Interleukin-6 concentrations in wound fluids rather than serological markers are useful in assessing bacterial triggers of ulcer inflammation

Inflammatory Profile Associated with Secondary Infection from Bothrops atrox Snakebites in the Brazilian Amazon

Bothrops snakebite envenomation (SBE) is consider an important health problem in Brazil, where Bothrops atrox is mainly responsible in the Brazilian Amazon. Local effects represent a relevant clinical issue, in which inflammatory signs and symptoms in the bite site represent a potential risk for short and long-term disabilities. Among local complications, secondary infections (SIs) are a common clinical finding during Bothrops atrox SBE and are described by the appearance of signs such as abscess, cellulitis or necrotizing fasciitis in the affected site. However, the influence of SI in the local events is still poorly understood. Therefore, the present study describes for the first time the impact of SBE wound infection on local manifestations and inflammatory response from patients of Bothrops atrox SBE in the Brazilian Amazon. This was an observational study carried out at the Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus (Brazil), involving victims of Bothrops SBE. Clinical and laboratorial data were collected along with blood samples for the quantification of circulating cytokines and chemokines before antivenom administrations (T0) and 24 h (T1), 48 h (T2), 72 h (T3) and 7 days after (T4). From the 94 patients included in this study, 42 presented SI (44.7%) and 52 were without SI (NSI, 55.3%). Patients classified as moderate envenoming presented an increased risk of developing SI (OR = 2.69; CI 95% = 1.08-6.66, p = 0.033), while patients with bites in hands showed a lower risk (OR = 0.20; CI 95% = 0.04-0.96, p = 0.045). During follow-up, SI patients presented a worsening of local temperature along with a sustained profile of edema and pain, while NSI patients showed a tendency to restore and were highlighted in patients where SI was diagnosed at T2. As for laboratorial parameters, leukocytes, erythrocyte sedimentation ratio, fibrinogen and C-reactive protein were found increased in patients with SI and more frequently in patients diagnosed with SI at T3. Higher levels of circulating IL-2, IL-10, IL-6, TNF, INF-γ and CXCL-10 were observed in SI patients along with marked correlations between these mediators and IL-4 and IL-17, showing a plurality in the profile with a mix of Th1/Th2/Th17 response. The present study reports for the first time the synergistic effects of local infection and envenoming on the inflammatory response represented by local manifestations, which reflected on laboratorial parameters and inflammatory mediators and thus help improve the clinical management of SI associated to Bothrops SBE.

Zamzam Water Ameliorates Gentamicin-Induced Testicular Toxicity in a Rat Model via Targeting Sperm Parameters, Testicular Tissue Oxidative Insult, Inflammation, Apoptosis, and Pituitary-Gonadal Axis

Gentamicin is considered one of the most typical causes of testicular damage. Oxidative stress is a significant contributor to testicular tissue damage. Zamzam water (alkaline in nature) has an antioxidant effect. The purpose of this study was to assess the potential palliative effect of Zamzam water against gentamicin-induced testicular damage. Thirty Rats were separated into three groups, each with ten rats, as follows: The Control received only normal saline. The gentamicin group received 100 mg/kg/day of gentamicin intraperitoneally for six days from day 15 to the end of the experiment. The gentamicin +Zamzam Water group received a dose of gentamicin 100 mg/kg/day intraperitoneally with Zamzam water as their sole source of drinking from day one to day 21. Hormonal assay in serum, histological, immunohistochemical, and ultrastructural examination of testicular tissue with a molecular study were obtained. Pretreatment with Zamzam water significantly p < 0.001 increased serum levels of testosterone, FSH, and LH, as well as the percentage of sperm motility and progressive motility. It also upregulated SOD, CAT, GPx enzymatic activity, gene expression of Nrf2/HO-1, and immunoexpression of PCNA. While the percentage of dead sperm and abnormal sperm, immunoexpression of NFκB, Caspase 3, inflammatory cytokines TNFα, IL-1β, IL-6, and MDA levels significantly (p < 0.001) declined with histological improvement. It was concluded that Zamzam water as alkaline water possesses antioxidant, anti-inflammatory, and antiapoptotic effects against gentamicin-induced testicular toxicity in vivo.

