Povidone iodine in wound healing: A review of current concepts and practices

Quaternary ammonium N,N,N-trimethyl chitosan derivative and povidone‑iodine complex as a potent antiseptic with enhanced wound healing property

The importance of developing more potent antimicrobials and robust infection prevention practices has been highlighted recently with the increase in reports of emerging bacterial resistance mechanisms and the development of antibiotic-resistant microbes. In this study, a quaternary ammonium chitosan derivative, N,N,N-trimethyl chitosan chloride (TMC) with inherent bactericidal property was synthesized and complexed with povidone‑iodine (PVP-I) to create a potentially more potent antiseptic solution that could also significantly enhance the wound healing process. TMC, a positively charged, water-soluble derivative of chitosan, formed stable solutions with PVP-I at 5% w/v TMC concentration (TMC5/PVP-I). TMC5/PVP-I was significantly effective against multidrug-resistant bacteria S. aureus compared with PVP-I alone. TMC/PVP-I solutions also showed fungicidal property against C. albicans, with no cytotoxic effects when tested against human fibroblast cells cultured in vitro. Wound healing assessment in vivo revealed early collagen formation and re-epithelialization for TMC5/PVP-I treated wounds in rats relative to control and PVP-I only. Formulation of TMC/PVP-I solutions presented in the study can be easily adapted in the existing production of commercial PVP-I creating a new product with more potent bactericidal and enhanced wound healing properties for optimal wound care.

Povidone Iodine Disinfection Associated with Hypothyroidism and Potentially Contributing to Prolonged Kidney Failure

Objectives

To report a case of povidone-iodine (PVP-I, Iso-Betadine®) disinfection of lower leg fasciotomy wounds resulting in iodide absorption and possibly contributing to hypothyroidism and prolonged kidney injury.

Design

Case report. Setting. Pediatric intensive care unit (PICU), university hospital. Patients. A 13-year-old patient presenting with prolonged oligoanuric kidney failure and unexplained primary hypothyroidism three weeks after severe abdominal sepsis with multiple organ dysfunction and major rhabdomyolysis due to bilateral lower leg compartment syndrome, necessitating moderate size fasciotomies, disinfected daily with PVP-I. Interventions. Interruption of PVP-I exposure and initiation of thyroid hormone substitution. Measurements and Main Results. Hypothyroidism was revealed during diagnostic work-up for persistent hypertriglyceridemia. Thyroxine (T4) (4.0 mg/L) and tri-iodothyronine (T3) (64 ng/L) were moderately low, yet thyroid stimulating hormone (TSH) (16.8 mIU/L) was fourfold the maximal normal range value. This pattern, atypical for prolonged critical illness-related hypothyroidism, prompted interruption of PVP-I exposure and initiation of thyroid hormone substitution. Urinary production and creatinine clearance recovered during the following days, and one week later, intermittent renal replacement therapy could be terminated, suggesting that PVP-I toxicity and/or hypothyroidism may have contributed to the persistent renal failure three weeks after resolved septic shock and rhabdomyolysis. Elevated serum and urinary anion gap normalized simultaneously, but this evolution of rather nonspecific indices could be multifactorial.

Conclusion

PVP-I is a commonly used broad-spectrum antimicrobial agent for prevention and treatment of wound infections. Toxic complications due to PVP-I absorption, after disinfection of extended thermal injuries larger than 20% of the body surface, have been described. In critically ill children, however, toxic effects of PVP-I may occur due to repeated disinfection of less extended wounds. Proposed screening strategies include: monitoring of the volumes of PVP-I applied daily; of the thyroid function, the serum, and/or urinary anion gap and the urinary iodide concentrations. These strategies, however, remain to be validated. This case report should be a wake-up call for daily integration of wound management in the clinical evaluation of critically ill patients.

Facile Synthesis of Bio-Antimicrobials with "Smart" Triiodides

Multi-drug resistant pathogens are a rising danger for the future of mankind. Iodine (I₂) is a centuries-old microbicide, but leads to skin discoloration, irritation, and uncontrolled iodine release. Plants rich in phytochemicals have a long history in basic health care. Aloe Vera Barbadensis Miller (AV) and Salvia officinalis L. (Sage) are effectively utilized against different ailments. Previously, we investigated the antimicrobial activities of smart triiodides and iodinated AV hybrids. In this work, we combined iodine with Sage extracts and pure AV gel with polyvinylpyrrolidone (PVP) as an encapsulating and stabilizing agent. Fourier transform infrared spectroscopy (FT-IR), Ultraviolet-visible spectroscopy (UV-Vis), Surface-Enhanced Raman Spectroscopy (SERS), microstructural analysis by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-Ray-Diffraction (XRD) analysis verified the composition of AV-PVP-Sage-I₂. Antimicrobial properties were investigated by disc diffusion method against 10 reference microbial strains in comparison to gentamicin and nystatin. We impregnated surgical sutures with our biohybrid and tested their inhibitory effects. AV-PVP-Sage-I₂ showed excellent to intermediate antimicrobial activity in discs and sutures. The iodine within the polymeric biomaterial AV-PVP-Sage-I₂ and the synergistic action of the two plant extracts enhanced the microbial inhibition. Our compound has potential for use as an antifungal agent, disinfectant and coating material on sutures to prevent surgical site infections.

Update on the role of antiseptics in the management of chronic wounds with critical colonisation and/or biofilm

Biofilms play a major role in delaying chronic wounds from healing. A wound infiltrated with biofilm, or "critically colonised" wound, may become clinically infected if the number of microbes exceeds a critical level. Chronic wound biofilms represent a significant treatment challenge by demonstrating recalcitrance towards antimicrobial agents. However, a "window of opportunity" may exist after wound debridement when biofilms are more susceptible to topical antiseptics. Here, we discuss the role of antiseptics in the management of chronic wounds and biofilm, focusing on povidone-iodine (PVP-I) in comparison with two commonly used antiseptics: polyhexanide (PHMB) and silver. This article is based on the literature reviewed during a focus group meeting on antiseptics in wound care and biofilm management, and on a PubMed search conducted in March 2020. Compared with PHMB and silver, PVP-I has a broader spectrum of antimicrobial activity, potent antibiofilm efficacy, no acquired bacterial resistance or cross-resistance, low cytotoxicity, good tolerability, and an ability to promote wound healing. PVP-I represents a viable therapeutic option in wound care and biofilm management, with the potential to treat biofilm-infiltrated, critically colonised wounds. We propose a practical algorithm to guide the management of chronic, non-healing wounds due to critical colonisation or biofilm, using PVP-I.

Driveline exit-site care protocols in patients with left ventricular assist devices: a systematic review

 

OBJECTIVES

Driveline infections continue to be a significant complication following left ventricular assist device (LVAD) implantation. Driveline exit-site care is crucial for the prevention of infections; however, there are no uniform guidelines. The goal of this study was to provide an overview of the currently published driveline exit-site care protocols in patients with LVAD.

METHODS

A systematic literature review was performed. Studies before 15 December 2020 were included if the number of driveline infections was a primary outcome and the driveline exit-site care protocol was explained.

