic alternatives. Methods: Novel alginate acid-buffered gels (ABF-1, ABF-2, and ABF-3) were developed using a combination of organic acids in various concentrations and buffered at a pH of 4.5. The acid-buffering capacity of the gels was evaluated against sodium hydroxide solution and simulated wound fluid (SWF) at different wound pHs, mimicking infected and non-infected wound environments. The in vitro antibacterial activity was assessed against resistant bacterial strains (Gram-positive and Gram-negative) using a microdilution method and wound biofilm assay. The rheological properties and cell viability of the gels were evaluated and the gel showing positive cell viability was further investigated for healing ability using an in vitro wound scratch assay. Results: The gels showed promising in vitro antibacterial activity against Staphylococcus epidermidis, S. aureus, and P. aeruginosa. Gels with higher acid concentrations (ABF-1 and ABF-2) were highly effective in reducing the bacterial load in chronic biofilms of S. aureus and P. aeruginosa, while the gel with a lower acid concentration (ABF-3) showed positive effects on the viability of skin cells (over 80% cells viable) and for promoting wound closure. All three gels demonstrated excellent acid-buffering capabilities. Conclusions: The acid-buffered gels demonstrate promising in vitro antibacterial effects, indicating their potential for enhancing wound healing.

Increased antimicrobial resistance of acid-adapted pathogenic Escherichia coli, and transcriptomic analysis of polymyxin-resistant strain

This study investigated the acid adaptation and antimicrobial resistance of seven pathogenic Escherichia coli strains and one commensal strain under nutrient-rich acidic conditions. After acid adaptation, three pathogenic E. coli survived during 100 h incubation in tryptic soy broth at pH 3.25. Acid-adapted (AA) strains showed increased resistance to antimicrobials including ampicillin, ciprofloxacin and especially polymyxins (colistin and polymyxin B), the last resort antimicrobial for multidrug-resistant Gram-negative bacteria. Enterotoxigenic E. coli strain (NCCP 13717) showed significantly increased resistance to acids and polymyxins. Transcriptome analysis of the AA NCCP 13717 revealed upregulation of genes related to the acid fitness island and the arn operon, which reduces lipopolysaccharide binding affinity at the polymyxin site of action. Genes such as eptA, tolC, and ompCF were also upregulated to alter the structure of the cell membrane, reducing the outer membrane permeability compared to the control, which is likely to be another mechanism for polymyxin resistance. This study highlights the emergence of antimicrobial resistance in AA pathogenic E. coli strains, particularly polymyxin resistance, and the mechanisms behind the increased antimicrobial resistance, providing important insights for the development of risk management strategies to effectively control the antimicrobial resistant foodborne pathogens.

Electrospun nanofibrous wound dressings with enhanced efficiency through carbon quantum dots and citrate incorporation

Nanofibers show promise for wound healing by facilitating active agent delivery, moisture retention, and tissue regeneration. However, selecting suitable dressings for diverse wound types and managing varying exudate levels remains challenging. This study synthesized carbon quantum dots (CQDs) from citrate salt and thiourea using a hydrothermal method. The CQDs displayed antibacterial activity against Staphylococcus aureus and Escherichia coli. A nanoscaffold comprising gelatin, chitosan, and polycaprolactone (GCP) was synthesized and enhanced with silver nanoparticle-coated CQDs (Ag-CQDs) to form GCP-Q, while citrate addition yielded GCP-QC. Multiple analytical techniques, including electron microscopy, FT-IR spectroscopy, dynamic light scattering, UV-Vis, photoluminescence, X-ray diffraction, porosity, degradability, contact angle, and histopathology assessments characterized the CQDs and nanofibers. Integration of CQDs and citrate into the GCP nanofibers increased porosity, hydrophilicity, and degradability-properties favorable for wound healing. Hematoxylin and eosin staining showed accelerated wound closure with GCP-Q and GCP-QC compared to GCP alone. Overall, GCP-Q and GCP-QC nanofibers exhibit significant potential for skin tissue engineering applications.

On the potential role of naturally occurring carboxylic organic acids as anti-infective agents: opportunities and challenges

Carboxylic organic acids are intermediates of central carbon metabolic pathways (e.g. acetic, propionic, citric, and lactic acid) long known to have potent antimicrobial potential, mainly at acidic pHs. The food industry has been leveraging those properties for years, using many of these acids as preservatives to inhibit the growth of pathogenic and/or spoilage fungal and bacterial species. A few of these molecules (the most prominent being acetic acid) have been used as antiseptics since Hippocratic medicine, mainly to treat infected wounds in patients with burns. With the growth of antibiotic therapy, the use of carboxylic acids (and other chemical antiseptics) in clinical settings lost relevance; however, with the continuous emergence of multi-antibiotic/antifungal resistant strains, the search for alternatives has intensified. This prospective article raises awareness of the potential of carboxylic acids to control infections in clinical settings, considering not only their previous exploitation in this context (which we overview) but also the positive experience of their safe use in food preservation. At a time of great concern with antimicrobial resistance and the slow arrival of new antimicrobial therapeutics to the market, further exploration of organic acids as anti-infective molecules may pave the way to more sustainable prophylactic and therapeutic approaches.

Burn Wound Care Strategies for the Battlefield and Austere Settings

Burns are commonly encountered in the battlefield environment; however, the availability of burn expertise and specialized supplies is variable. Initial burn care should remain focused on cooling the burn, preventing hypothermia, basic wound cleansing, and evacuation. Key ongoing burn wound management principles include wound debridement, accurate burn size and depth estimation, wound care, ongoing wound evaluation, and treatment of suspected Gram-negative wound infection. Operative management should be limited to urgent procedures, and definitive burn management should be performed only after evacuation to a higher level of care. Flexibility, creativity, and the ability to adapt care to the tactical environment are key to the successful management of burn injuries in battlefield and austere settings.

Phylogenetic evaluation and genotypic identification of burn-related Pseudomonas aeruginosa strains isolated from post-burn human infections during hospitalization

Cutaneous burn trauma, compromise of dermal layers and immune defense system is a physical and fiscal burden on healthcare systems. Burn-wound infections are a serious complication of thermal injury and contribute significantly to care burden. After burn-induced trauma, sepsis by Pseudomonas aeruginosa impairs patient recovery and contributes to mortality and morbidity. Past studies show positive correlation between detection of Pseudomonas species and healing-impaired traumatic wounds. Pseudomonas aeruginosa is a resilient opportunistic human pathogen and a nosocomial agent involved in pathology of healing-impaired wounds, especially in burn patients. Expansive array of virulence determinants has resulted in gentamicin- and silver-resistant P. aeruginosa outbreaks. Knowledge of molecular dynamics and phylogeny of P. aeruginosa associated with burn wounds is limited. Therefore, we conducted whole-genome sequencing for genotyping and phylogenetic analysis of P. aeruginosa burn-associated strains (n = 19) isolated from 7 burn cases during hospitalization. Comparison of genetic features in P. aeruginosa strains in the core genome and mobilome detected genetic variations within some clonal infections over time. Genetic variations were observed among different burn cases, with some features identified in severe lung infections. Polyclonal infections were also observed, with differing genotypes and virulence potentials, highlighting the importance of reasoned sampling of isolates for clinical testing.

