Complicated skin, skin structure and soft tissue infections - are we threatened by multi-resistant pathogens?

Marine-derived polysaccharides and their therapeutic potential in wound healing application - A review

Polysaccharides originating from marine sources have been studied as potential material for use in wound dressings because of their desirable characteristics of biocompatibility, biodegradability, and low toxicity. Marine-derived polysaccharides used as wound dressing, provide several benefits such as promoting wound healing by providing a moist environment that facilitates cell migration and proliferation. They can also act as a barrier against external contaminants and provide a protective layer to prevent further damage to the wound. Research studies have shown that marine-derived polysaccharides can be used to develop different types of wound dressings such as hydrogels, films, and fibres. These dressings can be personalised to meet specific requirements based on the type and severity of the wound. For instance, hydrogels can be used for deep wounds to provide a moist environment, while films can be used for superficial wounds to provide a protective barrier. Additionally, these polysaccharides can be modified to improve their properties, such as enhancing their mechanical strength or increasing their ability to release bioactive molecules that can promote wound healing. Overall, marine-derived polysaccharides show great promise for developing effective and safe wound dressings for various wound types.

Significant increase in the prevalence of Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus, particularly the USA300 variant ΨUSA300, in the Japanese community

IMPORTANCE

USA300 is an MRSA clone producing PVL, a toxin associated with SSTIs. ΨUSA300 is a USA300 variant recently identified in Japan by Takadama et al. (15). Here, we found that the prevalence rate of PVL-positive MRSA in S. aureus was elevated in the Japanese community, and ΨUSA300 accounted for most of them. ΨUSA300 strains have been isolated from several areas in Japan and were associated with deep-seated SSTIs. This study highlighted the emerging threat posed by ΨUSA300 in Japan.

Novel fluorobenzothiazole as a dual inhibitor of gyrase B and topoisomerase IV against Gram-positive pathogens

Aim: The development of a novel inhibitor targeting gyrase B and topoisomerase IV offers an opportunity to combat multidrug resistance. Methods: We investigated the activity of RBx 10080758 against Gram-positive bacteria in vitro and in vivo. Results: RBx 10080758 showed a potent 50% inhibitory concentration of 0.13 μM and 0.25 μM against gyrase B and topoisomerase IV, respectively, and exhibited strong whole-cell in vitro activity with MIC ranges of 0.015-0.06 and 0.015-0.03 μg/ml against Staphylococcus aureus and Streptococcus pneumoniae, respectively. In a rat thigh infection model with methicillin-resistant S. aureus, RBx 10080758 at 45 mg/kg exhibited a >3 log10 CFU reduction in thigh muscles. Conclusion: RBx 10080758 displayed potent activity against multiple multidrug-resistant Gram-positive bacteria with a dual-targeting mechanism of action.

Characterization and mechanism of action of amphibian-derived wound-healing-promoting peptides

Wound-healing-promoting peptides are excellent candidates for developing wound-healing agents due to their small size and low production cost. Amphibians are one of the major sources of bioactive peptides, including wound-healing-promoting peptides. So far, a series of wound-healing-promoting peptides have been characterized from amphibians. We hereby summarized the amphibian-derived wound-healing-promoting peptides and their mechanism of action. Among these peptides, two peptides (tylotoin and TK-CATH) were characterized from salamanders, and twenty five peptides were characterized from frogs. These peptides generally have small sizes with 5-80 amino acid residues, nine peptides (tiger17, cathelicidin-NV, cathelicidin-DM, OM-LV20, brevinin-2Ta, brevinin-2PN, tylotoin, Bv8-AJ, and RL-QN15) have intramolecular disulfide bonds, seven peptides (temporin A, temporin B, esculentin-1a, tiger17, Pse-T2, DMS-PS2, FW-1, and FW-2) are amidated at the C-terminus, and the others are linear peptides without modifications. They all efficiently accelerated the healing of skin wounds or photodamage in mice or rats. They selectively promoted the proliferation and migration of keratinocytes and fibroblasts, recruited neutrophils and macrophages to wounds, and regulated the immune response of neutrophils and macrophages in wounds, which were essential for wound healing. Interestingly, MSI-1, Pse-T2, cathelicidin-DM, brevinin-2Ta, brevinin-2PN, and DMS-PS2 were just antimicrobial peptides, but they also significantly promoted the healing of infected wounds by clearing off bacteria. Considering the small size, high efficiency, and definite mechanism, amphibian-derived wound-healing-promoting peptides might be excellent candidates for developing novel wound-healing-promoting agents in future.