Homocysteine and Inflammatory Cytokines in the Clinical Assessment of Infection in Venous Leg Ulcers

Inflammation and biofilm-associated infection are common in chronic venous leg ulcers (VU), causing deep pain and delayed healing. Albeit important, clinical markers and laboratory parameters for identifying and monitoring persistent VU infections are limited. This study analyzed 101 patients with infected (IVU) and noninfected VUs (NVU). Clinical data were collected in both groups. The serum homocysteine (Hcys) and inflammatory cytokines from the wound fluid were measured. In addition, microbial identification, antibiotic susceptibility, and biofilm production were examined. IVU were 56 (55.4%) while NVU were 45 (44.5%). IVUs showed a significant increase in the wound's size and depth compared to NVUs. In addition, significantly higher levels of interleukin (IL)-6, IL-10, IL17A, and tumor necrosis factor-alpha (TNF-α) were found in patients with IVUs compared to those with NVUs. Notably, hyperhomocysteinemia (HHcy) was significantly more common in patients with IVUs than NVUs. A total of 89 different pathogens were identified from 56 IVUs. Gram-negative bacteria were 51.7%, while the Gram-positives were 48.3%. At the species level, Staphylococcus aureus was the most common isolate (43.8%), followed by Pseudomonas aeruginosa (18.0%). Multidrug-resistant organisms (MDROs) accounted for 25.8% of the total isolates. Strong biofilm producers (SBPs) (70.8%) were significantly more abundant than weak biofilm producers (WBP) (29.2%) in IVUs. SBPs were present in 97.7% of the IVUs as single or multispecies infections. Specifically, SBPs were 94.9% for S. aureus, 87.5% for P. aeruginosa, and 28.6% for Escherichia coli. In IVU, the tissue microenvironment and biofilm production can support chronic microbial persistence and a most severe clinical outcome even in the presence of an intense immune response, as shown by the high levels of inflammatory molecules. The measurement of local cytokines in combination with systemic homocysteine may offer a novel set of biomarkers for the clinical assessment of IVUs caused by biofilm-producing bacteria.

Physical characterization and wound healing properties of Zamzam water

The objective of the study was to evaluate the quality of Zamzam water, holy water for Muslims and consumed for its medicinal value. The present study demonstrates the physicochemical characterization and wound healing property of Zamzam water. The physicochemical characterization of Zamzam water samples was analyzed for dissolved oxygen, pH, conductivity, total dissolved solids, redox potential, zeta potential, polydispersity index, and zeta size. The microbial quality of Zamzam water was also assessed by exposing water samples to open air. In this work, Zamzam water was also screened for the medicinal value through wound healing properties in Wistar rats. Zamzam water exhibited a unique physicochemical characterization with high levels of dissolved oxygen, zeta potential, polydispersity index, redox potential, total dissolved solids, and conductivity before exposure to open air. After open air exposure, Zamzam water resisted the growth of bacteria. The wound healing properties of Zamzam water in vivo showed a 96% of healing effect on 12th day observation. The wound healing was achieved by modulating pro-inflammatory cytokine such as interleukin -1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor -α (TNF-α). Followed by the level of apoptosis markers caspase-9 and caspase-3 were reduced. The present study proved that Zamzam water is a good-quality water and showed excellent wound healing property. Therefore, Zamzam water can be used for pharmaceutical formulations.

Cytokines and Venous Leg Ulcer Healing-A Systematic Review

Venous leg ulcers (VLUs) are the most common type of leg ulcers with a significant socioeconomic burden due to slow healing. Cytokines may be involved in the pathogenesis of VLUs. In this systematic review, our objective was to investigate the association between cytokine levels, including growth factors, with the healing of VLUs. PubMed, Embase, Web of Science and Cochrane Library were searched from their inception to August 2021. We retrieved 28 articles investigating 38 different cytokines in 790 patients. Cytokines were most commonly investigated in wound fluid and less frequently in biopsies and serum. The studies were judged as having a moderate to high risk of bias, and the results were often inconsistent and sometimes conflicting. A meta-analysis was not performed due to clinical and methodological heterogeneities. We found weak evidence for elevated IL-1α, IL-6, IL-8, TNF-α and VEGF levels in non-healing VLUs, an elevation that declined with healing. TGF-β1 levels tended to increase with VLU healing. Other cytokines warranting further investigations include EGF, FGF-2, GM-CSF, IL-1β, IL-1Ra and PDGF-AA/PDGF-BB. We conclude that non-healing VLUs may be associated with an elevation of a palette of pro-inflammatory cytokines, possibly reflecting activated innate immunity in these wounds. There is a paucity of reliable longitudinal studies monitoring the dynamic changes in cytokine levels during wound healing.

Wound-healing and cytokine-modulating potential of medicinal oil formulation comprising leaf extract of Murraya koenigii and olive oil

The study investigated the wound healing effect of medicinal oil (MO) formulation prepared from Murraya koenigii leaves extract (methanolic) incorporated in olive oil. The MO was visually transparent, homogenous, smooth in texture, the viscosity grade was observed as 140 cP and easily spreadable. Pro-inflammatory cytokines IL-1β, IL-6, and TNF-α were significantly reduced to 82.3 ± 3.5, 156 ± 6.2, 137.3. ± 5.5 pg/ml, respectively after treatment with MO when compared to disease control animals that showed IL-1β, IL-6, and TNF-α levels of 170 ± 6, 265 ± 7, and 288.6 ± 11, pg/ml respectively. The level of pro-inflammatory cytokine in povidone iodine solution (PIS) group was 95.3 ± 3, 162 ± 6, 177.6 ± 8.9 pg/ml of IL-1β, IL-6, and TNF-α respectively. Interestingly, the wound-healing efficacy of MO was found better as compared to povidone iodine treated standard group and concluded that MO has excellent wound healing effect.