An objective comparative study of non-surgical cleansing techniques and cleanser types in bacterial burden management

Cleansing is a vital component of effective wound hygiene and biofilm management, often accomplished through vigorous mechanical action or through soaking with moistened gauze. In the present study, a quantitative comparison of the effectiveness of different cleansing techniques and solutions in removing bacteria was conducted on 71 chronic wounds using bacterial fluorescence imaging as a real-time diagnostic for moderate to high bacterial loads. Vigorous gauze cleansing for 30 s proved most effective by reducing bacterial fluorescence by 33.99%, surpassing 10-min soaking in bacterial reduction (13.24%). Among different cleansers, no statistically significant differences in effectiveness were observed, but povidone-iodine showed the strongest trend towards bacterial reduction. Sub-analysis highlighted the superiority of antiseptic cleansers over saline and gentle soap (-33.30% vs. -1.80% bacterial reduction respectively). Five percent acetic acid was also shown to be more effective in removing specific bacterial strains (Pseudomonas aeruginosa). Findings from studies like this contribute to refining wound hygiene guidelines and clinical algorithms for bacterial and biofilm management.

Biofilm therapy for chronic wounds

Chronic wounds have been a major factor of serious harm to global public health. At present, it is known that almost all chronic wounds contain biofilms, which seriously hinder the healing process. Removal of biofilms can effectively promote the healing of chronic wounds. As the study of wound biofilms deepens, many new treatment methods have emerged, thus bringing revolutionary means for the treatment of chronic wound biofilm. This review summarizes various methods for the treatment of chronic wound biofilm worldwide to provide a theoretical summary and practical basis for the selection of suitable wound biofilm treatment methods in clinical practice.

Polymer-Based Functional Materials Loaded with Metal-Based Nanoparticles as Potential Scaffolds for the Management of Infected Wounds

Wound infection due to bacterial invasion at the wound site is one of the primary challenges associated with delayed wound healing. Microorganisms tend to form biofilms that protect them from harm, leading to their multidrug resistance. The alarming increase in antibiotic resistance poses a threat to wound healing. Hence, the urgent need for novel wound dressing materials capable of managing bacterial infection is crucial for expediting wound recovery. There is considerable interest in polymeric wound dressings embedded with bioactive substances, such as metal-based nanoparticles, as potential solutions for treating microbially infected wounds. Metal-based nanoparticles have been widely used for the management of infected wounds due to their broad antimicrobial efficacy. This review focuses on polymer-based and bioactive wound dressings loaded with metal-based nanoparticles like silver, gold, magnesium oxide, or zinc oxide. When compared, zinc oxide-loaded dressings exhibited higher antibacterial activity against Gram-positive strains and silver nanoparticle-loaded dressings against gram-negative strains. However, wound dressings infused with both nanoparticles displayed a synergistic effect against both strains of bacteria. Furthermore, these dressings displayed antibiofilm activity and the generation of reactive oxygen species while accelerating wound closure both in vitro and in vivo.

Exploitation of microbial activities at low pH to enhance planetary health

Awareness is growing that human health cannot be considered in isolation but is inextricably woven with the health of the environment in which we live. It is, however, under-recognized that the sustainability of human activities strongly relies on preserving the equilibrium of the microbial communities living in/on/around us. Microbial metabolic activities are instrumental for production, functionalization, processing, and preservation of food. For circular economy, microbial metabolism would be exploited to produce building blocks for the chemical industry, to achieve effective crop protection, agri-food waste revalorization, or biofuel production, as well as in bioremediation and bioaugmentation of contaminated areas. Low pH is undoubtedly a key physical-chemical parameter that needs to be considered for exploiting the powerful microbial metabolic arsenal. Deviation from optimal pH conditions has profound effects on shaping the microbial communities responsible for carrying out essential processes. Furthermore, novel strategies to combat contaminations and infections by pathogens rely on microbial-derived acidic molecules that suppress/inhibit their growth. Herein, we present the state-of-the-art of the knowledge on the impact of acidic pH in many applied areas and how this knowledge can guide us to use the immense arsenal of microbial metabolic activities for their more impactful exploitation in a Planetary Health perspective.

The Antimicrobial Efficacy of Topically Applied Mafenide Acetate, Citric Acid and Wound Irrigation Solutions Lavanox and Prontosan against Pseudomonas aeruginosa

Since burn wound infections caused by Pseudomonas aeruginosa (PA) lead to major complications and sepsis, this study evaluates the antimicrobial efficacy of the wound irrigation solutions Prontosan (PRT), Lavanox (LAV), citric acid (CA) and mafenide acetate (MA) using microbiology assays and an ex vivo skin wound model. In suspension assays, all the solutions showed significant reductions in bacterial number (log10 reduction: CA 5.77; LAV 4.91; PRT 4.74; MA 1.23). The biofilm assay revealed that PRT and LAV reduced biofilm formation by ~25% after a 15 min treatment, while PRT was most effective after a 24 h treatment (~68%). The number of PA in biofilms measured directly after a 15 min treatment was reduced most effectively with CA and LAV (log10 reductions ~2.5), whereas after a 24 h treatment, all solutions achieved only 1.36-1.65 log10 reductions. In the skin wound model, PRT and LAV provided the highest bacterial reduction after a 15 min treatment (log10 reduction 1.8-1.9), while MA was more effective after a 22 h treatment (log10 reduction 3.6). The results demonstrated the antimicrobial efficacy of all solutions against PA. Further investigation is needed to explore the potential clinical applications of a combination or alternating use of these solutions for infection prophylaxis and treatment of wound infections caused by PA.

Bacteria and Virus Inactivation: Relative Efficacy and Mechanisms of Peroxyacids and Chlor(am)ine

Peroxyacids (POAs) are a promising alternative to chlorine for reducing the formation of disinfection byproducts. However, their capacity for microbial inactivation and mechanisms of action require further investigation. We evaluated the efficacy of three POAs (performic acid (PFA), peracetic acid (PAA), and perpropionic acid (PPA)) and chlor(am)ine for inactivation of four representative microorganisms (Escherichia coli (Gram-negative bacteria), Staphylococcus epidermidis (Gram-positive bacteria), MS2 bacteriophage (nonenveloped virus), and Φ6 (enveloped virus)) and for reaction rates with biomolecules (amino acids and nucleotides). Bacterial inactivation efficacy (in anaerobic membrane bioreactor (AnMBR) effluent) followed the order of PFA > chlorine > PAA ≈ PPA. Fluorescence microscopic analysis indicated that free chlorine induced surface damage and cell lysis rapidly, whereas POAs led to intracellular oxidative stress through penetrating the intact cell membrane. However, POAs (50 μM) were less effective than chlorine at inactivating viruses, achieving only ∼1-log PFU removal for MS2 and Φ6 after 30 min of reaction in phosphate buffer without genome damage. Results suggest that POAs' unique interaction with bacteria and ineffective viral inactivation could be attributed to their selectivity toward cysteine and methionine through oxygen-transfer reactions and limited reactivity for other biomolecules. These mechanistic insights could inform the application of POAs in water and wastewater treatment.