RESULTS

Eleven articles were included in the systematic review, including 1602 patients with LVADs. The median of the frequency of driveline infections in the articles was 13.8% with a range of 0–52.6%. There was a marked variability in the methods of care of driveline exit sites, without a standardized driveline dressing technique in patients with LVADs. The frequency of driveline infections was 6–7.5% in studies using a dressing kit that included chlorhexidine, a silver-based dressing and an anchoring device. Furthermore, there was variability in the anchoring devices and the frequency of dressing changes, which varied from daily to weekly. No specific anchoring device or change frequency was found to be superior.

CONCLUSIONS

Based on this systematic review, driveline exit care protocols that included chlorhexidine, a silver-based dressing, the use of an anchoring device and dressing kits might be best in reducing driveline infection rates. However, prospective studies with larger cohorts are needed to establish the optimal protocol for driveline exit-site care.

Activity of Povidone in Recent Biomedical Applications with Emphasis on Micro- and Nano Drug Delivery Systems

Due to the unwanted toxic properties of some drugs, new efficient methods of protection of the organisms against that toxicity are required. New materials are synthesized to effectively disseminate the active substance without affecting the healthy cells. Thus far, a number of polymers have been applied to build novel drug delivery systems. One of interesting polymers for this purpose is povidone, pVP. Contrary to other polymeric materials, the synthesis of povidone nanoparticles can take place under various condition, due to good solubility of this polymer in several organic and inorganic solvents. Moreover, povidone is known as nontoxic, non-carcinogenic, and temperature-insensitive substance. Its flexible design and the presence of various functional groups allow connection with the hydrophobic and hydrophilic drugs. It is worth noting, that pVP is regarded as an ecofriendly substance. Despite wide application of pVP in medicine, it was not often selected for the production of drug carriers. This review article is focused on recent reports on the role povidone can play in micro- and nano drug delivery systems. Advantages and possible threats resulting from the use of povidone are indicated. Moreover, popular biomedical aspects are discussed.

Developments and challenges in dermatology: an update from the Interactive Derma Academy (IDeA) 2019

The 2019 Interactive Derma Academy (IDeA) meeting was held in Lisbon, Portugal, 10-12 May, bringing together leading dermatology experts from across Europe, the Middle East and Asia. Over three days, the latest developments and challenges in relation to the pathophysiology, diagnosis, evaluation and management of dermatological conditions were presented, with a particular focus on acne, atopic dermatitis (AD) and actinic keratosis (AK). Interesting clinical case studies relating to these key topics were discussed with attendees to establish current evidence-based best practices. Presentations reviewed current treatments, potential therapeutic approaches and key considerations in the management of acne, AK and AD, and discussed the importance of the microbiome in these conditions, as well as the provision of patient education/support. It was highlighted that active treatment is not always required for AK, depending on patient preferences and clinical circumstances. In addition to presentations, two interactive workshops on the diagnosis and treatment of sexually transmitted infections/diseases (STIs/STDs) presenting to the dermatology clinic, and current and future dermocosmetics were conducted. The potential for misdiagnosis of STIs/STDs was discussed, with dermoscopy and/or reflectance confocal microscopy suggested as useful diagnostic techniques. In addition, botulinum toxin was introduced as a potential dermocosmetic, and the possibility of microbiome alteration in the treatment of dermatological conditions emphasized. Furthermore, several challenges in dermatology, including the use of lasers, the complexity of atopic dermatitis, wound care, use of biosimilars and application of non-invasive techniques in skin cancer diagnosis were reviewed. In this supplement, we provide an overview of the presentations and discussions from the fourth successful IDeA meeting, summarizing the key insights shared by dermatologists from across the globe.

Antimicrobial stewardship strategies in wound care: evidence to support the use of dialkylcarbamoyl chloride (DACC)- coated wound dressings

BACKGROUND

Traditionally, infections are treated with antimicrobials (for example, antibiotics, antiseptics, etc), but antimicrobial resistance (AMR) has become one of the most serious health threats of the 21st century (before the emergence of COVID-19). Wounds can be a source of infection by allowing unconstrained entry of microorganisms into the body, including antimicrobial-resistant bacteria. The development of new antimicrobials (particularly antibiotics) is not keeping pace with the evolution of resistant microorganisms and novel ways of addressing this problem are urgently required. One such initiative has been the development of antimicrobial stewardship (AMS) programmes, which educate healthcare workers, and control the prescribing and targeting of antimicrobials to reduce the likelihood of AMR. Of great importance has been the European Wound Management Association (EWMA) in supporting AMS by providing practical recommendations for optimising antimicrobial therapy for the treatment of wound infection. The use of wound dressings that use a physical sequestration and retention approach rather than antimicrobial agents to reduce bacterial burden offers a novel approach that supports AMS. Bacterial-binding by dressings and their physical removal, rather than active killing, minimises their damage and hence prevents the release of damaging endotoxins.

AIM

Our objective is to highlight AMS for the promotion of the judicious use of antimicrobials and to investigate how dialkylcarbamoyl chloride (DACC)-coated dressings can support AMS goals.

METHOD

MEDLINE, Cochrane Database of Systematic Reviews, and Google Scholar were searched to identify published articles describing data relating to AMS, and the use of a variety of wound dressings in the prevention and/or treatment of wound infections. The evidence supporting alternative wound dressings that can reduce bioburden and prevent and/or treat wound infection in a manner that does not kill or damage the microorganisms (for example, by actively binding and removing intact microorganisms from wounds) were then narratively reviewed.

RESULTS

The evidence reviewed here demonstrates that using bacterial-binding wound dressings that act in a physical manner (for example, DACC-coated dressings) as an alternative approach to preventing and/or treating infection in both acute and hard-to-heal wounds does not exacerbate AMR and supports AMS.

CONCLUSION

Some wound dressings work via a mechanism that promotes the binding and physical uptake, sequestration and removal of intact microorganisms from the wound bed (for example, a wound dressing that uses DACC technology to successfully prevent/reduce infection). They provide a valuable tool that aligns with the requirements of AMS (for example, reducing the use of antimicrobials in wound treatment regimens) by effectively reducing wound bioburden without inducing/selecting for resistant bacteria.

Effects of Buprenorphine, Chlorhexidine, and Low-level Laser Therapy on Wound Healing in Mice

Systemic buprenorphine and topical antiseptics such as chlorhexidine are frequently used in research animals to aid in pain control and to reduce infection, respectively. These therapeutics are controversial, especially when used in wound healing studies, due to conflicting data suggesting that they delay wound healing. Low-level laser therapy (LLLT) has been used to aid in wound healing without exerting the systemic effects of therapies such as buprenorphine. We conducted 2 studies to investigate the effects of these common treatment modalities on the rate of wound healing in mice. The first study used models of punch biopsy and dermal abrasion to assess whether buprenorphine HCl or 0.12% chlorhexidine delayed wound healing. The second study investigated the effects of sustained-released buprenorphine, 0.05% chlorhexidine, and LLLT on excisional wound healing. The rate of wound healing was assessed by obtaining photographs on days 0, 2, 4, 7, and 9 for the punch biopsy model in study 1, days 0, 1, 2, 4, 6, 8, 11, and 13 for the dermal abrasion model in study 1, and days 0, 3, 6, and 10 for the mice in study 2. Image J software was used to analyze the photographed wounds to determine the wound area. When comparing the wound area on the above days to the original wound area, no significant differences in healing were observed for any of the treatment groups at any time period for either study. Given the results of these studies, we believe that systemic buprenorphine, topical chlorhexidine, and LLLT can be used without impairing or delaying wound healing in mice.