Wound fluid sampling methods for proteomic studies: A scoping review

Understanding why some wounds are hard to heal is important for improving care and developing more effective treatments. The method of sample collection used is an integral step in the research process and thus may affect the results obtained. The primary objective of this study was to summarise and map the methods currently used to sample wound fluid for protein profiling and analysis. Eligible studies were those that used a sampling method to collect wound fluid from any human wound for analysis of proteins. A search for eligible studies was performed using MEDLINE, Embase and CINAHL Plus in May 2020. All references were screened for eligibility by one reviewer, followed by discussion and consensus with a second reviewer. Quantitative data were mapped and visualised using appropriate software and summarised via a narrative summary. After screening, 280 studies were included in this review. The most commonly used group of wound fluid collection methods were vacuum, drainage or use of other external devices, with surgical wounds being the most common sample source. Other frequently used collection methods were extraction from absorbent materials, collection beneath an occlusive dressing and direct collection of wound fluid. This scoping review highlights the variety of methods used for wound fluid collection. Many studies had small sample sizes and short sample collection periods; these weaknesses have hampered the discovery and validation of novel biomarkers. Future research should aim to assess the reproducibility and feasibility of sampling and analytical methods for use in larger longitudinal studies.

Microbiological Status of Venous Leg Ulcers and Its Predictors: A Single-Center Cross-Sectional Study

Venous leg ulcers are frequently colonized by microbes. This can be particularly devastating if the ulcer is infected with alert pathogens, i.e., highly virulent microorganisms with well-developed mechanisms of antibiotic resistance. We analyzed the microbiological status of venous leg ulcers and identified the clinicodemographic predictors of culture-positive ulcers, especially in ulcers with colonization by alert pathogens.

METHODS

This study included 754 patients with chronic venous leg ulcers. Material for microbiological analysis was collected by swabbing only from patients who did not receive any antibiotic treatment.

RESULTS

A total of 636 (84.3%) patients presented with culture-positive ulcers. Alert pathogens, primarily Pseudomonas aeruginosa, were detected in 28.6% of the positive cultures. In a logistic regression model, culture-positive ulcers were predicted independently by age > 65 years, current ulcer duration > 12 months, and ulceration area greater than 8.25 cm². Two of these factors, duration of current ulcer > 12 months and ulceration area > 8.25 cm², were also identified as the independent predictors of colonization by alert pathogens.

CONCLUSIONS

Colonization/infection is particularly likely in older persons with chronic and/or large ulcers. Concomitant atherosclerosis was an independent predictor of culture-negative ulcers.

What Makes Wounds Chronic

Chronic wounds present a unique therapeutic challenge to heal. Chronic wounds are colonized with bacteria and the presence of a biofilm that further inhibits the normal wound healing processes, and are locked into a very damaging proinflammatory response. The treatment of chronic wounds requires a coordinated approach, including debridement of devitalized tissue, minimizing bacteria and biofilm, control of inflammation, and the use of specialized dressings to address the specific aspects of the particular nonhealing ulcer.

It takes two for chronic wounds to heal: dispersing bacterial biofilm and modulating inflammation with dual action plasma coatings

Chronic wounds are affecting increasingly larger portions of the general population and their treatment has essentially remained unchanged for the past century. This lack of progress is due to the complex problem that chronic wounds are simultaneously infected and inflamed. Both aspects need to be addressed together to achieve a better healing outcome. Hence, we hereby demonstrate that the stable nitroxide radical (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) can be plasma polymerized into smooth coatings (TEMPOpp), as seen via atomic force microscopy, X-ray photoelectron spectroscopy and ellipsometry. Upon contact with water, these coatings leach nitroxides into aqueous supernatant, as measured via EPR. We then exploited the known cell-signalling qualities of TEMPO to change the cellular behaviour of bacteria and human cells that come into contact with the surfaces. Specifically, the TEMPOpp coatings not only suppressed biofilm formation of the opportunistic bacterium Staphylococcus epidermidis but also dispersed already formed biofilm in a dose-dependent manner; a crucial aspect in treating chronic wounds that contain bacterial biofilm. Thus the coatings' microbiological efficacy correlated with their thickness and the thickest coating was the most efficient. Furthermore, this dose-dependent effect was mirrored in significant cytokine reduction of activated THP-1 macrophages for the four cytokines TNF-α, IL-1β, IL-6 and IP-10. At the same time, the THP-1 cells retained their ability to adhere and colonize the surfaces, as verified via SEM imaging. Thus, summarily, we have exploited the unique qualities of plasma polymerized TEMPO coatings in targeting both infection and inflammation simultaneously; demonstrating a novel alternative to how chronic wounds could be treated in the future.