Efficacy and optimal dose of acetic acid to treat colonised burns wounds: protocol for a pilot randomised controlled trial

INTRODUCTION

Despite of recent advancement in the burns wound management, burn wound infection (BWI) is still one of the major cause of burns mortality. Patients who survive their burns injury still suffers from BWI related complication like delayed wound healing and poor scarring. BWI has been treated by application of topical antimicrobial agents or systemic antibiotics. Due to the global risk of developing systemic antibiotics resistance, medical research focuses on identifying single topical agent which has effective antimicrobial activity, easily available and cost effective. One such agent is acetic acid (AA). AA has been used as a topical antibacterial agent for the treatment of burns wounds for many years and has shown to have activity against gram-negative organisms including Pseudomonas aeruginosa. So far there has been no consensus on optimal concentration that has effective antimicrobial activity, frequency of application, duration of treatment and most importantly good patient's tolerability. A randomised control study is required to answer all these questions.

OBJECTIVE

To investigate the efficacy and tolerability of 0.5% and 2% of AA when applied to colonised burns wounds for 3 days after admittance to the Queen Elizabeth Hospital Birmingham.

METHODS AND ANALYSIS

This is a double-blinded, prospective, randomised, controlled, single-centre trial. Patients will be screened for eligibility in the inpatient area and those who are found to be eligible will be randomly assigned to one of two treatment groups: group 1: 0.5% AA (10 patients); group 2: 2% AA (10 patients); total number: 20 patients.

OUTCOME MEASURES

Primary outcome: Efficacy will be assessed by measuring the bacterial load from microbiology wound swabs for three consecutive days.Secondary outcomes: (1) The assessment of antimicrobial activity of AA and the minimum inhibitory concentrations. (2) Patient's tolerance by assessing Visual Analogue Scale pain score. (3) Time to 95% wound healing of treatment area. (4) Patient's perceived treatment allocation.

ETHICS AND DISSEMINATION

AceticA trial protocol was approved by the National Research Ethics Service (West Midlands-Edgbaston Research Ethics Committee; 17/WM/0407; IRAS 234132). This article refers to protocol version 5.0 dated 6 July 2020. The analysed results will be presented at national and international conferences related to management of burn patients. The generated articles based on the trial results will be submitted to peer review journals for publication.

TRIAL REGISTRATION NUMBER

ISRCTN11636684.

Bacteriological study and its antibiotics susceptibility pattern of Otitis Media in Iraqi patients

Otitis media is an acute upper respiratory tract infection-related inflammation of the middle ear and tympanic membrane, frequently affecting children. Typically, a subsequent bacterial infection complicates a viral infection, which ultimately causes the condition. The study aims to study the function of bacterial ear infections and its causes, as well as their resistance to medications, which was the focus of this investigation. The first axis of the research was the identification of bacterial isolates using recognized diagnostic tools, and the second axis was determining the antibiotic's resistance and sensitivity. Patients with otitis media were gathered from Al-Hakim General Hospital and Al-Sadr city hospital in Al-Najaf city between November 2020 and April 2021 for 100 clinical samples. More than 80 samples were found to be infected with bacteria. Bacterial strains found in this investigation are ( 30 ) isolates of Pseudomonas aeruginosa, (20) isolates of Klebsiella spp, (20) isolates of Proteus spp, ( 15 ) isolates of Staphylococcus aureus, (8) isolates Escherichia coli and (7) isolates Enterococcus fecalies. As part of this research, the disk diffusion method was used to assess how sensitive the test was. The results showed that Pseudomonas aeruginosa was resistant to most antibiotics, particularly the penicillin family, cephalosporin, and trimethoprim, with the existence of isolates resistant to meropenem. The investigation results varied for the quinolone, aminoglycoside, and macrolide families. Klebsiella spp. were tested for antibiotic sensitivity and found to be resistant to most antibiotics, particularly those in the penicillin family, cephalosporins, and trimethoprim. Some quinolones, aminoglycosides, and macrolides are also resistant. Proteus spp were resistant to most antibiotics, particularly the penicillin family (except for augmentin, which had some sensitive isolates) and cephalosporin (except for cefdinir and cefepime) had some susceptible isolates) and trimethoprim, in addition to the presence of isolates resistant to meropenem. There is a discrepancy in the examination results for the quinolone family. The aminoglycoside family is also highly resistant. S. aureus isolates were resistant to penicillin (except for augmentin, which some isolates were responsive to), trimethoprim, and quinolones, with the presence of isolates resistant to vancomycin. The macrolide class ( azithromycin) also has a significant resistance level. Escherichia coli is susceptible to meropenem, imipenem, and certain cephalosporin generations. Augmentin, cefepime, cephalothin, meropenem, imipenem, and azithromycin were ineffective against Enterococcus fecal. The conclusion is that Pseudomonas spp has a role in ear infections and the germs Klebsiella spp., Proteus spp., Staphylococcus aureus, Escherichia coli, and Enterococcus fecalies. Penicillin and cephalosporin resistance was seen in the majority of the identified isolates. The existence of isolates of Proteus and Pseudomonas species resistant to meropenem. Vancomycin-resistant strains of Staphylococcus aureus isolates are present. Keywords: Otitis media, Resistance antibiotic, S.aureus, P.aerginosa

Improved infectious burn wound healing by applying lyophilized particles containing probiotics and prebiotics

Lactiplantibacillus plantarum cells were encapsulated in a mixture of cationic and anionic polymers, with the final composition stabilized through freeze-drying. A D-optimal design was used to examine the effects of different polymer concentrations as well as adding prebiotics on the probiotic viability and swelling behavior of the formulations. Scanning electron micrographs revealed stacked particles capable of rapidly absorbing significant amounts of water. These images corresponded to initial swelling percentages of around 2000% for the optimal formulation. The optimized formula had a viability percentage of more than 82%, with the stability studies suggesting that the powders should be stored at refrigerated temperatures. The physical characteristics of the optimized formula were examined to ensure compatibility with its application. According to antimicrobial evaluations, the difference in pathogen inhibition between formulated and fresh probiotics was less than a logarithm. The final formula was tested in vivo and showed improved wound healing indicators. The optimized formula resulted in a higher rate of wound closure and infection clearance. Furthermore, the molecular studies for oxidative stress indicated that the formula could modify wound inflammatory responses. In histological investigations, the probiotic-loaded particles functioned exactly as efficaciously as silver sulfadiazine ointment did.

Gelatin-Gallic Acid Microcomplexes Release GO/Cu Nanomaterials to Eradicate Antibiotic-Resistant Microbes and Their Biofilm

Wound-infecting bacteria are typically Pseudomonas aeruginosa and Staphylococcus epidermidis, both of which form biofilms and become resistant to antibiotics. To solve this problem, copper nanoparticles (Cu) on graphene oxide (GO) nanosheets were used as antibacterial materials. Since the excessive use of antibacterial substances is fatal to normal tissues, GO/Cu was encapsulated with a gelatin complex to lower the cytotoxicity. Among the catechol-based substances, gallic acid (GA), which has anti-inflammatory and antibacterial properties, was used in this study to impart stability to the gelatin complex. Gelatin (GE) and gallic acid (GA) were combined by a crosslinking method using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS) as a crosslinker, and the crosslinking was confirmed by Fourier transform infrared (FT-IR), ¹H NMR, and the fluorescence property of GA. The GO/Cu@GE-GA microcomplexes exhibited more antibacterial effect against Gram-positive bacteria (S. epidermidis) and Gram-negative bacteria (P. aeruginosa) than when GO/Cu alone was used, and the antibiofilm effect was also confirmed. The cytotoxicity evaluation for human skin cells (human dermal fibroblast (HDF)) at the same concentration showed that it had low cytotoxicity and biocompatibility. This study shows the potential of antimicrobial gelatin microcomplex in prohibiting infectious bacteria and their biofilms and controlling the release of antimicrobial substances.

