Treatments for skin and soft-tissue and surgical site infections due to MDR Gram-positive bacteria

Emergency department care of ABSSSI with dalbavancin infusion, direct discharge, and outpatient telemedicine follow up: a study protocol

Novel therapeutic strategies such as the long-acting lipoglycopeptide antibiotics allow for the treatment and discharge of selected emergency department (ED) patients with Acute Bacterial Skin and Skin Structure Infections (ABSSSI), who require intravenous antibiotics and would otherwise be hospitalized. The COVID-19 pandemic highlighted the need to develop strategies that may reduce hospitalization. The telehealth approach has shown success in remote management of cellulitis patients and could aid in the remote follow up of overall ABSSSI patients. This article describes a study protocol for the telemedicine follow up of patients diagnosed with ABSSSI in the ED, requiring intravenous treatment, receiving a single dalbavancin dose, and directly discharged. A telehealth system for remote follow up is evaluated as well as the possible inclusion of point-of-care ultrasound for the appropriate diagnosis of ABSSSI. The study will be conducted in compliance with regulatory requirements; and all collected data will be kept strictly confidential and in accordance with all relevant legislation on the control and protection of personal information. Dissemination of the study protocol may help increasing knowledge and awareness on this topic, with the aim of optimizing patient management, reducing hospitalization and lower the impact on healthcare associated costs.

Community-Acquired Skin and Soft Tissue Infections: Epidemiology and Management in Patients Presenting to the Emergency Department of a Tertiary Care Hospital

BACKGROUND

Skin and soft tissue infections are one of the most common diseases presenting to the emergency department (ED). There is no study available on the management of Community-Acquired Skin and Soft Tissue Infections (CA-SSTIs) in our population recently. This study aims to describe the frequency and distribution of CA-SSTIs as well as their medical and surgical management among patients presenting to our ED.

METHODS

We conducted a descriptive cross-sectional study on patients presenting with CA-SSTIs to the ED of a tertiary care hospital in Peshawar, Pakistan. The primary objective was to estimate the frequency of common CA-SSTIs presenting to the ED and to assess the management of these infections in terms of diagnostic workup and treatment modalities used. The secondary objectives were to study the association of different baseline variables, diagnostic modalities, treatment modalities, and improvement with the surgical procedure performance for these infections. Descriptive statistics were obtained for quantitative variables like age. Frequencies and percentages were derived for categorical variables. The chi-square test was used to compare different CA-SSTIs in terms of categorical variables like diagnostic and treatment modalities. We divided the data into two groups based on the surgical procedure. A chi-square analysis was conducted to compare these two groups in terms of categorical variables.

RESULTS

Out of the 241 patients, 51.9% were males and the mean age was 34.2 years. The most common CA-SSTIs were abscesses, infected ulcers, and cellulitis. Antibiotics were prescribed to 84.2% of patients. Amoxicillin + Clavulanate was the most frequently prescribed antibiotic. Out of the total, 128 (53.11%) patients received some type of surgical intervention. Surgical procedures were significantly associated with diabetes mellitus, heart disease, limitation of mobility, or recent antibiotic use. There was a significantly higher rate of prescription of any antibiotic and anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) agents in the surgical procedure group. This group also saw a higher rate of oral antibiotics prescription, hospitalization, wound culture, and complete blood count.

CONCLUSION

This study shows a higher frequency of purulent infections in our ED. Antibiotics were prescribed more frequently for all infections. Surgical procedures like incision and drainage were much lower even in purulent infections. Furthermore, beta-lactam antibiotics like Amoxicillin-Clavulanate were commonly prescribed. Linezolid was the only systemic anti-MRSA agent prescribed. We suggest physicians should prescribe antibiotics appropriate to the local antibiograms and the latest guidelines.

New Clinical Applications of Electrolyzed Water: A Review

As the situation of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is still deteriorating, there has been a huge increase in the demand and use of disinfectants. Electrolyzed water (EW), as a novel broad-spectrum disinfectant and cleaner, has been widely used for several years. EW can be produced in an electrolysis chamber which contains dilute salt and tap water. It is an effective antimicrobial and antibiofilm agent, with several advantages such as on-the-spot, cheap, environmentally friendly and safe for human beings. Therefore, EW holds potential significance for high-risk settings in hospitals and other clinical facilities. EW can also be applied for wound healing, advanced tissue care, and dental clinics. The present review article highlights the latest developments and new perspectives of EW, especially in clinical fields. Furthermore, the main action modes of antibiofilm and antimicrobial will be summarized.

