Role of therapeutic treatment with antiseptic solutions in the care of diabetic foot ulcers

BACKGROUND

Diabetic foot ulcers (DFUs) are a prevalent and severe complication of diabetes, leading to significant morbidity, impaired health-related quality of life (HRQoL) and economic burden on healthcare systems. The complexity of DFUs often results in prolonged healing and high recurrence rates. Effective management strategies are crucial for improving outcomes and reducing complications.

AIM

This study aimed to review the efficacy of antiseptic solutions in the treatment and care of DFUs.

METHOD

A literature analysis was conducted to review clinical studies and guidelines on the use and efficacy of antiseptic solutions, particularly Octenisept® (0.1% octenidine dihydrochloride and 2% 2-phenoxyethanol). The review focused on the antimicrobial properties, biofilm-disruption capabilities and wound healing outcomes associated with the use of antiseptic solutions in DFU management.

RESULTS

Antiseptic solutions have potential to reduce bioburden, disrupt biofilm and modulate healing. There is a need to balance antimicrobial clinical efficacy with tolerability and cytotoxicity. The use and choice of adjunctive antiseptic solutions must be tailored to the patient, as antimicrobial efficacy can vary for antiseptic solutions, particularly for hypochlorous solutions. It is important to use products according to their instructions, with consideration of minimum contact time to maximise clinical efficacy. Low-pressure irrigation is adjunctive, and concurrent wound-bed preparation, including debridement, frequent inspection, infection and moisture control, remain important.

CONCLUSIONS

The therapeutic application of antiseptic solutions in DFU care presents a promising approach to enhancing wound healing and reducing infection risks. Integrating these solutions into standard wound care protocols could lower the incidence of complications, improve HRQoL and decrease the economic burden associated with diabetic foot disease. Further large-scale studies are recommended to validate these findings and refine guidelines for antiseptic use in DFU management.

Enzyme-Linked Lipid Nanocarriers for Coping Pseudomonal Pulmonary Infection. Would Nanocarriers Complement Biofilm Disruption or Pave Its Road?

Introduction

Cystic fibrosis (CF) is associated with pulmonary Pseudomonas aeruginosa infections persistent to antibiotics.

Methods

To eradicate pseudomonal biofilms, solid lipid nanoparticles (SLNs) loaded with quorum-sensing-inhibitor (QSI, disrupting bacterial crosstalk), coated with chitosan (CS, improving internalization) and immobilized with alginate lyase (AL, destroying alginate biofilms) were developed.

Results

SLNs (140-205 nm) showed prolonged release of QSI with no sign of acute toxicity to A549 and Calu-3 cells. The CS coating improved uptake, whereas immobilized-AL ensured >1.5-fold higher uptake and doubled SLN diffusion across the artificial biofilm sputum model. Respirable microparticles comprising SLNs in carbohydrate matrix elicited aerodynamic diameters MMAD (3.54, 2.48 µm) and fine-particle-fraction FPF (65, 48%) for anionic and cationic SLNs, respectively. The antimicrobial and/or antibiofilm activity of SLNs was explored in Pseudomonas aeruginosa reference mucoid/nonmucoid strains as well as clinical isolates. The full growth inhibition of planktonic bacteria was dependent on SLN type, concentration, growth medium, and strain. OD measurements and live/dead staining proved that anionic SLNs efficiently ceased biofilm formation and eradicated established biofilms, whereas cationic SLNs unexpectedly promoted biofilm progression. AL immobilization increased biofilm vulnerability; instead, CS coating increased biofilm formation confirmed by 3D-time lapse confocal imaging. Incubation of SLNs with mature biofilms of P. aeruginosa isolates increased biofilm density by an average of 1.5-fold. CLSM further confirmed the binding and uptake of the labeled SLNs in P. aeruginosa biofilms. Considerable uptake of CS-coated SLNs in non-mucoid strains could be observed presumably due to interaction of chitosan with LPS glycolipids in the outer cell membrane of P. aeruginosa.

Conclusion

The biofilm-destructive potential of QSI/SLNs/AL inhalation is promising for site-specific biofilm-targeted interventional CF therapy. Nevertheless, the intrinsic/extrinsic fundamentals of nanocarrier-biofilm interactions require further investigation.

In Vitro Antimicrobial Susceptibility Testing of Biofilm-Growing Bacteria: Current and Emerging Methods

The antibiotic susceptibility of bacterial pathogens is typically determined based on planktonic cells, as recommended by several international guidelines. However, most of chronic infections - such as those established in wounds, cystic fibrosis lung, and onto indwelling devices - are associated to the formation of biofilms, communities of clustered bacteria attached onto a surface, abiotic or biotic, and embedded in an extracellular matrix produced by the bacteria and complexed with molecules from the host. Sessile microorganisms show significantly increased tolerance/resistance to antibiotics compared with planktonic counterparts. Consequently, antibiotic concentrations used in standard antimicrobial susceptibility tests, although effective against planktonic bacteria in vitro, are not predictive of the concentrations required to eradicate biofilm-related infections, thus leading to treatment failure, chronicization and removal of material in patients with indwelling medical devices.Meeting the need for the in vitro evaluation of biofilm susceptibility to antibiotics, here we reviewed several methods proposed in literature highlighting their advantages and limitations to guide scientists towards an appropriate choice.

Pathogenic features and characteristics of food borne pathogens biofilm: Biomass, viability and matrix

Biofilm is a ubiquitous growth pattern of bacterial species survival but is notorious for its threat on public health and food contamination. Extensive studies of the biofilm structure, formation, quantification, quorum sensing system and underlying control strategies have been reported during the past decades. Insightful elucidation of the pathogenic features and characteristic of bacterial biofilm can facilitate in devising appropriate control strategies for biofilm eradication. Therefore, this review mainly summarized the pathogenic features of biofilms from food borne microorganisms, including the biomass (which could be quantified using crystal violet and fluorogenic dye Syto9 assays), viability (which could be determined by tetrazolium salts, fluorescein diacetate, resazurin staining and alamar blue assays) and matrix (which are commonly detected by dimethyl methylene blue and wheat germ agglutinin assays). In addition, three features were further compared with its particular benefits in specific application.