Acetic Acid Use in Chronic Wound Healing: A Multiple Case Series

BACKGROUND

Acetic acid is bacteriostatic or bactericidal to many gram-negative and gram-positive microorganisms, especially Pseudomonas. Nevertheless, it has also been found to possess cytotoxic effects in concentrations as low as 0.25% inhibiting the epithelialization process during wound healing.

CASES

In this multiple case series, we present 2 cases of chronic traumatic leg wounds treated with gauze moistened with acetic acid (0.25%), which were covered with a securing dressing and compression stockinet. Both patients were told to apply gauze moistened with acetic acid (0.25%) twice daily. In both cases, the wound progressed to blue-green drainage and wet yellow slough tissue to near-complete beefy granulation tissue. At this point, acetic acid was replaced with collagen or petrolatum dressing until complete wound closure was achieved. The treatment of these wounds illustrated successful use of acetic acid for chronic wound care.

CONCLUSION

Our experience with these cases suggests that appearance of blue-green wound drainage and wet yellow slough tissue is a reasonable indication for the use of gauze moistened with acetic acid (0.25%). Further research is needed to test the efficacy of these principles in guiding acetic acid use in wound care.

Comparison of the effectiveness of savlon antiseptic with povidone-iodine for acinetobacter baumannii infected wounds in white rats (Rattus Norvegicus)

Wound washing with antiseptic liquid is one step in the management of chronic wounds. In infected wounds, washing with antiseptic is expected to reduce bacterial colonies and help eradicate infection. One of the important pathogenic bacteria is Acinetobacter Baumannii. These opportunistic germs can form colonies, especially in patients receiving broad-spectrum antibiotic therapy, treatment in the ICU, and on skin affected by burns. Antiseptic commonly used to wash wound are Savlon and Povidone-iodine 10%. Both antiseptic are broad spectrum antisepctic, kill gram negative and gram positive bacteria. However Savlon could caused skin irritation. Therefore dilution is needed to prevent this effect. This study was intended to determine the difference and comparison of the effectiveness of Savlon and Povidone iodine antiseptic to bacterial growth on wound infected by Acinetobacter Baumannii.  This study is an experimental study with a randomized controlled trial without blinding. The wound research procedure was made on the right and left sides of the rat's back with a size of 1x1 cm each. Wounds that have been contaminated with Acinetobacter Baumannii are left for 4 hours. After 4 hours the wound will be washed and irrigated. The wound that has been made is closed with a transparent dressing.

Biopolymer Nano-Network for Antimicrobial Peptide Protection and Local Delivery

Antimicrobial resistance (AMR) develops when bacteria no longer respond to conventional antimicrobial treatment. The limited treatment options for resistant infections result in a significantly increased medical burden. Antimicrobial peptides offer advantages for treatment of resistant infections, including broad-spectrum activity and lower risk of resistance development. However, sensitivity to proteolytic cleavage often limits their clinical application. Here, a moldable and biodegradable colloidal nano-network is presented that protects bioactive peptides from enzymatic degradation and delivers them locally. An antimicrobial peptide, PA-13, is encapsulated electrostatically into positively and negatively charged nanoparticles made of chitosan and dextran sulfate without requiring chemical modification. Mixing and concentration of oppositely charged particles form a nano-network with the rheological properties of a cream or injectable hydrogel. After exposure to proteolytic enzymes, the formed nano-network loaded with PA-13 eliminates Pseudomonas aeruginosa during in vitro culture and in an ex vivo porcine skin model while the unencapsulated PA-13 shows no antibacterial effect. This demonstrates the ability of the nano-network to protect the antimicrobial peptide in an enzyme-challenged environment, such as a wound bed. Overall, the nano-network presents a useful platform for antimicrobial peptide protection and delivery without impacting peptide bioactivity.

In Vitro-In Vivo Correlation for the Antibacterial Effect of Lactiplantibacillus plantarum as a Topical Healer for Infected Burn Wound

Difficulties in delivering antimicrobial agents to wound areas and emersion of multiple drug resistant organisms (MDROs) have converted managing burn infections into a complicated task in medicine. Probiotics emerged not only as a probable solution for burn infections but also as an accelerator in the healing process. The probability of in vitro-in vivo correlation (IVIVC) in probiotic activity leads to lower costs in finding new therapeutic options. Simulated wound fluid (SWF) was used to evaluate the antibacterial function of Lactiplantibacillus plantarum in wounds. The growth parameters in SWF were evaluated using a logistic model to predict growth behavior in the wound area. In addition, probiotic antimicrobial activity and secretion of antibacterial substances in SWF were also studied. Data were used to select the initial dose and apply frequency for in vivo study. The wound models were infected by two main pathogens (Pseudomonas aeruginosa or Staphylococcus aureus). In vitro results showed less lag time associated with considerable acid production in SWF. In the following, secretion of antimicrobial substances and co-aggregation with pathogens became more important. The susceptibility of pathogens to these factors was different, and culture medium affected the yield of each factor involved in eliminating pathogens. Histological analysis and macroscopic examination of wounds revealed probiotics as effective as positive control or more. There were some differences in the antibacterial functions of probiotics in simulated and real wound environments. The in vitro effect of probiotics on removal of pathogens was not the same as the trend seen in vivo.

Prevention and treatment of burn wound infections: the role of topical antimicrobials

INTRODUCTION

Infections related to the skin are the principal drivers of morbidity and mortality following severe burn, therefore a diverse armamentarium of topical antimicrobial agents were developed over the history of burn care. The last 30 years witnessed dramatic changes in the application of surgical intervention and utilization of topical therapies.

AREAS COVERED

We explore well-known topical antimicrobial products used in burn care. First, we investigate how fundamental changes in the practice of burn surgery influenced the choice of topical therapies used. Then, we examine antimicrobial creams and ointments commonly recognized due to their long record of use in burn care. Next, we dive into antimicrobial solutions commonly used as adjuncts to surgical intervention. Finally, we explore representative antimicrobial dressings, an ever-advancing roster of products opening the door to the next era in burn care. We also describe how these new agents relate to already established tools in present-day burn care.

EXPERT OPINION

In the current day, though the wisdom of early excision and wound closure remains valid, we continue to strive to minimize aggressive wound excision and disfiguring donor tissue collection while securing rapid wound closure. To this end, antimicrobial therapies are titrated to optimize operative outcomes and provide non-operative wound care when appropriate. Antimicrobial agents bridge the gap with the next generation of skin substitute and skin replacement therapies.