Evaluation of the Risk Factors for Cellulitis among Patients with Peripheral Artery Disease

Background and objectives: The objective of this study is to elucidate peripheral occlusion artery disease (PAOD) as a risk factor for cellulitis. Materials and Methods: This is a retrospective population-based cohort study. The database is the Longitudinal Health Insurance Database, which covers two million beneficiaries from the entire population of the 2010 registry for beneficiaries in Taiwan. The PAOD group is composed of patients who were newly diagnosed with PAOD from 2001 to 2014. The non-PAOD group is composed of patients who were never diagnosed with PAOD from 2001 to 2015. All patients were followed until the onset of cellulitis, death, or until the end of 2015. Results: Finally, 29,830 patients who were newly diagnosed with PAOD were included in the PAOD group, and 29,830 patients who were never diagnosed with PAOD were included in the non-PAOD group. The incidence densities (ID) of cellulitis were 26.05 (95% CI = 25.31-26.80) patients per 1000 person-years in the PAOD group and 49.10 (95% CI = 48.04-50.19) in the non-PAOD group. The PAOD group had an increased risk of cellulitis (adjusted HR = 1.94, 95% CI = 1.87-2.01) compared to the non-PAOD group. Conclusions: Patients with PAOD were associated with a higher risk of subsequent cellulitis compared to patients without PAOD.

Diabetes and skin cancers: Risk factors, molecular mechanisms and impact on prognosis

Diabetes and skin cancers have emerged as threats to public health worldwide. However, their association has been less intensively studied. In this narrative review, we explore the common risk factors, molecular mechanisms, and prognosis of the association between cutaneous malignancies and diabetes. Hyperglycemia, oxidative stress, low-grade chronic inflammation, genetic, lifestyle, and environmental factors partially explain the crosstalk between skin cancers and this metabolic disorder. In addition, diabetes and its related complications may interfere with the appropriate management of cutaneous malignancies. Antidiabetic medication seems to exert an antineoplastic effect, however, future large, observation studies with a prospective design are needed to clarify its impact on the risk of malignancy in diabetes. Screening for diabetes in skin cancers, as well as close follow-up for the development of cutaneous malignancies in subjects suffering from diabetes, is warranted.

Photo-Activated Nanofibrous Membrane with Self-Rechargeable Antibacterial Function for Stubborn Infected Cutaneous Regeneration

For quick disinfection treatment, phototherapy, including photothermal therapy and photodynamic therapy, has emerged as a promising alternative to conventional methods. However, the bactericidal effect of phototherapy, which only works upon light, is short-lived. The remaining bacteria in situ may repopulate when the irradiation of light is withdrawn. To address this refractory concern, an antibacterial fibrous membrane consisting of electrospun poly (polycaprolactone) scaffolds and polydopamine (pDA) coated MXene/Ag₃ PO₄ bioheterojunctions (MX@AgP bio-HJs) is devised and developed. Upon near-infrared (NIR) illumination, the MX@AgP nanoparticle (NP) in nanofibrous electrospun membranes exert the excellent bactericidal effect of phototherapy and release Ag⁺ ions which stop the remaining bacteria from multiplying in the dark state. When removing NIR light, pDA in situ reduces Ag⁺ ions to Ag⁰ NPs to realize the self-rechargeability of Ag⁺ ions and provides enough Ag⁺ ions for the second phototherapy. In vivo results show that photoactivated nanofibrous membranes can re-shape an infected wound microenvironment to the regenerative microenvironment through killing bacteria, ceasing bleeding, increasing epithelialization, and collagen deposition on the wound bed, as well as promoting angiogenesis. As predicted, the proposal work offers potential prospects for nanofibrous membranes with NIR-assisted "self-rechargeable" antibacterial properties to treat bacteria-infected full-thickness wounds.