We plasma polymerized the stable nitroxide radical TEMPO into thin coatings and exploited the coatings' unique qualities in targeting both infection and inflammation simultaneously; demonstrating a novel alternative as to how chronic wounds could be treated in the future.

Real-time bacterial fluorescence imaging accurately identifies wounds with moderate-to-heavy bacterial burden

OBJECTIVE

Clinical evaluation of signs and symptoms (CSS) of infection is imperative to the diagnostic process. However, patients with heavily colonised and infected wounds are often asymptomatic, leading to poor diagnostic accuracy. Point-of-care fluorescence imaging rapidly provides information on the presence and location of bacteria. This clinical trial (#NCT03540004) aimed to evaluate diagnostic accuracy when bacterial fluorescence imaging was used in combination with CSS for identifying wounds with moderate-to-heavy bacterial loads.

METHODS

Wounds were assessed by study clinicians using NERDS and STONEES CSS criteria to determine the presence or absence of moderate-to-heavy bacterial loads, after which the clinician prescribed and reported a detailed treatment plan. Only then were fluorescence images of the wound acquired, bacterial fluorescence determined to be present or absent and treatment plan adjusted if necessary.

RESULTS

We examined 17 VLUs/2 DFUs. Compared with CSS alone, use of bacterial fluorescence imaging in combination with CSS significantly improved sensitivity (22% versus 72%) and accuracy (26% versus 74%) for identifying wounds with moderate-to-heavy bacterial loads (≥10⁴ CFU/g, p=0.002). Clinicians reported added value of fluorescence images in >90% of study wounds, including identification of wounds incorrectly diagnosed by CSS (47% of study wounds) and treatment plan modifications guided by fluorescence (73% of study wounds). Modifications included image-guided cleaning, treatment selection, debridement and antimicrobial stewardship.

CONCLUSION

Findings from this pilot study suggest that when used in combination with CSS, bacterial fluorescence may: (1) improve the diagnostic accuracy of identifying patients with wounds containing moderate-to-heavy bacterial loads and (2) guide more timely and appropriate treatment decisions at the point-of-care.

Inflammation Biomarkers and Correlation to Wound Status After Full-Thickness Skin Grafting

Background: A surgical site infection (SSI) is believed to be the result of an exaggerated inflammatory response. Objective: Examine the relationship between clinical status and inflammation biomarkers in full-thickness skin grafting wounds. Methods: Twenty patients planned for facial full-thickness skin grafting were enrolled. A week after surgery, all graft wounds were clinically assessed using a 3-step scale for inflammation (low, moderate, high). All wounds were swabbed for routine microbiological analysis and assessment of numbers of aerobic bacteria. Tie-over dressings from all patients were collected and used for wound fluid extraction and subsequent analysis of MMPs, cytokines, and NF-κB inducing activity. Results: Wounds with a high degree of inflammation contained increased total MMP activity (P ≤ 0.05) in their corresponding fluids. Likewise, the level of the cytokines IL-1ß, IL-8, IL-6, TNF-α was analyzed, and particularly IL-1ß was discriminatory for highly inflamed wounds (P ≤ 0.01). Moreover, bacterial loads were increased in highly inflamed wounds compared to wounds with a low degree of inflammation (P ≤ 0.01). NF-κB activation in the monocytic cell line THP-1 was significantly higher when these cells were stimulated by wound fluids with a high degree of inflammation (P ≤ 0.01). Growth of S. aureus in wounds did not vary between wounds with different degrees of inflammation (chi-square 3.8, P = 0.144). Conclusion: Biomarkers analyzed from tie-over dressings correlated to clinical wound healing in full-thickness skin grafting.

Evaluation of levels of interleukin-6, interleukin-8 and some haematologic parameters of dogs with cutaneous wounds