In vitro and in vivo antibacterial activity of a lysine-rich scorpion peptide derivative

Antimicrobial peptides are widely acknowledged as an alternative class of antimicrobial agents. In this study, a lysine-rich scorpion peptide derivative Pacavin-5K was designed, which showed an improved antibacterial spectrum, significantly higher antibacterial activity, and lower toxicity compared to the native peptide. It also showed an improved thermal and serum stability. Notably, Pacavin-5K significantly decreased the bacterial counts in the wounded region in the mouse cutaneous infection model caused by Staphylococcus aureus and Pseudomonas aeruginosa. Moreover, Pacavin-5K did not induce bacterial resistance associated with its antibacterial mechanism disrupting the membrane. Furthermore, Pacavin-5K could kill the S. aureus cells at the biofilm state. Overall, Pacavin-5K could be a potential alternative antibacterial agent against skin infection caused by S. aureus and P. aeruginosa.

The impact of topical agents and dressing on pH and temperature on wound healing: A systematic, narrative review

To assess the impact of topical agents and dressings on surface wound pH, temperature, and subsequent wound healing. This was a systematic, narrative review of the literature, following the PRISMA (2020) guidelines. The databases searched were Medline PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Library, Embase, Web of Science, and Scopus. Data synthesis and analysis were conducted using a structured narrative synthesis. The quality of the included clinical studies was appraised using the Evidence-Based Literature (EBL) Critical Appraisal Tool. A total of six clinical studies were assessed as eligible for inclusion, A total of six dressings/topical agents were assessed and the types of wounds included non-healing chronic wounds. Of the studies, five explored pH and one explored temperature. The EBL validity of the clinical studies was low (mean quality score was 51.3%). The five clinical studies that explored pH investigated different dressings and topical agents reporting an associated reduction in pH and improved wound outcomes. One clinical study investigated the impact of topical sodium nitrite on temperature and found that sodium nitrite increased peri-wound skin temperature and improved wound outcomes with a reduction in leg ulcer size. Given the low certainty of the evidence, we cannot confidently recommend the use of any particular topical agent or dressing to manipulate pH, or temperature to improve wound outcomes. Thus, there is a need for further research to develop a greater understanding of this topic. Irish Research Council, Enterprise Partnership Scheme.

Study of Antibacterial and Anticancer Properties of bioAgNPs Synthesized Using Streptomyces sp. PBD-311B and the Application of bioAgNP-CNC/Alg as an Antibacterial Hydrogel Film against P. aeruginosa USM-AR2 and MRSA

Here, we report the extracellular biosynthesis of silver nanoparticles (AgNPs) and determination of their antibacterial and anticancer properties. We also explore the efficacy of bioAgNPs incorporated in cellulose nanocrystals (CNCs) and alginate (Alg) for the formation of an antibacterial hydrogel film. Streptomyces sp. PBD-311B was used for the biosynthesis of AgNPs. The synthesized bioAgNPs were characterized using UV-Vis spectroscopy, TEM, XRD, and FTIR analysis. Then, the bioAgNPs’ antibacterial and anticancer properties were determined using TEMA and cytotoxicity analysis. To form the antibacterial hydrogel film, bioAgNPs were mixed with a CNC and Alg solution and further characterized using FTIR analysis and a disc diffusion test. The average size of the synthesized bioAgNPs is around 69 ± 2 nm with a spherical shape. XRD analysis confirmed the formation of silver nanocrystals. FTIR analysis showed the presence of protein capping at the bioAgNP surface and could be attributed to the extracellular protein binding to bioAgNPs. The MIC value of bioAgNPs against P. aeruginosa USM-AR2 and MRSA was 6.25 mg/mL and 3.13 mg/mL, respectively. In addition, the bioAgNPs displayed cytotoxicity effects against cancer cells (DBTRG-0.5MG and MCF-7) and showed minimal effects against normal cells (SVG-p12 and MCF-10A), conferring selective toxicity. Interestingly, the bioAgNPs still exhibited inhibition activity when incorporated into CNC/Alg, which implies that the hydrogel film has antibacterial properties. It was also found that bioAgNP-CNC/Alg displayed a minimal or slow release of bioAgNPs owing to the intermolecular interaction and the hydrogel’s properties. Overall, bioAgNP-CNC/Alg is a promising antibacterial hydrogel film that showed inhibition against the pathogenic bacteria P. aeruginosa and MRSA and its application can be further evaluated for the inhibition of cancer cells. It showed benefits for surgical resection of a tumor to avoid post-operative wound infection and tumor recurrence at the surgical site.

AB569, a Novel, Topical Bactericidal Gel Formulation, Kills Pseudomonas aeruginosa and Promotes Wound Healing in a Murine Model of Burn Wound Infection

Cutaneous thermal injuries from burns/explosives are a major cause of morbidity and mortality and represent a monumental burden on our current health care system. Injury severity is predominantly due to potentially lethal sepsis caused by multidrug-resistant (MDR) bacteria such as Pseudomonas aeruginosa (MDR-PA). Thus, there is a critical need to develop novel and effective antimicrobials for the (i) prevention, (ii) treatment, and (iii) healing of such wounds that are complicated by MDR-P. aeruginosa and other bacterial infections. AB569 is a novel bactericidal tandem consisting of acidified NaNO₂ (A-NO_2-) and Na₂-EDTA. Here, we first show that AB569 acts synergistically to kill all human burn wound strains of P. aeruginosa in vitro. This was found to be due, in part, to the generation of A-NO_2--mediated nitric oxide (NO) formation coupled with the metal chelating properties of Na₂-EDTA. Using a murine scald burn wound model of P. aeruginosa infection, an AB569-Solosite gel formulation eradicated all bacteria. Futher, we also demonstrate enhanced AB569-mediated wound healing by not only accelerating wound contraction, but also by reducing levels of the proinflammatory cytokines interleukin-6 (IL-6) and IL-1β while increasing the levels of anti-inflammatory cytokine, IL-10, and granulocyte-colony-stimulating factor (G-CSF). We also observed better epidermal restoration in AB569-treated wounds. Taken together, we conclude that this study provides solid foundational evidence that AB569 can be used topically to treat highly problematic dermal insults, including wound, burn, blast, and likely, diabetic infections in civilian and military populations, and help relieve the economical burden that MDR organisms have on the global health care system.

What Is the Optimal Irrigation Solution in the Management of Periprosthetic Hip and Knee Joint Infections?

BACKGROUND

Thorough irrigation and debridement using an irrigation solution is a well-established treatment for both acute and chronic periprosthetic joint infections (PJIs). In the absence of concrete data, identifying the optimal irrigation agent and protocol remains challenging.

METHODS

A thorough review of the current literature on the various forms of irrigations and their additives was performed to evaluate the efficacy and limitations of each solution as pertaining to pathogen eradication in the treatment of PJI. As there is an overall paucity of high-quality literature comparing irrigation additives to each other and to any control, no meta-analyses could be performed. The literature was therefore summarized in this review article to give readers concise information on current irrigation options and their known risks and benefits.