Economic and organizational sustainability of a negative-pressure portable device for the prevention of surgical-site complications

Purpose

Surgical-site complications (SSCs) affect patients’ clinical pathway, prolonging their hospitalization and incrementing their management costs. The present study aimed to assess the economic and organizational implications of a portable device for negative-pressure wound therapy (NPWT) implementation, compared with the administration of pharmacological therapies alone for preventing surgical complications in patients undergoing general, cardiac, obstetrical–gynecological, or orthopedic surgical procedures.

Patients and methods

A total of 8,566 hospital procedures, related to the year 2015 from one hospital, were evaluated considering infection risk index, occurrence rates of SSCs, drug therapies, and surgical, diagnostic, and specialist procedures and hematological exams. Activity-based costing and budget impact analyses were implemented for the economic assessment.

Results

Patients developing an SSC absorbed i) 64.27% more economic resources considering the length of stay (€ 8,269±2,096 versus € 5,034±2,901, p<0.05) and ii) 42.43% more economic resources related to hematological and diagnostic procedures (€ 639±117 versus € 449±72, p<0.05). If the innovative device had been used over the 12-month time period, it would have decreased the risk of developing SSCs; the hospital would have realized an average reduction in health care expenditure equal to −0.69% (−€ 483,787.92) and an organizational saving in terms of length of stay equal to −1.10% (−898 days), thus allowing 95 additional procedures.

Conclusion

The implementation of a portable device for NPWT would represent an effective and sustainable strategy for reducing the management costs of patients. Economic and organizational savings could be reinvested, thus i) treating a wider population and ii) reducing waiting lists, with a higher effectiveness in terms of a decrease in complications.

Clinical characteristics of patients with lower limb cellulitis and antibiotic usage in Hospital Kuala Lumpur: a 7-year retrospective study

BACKGROUND

Cellulitis commonly involved lower limbs. This study was carried out to determine the demography, clinical characteristics, risk factors, microbiological aspects, and antibiotics usage in this group of patients in Hospital Kuala Lumpur.

METHODS

A total of one hundred and twenty four patients with lower limb cellulitis treated in the Department of Dermatology, Hospital Kuala Lumpur, between January 2008 and May 2013 were included in this study.

RESULTS

There were 70 male and 54 female patients, aged between 13 and 87 years (mean 57.23±12.854). Thirty-one of them (25%) had recurrent cellulitis. Fifty-seven (46%) had fever at presentation, 55 (44.4%) had bullous cellulitis. The top risk factors identified were toe web intertrigo (n = 79, 63.7%), hypertension (n=76, 61.3%), obesity (n = 55, 44.4%), and diabetes (n = 55, 44.4%). However, only toe web intertrigo (p = 0.003), peripheral vascular disease (p = 0.01), and varicose veins (p = 0.02) were significantly higher in recurrent cellulitis. Thirty patients (24.2%) were complicated with lipodermatosclerosis, and six (4.8%) had lymphostasis verrucosa cutis. Skin swab cultures were positive in 54 (43.5%) patients, and Pseudomonas sp. was the most frequently identified organism. Mean number of antibiotics given for one episode of cellulitis was 1.7±1. The antibiotics most given were cloxacillin (n=57, 46%) and other penicillins (n = 71, 57%), followed by cephalosporins (n = 40, 32%).

CONCLUSION

Identifying clinical characteristics of those at risk may help to prevent recurrence of cellulitis and long-term complications.