In Vitro Efficacy of Bacterial Cellulose Dressings Chemisorbed with Antiseptics against Biofilm Formed by Pathogens Isolated from Chronic Wounds

Local administration of antiseptics is required to prevent and fight against biofilm-based infections of chronic wounds. One of the methods used for delivering antiseptics to infected wounds is the application of dressings chemisorbed with antimicrobials. Dressings made of bacterial cellulose (BC) display several features, making them suitable for such a purpose. This work aimed to compare the activity of commonly used antiseptic molecules: octenidine, polyhexanide, povidone-iodine, chlorhexidine, ethacridine lactate, and hypochlorous solutions and to evaluate their usefulness as active substances of BC dressings against 48 bacterial strains (8 species) and 6 yeast strains (1 species). A silver dressing was applied as a control material of proven antimicrobial activity. The methodology applied included the assessment of minimal inhibitory concentrations (MIC) and minimal biofilm eradication concentration (MBEC), the modified disc-diffusion method, and the modified antibiofilm dressing activity measurement (A.D.A.M.) method. While in 96-well plate-based methods (MIC and MBEC assessment), the highest antimicrobial activity was recorded for chlorhexidine, in the modified disc-diffusion method and in the modified A.D.A.M test, povidone-iodine performed the best. In an in vitro setting simulating chronic wound conditions, BC dressings chemisorbed with polyhexanide, octenidine, or povidone-iodine displayed a similar or even higher antibiofilm activity than the control dressing containing silver molecules. If translated into clinical conditions, the obtained results suggest high applicability of BC dressings chemisorbed with antiseptics to eradicate biofilm from chronic wounds.

Biofilm-Innate Immune Interface: Contribution to Chronic Wound Formation

Delayed wound healing can cause significant issues for immobile and ageing individuals as well as those living with co-morbid conditions such as diabetes, cardiovascular disease, and cancer. These delays increase a patient’s risk for infection and, in severe cases, can result in the formation of chronic, non-healing ulcers (e.g., diabetic foot ulcers, surgical site infections, pressure ulcers and venous leg ulcers). Chronic wounds are very difficult and expensive to treat and there is an urgent need to develop more effective therapeutics that restore healing processes. Sustained innate immune activation and inflammation are common features observed across most chronic wound types. However, the factors driving this activation remain incompletely understood. Emerging evidence suggests that the composition and structure of the wound microbiome may play a central role in driving this dysregulated activation but the cellular and molecular mechanisms underlying these processes require further investigation. In this review, we will discuss the current literature on: 1) how bacterial populations and biofilms contribute to chronic wound formation, 2) the role of bacteria and biofilms in driving dysfunctional innate immune responses in chronic wounds, and 3) therapeutics currently available (or underdevelopment) that target bacteria-innate immune interactions to improve healing. We will also discuss potential issues in studying the complexity of immune-biofilm interactions in chronic wounds and explore future areas of investigation for the field.

Comparison of topical honey and povidone iodine-based dressings for wound healing: a systematic review and meta-analysis

OBJECTIVES

In this review and meta-analysis, we analyse the evidence to compare the efficacy of honey and povidone iodine-based dressings on the outcome of wound healing.

METHOD

A systematic literature search was performed using PRISMA guidelines in academic databases including MEDLINE, Scopus, Embase and CENTRAL. A meta-analysis was carried out to assess the effect of honey and povidone iodine-based dressings on mean healing duration, mean hospital stay duration and visual analogue scale (VAS) score of pain.

RESULTS

From the search, 12 manuscripts with a total of 1236 participants (mean age: 40.7±11.7 years) were included. The honey-based dressings demonstrated a medium-to-large effect in reduction of mean healing duration (Hedge's g: -0.81), length of hospital stay (-3.1) and VAS score (-1.2) as compared with the povidone iodine-based dressings. We present evidence (level 1b) in favour of using honey for improvement of wound recovery as compared with povidone iodine.

CONCLUSION

This review and meta-analysis demonstrate beneficial effects of honey-based dressings over povidone iodine-based dressings for wound recovery.

Low-Concentration (0.66%) Povidone Iodine Treatment of a Corneal Ulcer in a Rheumatoid Arthritis Patient

Patient: Female, 89-year-old

Final Diagnosis: Corneal ulcer

Symptoms: Low vision

Medication:—

Clinical Procedure: —

Specialty: Ophthalmology

Disinfectants In Interventional Practices

PURPOSE OF REVIEW

This review aims to provide relevant, aggregate information about a variety of disinfectants and antiseptics, along with potential utility and limitations. While not exhaustive, this review's goal is to add to the body of literature available on this topic and give interventional providers and practitioners an additional resource to consider when performing procedures.

RECENT FINDINGS

In the current SARS-CoV2 epidemiological environment, infection control and costs associated with healthcare-associated infections (HAIs) are of paramount importance. Even before the onset of SARS-CoV2, HAIs affected nearly 2million patients a year in the USA and resulted in nearly 90,000 deaths, all of which resulted in a cost to hospitals ranging from US$28 billion to 45 billion. The onset SARS-CoV2, though not spread by an airborne route, has heightened infection control protocols in hospitals and, as such, cast a renewed focus on disinfectants and their utility across different settings and organisms. The aim of this review is to provide a comprehensive overview of disinfectants used in the inpatient setting.

Povidone iodine for the treatment of adenoviral conjunctivitis

Adenoviral conjunctivitis is the most common cause of ocular viral infection in the world, but currently has no approved therapeutic treatments. The antiseptic povidone-iodine (PVP-I) has been used as an off-label treatment for the condition, but high-quality evidence for its use is limited. This paper aims to review the literature surrounding the use of PVP-I in the management of adenoviral conjunctivitis. Unfortunately, treatment regimens, inclusion criteria, outcome measures, and review periods vary widely between studies, making direct comparisons between outcomes difficult. The majority of studies investigate daily instillation of 0.4 to 2.0% PVP-I rather than one-time instillation of PVP-I as has been used anecdotally in practice. In addition, only one treatment arm investigates daily PVP-I alone, with no significant difference in the duration of disease or clinical outcome compared to placebo. All other treatment arms investigate PVP-I in combination with dexamethasone which generally improve outcomes. Tolerability of PVP-I is generally good for low concentrations <1.0%, but efficacy of treatment is generally reported to be concentration dependent. Future research should investigate the optimal concentration, dosing regimen and role of each agent in combination treatment and aim to use laboratory techniques to improve diagnosis and provide quantifiable outcomes.