The aim of the study was to investigate the time-course of serum and wound fluids interleukin (IL)-6 and IL-8 levels in dogs with cutaneous wounds and their relationship with some haematologic parameters. The experimental group comprised of six adult dogs that underwent surgery with wounds (n = 6) on the mid lateral aspect of the right antebrachium; and control group of six, apparently, healthy intact (free from cutaneous wounds) adult dogs, comprising equal number of both sexes. Vital signs evaluated were within normal limits. Samples of blood, serum and wound fluids harvested pre- and at 12 h, 36 h, 60 h, 156 h and 324 h post-injury, were utilised for IL-6 and IL-8 assay and haematology. Peak concentrations of IL-6 in wound fluid (1.33. ± 0.33 ng/mL) and serum (0.82 ± 0.24 ng/mL) of the experimental group at 12 h post-operation were higher (P < 0.01) than the control (0.30 ± 0.05 ng/mL). Concentrations of IL-8 at 12 h and 60 h in wound fluid (0.21 ± 0.05 ng/mL and 0.22 ± 0.11 ng/mL) respectively were lower (P < 0.05) than serum (0.71 ± 0.21 ng/mL and 0.73 ± 0.24 ng/mL) respectively in the experimental group and corresponding values recorded in controls (0.34 ± 0.09 ng/mL and 0.36 ± 0.14 ng/mL). The haematological and biochemical parameters exhibited minimum fluctuations, but values were within normal ranges. Significant correlations were obtained between serum and wound fluid IL-6 (r = 0.827, P < 0.05); wound fluid IL-6 and monocyte count (r = 0.818, P < 0.04); wound fluid IL-6 and haematocrit (r = -0.894, P < 0.05). There was a positive correlation between serum IL-8 and serum IL-6 (r = 0.622, P > 0.05) and serum IL-8 and wound fluid IL-8 (r = 0.718, P > 0.05) in the experimental group. In conclusion, IL-6 and IL-8 exerted modulated inflammatory processes following cutaneous wounds in dogs. Further studies are required to investigate the expression patterns of IL-6 and IL-8 in cutaneous wounds in order to improve the quality of management of cutaneous wounds.

Enhanced healing and anti-inflammatory effects of a carbohydrate polymer with zinc oxide in patients with chronic venous leg ulcers: preliminary results

INTRODUCTION

Insufficient wound healing related to chronic inflammation of chronic venous leg ulcers (CVUs) represents an important public health problem. The aim of this study was to evaluate the effects of a carbohydrate polymer with zinc oxide therapy on CVUs.

MATERIAL AND METHODS

Forty patients with CVUs were recruited for this study and were divided into a study group and control group. Patients In the study group were instructed to use venous compression treatment andtopical carbohydrate polymer with zinc oxide twice daily, while patients In the control group were treated with only venous compression treatment. All patients were followed up for 8 weeks. Peripheral blood samples and biosy tissue specimens were obtained at the initiation of treatment and after 8 weeks to assess serum levels of inflammatory cytokines as well as the percentage of leukocytes, T-helper cells, cytotoxic-T cells, macrophages and endothelial cells in the biopsy tissue using flow cytometry.

RESULTS

A significantly greater reduction in the mean percentage ulcer area from baseline to eight weeks was observed in the study group (up to 40% for large ulcers). Furthermore, the patients in the study group had reduced systemic levels of the pro-inflammatory cytokines IL-8 (p = 0.0028) and IL-6 (p = 0.0302), fewer total CD45+ cells (p = 0.0038) and more CD31+ cells (p = 0.045) present in ulcer biopsies compared to the control group.

CONCLUSIONS

The carbohydrate polymer with zinc oxide treatment with venous compression enhances healing of CVUs and improves quality of life due, in part, to its anti-inflammatory properties.

Levels of wound calprotectin and other inflammatory biomarkers aid in deciding which patients with a diabetic foot ulcer need antibiotic therapy (INDUCE study)

AIMS

Deciding if a diabetic foot ulcer is infected in a community setting is challenging without validated point-of-care tests. Four inflammatory biomarkers were investigated to develop a composite algorithm for mildly infected diabetic foot ulcers: venous white cell count, C-reactive protein (CRP) and procalcitonin, and a novel wound exudate calprotectin assay. Calprotectin is a marker of neutrophilic inflammation.

METHODS

In a prospective study, people with uninfected or mildly infected diabetic foot ulcers who had not received oral antibiotics in the preceding 2 weeks were recruited from community podiatry clinics for measurement of inflammatory biomarkers. Antibiotic prescribing decisions were based on clinicians' baseline assessments and participants were reviewed 1 week later; ulcer infection was defined by clinicians' overall impression from their two assessments.

RESULTS

Some 363 potential participants were screened, of whom 67 were recruited, 29 with mildly infected diabetic foot ulcers and 38 with no infection. One participant withdrew early in each group. Ulcer area was 1.32 cm² [interquartile range (IQR) 0.32-3.61 cm² ] in infected ulcers and 0.22 cm² (IQR 0.09-1.46 cm² ) in uninfected ulcers. Baseline CRP for mild infection was 9.00 mg/ml and 6.00 mg/ml for uninfected ulcers; most procalcitonin levels were undetectable. Median calprotectin level in infected diabetic foot ulcers was 1437 ng/ml and 879 ng/ml in uninfected diabetic foot ulcers. Area under the receiver operating characteristic curve for a composite algorithm incorporating calprotectin, CRP, white cell count and ulcer area was 0.68 (95% confidence intervals 0.52-0.82), sensitivity 0.64, specificity 0.81.