IB-367 pre-treatment improves the in vivo efficacy of teicoplanin and daptomycin in an animal model of wounds infected with meticillin-resistant Staphylococcus aureus

Antimicrobial peptides are known as immunomodulators and antibiotic enhancers. We report that administration of an antimicrobial peptide, IB-367, was efficacious in increasing the antimicrobial activity of daptomycin and teicoplanin in a mouse model of wound infection caused by meticillin-resistant Staphylococcus aureus (MRSA). Mice were assigned to seven groups: an IB-367 pre-treated group with no antibiotics given after challenge, two IB-367 pre-treated groups plus daptomycin or teicoplanin given after challenge, two groups treated with daptomycin or teicoplanin only after challenge, and two control groups without infection or that did not receive any treatment. The main outcome measures were quantitative bacterial culture and analysis of natural killer (NK) cytotoxicity and leukocyte phenotype. The wound, established through the panniculus carnosus muscle of mice, was infected by MRSA. Bacterial cultures of mice receiving antibiotics alone showed a −2 log decrease, whilst those for IB-367 plus daptomycin or teicoplanin showed a −4 log decrease. IB-367 plus daptomycin showed the highest efficacy. The higher antimicrobial effect exerted by IB-367 was associated with increased levels of NK cytotoxicity but not of NK cell number. IB-367 increased the number of both CD11b and Gr-1 cells 3 days after MRSA challenge, whereas both of these leukocyte populations were reduced at 10 days after challenge. Our data suggest that a combination of IB-367 with antibiotic exerts a therapeutic effect and may be useful for the management of staphylococcal wounds.

Comparative analysis of empiric antimicrobial treatments for skin and soft tissue infections in newly hospitalized patients

PURPOSE

Intravenous vancomycin is the standard empiric treatment for complicated skin and soft tissue infections (SSTIs) due to its coverage against methicillin-resistant Staphylococcus aureus (MRSA). The objective of this study was to compare the hospital length of stay (LOS) between vancomycin-treated patients and patients receiving newer anti-MRSA agents. The study also aimed to identify factors associated with therapy change in patients receiving vancomycin on admission.

METHODS

Electronic medical records were used to conduct this retrospective cohort study. The LOS was compared among 5 groups of adult patients with admission diagnoses for SSTI who were initiated on linezolid, daptomycin, ceftaroline, tigecycline, or vancomycin. Survival analysis was used to identify factors associated with therapy change from vancomycin to another study medication.

RESULTS

Vancomycin was prescribed in 1046 (92%) admissions. Although none of the between-group differences in LOS reached statistical significance, there was a trend toward shorter LOS in vancomycin-treated patients compared to linezolid-treated patients (P = .059). Coagulopathy was independently associated with increased likelihood of therapy change from vancomycin (hazard ratio = 4.71; P <.001).

CONCLUSIONS

In the treatment of SSTI, newer agents result in LOS comparable to vancomycin. In patients initiated on vancomycin, therapy change was associated with longer LOS. Coagulopathy was independently associated with increased probability of therapy change.

Activity of short lipopeptides and conventional antimicrobials against planktonic cells and biofilms formed by clinical strains of Staphylococcus aureus

Background: The therapy for staphylococcal skin diseases is facing several difficulties caused by the growth of biofilms and development of resistant strains. Short synthetic lipopeptides designed on the basis of antimicrobial peptide structure seem to provide an alternative to conventional therapy. The purpose of this study was to synthesize a group of lipopeptides and evaluate their antistaphylococcal activity against biofilms formed by clinical strains of Staphylococcus aureus. Results: The compounds exhibited a strong antibiofilm activity against all the isolates. The maturity of the biofilms has shown a well-defined influence on antimicrobial activity of conventional antimicrobials. Discussion: Results showed that the lipopeptides were promising agents as the time of the culture did not greatly affect their activity.

Comparative activity of ceftobiprole against Gram-positive and Gram-negative isolates from Europe and the Middle East: the CLASS study

OBJECTIVES

to assess the in vitro activity of ceftobiprole and comparators against a recent collection of Gram-positive and Gram-negative pathogens, in order to detect potential changes in susceptibility patterns, and to evaluate the Etest assay for ceftobiprole susceptibility testing.

METHODS

contemporary Gram-positive and Gram-negative isolates (excluding extended-spectrum β-lactamase-producing isolates) from across Europe and the Middle East were collected, and their susceptibility to ceftobiprole, vancomycin, teicoplanin, linezolid, ceftazidime and cefepime was assessed using the Etest method. Quality testing [using Etest and broth microdilution (BMD)] was conducted at a central reference laboratory.