Comparative in vitro evaluation of the antimicrobial activities of povidone-iodine and other commercially available antiseptics against clinically relevant pathogens

Aims: Antiseptics, such as povidone-iodine (PVP-I), play an important role in infection control across a wide range of clinical settings. This study aimed to evaluate the comparative in vitro efficacy and rate of onset of action of a range of formulations of PVP-I and other commonly used antiseptics. Methods: The antimicrobial efficacy of a range of antiseptics and antimicrobial agents used for skin, wound, vagina and oral antisepsis was evaluated according to the EU Standards DIN EN1276 and EN14476. The panel of organisms tested included bacterial and fungal pathogens and two enteroviruses (Coxsackievirus A16 [CA16] and Enterovirus 71 [EV71]). Results: All PVP-I products tested were highly efficacious in vitro (>99.99% kill rate) against a range of clinically relevant bacterial and fungal pathogens with rapid onset of action (30-60 seconds), at both high and low concentrations. By comparison, the efficacy of other antiseptics tested was generally reduced upon dilution. PVP-I products used in wound and oral care were found to be more effective in vitro against CA16 and EV71, and had a faster onset of action than most other agents tested. Conclusion: This study provides valuable insights into the in vitro efficacy of a range of commonly used antiseptics and may help inform the selection of appropriate antiseptics by healthcare professionals.

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.

Formulation Development of Topical Preparation Containing Nanoparticles of Povidone-Iodine for Wound Healing

Povidone-iodine (PVI) is an antiseptic drug that is used for wound healing or for repair of the damaged tissue. Studies on solid lipid nanoparticles (SLNs) indicate that this system could potentially be used as a delivery system with improved drug entrapment efficiency and controlled drug release for hydrophilic actives. This study focuses on developing a topical gel containing SLNs of PVI for wound healing. SLNs were prepared by using the solvent emulsification diffusion method. Lipids such as glycerol monostearate, palmitic acid, and stearic acid, and surfactants such as polysorbate 80, soyalecithin, and Pluronic F-68 were used for the preparation of SLN. These were screened out based on particle size and entrapment efficiency of SLN. Gel was prepared by using Carbopol 940 (1% w/w) and propylene glycol (10% w/w). Formulated SLNs were evaluated by various in vitro and in vivo techniques. Based on the results, the drug-to-lipid ratio (1:3) and 2% polysorbate 80 (surfactant) along with stirring rate (3,000 rpm) produced the desired particle size (285.4 nm) with good stability. 22.85% drug loading and 88.83% drug entrapment efficiency were found in the optimized formulation. In vitro drug release shows that it follows the Korsmeyer-Peppas model. The animal study shows that the period of epithelization produced by the test group was 17.14 ± 1.35 days, which was near to that of the standard group (16.25 ± 1.24 days). Clinical Trial Registration number: 1044/PO/Re/S/07/CPCSEA.

A Critical Review of Disinfection Processes to Control SARS-CoV-2 Transmission in the Food Industry

Industries of the food sector have made a great effort to control SARS-CoV-2 indirect transmission, through objects or surfaces, by updating cleaning and disinfection protocols previously focused on inactivating other pathogens, as well as food spoilage microorganisms. The information, although scarce at the beginning of the COVID-19 pandemic, has started to be sufficiently reliable to avoid over-conservative disinfection procedures. This work reviews the literature to propose a holistic view of the disinfection process where the decision variables, such as type and concentration of active substances, are optimised to guarantee the inactivation of SARS-CoV-2 and other usual pathogens and spoilage microorganisms while minimising possible side-effects on the environment and animal and human health.

Topical effect of benzalkonium bromide on wound healing and potential cellular and molecular mechanisms

Benzalkonium bromide (BB) has been widely used as a skin antiseptic for wound management. However, BB had proinflammation and reactive oxygen species (ROS) induction effect, making its role in wound healing complex and unclear. A rat full-thickness skin defect wound model was established. The effects of BB, povidone iodine (PVP-I), chlorhexidine gluconate (CHG), and normal saline (NS) on wound healing and infection control were then evaluated based on wound healing rate (WHr) and bacterial killing. The wound tissues were sectioned for histopathological evaluation and nuclear factor E2 related factor 2 (Nrf2) expression determination. The ROS production, Nrf2 activation, and heme oxygenase 1 (HO-1) expression of the HaCat cells and the cytotoxicity treated with BB were further explored. Compared with NS, PVP-I, and CHG, BB showed the best wound infection control efficiency while delayed wound healing with the WHr of 91.42 ± 5.12% at day 20. The wound tissue of the BB group showed many inflammatory cells but few granulation tissue and capillaries and no obvious collagen deposition, resulting in the lowest histopathological scores of 4.17 ± 0.75 for BB group. BB showed higher cytotoxicity on HaCat cells with the lowest IC25, IC50, and IC75 of 1.90, 4.16, and 9.09 g/mL compared with PVP-I and CHG. TUNEL staining evaluated the cytotoxicity of BB on wound tissue, which indicates the high apoptosis index BB group (5.05 ± 1.77). Compared with PVP-I and CHG, BB induced much more cell apoptosis. The results of flow cytometry and fluorescence staining showed that PVP-I, CHG, and BB induced ROS production in a concentration-dependent manner and cells treated with BB had the highest ROS production at the same inhibition concentration. The cells and the wound tissues treated with BB showed highest Nrf2 activation and HO-1 expression than PVP-I and CHG. BB was highly efficient in wound infection control while delayed wound healing. The prolonged and strengthened inflammation and the raised ROS production originating from BB administration may contribute to delayed wound healing.

Molecular Iodine Has Extrathyroidal Effects as an Antioxidant, Differentiator, and Immunomodulator

Most investigations of iodine metabolism in humans and animals have focused on its role in thyroid function. However, considerable evidence indicates that iodine could also be implicated in the physiopathology of other organs. We review the literature that shows that molecular iodine (I₂) exerts multiple and complex actions on the organs that capture it, not including its effects as part of thyroid hormones. This chemical form of iodine is internalized by a facilitated diffusion system that is evolutionary conserved, and its effects appear to be mediated by a variety of mechanisms and pathways. As an oxidized component, it directly neutralizes free radicals, induces the expression of type II antioxidant enzymes, or inactivates proinflammatory pathways. In neoplastic cells, I₂ generates iodolipids with nuclear actions that include the activation of apoptotic pathways and the inhibition of markers related to stem cell maintenance, chemoresistance, and survival. Recently, I2 has been postulated as an immune modulator that depending on the cellular context, can function as an inhibitor or activator of immune responses. We propose that the intake of molecular iodine is increased in adults to at least 1 mg/day in specific pathologies to obtain the potential extrathyroid benefits described in this review.

Hand hygiene for the prevention of infections in neonates

BACKGROUND

Annually, infections contribute to approximately 25% of the 2.8 million neonatal deaths worldwide. Over 95% of sepsis-related neonatal deaths occur in low- and middle-income countries. Hand hygiene is an inexpensive and cost-effective method of preventing infection in neonates, making it an affordable and practicable intervention in low- and middle-income settings. Therefore, hand hygiene practices may hold strong prospects for reducing the occurrence of infection and infection-related neonatal death.