Multidrug-resistant Bacterial Profile and Patterns for Wound Infections in Nongovernmental Hospitals of Jordan

Globally, multidrug-resistant bacteria affects wound infections, both hospital-acquired infections and community-acquired infections. The main isolates cultured from 607 subjects with wound infections were methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter spp. [multidrug resistant (MDR)]. Gram-negative bacteria caused most of the infections (67%) compared with gram-positive bacteria. Diabetic patients tend to have wound infections with mixed causative agents compared with non-diabetic patients.

[Treatment strategies and outcomes for injection-associated inguinal perivascular abscesses in intravenous drug addicts]

Hintergrund

Langzeitdrogenabhängige präsentieren sich nach dem Verbrauch der oberflächlichen Venen regelmäßig mit tiefen inguinalen vaskulär assoziierten Abszessen infolge fortgesetzter Drogeninjektionen. Die Behandlung dieser Komplikationen stellt anhaltend eine große medizinische Herausforderung dar. Bisher werden keine einheitlichen Therapieregime in der Literatur beschrieben.

Fragestellung

Welche Behandlungsstrategien und Ergebnisse gibt es bei injektionsassoziierten inguinalen perivaskulären Abszessen bei Drogenabhängigen?

Material und Methoden

Die Daten aller im Zeitraum zwischen 01.01.2004 und 31.05.2019 am Universitätsklinikum Augsburg behandelten Drogenkonsumenten wurden retrospektiv aufgearbeitet und mit der vorliegenden Literatur verglichen.

Ergebnisse

Es konnten 37 Fälle (männlich = 25, weiblich = 12) nach Anwendung der Einschlusskriterien in die Datenerhebung eingeschlossen werden. Das mediane Alter im untersuchten Patientenkollektiv lag bei 34,3 Jahren. Die 30-Tage-Mortalität lag bei 2,7 % (1/37). Die Amputationsrate betrug 2,8 %. Im untersuchten Kollektiv lag bei 13 Patienten eine arterielle Beteiligung vor. In 5 Fällen wurde primär arteriell ligiert. Bei weiteren 5 Fällen wurde primär eine Rekonstruktion mittels autologen Interponats durchgeführt. In weiteren 3 Fällen erfolgte die Anlage eines Obturatorbypasses (1/3) sowie die Durchführung einer Patchplastik (2/3). Die Offenheitsrate nach arterieller Rekonstruktion lag bei 87,5 % bei einem mittleren Follow-up von 421 Tagen. Die Gesamtkomplikationsrate lag bei 51,4 %.

Diskussion

Bei vaskulärer Beteiligung ist ein situationsgerechtes Vorgehen sinnvoll. Neben der Beseitigung komplizierter, septisch-venöser Thrombosen erscheint die Korrektur arterieller Blutungen mittels autologer Rekonstruktionsmaßnahmen aussichtsreich.

Topical antimicrobial peptide formulations for wound healing: Current developments and future prospects

Antimicrobial peptides (AMPs) are the natural antibiotics recognized for their potent antibacterial and wound healing properties. Bare AMPs have limited activity following topical application attributable to their susceptibility to environment (hydrolysis, oxidation, photolysis), and wound (alkaline pH, proteolysis) related factors as well as minimal residence time. Therefore, the formulation of AMPs is essential to enhance stability, prolong delivery, and optimize effectiveness at the wound site. Different topical formulations of AMPs have been developed so far including nanoparticles, hydrogels, creams, ointments, and wafers to aid in controlling bacterial infection and enhance wound healing process in vivo. Herein, an overview is provided of the AMPs and current understanding of their formulations for topical wound healing applications along with suitable examples. Furthermore, future prospects for the development of effective combination AMP formulations are discussed. STATEMENT OF SIGNIFICANCE: Chronic wound infection and subsequent development of antibiotic resistance are serious clinical problems affecting millions of people worldwide. Antimicrobial peptides (AMPs) possess great potential in effectively killing the bacteria with minimal risk of resistance development. However, AMPs susceptibility to degradation following topical application limits their antimicrobial and wound healing effects. Therefore, development of an optimized topical formulation with high peptide stability and sustained AMP delivery is necessary to maximize the antimicrobial and wound healing effects. The present review provides an overview of the state-of-art in the field of topical AMP formulations for wound healing. Current developments in the field of topical AMP formulations are reviewed and future prospects for the development of effective combination AMP formulations are discussed.

