Treatment of Staphylococcus aureus colonization in atopic dermatitis decreases disease severity

Sodium Hypochlorite/Salicylic Acid Shampoo for Treatment of Canine Staphylococcal Pyoderma

The emergence of methicillin-resistant Staphylococcus pseudintermedius has increased the interest in topical therapy for treating canine pyoderma. Shampooing with chlorhexidine followed by dilute bleach rinses are often recommended, but household bleach can dry the skin and is unpleasant to use. A shampoo formulated with sodium hypochlorite and salicylic acid was evaluated as sole therapy for dogs with superficial pyoderma associated with S. pseudintermedius, including methicillin-resistant strains. Client-owned dogs were recruited based on positive culture for methicillin-resistant staphylococci or prior failure of pyoderma to respond to antibiotics. This prospective, open-label pilot study assessed the efficacy of the shampoo when used three times weekly for 4 wk. Dogs were evaluated at baseline and at 2 and 4 wk by cytology, clinical examination, and owner assessment. Digital images were also obtained. Baseline bacterial counts, clinical assessments and owner scores were significantly improved at 2 and 4 wk. Clients completing the study reported excellent lathering and dispersion, reduction in odor, and brightening of white and light coats. No owners reported skin dryness or other adverse events during the study. We conclude that this shampoo containing sodium hypochlorite in a vehicle that avoids skin drying is an effective treatment for canine pyoderma.

Prevention Strategies for Recurrent Community-Associated Staphylococcus aureus Skin and Soft Tissue Infections

PURPOSE OF REVIEW

Staphylococcus aureus skin and soft tissue infections (SSTI) are a major source of morbidity. More than half of patients experiencing SSTI will have at least one recurrent infection. These infections frequently cluster in households. Given the burden these infections pose to patients and healthcare, prevention strategies are of major clinical importance and represent an active area of research. Bacterial colonization is frequently an early and critical step in the pathogenesis of infection. As such, strategies to prevent reinfection have aimed to decrease staphylococcal colonization of the skin and mucus membranes, a process referred to as decolonization.

RECENT FINDINGS

Treatment of acute SSTI with incision and drainage and systemic antibiotics is the mainstay of therapy for healing of the acute infection. Systemic antibiotics also provide benefit through reduced incidence of recurrent SSTI. Education for patients and families regarding optimization of personal and household hygiene measures, and avoidance of sharing personal hygiene items, is an essential component in prevention efforts. For patients experiencing recurrent SSTI, or in households in which multiple members have experienced SSTI, decolonization should be recommended for all household members. A recommended decolonization regimen includes application of intranasal mupirocin and antiseptic body washes with chlorhexidine or dilute bleach water baths. For patients who continue to experience recurrent SSTI, periodic decolonization should be considered. Personal decolonization with topical antimicrobials and antiseptics reduces the incidence of recurrent S. aureus SSTI. Future avenues for investigation include strategies for household environmental decontamination as well as manipulation of the host microbiota.

Topical, systemic and biologic therapies in hidradenitis suppurativa: pathogenic insights by examining therapeutic mechanisms

Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the skin, manifesting in chronic, recurrent painful pustules, nodules, boils and purulent draining abscesses. Our current understanding of the pathogenesis of the disease is incomplete. This review aims to identify available treatment options in HS and discuss the pharmacological mechanisms through which such agents function. Identifying common pathways may inform our understanding of the pathogenesis of HS as well as identify future therapeutic targets. The pharmacological mechanisms implicated in topical therapies, antibiotic, hormonal, systemic immunomodulatory and biologic therapies for HS are discussed. Significant differences exist between agents and implicated pathways in therapy for mild and severe disease. This is an expression of the possible dichotomy in inflammatory pathways (and treatment responses) in HS. Studies involving monoclonal antibodies provide the greatest insight into what these specific mechanisms may be. Their variable levels of clinical efficacy compared with placebo bolsters the suggestion that differential inflammatory pathways may be involved in different presentations and severity of disease. Nuclear factor kappa B (NF-κB), tumor necrosis factor (TNF)-α and other innate immune mechanisms are strongly represented in treatments which are effective in mild to moderate disease in the absence of scarring or draining fistulae, however complex feed-forward mechanisms in severe disease respond to interleukin (IL)-1 inhibition but are less likely to respond to innate immune inhibition (through NF-κB or TNF-α) alone. It is unclear whether IL-17 inhibition will parallel TNF-α or IL-1 inhibition in effect, however it is plausible that small molecule targets (Janus kinase1 and phosphodiesterase 4) may provide effective new strategies for treatment of HS.

Current therapeutic paradigm in pediatric atopic dermatitis: Practical guidance from a national expert panel

INTRODUCTION AND OBJECTIVES

Atopic dermatitis (AD) is the most common cutaneous inflammatory disease in both adults and children. Although emerging therapeutic approaches are being investigated for the management of pediatric AD, it still needs to be managed with conventional treatments. This consensus document is aimed at providing an update on general management and therapies of pediatric AD, defining practical recommendations for using both topical and systemic agents.