OBJECTIVES

To determine the effectiveness of different hand hygiene agents for preventing neonatal infection in community and health facility settings.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5), in the Cochrane Library; MEDLINE via PubMed (1966 to 10 May 2019); Embase (1980 to 10 May 2019); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 10 May 2019). We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-randomised trials. Searches were updated 1 June 2020.

SELECTION CRITERIA

We included RCTs, cross-over trials, and quasi-RCTs that included pregnant women, mothers, other caregivers, and healthcare workers who received interventions within the community or in health facility settings DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane and the GRADE approach to assess the certainty of evidence. Primary outcomes were incidence of (study author-defined) suspected infection within the first 28 days of life, bacteriologically confirmed infection within the first 28 days of life, all-cause mortality within the first seven days of life (early neonatal death), and all-cause mortality from the 8th to the 28th day of life (late neonatal death).

MAIN RESULTS

Our review included five studies: one RCT, one quasi-RCT, and three cross-over trials with a total of more than 5450 neonates (two studies included all neonates but did not report the actual number of neonates involved). Four studies involved 279 nurses working in neonatal intensive care units and all neonates on admission. The fifth study did not clearly state how many nurses were included in the study. Studies examined the effectiveness of different hand hygiene practices for the incidence of (study author-defined) suspected infection within the first 28 days of life. Two studies were rated as low risk for selection bias, another two were rated as high risk, and one study was rated as unclear risk. One study was rated as low risk for allocation bias, and four were rated as high risk. Only one of the five studies was rated as low risk for performance bias. 4% chlorhexidine gluconate (CHG) compared to plain liquid soap We are uncertain whether plain soap is better than 4% chlorhexidine gluconate (CHG) for nurses' skin based on very low-certainty evidence (mean difference (MD) -1.75, 95% confidence interval (CI) -3.31 to -0.19; 16 participants, 1 study; very low-certainty evidence). We identified no studies that reported on other outcomes for this comparison. 4% chlorhexidine gluconate compared to triclosan 1% One study compared 1% w/v triclosan with 4% chlorhexidine gluconate and suggests that 1% w/v triclosan may reduce the incidence of suspected infection (risk ratio (RR) 1.04, 95% CI 0.19 to 5.60; 1916 participants, 1 study; very low-certainty evidence). There may be fewer cases of infection in the 1% w/v triclosan group compared to the 4% chlorhexidine gluconate group (RR 6.01, 95% CI 3.56 to 10.14; 1916 participants, 1 study; very low-certainty evidence); however, we are uncertain of the available evidence. We identified no study that reported on all-cause mortality, duration of hospital stay, and adverse events for this comparison. 2% CHG compared to alcohol hand sanitiser (61% alcohol and emollients) We are uncertain whether 2% chlorhexidine gluconate reduces the risk of all infection in neonates compared to 61% alcohol hand sanitiser with regards to the incidence of all bacteriologically confirmed infection within the first 28 days of life (RR 2.19, 95% CI 1.79 to 2.69; 2932 participants, 1 study; very low-certainty evidence) in the 2% chlorhexidine gluconate group, but the evidence is very uncertain.   The adverse outcome was reported as mean visual scoring on the skin. There may be little to no difference between the effects of 2% CHG on nurses' skin compared to alcohol hand sanitiser based on very low-certainty evidence (MD 0.80, 95% CI 0.01 to 1.59; 118 participants, 1 study; very low-certainty evidence). We identified no study that reported on all-cause mortality and other outcomes for this comparison. None of the included studies assessed all-cause mortality within the first seven days of life nor duration of hospital stay.  AUTHORS' CONCLUSIONS: We are uncertain as to the superiority of one hand hygiene agent over another because this review included very few studies with very serious study limitations.

Removal of Aerosolized Contaminants from Working Canines via a Field Wipe-Down Procedure

Evidence-based canine decontamination protocols are underrepresented in the veterinary literature. Aerosolized microbiological and chemical contaminants can pose a risk in deployment environments highlighting the need for improved canine field decontamination strategies. Prior work has established the efficacy of traditional, water-intensive methods on contaminant removal from the coat of the working canine; however, it is not known if similar reductions can be achieved with simple field expedient methods when resources are limited. The objective of this study was to measure the reduction of aerosolized contamination via a practical "wipe-down" procedure performed on working canine coats contaminated with a fluorescent, non-toxic, water-based aerosol. Disposable, lint-free towels were saturated with one of three treatments: water, 2% chlorhexidine gluconate scrub (CHX), or 7.5% povidone-iodine scrub (PVD). Both CHX and PVD were diluted at a 1:4 ratio. Treatments were randomly assigned to one of three quadrants established across the shoulders and back of commonly utilized working dog breeds (Labrador retrievers, n = 16; German shepherds, n = 16). The fourth quadrant remained unwiped, thus serving as a control. Reduction in fluorescent marker contamination was measured and compared across all quadrants. PVD demonstrated greater marker reduction compared to CHX or water in both breeds (p < 0.0001). Reduction was similar between CHX or water in Labradors (p = 0.86) and shepherds (p = 0.06). Effective wipe-down strategies using common veterinary cleansers should be further investigated and incorporated into decontamination practices to safeguard working canine health and prevent cross-contamination of human personnel working with these animals.

Biocompatible MOF-808 as an iodophor antimicrobial agent with controlled and sustained release of iodine

I2@MOF-808 was prepared to investigate the amount of I2 adsorbed on MOF-808. By antibacterial tests, it was also confirmed that it could be considered as a biocide without the problem of microbial resistance and instability of iodine.

Validation of Three Different Sterilization Methods of Tilapia Skin Dressing: Impact on Microbiological Enumeration and Collagen Content

Tilapia fish skin has demonstrated promise as a stable and practical biological dressing to be used in wound and burn management. However, the appropriate sterilization technique of the Tilapia fish skin is crucial before its clinical application. The standard sterilization technique must eliminate harmful pathogens but maintain the structural and biochemical properties that could compromise the dressing function. This study investigated and compared the efficiency of three sterilizing agents; chlorhexidine gluconate 4% (CHG), povidone iodine 10% (PVP-I), and silver nanoparticles (25 μg/mL) (AgNPs), at three different times (5, 10, and 15 min) on Tilapia fish skin based on the microbial count, histological and collagen properties. Among the sterilization procedures, AgNPs showed rapid and complete antimicrobial activity, with a 100% reduction in microbial growth of the fish skin throughout the treated times. Furthermore, AgNPs did not impair the cellular structure or collagen fibers content of the fish skin. However, CHG and PVP-I caused alterations in the collagen content. This study demonstrated that the AgNPs treatment of Tilapia fish skin provided sterile skin while preserving the histological properties and structural integrity. These findings provide an efficient and quick sterilization method suitable for Tilapia fish skin that could be adopted as a biological dressing.