Reducing injection intensity is associated with decreased risk for invasive bacterial infection among high-frequency injection drug users

Background

Bacterial infection is a major cause of morbidity and mortality for persons who inject drugs (PWID). Injection cessation may help abrogate such infections, but maintaining complete cessation is challenging. Limited data exists on the role of reduced injection intensity on invasive bacterial infection risk. We sought to evaluate decreased risk for bacterial infections following cessation and substantive reduction in the injection intensity.

Methods

Participants were persons in the AIDS Linked to the Intravenous Experience (ALIVE) cohort with initial high-frequency injection drug use (> 1 daily). Pooled logistic regression with generalized estimating equations was used to estimate risk for invasive bacterial infection (pneumonia, endocarditis, or sepsis) among participants achieving complete injection cessation or reduced injection intensity relative to those with sustained high-frequency use.

Results

Of 2247 study participants with 12,469 paired study visits, complete injection cessation was achieved at 13.5% and reduced injection intensity at 25.5% of study visits. Adjusting for sociodemographics and HIV status, injection cessation was associated with a 54% reduction of bacterial infection at 3 months (odds ratio [OR] 0.46, 95% CI 0.25–0.84) and a 46% reduction at 6 months (OR 0.54, 95% CI 0.36–0.81). Reduced injection intensity was associated with a 36% reduction of infection at 3 months (OR 0.64, 95% CI 0.43–0.96) and a 26% reduction at 6 months (OR 0.74, 95% CI 0.56–0.98).

Conclusions

Both complete cessation and reduced injection frequency demonstrate substantial benefit in reducing invasive bacterial infection risk among PWID. With high rates of relapse into injection use, targeting sustained reductions in drug use intensity may be a key harm reduction modality for improving clinical outcomes in this population.

Electronic supplementary material

The online version of this article (10.1186/s12954-019-0312-8) contains supplementary material, which is available to authorized users.

Skin Complications of Orthopedic Procedures and Devices

BACKGROUND

Knowledge of skin complications and contributing factors in orthopedic patients is important for design and development of preventive approaches. Therefore, this study was designed to assess skin complications in orthopedic patients.

METHODS

In this case-series study, 126 orthopedic patients referred to Rasoul-e-Akram and Bahman hospitals from 2012 to 2016 with skin complications were analyzed. The adverse effects were assessed with respect to type and contributing factors. Fisher's exact test, Chi-square, and independent sample t-test were performed to assess the associations between skin complications and other variables.

RESULTS

Skin complications in orthopedic patients included infections in 33 (26.1%) cases and hypersensitivity reactions in 88 (40%) cases. In total, 66 (55%) cases of fracture and 35 (29.2%) cases of cellulitis were detected, while the remaining cases involved complications such as disc herniation, nerve involvement, and osteoarthritis-related arthroplasty. Severe reactions presenting as toxic epidermal necrolysis were observed in 3 patients, 2 of whom died eventually. Age and gender were not related to the type of skin complications (P>0.05).

CONCLUSION

Complications due to orthopedic treatments were not common. However, since the disease may become fatal on certain occasions, patients should receive more attention from physicians and nurses.

