Clinical and bacteriological efficacy of twice daily topical retapamulin ointment 1% in the management of impetigo and other uncomplicated superficial skin infections

Emerging Treatment Strategies for Impetigo in Endemic and Nonendemic Settings: A Systematic Review

PURPOSE

Impetigo affects approximately 162 million children worldwide at any given time. Lack of consensus on the most effective treatment strategy for impetigo and increasing antibiotic resistance continue to drive research into newer and alternative treatment options. We conducted a systematic review to assess the effectiveness of new treatments for impetigo in endemic and nonendemic settings.

METHODS

We searched PubMed, MEDLINE, CINAHL, Web of Science, and Embase via Scopus for studies that explored treatments for bullous, nonbullous, primary, and secondary impetigo published between August 1, 2011, and February 29, 2020. We also searched online trial registries and hand-searched the reference lists of the included studies. We used the revised Cochrane risk of bias (version 2.0) tool for randomized trials and the National Heart, Lung, and Blood Institute for nonrandomized uncontrolled studies to assess the risk of bias.

FINDINGS

We included 10 studies that involved 6651 participants and reported on 9 treatments in the final analysis. Most clinical trials targeted nonbullous impetigo or did not specify this. The risk of bias varied among the studies. In nonendemic settings, ozenoxacin 1% cream appeared to have the strongest evidence base compared with retapamulin and a new minocycline formulation. In endemic settings, oral co-trimoxazole and benzathine benzylpenicillin G injection were equally effective in the treatment of severe impetigo. Mass drug administration intervention emerged as a promising public health strategy to reduce the prevalence of impetigo in endemic settings.

IMPLICATIONS

This review highlights the limited research into new drugs used for the treatment of impetigo in endemic and nonendemic settings. Limited recent evidence supports the use of topical ozenoxacin or retapamulin for impetigo treatment in nonendemic settings, whereas systemic antibiotics and the mass drug administration strategy have evidence for use in endemic settings. Given the troubling increase in resistance to existing treatments, there is a clear need to ensure the judicious use of antibiotics and to develop new treatments and alternative strategies; this is particularly important in endemic settings. PROSPERO identifier: CRD42020173042.

A comparative review of current topical antibiotics for impetigo

INTRODUCTION

Impetigo is a superficial bacterial skin infection largely affecting the pediatric population. The objective of this review is to provide a comparison of mechanism of action, efficacy and safety of the available topical antibiotics for impetigo.

AREAS COVERED

Randomized clinical trials that evaluated the use of topical antibiotics for treatment of impetigo were included. Two thousand eighty-nine studies were initially identified, and five randomized clinical trials met the criteria for further analysis.

EXPERT OPINION

Topical antibiotics had greater resolution of impetigo in comparison to vehicle in these pivotal clinical trials. Adverse events were minimal, with the most common being pruritus at the application site. Cost or insurance coverage may be a limiting factor in choosing the best therapeutic agent, with mupirocin ointment having the lowest cost. Mupirocin has shown clinical efficacy against MRSA but a bacterial culture is recommended to rule out resistance. Ozenoxacin and retapamulin are effective alternatives but may entail higher cost. Retapamulin is indicated for lesions of impetigo that are colonized by MSSA and streptococcus S. pyogenes but not MRSA based on clinical efficacy of phase III trials. Fusidic acid, available in other countries, is a non-FDA approved medication although rising resistance rates represent a growing concern.

Intolerable Burden of Impetigo in Endemic Settings: A Review of the Current State of Play and Future Directions for Alternative Treatments

Impetigo (school sores) is a common superficial bacterial skin infection affecting around 162 million children worldwide, with the highest burden in Australian Aboriginal children. While impetigo itself is treatable, if left untreated, it can lead to life-threatening conditions, such as chronic heart and kidney diseases. Topical antibiotics are often considered the treatment of choice for impetigo, but the clinical efficacy of these treatments is declining at an alarming rate due to the rapid emergence and spread of resistant bacteria. In remote settings in Australia, topical antibiotics are no longer used for impetigo due to the troubling rise of antimicrobial resistance, demanding the use of oral and injectable antibiotic therapies. However, widespread use of these agents not only contributes to existing resistance, but also associated with adverse consequences for individuals and communities. These underscore the urgent need to reinvigorate the antibiotic discovery and alternative impetigo therapies in these settings. This review discusses the current impetigo treatment challenges in endemic settings in Australia and explores potential alternative antimicrobial therapies. The goals are to promote intensified research programs to facilitate effective use of currently available treatments, as well as developing new alternatives for impetigo.