Prevention of Periprosthetic Joint Infection (PJI): A Clinical Practice Protocol in High-Risk Patients

Background: Periprosthetic joint infection (PJI) represents 25% of failed total knee arthroplasties (TKA). The European Knee Associates (EKA) formed a transatlantic panel of experts to perform a literature review examining patient-related risk factors with the objective of producing perioperative recommendations in PJI high-risk patients. Methods: Multiple databases (Pubmed/MEDLINE, EMBASE, Scopus, Cochrane Library) and recommendations on TKA PJI prevention measures from the International Consensus Meetings on PJI from the AAOS and AAHKS were reviewed. This represents a Level IV study. Results: Strong evidence was found on poor glycemic control, obesity, malnutrition, and smoking being all associated with increased rates of PJI. In the preoperative period, patient optimization is key: BMI < 35, diet optimization, Hemoglobin A1c < 7.5, Fructosamine < 292 mmol/L, smoking cessation, and MRSA nasal screening all showed strong evidence on reducing PJI risk. Intraoperatively, a weight-based antibiotic prophylaxis, accurate fluid resuscitation, betadine and chlorhexidine dual skin preparation, diluted povidone iodine solution irrigation, tranexamic acid administration, and monofilament barbed triclosan-coated sutures for soft tissues closure all represented effective prevention measures. In the postoperative period, failure to reach normalization of ESR, CRP, D-dimer, and IL-6 six weeks postoperatively suggested early PJI. Conclusion: The current recommendations from this group of experts, based on published evidence, support risk stratification to identify high-risk patients requiring implementation of perioperative measures to reduce postoperative PJI.

Hypoxia, hypotension, and bradycardia induced by povidone-iodine ingestion: A pediatric case report and literature review

Povidone-iodine (PI) is a disinfectant and antiseptic agent commonly used to sterilize skin, mucous membranes, and wounds. PI intoxication is very rare, but the complications may be severe. We report a pediatric patient who presented in the emergency department with hypoxia, hypotension, and bradycardia after unintentional PI ingestion.

The Effect of Anti-Amoebic Agents and Ce6-PDT on Acanthamoeba castellanii Trophozoites and Cysts, In Vitro

Purpose

The purpose of this study was to analyze the concentration-dependent effects of biguanides (polyhexamethylene biguanide [PHMB], chlorhexidine [CH]); diamidines (hexamidine-diisethionate [HD], propamidine-isethionate [PD], dibromopropamidine-diisethionate [DD]); natamycin (NM); miltefosine (MF); povidone iodine (PVPI), and chlorin e6 PDT on Acanthamoeba trophozoites and cysts, in vitro.

Methods

Strain 1BU was cultured in peptone-yeast extract-glucose medium. Trophozoites or cysts were cultured in PYG medium containing each agent at 100%, 50%, and 25% of maximum concentration for 2 hours. The percentage of dead trophozoites was determined using a non-radioactive cytotoxicity assay and trypan blue staining. Treated cysts were also maintained on non-nutrient agar Escherichia coli (E. coli) plates and observed for 3 weeks.

Results

All tested drugs displayed significant cytotoxic effects on 1BU cells based on the biochemical and staining-based viability assays tested. On non-nutrient agar E. coli plates, neither trophozoites nor freshly formed cysts were observed after PHMB, PD, NM, and PVPI treatment, respectively, within 3 weeks. However, CH-, HD-, DD-, and MF-treated cysts could excyst, multiply, and encyst again.

Conclusions

The off-label drugs PHMB, PD, NM, and PVPI are under in vitro conditions more effective against strain 1BU than CH, HD, DD, and MF. Our findings also suggest that the non-nutrient agar E. coli plate assay should be considered as method of choice for the in vitro analysis of the treatment efficacy of anti-amoebic agents.

Translational Relevance

Ophthalmologists may optimize the treatment regime against Acanthamoeba keratitis by pre-testing the in vitro susceptibilities of the Acanthamoeba strain against drugs of interest with the non-nutrient E. coli agar plate assay.

Optimal Management of Allergic Fungal Rhinosinusitis

Introduction

Allergic fungal rhinosinusitis (AFRS) is a chronic disorder with significant morbidity and a high recurrence rate needing long-term follow-up. Even after its first description many decades ago, there is still considerable uncertainty about the management of this condition.

Description

In this chapter, we breakdown the topic “Optimal management of allergic fungal rhinosinusitis” into sub-headings in order to discuss the latest research and available literature under each topic in great detail. Every attempt has been made to incorporate the highest level of evidence that was available at the time of writing.

Summary

Pre-operative diagnosis and further management prior to surgery is important. Steroids help in reducing inflammation and help improve the surgical field. Surgery remains the mainstay in the management of this condition along with long-term medical management. Oral steroids are reserved for acute flare-ups in the background of associated lung concerns. Oral and topical antifungal agents have no role in the control of the disease. Biological agents are being prescribed predominantly by respiratory physician colleagues, mainly for the control of the chest-related issues rather than for sinus disease. Immunotherapy as an adjunct with surgery is promising.

Conclusion

AFRS is a disease with many variables and a wide range of symptomatic presentation. It takes a keen clinician to identify the disease and subsequently manage the condition. Treatment involves long-term follow-up with early detection of recurrence or flare-ups. Any of the mentioned modalities of management may be employed to effectively control the condition, and treatment protocols will have to be tailor-made to suit each individual patient. Various medications and drugs such as Manuka honey, antimicrobial photodynamic therapy, hydrogen peroxide and betadine rinses appear to be promising. More robust studies need to be undertaken to ascertain their routine use in clinical practice.

Povidone Iodine: Properties, Mechanisms of Action, and Role in Infection Control and Staphylococcus aureus Decolonization

Nasal decolonization is an integral part of the strategies used to control and prevent the spread of methicillin-resistant Staphylococcus aureus (MRSA) infections. The two most commonly used agents for decolonization are intranasal mupirocin 2% ointment and chlorhexidine wash, but the increasing emergence of resistance and treatment failure has underscored the need for alternative therapies. This article discusses povidone iodine (PVP-I) as an alternative decolonization agent and is based on literature reviewed during an expert's workshop on resistance and MRSA decolonization. Compared to chlorhexidine and mupirocin, respectively, PVP-I 10 and 7.5% solutions demonstrated rapid and superior bactericidal activity against MRSA in in vitro and ex vivo studies. Notably, PVP-I 10 and 5% solutions were also active against both chlorhexidine-resistant and mupirocin-resistant strains, respectively. Unlike chlorhexidine and mupirocin, available reports have not observed a link between PVP-I and the induction of bacterial resistance or cross-resistance to antiseptics and antibiotics. These preclinical findings also translate into clinical decolonization, where intranasal PVP-I significantly improved the efficacy of chlorhexidine wash and was as effective as mupirocin in reducing surgical site infection in orthopedic surgery. Overall, these qualities of PVP-I make it a useful alternative decolonizing agent for the prevention of S. aureus infections, but additional experimental and clinical data are required to further evaluate the use of PVP-I in this setting.