Management of complicated skin and soft tissue infections with a special focus on the role of newer antibiotics

Complicated skin and soft tissue infections (cSSTIs) represent the severe form of infectious disease that involves deeper soft tissues. Involvement of methicillin-resistant Staphylococcus aureus (MRSA) further complicates cSSTI with increased hospitalization, health care costs, and overall mortality. Various international guidelines provide recommendations on the management of cSSTIs, with the inclusion of newer antibiotics. This literature-based review discusses the overall management of cSSTI, including appropriate use of antibiotics in clinical practice. Successful treatment of cSSTIs starts with early and precise diagnosis, including identification of causative pathogen and its load, determination of infection severity, associated complications, and risk factors. The current standard-of-care for cSSTIs involves incision, drainage, surgical debridement, broad-spectrum antibiotic therapy, and supportive care. In recent years, the emergence of newer antibiotics (eg, ceftaroline, tigecycline, daptomycin, linezolid, etc) has provided clinicians wider options of antimicrobial therapy. Selection of antibiotics should be based on the drug characteristics, effectiveness, safety, and treatment costs, alongside other aspects such as host factors and local multidrug resistance rates. However, larger studies on newer antibiotics are warranted to refine the decision making on the appropriate antimicrobial therapy. Local Antimicrobial Stewardship Program strategies in health care settings could guide clinicians for early initiation of specific treatments to combat region-specific antimicrobial resistance, minimize adverse effects, and to improve outcomes such as reduction in Clostridium difficile infections. These strategies involving iv-to-oral switch, de-escalation to narrow-spectrum antibiotics, and dose optimization have an impact on the overall improvement of cSSTI therapy outcomes, especially in countries like Singapore that has a high disease burden.

Skin and Soft Tissue Infections in the Emergency Department

This article covers the diagnosis and treatment of skin and soft tissue infections commonly encountered in the emergency department: impetigo, cutaneous abscesses, purulent cellulitis, nonpurulent cellulitis, and necrotizing skin and soft tissue infections. Most purulent infections in the United States are caused by methicillin-resistant Staphylococcus aureus. For abscesses, we emphasize the importance of incision and drainage. Nonpurulent infections are usually caused by streptococcal species and initial empiric antibiotics need not cover methicillin-resistant Staphylococcus aureus. For uncommon but potentially lethal necrotizing skin and soft tissue infections, the challenge is rapid diagnosis in the emergency department and prompt surgical exploration and debridement.

A Novel In Vitro Wound Healing Assay to Evaluate Cell Migration

The aim of this work is to show a novel method to evaluate the ability of some immunomodulatory molecules, such as antimicrobial peptides (AMPs), to stimulate cell migration. Importantly, cell migration is a rate-limiting event during the wound-healing process to re-establish the integrity and normal function of tissue layers after injury. The advantage of this method over the classical assay, which is based on a manually made scratch in a cell monolayer, is the usage of special silicone culture inserts providing two compartments to create a cell-free pseudo-wound field with a well-defined width (500 μm). In addition, due to an automated image analysis platform, it is possible to rapidly obtain quantitative data on the speed of wound closure and cell migration. More precisely, the effect of two frog-skin AMPs on the migration of bronchial epithelial cells will be shown. Furthermore, pretreatment of these cells with specific inhibitors will provide information on the molecular mechanisms underlying such events.

Cross-Linked Polymer-Stabilized Nanocomposites for the Treatment of Bacterial Biofilms

Infections caused by bacterial biofilms are an emerging threat to human health. Conventional antibiotic therapies are ineffective against biofilms due to poor penetration of the extracellular polymeric substance secreted by colonized bacteria coupled with the rapidly growing number of antibiotic-resistant strains. Essential oils are promising natural antimicrobial agents; however, poor solubility in biological conditions limits their applications against bacteria in both dispersed (planktonic) and biofilm settings. We report here an oil-in-water cross-linked polymeric nanocomposite (∼250 nm) incorporating carvacrol oil that penetrates and eradicates multidrug-resistant (MDR) biofilms. The therapeutic potential of these materials against challenging wound biofilm infections was demonstrated through specific killing of bacteria in a mammalian cell-biofilm coculture wound model.

Emergency Hybrid Approach to Ruptured Femoral Pseudoaneurysm in HIV-positive Intravenous Drug Abusers

BACKGROUND

Chronic traumatism of the common femoral artery due to intravenous injection in drug abusers, in association with local infections and arterial wall weakening caused by human immunodeficiency virus (HIV), can lead to the development of pseudoaneurysms (PSAs). Rupture of PSA is a dramatic event in such patients, and its correction is difficult and controversial. Most of the cases reported describe open surgical elective options, which consist in ligation, repair, or substitution of the damaged arterial segment, using when possible biological grafts. In literature, few cases describe an endovascular repair with covered stent deployment.