RESULTS

some 5041 Gram-positive and 4026 Gram-negative isolates were included. Against Gram-positive isolates overall, ceftobiprole had the lowest MIC50 (0.5 mg/L), compared with 1 mg/L for its comparators (vancomycin, teicoplanin and linezolid). Against methicillin-resistant Staphylococcus aureus, all four agents had a similar MIC90 (2 mg/L), but ceftobiprole had a 4-fold better MIC90 (0.5 mg/L) against methicillin-susceptible strains. Only 38 Gram-positive isolates were confirmed as ceftobiprole resistant. Among Gram-negative strains, 86.9%, 91.7% and 95.2% were susceptible to ceftobiprole, ceftazidime and cefepime, respectively. Pseudomonas aeruginosa was less susceptible to all three antimicrobials than any other Gram-negative pathogen. There was generally good agreement between local Etest results and those obtained at the reference laboratory (for ceftobiprole: 86.8% with Gram-negatives; and 94.7% with Gram-positives), as well as between results obtained by BMD and Etest methods (for ceftobiprole: 98.2% with Gram-negatives; and 98.4% with Gram-positives).

CONCLUSIONS

ceftobiprole exhibits in vitro activity against a wide range of Gram-positive and Gram-negative pathogens, including multidrug-resistant strains. No changes in its known susceptibility profile were identified.

Emerging drugs for complicated skin and skin-structure infections

IMPORTANCE OF THE FILED: With the worldwide surge of MRSA, skin and skin-structure infection (SSTI) treatment has become a challenge for physicians. Cultures and antibiotic susceptibility tests for SSTIs are the rule due to the implication in morbidity and mortality rates associated with MRSA infections. The need for new antibiotics is evident and the effort to decrease antibiotic resistance is a world priority.

AREAS COVERED IN THIS REVIEW

This manuscript accesses the actual treatments and the developing of antibiotics for MRSA SSTIs.

WHAT THE READER WILL GAIN

This is a review of the data on the available and emerging treatments for MRSA SSTIs.

TAKE HOME MESSAGE

There is an unmet medical need for new antibiotics in the new millennium. As physicians, we must assure all appropriate procedures are completed in order to reduce the bacterial resistance, especially for MRSA.

The zwitterionic cell wall teichoic acid of Staphylococcus aureus provokes skin abscesses in mice by a novel CD4+ T-cell-dependent mechanism

Zwitterionic polysaccharide (ZPS) components of the bacterial cell envelope have been shown to exert a major histocompatibility complex (MHC) II-dependent activation of CD4+ T cells, which in turn can modulate the outcome and progression of infections in animal models. We investigated the impact of zwitterionic cell wall teichoic acid (WTA) produced by Staphylococcus aureus on the development of skin abscesses in a mouse model. We also compared the relative biological activities of WTA and capsular polysaccharide (CP), important S. aureus pathogenicity factors, in abscess formation. Expression of both WTA and CP markedly affected the ability of S. aureus to induce skin abscess formation in mice. Purified wild-type zwitterionic WTA was more active in inducing abscess formation than negatively charged mutant WTA or purified CP8. To assess the ability of purified native WTA to stimulate T cell proliferation in vitro, we co-cultivated WTA with human T-cells and antigen presenting cells in the presence and absence of various inhibitors of MHC-II presentation. Wild-type WTA induced T cell proliferation to a significantly greater extent than negatively charged WTA. T cell activation was dependent on the presentation of WTA on MHC II, since inhibitors of MHC II-dependent presentation and antibodies to MHC II significantly reduced T cell proliferation. T cells activated in vitro with wild-type WTA, but not negatively charged WTA, induced abscess formation when injected subcutaneously into wild-type mice. CD4−/− mice similarly injected with WTA failed to develop abscesses. Our results demonstrate that the zwitterionic WTA of S. aureus induces CD4+ T-cell proliferation in an MHCII-dependent manner, which in turn modulates abscess formation in a mouse skin infection model. An understanding of this novel T cell-dependent host response to staphylococcal abscess formation may lead to the development of new strategies to combat S. aureus skin and soft tissue infections.