Parameter control and property analysis in the preparation of platinum iodide nanocolloids through the electrical spark discharge method

This study employed the electrical spark discharge method to prepare platinum iodide nanocolloids at normal temperature and pressure. Wires composed of 99.5% platinum were applied as the electrodes, and 250 ppm liquid iodine was employed as the dielectric fluid. An electric discharge machine was applied to generate cyclic direct current pulse power between the electrodes. Five sets of turn-on and turn-off time (T on-T off) parameters, namely 10-10, 30-30, 50-50, 70-70, and 90-90 μs, were implemented to identify the optimal nanocolloid preparation conditions. An ultraviolet-visible spectroscope, a Zetasizer, and a transmission electron microscope were used to examine the nanocolloids' properties. The results revealed that the T on-T off parameter set of 10-10 μs was the most ideal setting for platinum iodide nanocolloid preparation. With this parameter set, the characteristic wavelengths of the nanocolloid were 285 and 350 nm, respectively; its absorbance values were 0.481 and 0.425, respectively; and its zeta potential and particle size were -30.3 mV and 61.88 nm, respectively. This parameter set yielded maximized absorbance, satisfactory suspension stability, and minimized nanoparticle sizes for the nanocolloid.

Virucidal benefits of povidone-iodine use on the ocular surface: a review

Povidone-iodine (PVI) preparations are well known for their microbicidal effect. In ophthalmology, PVI is commonly used to sterilise the ocular surface prior to surgical procedures. It is also used uncommonly as treatment for adenoviral conjunctivitis, yet the virucidal benefits of PVI have not been clearly documented in existing clinical management guidelines for ocular surface conditions. The COVID-19 pandemic, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, has challenged traditional healthcare systems. The morbidity and mortality of this highly contagious disease have resulted in fatalities among healthcare workers, including ophthalmologists. The SARS-CoV-2 virus has been identified on conjunctival testing, a potential source of contagious infection which may be unrecognised in asymptomatic carriers. Concern has been raised that ocular procedures may be ‘aerosol-generating’ and the additional wearing of personal protective equipment has been recommended to protect operating theatre staff. This literature review demonstrates that PVI has a broad virucidal activity, including against coronaviruses. It is already used perioperatively as standard of ophthalmic care and has been shown clinically to be effective against adenoviruses on the ocular surface. The current surgical practice of application of 5%–10% PVI applied periocularly for 3 min seems to provide an adequate effective reduction in the patient’s ocular surface viral load. The virucidal benefits of routine PVI use should be included in ophthalmology guidelines regarding safe ocular surgery protocols.

Randomized clinical trial evaluating the effect of bandaging on the healing of sole ulcers in dairy cattle

This randomized clinical trial investigated the effect of bandaging on 56 uncomplicated sole ulcers (SU) among a sample of 52 dairy cows. Following therapeutic hoof trimming and povidone-iodine treatment, all cows received a wooden block on the unaffected claw and were randomly assigned into either a bandaged or non-bandaged group. The bandaging process was standardized and applied by the same veterinarian. Wound size and locomotion were measured weekly. Overall, 19 of 32 SU (59.4%) in the non-bandaged group were healed at week 4 compared to 7 of 24 ulcers (29.2%) in the bandaged group. Healing was significantly higher for non-bandaged than bandaged SU (P = 0.024). Bandaging had no effect on locomotion (P = 0.9). Cows with a lower locomotion (Sprecher 1 + 2) had significantly smaller lesion sizes (median lesion size, 0.5 cm², IQR = 0.21 to 0.92 cm²) than animals with locomotion score 3-5 (median lesion size, 0.9 cm², IQR = 0.42 to 1.81 cm²; P < 0.001). A multivariate cox proportional hazard regression indicated that bandaging and parity had a significant effect on healing. Specifically, bandaged SU had a significantly lower hazard ratio (HR) to cure compared to non-bandaged SU (HR = 0.32; P = 0.01; 95% CI = 0.13 to 0.78). Furthermore, cows with parity ≥3 had a significantly higher HR to cure compared to cows in their first lactation (HR = 2.73; P = 0.025; 95% CI = 1.14 to 6.56).

A polymer-based anti-quorum catheter coating to challenge MDR Staphylococcus aureus: in vivo and in vitro approaches

BACKGROUND

MDR Staphylococcus aureus is a major aetiological agent of catheter-associated infections. A quorum sensing targeted drug development approach proves to be an effective alternative strategy to combat such infections.

METHODS

Intravenous catheters were coated with polymethacrylate copolymers loaded with the antivirulent compound 2-[(methylamino)methyl]phenol (2MAMP). The in vitro drug release profile and kinetics were established. The anti-biofilm effect of the coated catheters was tested against clinical isolates of MDR S. aureus. The in vivo studies were carried out using adult male Wistar rats by implanting coated catheters in subcutaneous pockets. Histopathological analysis was done to understand the immunological reactions induced by 2MAMP.

RESULTS

A uniform catheter coating of thickness 0.1 mm was achieved with linear sustained release of 2MAMP for 6 h. The coating formulation was cytocompatible. The in vitro and in vivo anti-adherence studies showed reduced bacterial accumulation in coated catheters after 48 h. The histopathological results confirmed that the coated catheter did not bring about any adverse inflammatory response.

CONCLUSIONS

The developed anti-quorum-coated catheter that is non-toxic and biocompatible has the potential to be used in other medical devices, thereby preventing catheter-associated infections.

Intrauterine infusion of povidone-iodine: Its effect on the endometrium and subsequent fertility in postpartum dairy cows

This study aimed to describe the duration of inflammation after intrauterine infusion of polyvinylpyrrolidone-iodine (povidone-iodine, PVP-I), determine the effect of PVP-I infusion on the subsequent fertility, and evaluate the histopathology of the endometrium in dairy cows. In Experiment 1, 120 lactating clinically healthy Holstein-Friesian cows at 5 weeks postpartum (W5) were equally divided into three groups: intrauterine infusion of 2% PVP-I (PVP), saline (SAL), and no treatment (NTX). Endometrial cytology was performed daily from D0 (W5) to D7 to determine the percentage of polymorphonuclear cells (PMN%) in 44 of the 120 cows. All cows received timed artificial insemination at D17. In Experiment 2, 25 cows were randomly classified into sacrifice at 24 hr or 48 hr after 2% PVP-I infusion (PVP24 and PVP48), and 24, 48, 72, or 96 hr after SAL infusion (SAL24; SAL48; SAL72; SAL96), or no treatment (NTX). Histopathology was performed on the uterus of each cow. In Experiment 1, PMN% was greater in PVP (P<0.05) than in SAL and NTX, on D1, but decreased to a level similar to that of the other groups by D2. Conception rate was higher (P<0.05) in PVP cows compared to SAL and NTX cows. In Experiment 2, stratified columnar epithelium in the uterus disappeared in PVP24 and SAL24. The epithelium was regenerated in PVP48, SAL72, and SAL96, but not in SAL48. In conclusion, the results of the study suggest that PVP-I induces transient uterine inflammation, promotes regeneration of endometrial epithelial cells and improves fertility.