RESULTS

Antiseptic solutions include povidone-iodine, chlorhexidine gluconate, acetic acid, hydrogen peroxide, sodium hypochlorite, hypochlorous acid, and preformulated commercially available combination solutions. The current literature suggests that intraoperative use of antiseptic irrigants may play a role in treating PJI, but definitive clinical studies comparing antiseptic to no antiseptic irrigation are lacking. Furthermore, no clinical head-to-head comparisons of different antiseptic irrigants have identified an optimal irrigation solution.

CONCLUSION

Further high-quality studies on the optimal irrigation additive and protocol for the management of PJI are warranted to guide future evidence-based decisions.

Role of an acidic environment in the treatment of diabetic foot infections: A review

Management of diabetic foot ulcers is the biggest challenge to the clinician, as conventional antibiotic therapies and local wound care have their own limitations. They are not effective for control of infections and promotion of healing because of cytotoxic effects. In view of cytotoxicity of routinely used topical antiseptic agents, this article focuses on the search of an ideal topical antiseptic agent that is safe and effective in controlling infectious agents and also in promoting the healing process. This review focuses on the use of various acids such as citric, acetic, hyaluronic, and hypochlorous acids as topical agents in diabetic foot infections. This article also focuses on the different roles of acids in the treatment of diabetic foot infections.

Fabrication of collagen with polyhexamethylene biguanide: A potential scaffold for infected wounds

Bacterial infection remains a great challenge in wound healing, especially in chronic wounds. Multidrug-resistant organisms are increasing in acute and chronic wound infections, which compromise the chance of therapeutics. Resistance to conventional antibiotics has created an urge to study new approach/system that can effectively control wound infection and enhance healing. Wound cover/dressing must exhibit biocompatibility and effectiveness in reducing bioburden at the wound site. Collagen, a natural biopolymer, possesses advantages over synthetic and other natural materials due to its unique biological properties. It can act as an excellent wound dressing and controlled drug delivery system. Currently, antiseptic agents such as silver, iodine, and polyhexamethylene biguanide (PHMB)-incorporated scaffolds have become widely accepted in chronic wound healing. In this study, PHMB-incorporated collagen scaffold has been prepared and characterized using Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), and differential scanning calorimetry (DSC), which showed retention of collagen nativity and integration of PHMB. The scanning electron microscopy (SEM) analysis revealed the porous structures of scaffolds. The cytotoxicity analysis showed PHMB is nontoxic at the concentration of 0.01% (wt/wt). The agar diffusion test and bacterial adhesion study demonstrated the effectiveness of PHMB-incorporated collagen scaffold against both gram positive and negative strains. This study concludes that PHMB-incorporated collagen scaffold could have the potential for infected wound healing.

Skin barrier response to active chlorine hand disinfectant-An experimental study comparing skin barrier response to active chlorine hand disinfectant and alcohol-based hand rub on healthy skin and eczematous skin

BACKGROUND

Alcohol-based hand rub (ABHR) is widely used for hand disinfection in the health care sector. ABHR is, however, known to cause discomfort when applied on damaged skin emphasizing the unmet need for alternative and better tolerated types of disinfectants. Active chlorine hand disinfectants (ACHDs) are potential new candidates; however, the effect on the skin barrier function compared to ABHR remains to be assessed.

MATERIALS AND METHODS

In Study A, the forearm skin of healthy adults was repeatedly exposed to ACHD and ABHR. Skin barrier function was assessed by measurement of transepidermal water loss, electrical conductance, pH, and erythema at baseline and at follow-up after 2 days, and subjective discomfort was likewise assessed. Study B was performed in the same way; however, in order to induce an experimental irritant contact dermatitis, sodium lauryl sulfate patch tests were applied to forearms before exposure to ACHD and ABHR.

RESULTS

In both studies, the skin barrier function was unaffected after repetitive exposure to ACHD and ABHR, and with no significant differences between the products. Subjective discomfort was reported as sporadic or very mild in relation to both products.

CONCLUSION

Our results illustrate that use of ACHD does not affect the skin barrier function negatively, neither in intact skin nor in skin with experimentally induced contact dermatitis. Future studies should include real-life evaluation of skin barrier function and subjective discomfort following ACHD use in individuals with and without hand eczema.

Chitosan/Hyaluronic acid/Alginate and an assorted polymers loaded with honey, plant, and marine compounds for progressive wound healing-Know-how

Biomaterials are being extensively used in regenerative medicine including tissue engineering applications, as these enhance tissue development, repair, and help in the process of angiogenesis. Wound healing is a crucial biological process of regeneration of ruptured tissue after getting injury to the skin and other soft tissue in humans and animals. Besides, the accumulation of microbial biofilms around the wound surface can increase the risk and physically obstruct the wound healing activity, and may even lead to amputation. Hence, in both acute and chronic wounds, prominent biomaterials are required for wound healing along with antimicrobial agents. This review comprehensively addresses the antimicrobial and wound healing effects of chitosan, chitin, cellulose acetate, hyaluronic acid, pullulan, bacterial cellulose, fibrin, alginate, etc. based wound dressing biomaterials fabricated with natural resources such as honey, plant bioactive compounds, and marine-based polymers. Due to their excellent biocompatibility and biodegradability, bioactive compounds derived from honey, plants, and marine resources are commonly used in biomedical and tissue engineering applications. Different types of polymer-based biomaterials including hydrogel, film, scaffold, nanofiber, and sponge dressings fabricated with bioactive agents including honey, curcumin, tannin, quercetin, andrographolide, gelatin, carrageenan, etc., can exhibit significant wound healing process in, diabetic wounds, diabetic ulcers, and burns, and help in cartilage repair along with good biocompatibility and antimicrobial effects. Among the reviewed biomaterials, carbohydrate polymers such as chitosan-based biomaterials are prominent and widely used for wound healing applications followed by hyaluronic acid and alginate-based biomaterials loaded with honey, plant, and marine compounds. This review first provides an overview of the vast natural resources used to formulate different biomaterials for the treatment of antimicrobial, acute, and chronic wound healing processes.

A novel method for treatment of pseudomonas pyogenic hepatic abscess complicating an echinococcal cyst by irrigation with acetic acid. A case report and literature review

Hepatic hydatid cysts can be complicated by pyogenic abscesses. We report a case of hepatic hydatid cysts presenting to Sultan Qaboos University Hospital (SQUH) on 29 June 2010 complicated by secondary infection with fully sensitive Pseudomonas aeruginosa. The infection persisted despite standard treatment (drainage and systemic antibiotics) and was eventually cured with a novel method using acetic acid.

Methods

Instillation of acetic acid (in the form of white vinegar) into the hepatic abscess through the pig tail drainage tube.

Results

The administration of acetic acid (6%) in the form of white vinegar was well tolerated and safe to the patient and resulted in complete clinical and radiographic resolution of the hepatic abscess.

Conclusion

Acetic acid (vinegar) irrigation can be used to clear a refractory pyogenic hepatic abscess due toP aeruginosa infection.