METHODS

We present 2 cases of HIV-positive intravenous injection in drug abusers who needed emergency treatment for active bleeding in ruptured PSA of the right common femoral artery. In both cases, under general anesthesia needed for lack of patient's compliance and unstable hemodynamics, a short dissection to the distal superficial femoral artery was required.

RESULTS

Then, maintaining a manual compression on the bleeding site to stop hemorrhage, we deployed a covered stent graft in the site of the arterial breakdown through a retrograde approach.

CONCLUSIONS

The favorable results and progressive healing of wound and local infections persuaded us not to perform any further surgical correction. The absence of recurrences and late complications, after 3 years in the first case and 1 year in the second one, lead us to consider this hybrid endovascular approach as a valuable alternative to open surgery in HIV intravenous injection in drug abuser patients, in particularly when emergency conditions occur.

Antimicrobial peptides and wound healing: biological and therapeutic considerations

Repair of tissue wounds is a fundamental process to re-establish tissue integrity and regular function. Importantly, infection is a major factor that hinders wound healing. Multicellular organisms have evolved an arsenal of host-defense molecules, including antimicrobial peptides (AMPs), aimed at controlling microbial proliferation and at modulating the host's immune response to a variety of biological or physical insults. In this brief review, we provide the evidence for a role of AMPs as endogenous mediators of wound healing and their promising therapeutic potential for the treatment of non-life-threatening skin and other epithelial injuries.

World Society of Emergency Surgery (WSES) guidelines for management of skin and soft tissue infections

Skin and soft tissue infections (SSTIs) encompass a variety of pathological conditions ranging from simple superficial infections to severe necrotizing soft tissue infections. Necrotizing soft tissue infections (NSTIs) are potentially life-threatening infections of any layer of the soft tissue compartment associated with widespread necrosis and systemic toxicity. Successful management of NSTIs involves prompt recognition, timely surgical debridement or drainage, resuscitation and appropriate antibiotic therapy. A worldwide international panel of experts developed evidence-based guidelines for management of soft tissue infections. The multifaceted nature of these infections has led to a collaboration among surgeons, intensive care and infectious diseases specialists, who have shared these guidelines, implementing clinical practice recommendations.

Clinical efficacy of tigecycline used as monotherapy or in combination regimens for complicated infections with documented involvement of multiresistant bacteria

INTRODUCTION

Tigecycline is an established treatment option for infections with multiresistant bacteria (MRB). It retains activity against many strains with limited susceptibility to other antibiotics. Efficacy and safety of tigecycline as monotherapy or in combination regimens were investigated in a prospective noninterventional study involving 1,025 severely ill patients in clinical routine at 137 German hospitals.

MATERIALS AND METHODS

Data on the full population have been published; our present analysis focuses on infections caused by MRB. The study population included patients with complicated infections, high disease severity (APACHE II > 15: 65 %) and high MRB prevalence. Most patients had comorbidities, including cardiovascular disease, renal insufficiency, and/or diabetes mellitus. Treatment success was defined as cure/improvement without requirement of further antibiotic therapy.

RESULTS

Pathogens isolated from 215 evaluable patients with documented MRB infections included 132 methicillin-resistant Staphylococcus aureus (MRSA), 42 vancomycin-resistant Enterococci (VRE) and 67 Gram-negative extended beta-lactamase (ESBL) producers. Of the MRB subpopulation, 140 patients received tigecycline monotherapy, 75 were treated with combination regimens. High overall clinical success rates were recorded for MRB infections treated with tigecycline alone (94 %) or in combinations (88 %); in detail intraabdominal infections (monotherapy: 90 %; combinations: 93 %), skin/soft tissue infections (93; 100 %), community-acquired pneumonia (100; 100 %), hospital-acquired pneumonia (94,7; 72,7 %), diabetic foot infections (89; 33 %), blood stream infections (100; 100 %) and multiple-site infections (92; 71 %).