Surgical wound infection caused by a multi drug resistant Streptococcus pneumoniae Serotype 19A after a total coloproctectomy with ileostomy

Streptococcus pneumoniae (S. pneumoniae) colonizes asymptomatically the human nasopharynx. This pathogen is responsible for sinusitis, otitis media, pneumonia, bacteremia and meningitis. We report the case of a 35-year-old female patient who developed a surgical wound infection by a multi drug resistant S. pneumoniae serotype 19A after a total coloprotectomy. This first found in Morocco shows the implication of multidrug resistant S. pneumoniae in surgical wound infections.

A review of iodine-based compounds, with a focus on biofilms: results of an expert panel

Biofilms play a central role in the chronicity of non-healing lesions such as venous leg ulcers and diabetic foot ulcers. Therefore, biofilm management and treatment is now considered an essential part of wound care. Many antimicrobial treatments, whether topical or systemic, have been shown to have limited efficacy in the treatment of biofilm phenotypes. The antimicrobial properties of iodine compounds rely on multiple and diverse interactions to exert their effects on microorganisms. An expert panel, held in Las Vegas during the autumn Symposium on Advanced Wound Care meeting in 2018, discussed these properties, with the focus on iodine and iodophors and their effects on biofilm prevention and treatment.

Effects of povidone-iodine composite on the elimination of bacterial biofilm

BACKGROUND

Povidone-iodine (PVP-I) is well known as an antiseptic and exhibits extensive activity against various pathogens. However, due to its uniquely unpleasant nature, it cannot be used locally to deactivate various sinonasal pathogens. Therefore, we developed a PVP-I composite that blocks the unpleasant odor of PVP-I for use as a local antiseptic in the sinonasal cavity and evaluated its effect on bacterial biofilm's formation and elimination in in vivo and in vitro models.

METHODS

MTT, lactate dehydrogenase, and live/dead staining assay were performed to examine the cellular toxicity of PVP-I composites on the primary human nasal epithelial and RPMI 2650 cells. Crystal violet assay was performed to quantify bacterial biofilm after treating with various agents, including PVP-I and antibiotics. Hematoxylin-and-eosin staining, live/dead staining assay, and scanning electron microscopy were conducted to evaluate the effect of PVP-I on biofilm formation in a mice biofilm model.

RESULTS

It was observed that the PVP-I composite did not have any significant toxic effect on the nasal epithelial cells. Furthermore, the PVP-I composite effectively inhibited the formation of bacterial biomass within a dose-dependent manner after 48 hours of incubation with Pseudomonas aeruginosa and Staphylococcus aureus. In mice, it effectively eliminated biofilm from the mucosa of the nasal cavity and maxillary sinus at the tested concentrations.

CONCLUSION

The results of this study indicate that the PVP-I composite is a promising compound that could be used locally to prevent the formation of biofilms and to eliminate them from the sinonasal cavity.

Povidone-iodine Does Not Affect Acellular Dermal Matrix Integration in Patients Undergoing 2-staged, Prepectoral, Breast Reconstructive Surgery

Background:

Povidone-iodine has been traditionally used as an antimicrobial agent to irrigate the breast pocket and rinse the prosthesis before placement in the pocket. Use of povidone-iodine with breast implants was banned from 2000 to 2017. During this period, acellular dermal matrix (ADM) was introduced to breast surgery. In nonclinical studies, povidone-iodine can impair collagen synthesis and kill fibroblasts. Cellular repopulation was critical for ADM integration. Whether povidone-iodine impacts ADM integration was unknown.

Methods:

Patients who underwent immediate, prepectoral, 2-staged breast reconstruction were included in this retrospective study. Study population was divided into povidone-iodine–treated patients and triple-antibiotic–treated patients. The breast pockets were rinsed with the antimicrobial agent, and the prostheses and ADMs were presoaked in the agent perioperatively. At implant exchange, the extent of ADM integration was clinically assessed. ADM integration was defined as >25% of matrix vascularization. ADM integration and postoperative complications were compared between the groups.

Results:

A total of 111 patients (257 reconstructions) were included—58 patients (111 reconstructions) were exposed to povidone-iodine and 53 patients (97 reconstructions) to triple-antibiotic solution. ADM integration was noted in 97% of breasts in each group. Integrated matrices appeared healthy, had no signs of foreign body reaction, and demonstrated punctate bleeding. Complications did not differ between the groups, including the rate of infections, seroma, and expander loss.

Conclusion:

Irrigation of the breast pocket and presoaking of the prosthesis and ADM with povidone-iodine appear to have no adverse consequences on clinical outcomes and did not impede matrix integration.

Lignin-mediated green synthesis of AgNPs in carrageenan matrix for wound dressing applications

Carrageenan-based functional wound dressing materials were prepared through a one-pot green synthesis of silver nanoparticles (AgNPs) using lignin as a reducing and capping agent in the carrageenan matrix cross-linked with divalent cations such as CaCl₂, CuCl₂, and MgCl₂. The wound healing efficacy of the hydrogel film was evaluated using Sprague-Dawley rats. Crosslinking with divalent cations improved the physical properties of carrageenan-based hydrogels containing AgNPs such as strength, flexibility, swelling ratio, and release rate of Ag ions depending on the type of crosslinking agent used. The carrageenan-based hydrogels were biocompatible against the mouse fibroblast cell line (L929 cell line). Carra/Lig/AgNPs/MgCl₂ hydrogel significantly healed the wounds in Sprague-Dawley rats within two weeks, reducing the wound area to <3%, which was further confirmed by histological analysis with the epidermis and mature glands. Carrageenan-based multifunctional hydrogels have a high potential for wound dressing applications.

Is There a Role for Preclosure Dilute Betadine Irrigation in the Prevention of Postoperative Infection Following Total Joint Arthroplasty?

BACKGROUND

Conflicting evidence exists surrounding the use of preclosure irrigation solutions in primary total joint arthroplasty (TJA). We aimed to determine the role of dilute betadine lavage in preventing early infection after primary TJA.

METHODS

We retrospectively reviewed primary TJAs between 2010 and 2018. Dilute betadine lavage was introduced to our practice in November 2014. We included 3513 total hip arthroplasties, 3932 total knee arthroplasties, and 1033 hip resurfacings (HRs). In group 1 (n = 5588), surgical wounds were irrigated with saline; group 2 used dilute betadine solution (n = 2890). Subanalyses using propensity matching based on known risk factors of infection-age, body mass index, American Society of Anesthesiologists grade, diabetes, and procedure-were completed.

RESULTS

There were 48 acute infections in group 1 (0.9%) and 23 in group 2 (0.8%) (P = .762). HR without betadine had the highest acute infection prevalence (P = .028). When groups in the whole cohort were propensity score-matched, group 1 had more acute infections than group 2 (P = .033). The effect of betadine was isolated to HR patients. After excluding HR cases, betadine continued to reduce the acute infection rate when compared with the no betadine group, but this was not statistically significant (0.4% vs 0.8%; P = .101). Likewise, we did not find a significant difference in total hip arthroplasty and total knee arthroplasty patients (P = .796).

CONCLUSION

There was a decreased infection rate in the betadine group overall when groups were propensity-matched. Because the reduction in the acute infection rate was clinically significant, we feel this practice is an effective means to prevent infections.