CONCLUSIONS

A composite algorithm including CRP, calprotectin, white cell count and ulcer area may help to distinguish uninfected from mildly infected diabetic foot ulcers. Venous procalcitonin is unhelpful for mild diabetic foot ulcer infection.

Does noncontact low-frequency ultrasound therapy contribute to wound healing at the molecular level?

Noncontact low-frequency ultrasound (NLFU) is used to treat various types of chronic wounds including venous, diabetic, and pressure ulcers. The objective for this substudy of the IN BALANCE RCT VLU trial was to characterize and compare the NLFU treatment group and patients receiving standard of care (SOC) with respect to the effect of the assigned study treatment on content/quantity of inflammatory cytokines and fibrinogen as well as bacteria. Higher mean wound area reduction was observed in the NLFU treatment group (67.0%) compared to the SOC group (41.6%, p < 0.05). Hypertension, diabetes type II, coronary artery disease, and anemia were identified as the most common comorbidities of the Chronic venous leg ulcer (CVLU) patients included in the study. Pseudomonas, Corynebacterium, and unclassified Enterobacteriaceae were dominant in the highest number of samples. Anaerococcus, Peptoniphilus, and Finegoldia, had the highest median proportion in the samples overall. Peptoniphilus abundance decreased more in the NLFU treatment group relative to SOC; similar trends were observed for Anaerococcus and Finegoldia. Progression of mediators like TNF-alpha, IL-1beta, IL-6, IL-8, and IL-10 as well as PF4, TGF-beta, and fibrinogen was monitored and trends for several of the mediators were identified. Fibrinogen amounts were significantly reduced over time in the NLFU treatment group (p < 0.05). IL-8 levels declined in wound fluid from NLFU responders as well as SOC responders. Bacterial load (total bacterial abundance) determined local parameters of ulcer inflammation. If a bioburden of ≥ 10E⁵ was found compared to < 10E⁵ , levels of IL-1beta, IL-8, and TNF-alpha were significantly higher. In conclusion, NLFU treatment is an effective adjuvant tool for CVLU therapy. This study demonstrates that it improves wound healing by equally inhibiting abundant levels of pro-inflammatory cytokines as well as by reducing the overall bacterial burden.

Are there clinical signs and symptoms of infection to indicate the presence of multidrug-resistant bacteria in venous ulcers?

The selection of topical and systemic therapies for the treatment of venous ulcers with signs of infection is challenging and should be accompanied by specific precautionary measures to protect against cross-contamination in the presence of multidrug-resistant microorganisms. However, there are still no clinical indicators for this situation, and confirmation of resistant strains occurs through culture and sensitivity, which can take up to 14 days. During this period, protective measures may no longer be taken, contributing to the spread of these pathogens. This study aimed to analyze the relationship between clinical signs and symptoms of infection in venous ulcers and the presence of antimicrobial-resistant Staphylococcus aureus and/or Pseudomonas spp. A cross-sectional study was developed including 69 patients with 98 venous ulcers. Clinical observation protocol was applied to detect infection indicators established by the European Wound Management Association and microbiological analysis of samples of the lesions. Fisher's exact test and χ² were used for analyses (P < 0.05). Two indicators of infection predominated (f >70%): discoloration of the opaque type and/or dark brick red and increased exudate volume; 31 (31.6%) ulcer samples showed positive culture for the bacteria studied. There was no relationship between signs and symptoms of infection and the presence of multidrug-resistant microorganisms. Taking into account the percentage of lesions with resistant strains, for safe care, contact precautionary measures should be implemented in the treatment rooms, in addition to standard precautions.

Nanoemulsion is an effective antimicrobial for methicillin-resistant Staphylococcus aureus in infected wounds

AIM

To develop NB-201, a nanoemulsion compound, as a novel microbicidal agent against methicillin-resistant Staphylococcus aureus (MRSA) infection, which is a common threat to public health but with limited therapeutic options.

MATERIALS & METHODS

NB-201 was tested in in vitro and in vivo murine and porcine models infected with MRSA.

RESULTS

Topical treatment of MRSA-infected wounds with NB-201 significantly decreased bacterial load and had no toxic effects on healthy skin tissues. NB-201 attenuated neutrophil sequestration in MRSA-infected wounds and inhibited epidermal and deep dermal inflammation. The levels of proinflammatory cytokines were reduced in NB-201-treated MRSA-infected wounds.

CONCLUSION

NB-201 can greatly reduce inflammation characteristic of infected wounds and has antimicrobial activity that effectively kills MRSA regardless of the genetic basis of antibiotic resistance.