The Bactericidal Tandem Drug, AB569: How to Eradicate Antibiotic-Resistant Biofilm Pseudomonas aeruginosa in Multiple Disease Settings Including Cystic Fibrosis, Burns/Wounds and Urinary Tract Infections

The life-threatening pandemic concerning multi-drug resistant (MDR) bacteria is an evolving problem involving increased hospitalizations, billions of dollars in medical costs and a remarkably high number of deaths. Bacterial pathogens have demonstrated the capacity for spontaneous or acquired antibiotic resistance and there is virtually no pool of organisms that have not evolved such potentially clinically catastrophic properties. Although many diseases are linked to such organisms, three include cystic fibrosis (CF), burn/blast wounds and urinary tract infections (UTIs), respectively. Thus, there is a critical need to develop novel, effective antimicrobials for the prevention and treatment of such problematic infections. One of the most formidable, naturally MDR bacterial pathogens is Pseudomonas aeruginosa (PA) that is particularly susceptible to nitric oxide (NO), a component of our innate immune response. This susceptibility sets the translational stage for the use of NO-based therapeutics during the aforementioned human infections. First, we discuss how such NO therapeutics may be able to target problematic infections in each of the aforementioned infectious scenarios. Second, we describe a recent discovery based on years of foundational information, a novel drug known as AB569. AB569 is capable of forming a "time release" of NO from S-nitrosothiols (RSNO). AB569, a bactericidal tandem consisting of acidified NaNO₂ (A-NO₂ ^-) and Na₂-EDTA, is capable of killing all pathogens that are associated with the aforementioned disorders. Third, we described each disease state in brief, the known or predicted effects of AB569 on the viability of PA, its potential toxicity and highly remote possibility for resistance to develop. Finally, we conclude that AB569 can be a viable alternative or addition to conventional antibiotic regimens to treat such highly problematic MDR bacterial infections for civilian and military populations, as well as the economical burden that such organisms pose.

Insights into Emergence of Antibiotic Resistance in Acid-Adapted Enterohaemorrhagic Escherichia coli

The emergence of multidrug-resistant pathogens presents a global challenge for treating and preventing disease spread through zoonotic transmission. The water and foodborne Enterohaemorrhagic Escherichia coli (EHEC) are capable of causing intestinal and systemic diseases. The root cause of the emergence of these strains is their metabolic adaptation to environmental stressors, especially acidic pH. Acid treatment is desired to kill pathogens, but the protective mechanisms employed by EHECs cross-protect against antimicrobial peptides and thus facilitate opportunities for survival and pathogenesis. In this review, we have discussed the correlation between acid tolerance and antibiotic resistance, highlighting the identification of novel targets for potential production of antimicrobial therapeutics. We have also summarized the molecular mechanisms used by acid-adapted EHECs, such as the two-component response systems mediating structural modifications, competitive inhibition, and efflux activation that facilitate cross-protection against antimicrobial compounds. Moving beyond the descriptive studies, this review highlights low pH stress as an emerging player in the development of cross-protection against antimicrobial agents. We have also described potential gene targets for innovative therapeutic approaches to overcome the risk of multidrug-resistant diseases in healthcare and industry.

Novel treatment dynamics for biofilm-related infections

Introduction: As a result of progress in medical care, a huge number of medical devices are used in the treatment of human diseases. In turn, biofilm-related infection has become a growing threat due to the tolerance of biofilms to antimicrobials, a problem magnified by the development of antimicrobial resistance worldwide. As a result, successful treatment of biofilm-disease using only antimicrobials is problematic.Areas covered: We summarize some alternative approaches to classic antimicrobials for the treatment of biofilm disease. This review is not intended to be exhaustive but to give a clinical picture of alternatives to antimicrobial agents to manage biofilm disease. We highlight those strategies that may be closer to application in clinical practice.Expert opinion: There are a number of outstanding challenges in the development of novel antibiofilm therapies. Screening for effective antibiofilm compounds requires models relevant to all clinical scenarios. Although in vitro research of anti-biofilm strategies has progressed significantly over the past decade, there is a lack of in vivo research. In addition, the complexity of biofilm biology makes it difficult to develop a compound that is likely to provide the single 'magic bullet'. The multifaceted nature of biofilms imposes the need for multi-targeted or combinatorial therapies.

Effects of various wound dressings on microbial growth in perfused equine musculocutaneous flaps

OBJECTIVE

To compare the effect of multiple wound dressings on microbial growth in a perfused equine wound model.

SAMPLE

Abdominal musculocutaneous flaps from 16 equine cadavers.

PROCEDURES

8 full-thickness skin wound covered were created in each flap. Tissues were perfused with saline (0.9% NaCl) solution. Wounds were inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa (10⁶ CFUs), incubated, and covered with a dressing containing activated charcoal, boric acid, cadexomer iodine, calcium alginate, manuka honey, nanoparticle silver, or polyhexamethylene biguanide or with a control (nonadherent gauze) dressing. Muscle biopsy specimens were obtained at baseline (immediately prior to dressing application) and 6, 12, 18, and 24 hours later for mean bacterial load (MBL) determination. The MBLs at each subsequent time point were compared with that at baseline within dressing types, and MBLs at each time point were compared among dressing types.

RESULTS

MBLs in MRSA-inoculated wounds covered with cadexomer iodine dressings were significantly decreased from baseline at the 6- and 12-hour time points. For P aeruginosa-inoculated wounds, MBLs were significantly increased from baseline in all wounds at various times except for wounds with cadexomer iodine dressings. The MBLs of wounds with cadexomer iodine dressings were lower than all others, although not always significantly different from those for wounds with boric acid, manuka honey, nanoparticle silver, and polyhexamethylene biguanide dressings.

CONCLUSIONS AND CLINICAL RELEVANCE

In this nonviable perfused wound model, growth of MRSA and P aeruginosa was most effectively reduced or inhibited by cadexomer iodine dressings. These results and the effect of the dressings on wound healing should be confirmed with in vivo studies.

Is lymphangitic streaking associated with different pathogens?

OBJECTIVES

Little is known regarding the differences in microbiology associated with cellulitis or abscess with or without lymphangitic streaking. The objective of our study is to assess whether there are differences in the pathogens identified from wound cultures of patients with paronychia with and without associated lymphangitis.

METHODS

Retrospective cross-sectional study at a tertiary pediatric emergency department over 25 years. We opted to assess patients with paronychia of the finger, assuming that these cases will have a greater variety of causative pathogens compared to other cases of cellulitis and soft tissue abscess that are associated with nail biting. Case identification was conducted using a computerized text-screening search that was refined by manual chart review. We included patients from 1 month to 20 years of age who underwent an incision and drainage (I&D) of a paronychia and had a culture obtained. The presence or absence of lymphangitis was determined from the clinical narrative in the medical record. We excluded patients treated with antibiotics prior to I&D as well as immune-compromised patients. We used descriptive statistics for prevalence and χ2 tests for categorical variables.

RESULTS

Two hundred sixty-six patients met inclusion criteria. The median age was 9.7 years [IQR 4.7, 15.4] and 45.1% were female. Twenty-two patients (8.3%) had lymphangitic streaking associated with their paronychia. Patients with lymphangitis streaking were similar to those without lymphangitis in terms of age and sex (p = 0.52 and p = 0.82, respectively). Overall, the predominant bacteria was MSSA (40%) followed by MRSA (26%). No significant differences were found between the pathogens in the 22 patients with associated lymphangitis compared to the 244 patients without.

CONCLUSION

Staphylococcus aureus represent the majority of pathogens in paronychia, although streptococcal species and gram-negative bacteria were also common. Among patients with paronychia of the finger, there seems to be no association between pathogen type and presence of lymphangitic streaking.