CONCLUSIONS

Tigecycline achieved high clinical success rates in patients with documented infections involving MRB strains despite high disease severity. These results add to the evidence indicating that tigecycline is a valuable therapeutic option for complicated infections in severely ill patients with a high likelihood of multidrug-resistant pathogen involvement.

Prevalence and factors associated with wound colonization by Staphylococcus spp. and Staphylococcus aureus in hospitalized patients in inland northeastern Brazil: a cross-sectional study

Background

Infections by Staphylococcus spp. are often associated with wounds, especially in hospitalized patients. Wounds may be the source of bacteria causing cross-contamination, and are a risk factor for methicillin-resistant Staphylococcus aureus (MRSA) infection. The aim of this study was to investigate the prevalence of wound colonization by Staphylococcus spp., especially S. aureus and MRSA, in hospitalized patients, and to identify the factors associated with such colonization.

Methods

This cross-sectional study enrolled patients with wounds who were hospitalized in a remote and underdeveloped inland region of northeastern Brazil with extreme poverty. Samples were collected using sterile swabs with 0.85% saline solution, and coagulase-negative Staphylococcus spp., S. aureus, and MRSA were identified using standard laboratory procedures. Data regarding the sociodemographic characteristics, antibiotic use, and comorbidities of the patients were collected using the medical records and a questionnaire.

Results

A total of 125 wounds were analyzed. The patients had a mean age of 63.88 years and a mean 3.84 years of school education. Eighty-one wounds (64.80%) were colonized by Staphylococcus spp. Twenty-five wounds (20%) were colonized by S. aureus, 32% of which were colonized by MRSA. Wound colonization by Staphylococcus spp. was associated with pneumonia or other respiratory disease (p = 0.03). Wound colonization by S. aureus was associated with nasal colonization by S. aureus (p < 0.001), fewer days of prior antibiotic use (p = 0.04), admission to a medical ward (p = 0.02), and age >65 years (p = 0.05). Among patients with wound colonization by MRSA, 37.50% had a history of prior antibiotic use, 75% had two or more comorbidities, 25% had cancer or diabetes, 50% had cardiovascular disease, and 50% died.

Conclusions

Wounds can be the source of Staphylococcus spp. infection, and high proportions of wounds are colonized by S. aureus and MRSA. Nasal colonization by S. aureus may be a source for wound colonization by S. aureus, illustrating the importance of preventing cross-contamination in hospital environments, especially among elderly patients. Wounds should be carefully managed to prevent microbial spread, thereby assisting patient recovery and reducing healthcare costs.

Management of EGFR-inhibitor associated rash: a retrospective study in 49 patients

BACKGROUND

In recent years inhibitors directed against the epidermal growth factor receptor (EGFR) have evolved as effective targeting cancer drugs. Characteristic papulopustular exanthemas, often described as acneiform rashes, are the most frequent adverse effect associated with this class of novel cancer drugs and develop in > 90% of patients. Notably, the rash may significantly compromise the patients' quality of life, thereby potentially leading to incompliance as well as dose reduction or even termination of the anti-EGFR therapy. Yet, an effective dermatologic management of cutaneous adverse effects can be achieved. Whereas various case reports, case series or expert opinions on the management of EGFR-inhibitor (EGFRI) induced rashes have been published, data on systematic management studies are sparse.

METHODS

Here, we present a retrospective, uncontrolled, comparative study in 49 patients on three established regimens for the management of EGFRI-associated rashes.

RESULTS

Strikingly, patients' rash severity improved significantly over three weeks of treatment with topical mometason furoate cream, topical prednicarbate cream plus nadifloxacin cream, as well as topical prednicarbate cream plus nadifloxacin cream plus systemic isotretinoin.

CONCLUSIONS

In summary our results demonstrate that EGFRI-associated rashes can be effectively managed by specific dermatologic interventions. Whereas mild to moderate rashes should be treated with basic measures in combination with topical glucocorticosteroids or combined regiments using glucocorticosteroids and antiseptics/antibiotics, more severe or therapy-resistant rashes are likely to respond with the addition of systemic retinoids.