Effect of Daptomycin on Local Interleukin-6, Matrix Metalloproteinase-9, and Metallopeptidase Inhibitor 1 in Patients With MRSA-Infected Diabetic Foot

Infection is a major cause of the diabetic foot syndrome that is promoted by the increased burden of multiresistant germs like methicillin-resistant Staphylococcus aureus (MRSA). Maximizing positive outcome for serious MRSA infections requires an aggressive treatment approach and careful monitoring of the healing process. Therefore, we examined 8 patients with MRSA-infected diabetic foot syndrome of Wagner classification grade 2 or 3 (corresponding to the Texas classification stage 2 or 3) during antibiotic treatment with daptomycin. We documented the wound size and obtained samples of wound secretion for analyses of proinflammatory interleukin-6 (IL-6), protease (matrix metalloproteinase-9 [MMP-9]), and antiprotease (metallopeptidase inhibitor 1 [TIMP-1]) activity. During the course of anti-MRSA therapy, we observed a decrease in the concentration of local IL-6 within the first 3 days followed by a decrease of MMP-9 and an increase of TIMP-1. Finally, a reduction of wound size was documented. The present data show that efficient antimicrobial treatment with daptomycin has a number of beneficial effects on wound healing at the molecular level in MRSA-infected diabetic foot ulcers.

Effect of daptomycin on local interleukin-6, matrix metalloproteinase-9, and metallopeptidase inhibitor 1 in patients with MRSA-infected diabetic foot

Infection is a major cause of the diabetic foot syndrome being aggravating by the increased burden of multiresistant germs like methicillin-resistant Staphylococcus aureus (MRSA). Maximizing positive outcome for serious MRSA infections requires an aggressive treatment approach and a careful monitoring of the healing process. Therefore, we examined 8 patients with MRSA-infected diabetic foot syndrome Wagner classification grades 2 or 3 (corresponding to the Texas classification stage 2 and 3) during antibiotic treatment with daptomycin. We documented the wound size and obtained samples of wound secretion for analyses of pro-inflammatory interleukin-6 (IL-6), protease (matrix metalloproteinase-9 [MMP-9]), and antiprotease activity (metallopeptidase inhibitor 1 [TIMP-1]). During the course of anti-MRSA therapy, a decrease in the concentration of local IL-6 within the first 3 days followed by a drop of MMP-9 and an increase of TIMP-1 was observed. Finally, a reduction of wound size could be documented. The present data show that efficient antimicrobial treatment with daptomycin leads to a number of beneficial processes at the molecular level of wound healing in MRSA-infected diabetic foot ulcers.

Wound Fluid in Diabetic Foot Ulceration

Valid and reproducible sampling techniques as well as processing protocols are required for the assessment of biomarkers and mediators contained in wound exudate. Moreover, the ideal technique should be easy to use even in daily clinical routine. This is challenging since wound fluid represents an inhomogeneous mixture of different exogenous and endogenous sources. Analyzing wound fluid, however, may facilitate clinical decision making. Many techniques for obtaining wound fluid have been described. There is very little validation data, and the array of different techniques appears confusing. Structuring and new standards are needed to avoid wound fluid sampling yielding an “undefined soup.” A lot of wound fluid parameters have been analyzed, although none of them have made its way into clinical practice. Nevertheless, basic principles of wound healing have been established from wound fluid analysis. With adequate techniques suitable for daily practice, basic research might foster our clinical understanding of wound healing with implications for new therapies. So far, research has mainly concentrated on analyzing available sample material with respect to either a wide variety of analytes or comparing acute with chronic wound exudate. Clinical endpoints such as healing or wound infection as well as longitudinal data may indeed be more valuable for clinical practice, enabling the discovery of meaningful biomarkers using a suitable technique.

Novel biomarkers for the detection of wound infection by wound fluid RT-PCR in rats

Wound infection is a form of host damage resulting from an imbalance in pathogen virulence and the host immune response. However, at present, diagnosis is based solely on bacterial numbers or inflammatory signs and is therefore not precise. Thus, infection diagnosis requires indicators of both of these factors. We focused on wound fluid because it includes both bacteria and host cells. The purpose of this study was to establish biomarkers that reflect both bacterial and host factors using the reverse transcription-polymerase chain reaction method on the centrifugal precipitation of wound fluids (wound fluid RT-PCR). We created full thickness wounds in animal models of the three groups: control, colonization and infection, which were conditioned by administration of different concentrations of Pseudomonas aeruginosa dispersion. Messenger RNA expression in bacteria and host cells was analysed. Expression of bacterial housekeeping genes was detected in the samples in the colonization and infection groups. Expression of host housekeeping genes was detected in all samples from the three groups. Expression of toxA, encoding the virulence factor exotoxin A, was detected in 90% of samples in the infection group only. Expression of Foxp3, encoding the transcription factor forkhead box P3, was detected in 100% of samples only in the colonization group. These results revealed that wound fluid RT-PCR analysis reflected both bacterial virulence and the host immune status, and we determined the combination of novel biomarkers that can discriminate these three groups. We anticipate that wound fluid RT-PCR could be applied in the future to diagnose wound infection.