Antibiofilm and antipersister activity of acetic acid against extensively drug resistant Pseudomonas aeruginosa PAW1

Pseudomonas aeruginosa is an ESKAPE pathogen associated with difficult-to-treat burn wound and surgical-site infections. This study aimed to characterise an extensively drug resistant (XDR) P. aeruginosa isolate (designated PAW1) and to investigate the antibiofilm and antipersister effect of acetic acid on PAW1. PAW1 was identified using biotypic (VITEK) and genotypic (16S rDNA) analysis. Minimum inhibitory concentration (MIC) and disc susceptibility testing showed high level resistance against all antibiotics from classes including beta lactams, cephems, carbapenems and fluoroquinolones. It was therefore identified as extensively drug resistant (XDR), showing resistance to all antibiotics except for, aminoglycoside (gentamicin and netilmicin) and lipopeptides (polymyxin B). Time kill assays showed antibiotic tolerant, persister cell formation in presence of 100X MICs of gentamicin and polymyxin B. Other virulence traits such as ability to produce lipase, protease, haemolysin, and siderophores and to form biofilms were additional factors which may contribute to its pathogenicity. PAW1 showed promising susceptibility against acetic acid with MIC and minimum biofilm inhibitory concentration of 0.156% (v/v). Percent viability of PAW1 was dependent on dose and treatment time of acetic acid. 0.625% acetic acid treatment of 5 minutes was effective in killing >90% planktonic cells showing lesser toxicity to L929 cells (IC₅₀ = 0.625%). Biofilm disruption caused due to acetic acid was also dose dependent, showing 40.57% disruption after treatment with 0.625% acetic acid for 5 minutes. FESEM imaging and live dead staining of planktonic and biofilm forms of PAW1 confirmed that acetic acid treatment caused 19.04% of cell shrinkage and disruption of extracellular matrix resulting in killing of cells. Antipersister activity of acetic acid was demonstrated by showing complete killing of PAW1 at 4X MIC. Overall, this study characterised an XDR isolate P. aeruginosa showing resistance and tolerance to various antibiotics. Antipersister and antibiofilm effect of acetic acid demonstrates the importance of forgotten topical agents as an effective strategy to treat XDR pathogens.

Burn Care in the Greek and Roman Antiquity

The last century brought about more rapid new developments in the treatment of burns, which significantly lowered the mortality of burn injuries. However, burns were already treated in antiquity, where the threshold from spirituality to scientific medicine originated. The existing literature on burn treatment is very limited and there are many cross-references, some of them incorrect. The aim of this work by an interdisciplinary team of historians and physicians is to offer a more precise reproduction of the burn treatment of Greek and Roman antiquity using original texts in context and with a modern scientific background. There are many sources from ancient doctors on the subject of burn treatment, as well as the treatment of burned-out wounds and frostbite, which have not yet been mentioned. The literature research also showed an understanding of scientific contexts in ancient medicine, such as antiseptics or rheology. Interestingly, there was a change in burn medicine from everyday Greek medicine to Roman military medicine with other burn patterns. The care of patients using analgetics and the therapy of burn shock arose from the literature. The ancient world is considered to be the foundation of medicine, but it is believed to have been based mainly on shamanism rather than science. However, already more than two millennia ago, burns were correctly assessed and treated according to today’s scientific standards and scientific relationships were recognized.

Antibacterial activity of a scorpion-derived peptide and its derivatives in vitro and in vivo

Antimicrobial peptides have recently become extremely popular as a novel class of antimicrobial agents. AMP MK049518 (FLGLLGSVLGSVLPSIFK), identified from the crab-scorpion Didymocentrus krausi, only possesses significant antibacterial activity against Gram-positive bacteria. In this study, a derivative G2K-S3K was designed with an excellent antibacterial spectrum and significantly higher antibacterial activity compared to the natural peptide. G2K-S3K also demonstrated excellent serum- and thermal-stability and did not induce bacterial resistance. In the Staphylococcus aureus and Pseudomonas aeruginosa -induced skin infection in mice, G2K-S3K significantly decreased bacterial counts in the wound by topical application. Thus, G2K-S3K could be a potent topical anti-infective agent against the skin infection caused by S. aureus and P. aeruginosa.

Understanding How Microorganisms Respond to Acid pH Is Central to Their Control and Successful Exploitation

Microbes from the three domains of life, Bacteria, Archaea, and Eukarya, share the need to sense and respond to changes in the external and internal concentrations of protons. When the proton concentration is high, acidic conditions prevail and cells must respond appropriately to ensure that macromolecules and metabolic processes are sufficiently protected to sustain life. While, we have learned much in recent decades about the mechanisms that microbes use to cope with acid, including the unique challenges presented by organic acids, there is still much to be gained from developing a deeper understanding of the effects and responses to acid in microbes. In this perspective article, we survey the key molecular mechanisms known to be important for microbial survival during acid stress and discuss how this knowledge might be relevant to microbe-based applications and processes that are consequential for humans. We discuss the research approaches that have been taken to investigate the problem and highlight promising new avenues. We discuss the influence of acid on pathogens during the course of infections and highlight the potential of using organic acids in treatments for some types of infection. We explore the influence of acid stress on photosynthetic microbes, and on biotechnological and industrial processes, including those needed to produce organic acids. We highlight the importance of understanding acid stress in controlling spoilage and pathogenic microbes in the food chain. Finally, we invite colleagues with an interest in microbial responses to low pH to participate in the EU-funded COST Action network called EuroMicropH and contribute to a comprehensive database of literature on this topic that we are making publicly available.

Comparison of the effects of Lactobacillus plantarum versus imipenem on infected burn wound healing

Background: Infection of burn wounds is one of the most important problems in the world. Lactobacillus plantarum is known for burn wound healing because of the immunomodulatory and anti-microbial roles. This study was performed to compare the effects of L. plantarum and imipenem - alone and in combination - on infected burn wound healing. Methods: Burn wounds were experimentally induced on 50 rats in three test groups (germ and supernatant of L. plantarum ) and two control groups (n=10 each) and were inoculated with Pseudomonas aeruginosa. During a 14-day period, wounds in all groups were daily treated topically. The data were analyzed using one-way analysis of variance followed by Tukey-Kramer and LSD. A p-value of < 0.05 was considered as statistically significant. Results: The mean size of the wound on day 14 after the treatment in the probiotic group was significantly lower than the control and the supernatant treated groups (p<0.05). The percentage of wound healing was significantly higher in the probiotic pellet treated group compared to the imipenem and the supernatant groups (by Anova test: 69.58%, p=0.022). The mean leukocyte count in the probiotic pellet group (12110) and supernatant group (13650) was significantly higher than the imipenem group (7670) (p=0.002 and 0.001, respectively). Wound cultures revealed that the percentage of cases where the pathogens had no growth was significantly different among the comparison groups. In all three test groups, P. aeruginosa was completely eliminated in comparison to the positive control group (p<0.05). Conclusion: The results of our study showed that L. plantarum and its by-products promote wound healing and can be used as an alternative to antibiotics to treat ulcer infections caused by resistant bacteria.