The antimicrobial efficacy of silver on antibiotic-resistant bacteria isolated from burn wounds

The antibiotic-resistant bacteria are a major concern to wound care because of their ability to resist many of the antibiotics used today to treat infections. Consequently, other antimicrobials, in particular ionic silver, are considered ideal topical agents for effectively helping to manage and prevent local infections. Little is known about the antimicrobial efficacy of ionic silver on antibiotic-resistant bacteria at different pH values. Consequently, in this study our aim was to evaluate the effect of pH on the antimicrobial efficacy of a silver alginate (SA) and a silver carboxymethyl cellulose (SCMC) dressing on antibiotic-resistant bacteria isolated from burn patients. Forty-nine antibiotic-resistant bacteria, including Vancomycin-resistant Enterococcus faecium, meticillin-resistant Staphylococcus aureus, multidrug-resistant (MDR) Pseudomonas aeruginosa, MDR Vibrio sp, MDR Stenotrophomonas maltophilia, extended-spectrum ß-lactamase (ESBL) producing Salmonella sp, ESBL producing Klebsiella pneumoniae, ESBL producing Proteus mirabilis, ESBL producing Escherichia coli and MDR Acinetobacter baumannii, routinely isolated from burn wounds were used in the study and evaluated for their susceptibility to two silver containing wound dressings using a standardised antimicrobial efficacy screening assay [corrected zone of inhibition (CZOI)]. The mean overall CZOI for the Gram-positive isolates at a pH of 5·5 were very similar for both dressings. A mean CZOI of 5 mm was recorded for the SCMC dressing, which was slightly higher, at 5·4 mm for the SA dressing. At a pH of 7·0 both dressings, in general, showed a similar activity. However, at a pH of 8·5 the mean CZOI of the SCMC dressing was found to be significantly (P < 0·05) higher than the SA dressing for a select number of isolates. The mean overall CZOI for the Gram-negative bacteria followed a similar pattern as observed with the Gram-positive bacteria. Susceptibility to silver ions did vary significantly between genera and species of bacteria. Interestingly, when pH was changed from 8·5 to 5·5 antimicrobial activity for both dressings in general increased significantly (P < 0·05). Overall, all forty-nine antibiotic-resistant bacteria isolated from burn wounds showed susceptibility to the antimicrobial activity of both silver containing wound dressings over all pH ranges. In addition, the study showed that the performance of both dressings apparently increased when pH became more acidic. The findings in this study may help to further enhance our knowledge of the role pH plays in affecting both bacterial susceptibility and antimicrobial activity of silver containing wound dressings.

In vitro antimicrobial studies of silver carbene complexes: activity of free and nanoparticle carbene formulations against clinical isolates of pathogenic bacteria

OBJECTIVES

Silver carbenes may represent novel, broad-spectrum antimicrobial agents that have low toxicity while providing varying chemistry for targeted applications. Here, the bactericidal activity of four silver carbene complexes (SCCs) with different formulations, including nanoparticles (NPs) and micelles, was tested against a panel of clinical strains of bacteria and fungi that are the causative agents of many skin and soft tissue, respiratory, wound, blood, and nosocomial infections.

METHODS

MIC, MBC and multidose experiments were conducted against a broad range of bacteria and fungi. Time-release and cytotoxicity studies of the compounds were also carried out. Free SCCs and SCC NPs were tested against a panel of medically important pathogens, including methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant Acinetobacter baumannii (MRAB), Pseudomonas aeruginosa, Burkholderia cepacia and Klebsiella pneumoniae.

RESULTS

All four SCCs demonstrated strong efficacy in concentration ranges of 0.5-90 mg/L. Clinical bacterial isolates with high inherent resistance to purified compounds were more effectively treated either with an NP formulation of these compounds or by repeated dosing. Overall, the compounds were active against highly resistant bacterial strains, such as MRSA and MRAB, and were active against the biodefence pathogens Bacillus anthracis and Yersinia pestis. All of the medically important bacterial strains tested play a role in many different infectious diseases.

CONCLUSIONS

The four SCCs described here, including their development as NP therapies, show great promise for treating a wide variety of bacterial and fungal pathogens that are not easily killed by routine antimicrobial agents.