[Diabetic foot syndrome]

Diabetic foot ulceration is a serious complication of diabetes mellitus worldwide and the most common cause of hospitalization in diabetic patients. The etiology of diabetic foot ulcerations is complex due to their multifactorial nature. The pathophysiologies of diabetic foot ulceration with polyneuropathy and angiopathy as well as wound-healing impairment in patients with diabetes mellitus are important. Proper adherence to standard treatment strategies and interdisciplinary cooperation can reduce the--compared with European data--noticeably higher rates of major amputations in Germany.

Does inflammation have a role in the pathogenesis of venous ulcers? A critical review of the evidence

Chronic venous disease, a disorder involving venous return from the legs, is a growing epidemic in the developed world. Numerous studies have been conducted in the past two decades in an attempt to elucidate its underlying pathophysiology. Many theories have been proposed to address the profound inflammatory dysregulation, with the majority focusing on fibrin trap, inflammatory trap, cytokines, growth factors, and matrix metalloproteinases. Although many of these theories have obtained great momentum, much of the data are contradictory. Moreover, many treatments built on these theories have claimed overwhelming success despite insufficient evidence. At the same time, there are few reviews that critically analyze and evaluate these data. Therefore, in this paper, we will provide summaries of the background data and evolution of these theories and examine their supporting evidence.

Epidemiology and aetiology of C4-6 disease

Although our understanding of chronic venous insufficiency (CVI) has improved, many important questions remain unanswered. Ensuring that patients are appropriately referred for specialist assessment and then receive evidence-based, cost-effective treatment continues to be challenging. The lifetime of risk of chronic venous ulceration (CVU) is around 1% with approximately 10% ulcers being open at any one time. The incidence skin changes disease is about 10 times greater (10%). However, many of the studies upon which these estimates are based are old and/or methodologically flawed. There is reason to believe that the incidence, prevalence and characteristics of CVI/CVU may have changed considerably over the last 10-20 years and that future change is likely. Further cross-sectional and longitudinal epidemiological studies are required to establish the size and nature of the health-care need going forward in developed and increasingly developing countries. CVI culminating CVU is primarily the result of sustained ambulatory venous hypertension, which in turn arises from superficial and/or deep venous reflux with or without deep vein obstruction. However, there are many other elements to this complex condition, for example, microvascular dysfunction; calf muscle pump efficiency; dermal inflammation; disordered fibroblast function and matrix production; failure of epithelialization; congenital and acquired thrombophilia; malnutrition, obesity and diet; and bacterial colonization. None of the currently available treatment modalities is entirely satisfactory and novel therapies based upon a clearer understanding of the disease at the psychological, genetic, mechanical, microvascular and microscopic level are required.

Investigating the humoral immune response in chronic venous leg ulcer patients colonised with Pseudomonas aeruginosa

The ability to manage the bioburden in chronic wounds is most likely coupled to the humoral immune response of the patient. We analysed markers of systemic immune response in patients with chronic venous leg ulcers (CVLUs) colonised (no-systemic infection) with the opportunistic pathogen Pseudomonas aeruginosa. Sera from 44 clinically non infected patients with CVLUs were analysed for total IgM and IgG isotype 1-4, complement C3, mannose-binding lectin (MBL), interleukin (IL)-6, C-reactive protein (CRP) and specific anti-P. aeruginosa antibodies against exotoxin A, elastase and alkaline phosphatase. Concentrations of IL-6 versus CRP intercorrelated (β = 2.43 95% CI (1.34-4.34)), but were independent of P. aeruginosa colonisation. MBL deficiency (MBL < 500 ng/ml) correlated to high serum levels of IgG(1) (P = 0.038) consistent with a compensatory mechanism, but not related to presence of P. aeruginosa in the ulcers. Twenty-four patients (54.5%) were culture positive for P. aeruginosa, also conferring significantly high serum levels of complement C3 (P = 0.014), but only two of these had positive titres for antibodies against exotoxin A. All patient sera were negative for antibodies against elastase and alkaline phosphatase. Fluorescent in situ hybridization analysis on randomly selected culture-positive patients could not establish unambiguous presence of P. aeruginosa biofilms in the ulcers. A multiple regression model showed P. aeruginosa and systemic CRP as significant factors in deterioration of ulcer healing rate.

Chronic wounds and the medical biofilm paradigm

There is a growing recognition that biofilms are the principal cause of wound chronicity. The development of treatments for wound biofilms raises the prospect that chronic wounds can be treated, potentially saving many patients' lives.