Impetigo Animal Models: A Review of Their Feasibility and Clinical Utility for Therapeutic Appraisal of Investigational Drug Candidates

Impetigo (school sores), a superficial skin infection commonly seen in children, is caused by the gram-positive bacteria Staphylococcus aureus and/or Streptococcus pyogenes. Antibiotic treatments, often topical, are used as the first-line therapy for impetigo. The efficacy of potential new antimicrobial compounds is first tested in in vitro studies and, if effective, followed by in vivo studies using animal models and/or humans. Animal models are critical means for investigating potential therapeutics and characterizing their safety profile prior to human trials. Although several reviews of animal models for skin infections have been published, there is a lack of a comprehensive review of animal models simulating impetigo for the selection of therapeutic drug candidates. This review critically examines the existing animal models for impetigo and their feasibility for testing the in vivo efficacy of topical treatments for impetigo and other superficial bacterial skin infections.

Traditional and advanced therapeutic modalities for wounds in the paediatric population: an evidence-based review

OBJECTIVE

Children can have non-healing wounds due to a wide range of pathologies, including epidermolysis bullosa (EB), pilonidal disease and Stevens-Johnson syndrome, with some causes being iatrogenic, including extravasation injuries and medical device-related hospital-acquired pressure ulcers. Furthermore, paediatric wounds are vastly different from adult wounds and therefore require a different treatment approach. While there are numerous types of dressings, topical remedies, and matrices with high-tier evidence to support their use in adults, evidence is scarce in the neonatal and paediatric age groups. The purpose of this review is to discuss the basic principles in paediatric wound management, as well as to present new treatment findings published in the literature to date. The benefits and risks of using different types of debridement are discussed in this review. Various topical formulations are also described, including the need to use antibiotics judiciously.

METHOD

Databases were searched for relevant sources including Pubmed, Embase, Web of Science and DynaMed. Search terms used included 'wound care', 'wound management', 'paediatrics', 'children', 'skin substitutes', and 'grafts'. Additionally, each treatment and disease entity was searched for relevant sources, including, for example: 'Apligraf', 'dermagraft', 'Manuka honey', 'antibiotic', 'timolol', and 'negative pressure wound therapy' (NPWT).

RESULTS

Amniotic membrane living skin equivalent is a cellular matrix that has been reportedly successful in treating paediatrics wounds and is currently under investigation in randomised clinical trials. Helicoll is an acellular matrix, which shows promise in children with recessive dystrophic EB. NPWT may be used as a tool to accelerate wound closure in children; however, caution must be taken due to limited evidence to support its safety and efficacy in the paediatric patient population. Integra has been reported as a useful adjunctive treatment to NPWT as both may act synergistically. Hospitalised children and neonates frequently have pressure ulcers, which is why prevention in this type of wound is paramount.

CONCLUSION

Advancements in wound care are rapidly expanding. Various treatments for non-healing wounds in paediatric and neonatal patients have been reported, but high tier evidence in these populations is scarce. We hope to shed light on existing evidence regarding the different therapeutic modalities, from debridement techniques and dressing types to tissue substitutes and topical remedies. There have been promising results in many studies to date, but RCTs involving larger sample sizes are necessary, in order to determine the specific role these innovative agents play in paediatric wounds and to identify true safety and efficacy.

Are Antimicrobial Peptide Dendrimers an Escape from ESKAPE?

Significance: The crisis of antimicrobial resistance (AMR) increases dramatically despite all efforts to use available antibiotics or last resort antimicrobial agents. The spread of the AMR, declared as one of the most important health-related issues, warrants the development of new antimicrobial strategies. Recent Advances: Antimicrobial peptides (AMPs) and AMP dendrimers (AMPDs), as well as polymer dendrimers are relatively new and promising strategies with the potential to overcome drug resistance issues arising in ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) colonizing chronic wounds. Critical Issues: AMPs-AMPDs suffer from limited efficacy, short-lasting bioactivity, and concerns of toxicity. To circumvent these drawbacks, their covalent coupling to biopolymers and/or encapsulation into different drug carrier systems is investigated, with a special focus on topical applications. Future Directions: Scientists and the pharmaceutical industry should focus on this challenging subject to either improve the activity of existing antimicrobial agents or find new drug candidates. The focus should be put on the discovery of new drugs or the combination of existing drugs for a better synergy, taking into account all kinds of wounds and existing pathogens, and more specifically on the development of next-generation antimicrobial peptides, encompassing the delivery carrier toward improved pharmacokinetics and efficacy.