MATERIAL AND METHODS

A panel of experts consisting of dermatologists and pediatricians were convened in order to define statements, through a Delphi process, standardizing the management of AD in pediatric subjects in a real-world setting.

RESULTS

A set of practical recommendations obtaining an at least 75% agreement was presented.

CONCLUSIONS

This set of practical recommendations represents a simple and fast snapshot on the pediatric use of common anti-AD therapeutics.

Staphylococcus aureus from atopic dermatitis skin accumulates in the lysosomes of keratinocytes with induction of IL-1α secretion via TLR9

BACKGROUND

Staphylococcus aureus (S. aureus) is frequently detected in the skin of patients with atopic dermatitis (AD), and involved in the flare of AD. There are some evidence-specific strains of S. aureus affect the severity of AD. However, the mechanism of predominant colonization and the aggravation of dermatitis by certain strains of S. aureus in the patients with AD are still unknown.

OBJECTIVE

To reveal the characteristics of S. aureus from patients with AD (S. aureus-AD), we analyzed the interaction of S. aureus-AD and keratinocytes in comparison with those of S. aureus laboratory strains (S. aureus-stand.).

METHODS

We stimulated HaCaT cells, keratinocyte cell line, and human epidermal keratinocytes by heat-killed S. aureus strains, then evaluated immune response of keratinocytes by ELISA, immunofluorescence staining, and flow cytometry.

RESULTS

Upon incubation with keratinocytes, three out of four strains of heat-killed S. aureus-AD were strongly agglutinated inside the cytoplasm. In the cells, they are located in lysosomes and promoted the secretion of interleukin-1α (IL-1α). These reactions were not observed by any of four strains of S. aureus-stand. and S. epidermidis and were abolished by the treatment of S. aureus with proteinase K. Moreover, the IL-1α secretion was diminished by the inhibition of Toll-like receptor 9 (TLR9).

CONCLUSION

S. aureus-AD accumulates in lysosome of keratinocytes by means of bacterial cell wall proteins and induces IL-1α via TLR9.

Proderm technology: a water- based lipid delivery system for dermatitis that penetrates viable epidermis and has antibacterial effects

Background

A defective skin barrier and bacterial colonization are two important factors in maintenance and progression of atopic dermatitis and chronic allergic/irritant hand dermatitis. A water-based lipid delivery system containing physiologic lipids was previously shown to be a useful adjunct in the treatment of hand dermatitis. We tested the ability of this formulation to penetrate into the viable epidermis and in addition assessed its antibacterial properties.

Methods

Epidermal penetration of the product was assessed by fluorescence microscopy. Recovery of Escherichia coli and Staphylococcus aureus MRSA from skin treated with Neosalus® foam was quantified.

Results

Components of Neosalus® penetrated the stratum corneum and were distributed throughout the viable epidermis. Neosalus® significantly decreased recovery of both Staphylococcus aureus and Escherichia coli from the skin surface.

Conclusions

The ability of components of Neosalus® to be taken up into the viable epidermis and potentially made available for incorporation into the barrier lipids, combined with antibacterial properties, indicate that this formulation may be valuable not only in chronic hand dermatitis, but also in various other forms of dermatitis.

Trial registration

Current Controlled Trials ISRCTN18191379, 28/12/2018, retrospectively registered.

Comparison of bleach, acetic acid, and other topical anti-infective treatments in pediatric atopic dermatitis: A retrospective cohort study on antibiotic exposure

BACKGROUND/OBJECTIVES

Skin infection is common in atopic dermatitis (AD), often necessitating treatment with systemic antibiotics. Topical adjunctive therapies such as dilute bleach baths are increasingly recommended, and topical dilute acetic acid (AA) has not been widely studied. The objective of this study was to evaluate whether various topical anti-infective bathing recommendations were associated with decreased systemic antibiotic exposure in pediatric AD, as well as evaluate topical anti-infective recommendations over time within our institution.

METHODS

Clinical data were extracted from charts of pediatric patients from 1/1/2000 to 12/31/2005 and 1/1/2009 to 12/31/2014 who visited outpatient dermatology clinics at Mayo Clinic, Rochester, a tertiary referral center. Recommendations for topical anti-infectives (dilute AA, dilute bleach, other, or none) at any time after patient had clinically proven or suspected AD superinfection were recorded as exposures to topical anti-infective. Primary outcome was the number of systemic antibiotic courses in a 1-year period.

RESULTS

Of 1111 patients with AD, 753 met inclusion criteria (303 in 2000-2005; 450 in 2009-2014). Of these, 351 (46.6%) had culture-proven or clinically suspected superinfection. Topical anti-infective recommendations increased between the time periods (23.3% to 79.2%; P < 0.001) and number of courses of systemic antibiotics decreased (1.9 per year vs 1.5 per year, P = 0.010). Number of systemic antibiotic courses did not differ between those who received bathing recommendations and those who did not, nor between different anti-infective groups (P = 0.398).

CONCLUSIONS

Practice behaviors have changed, and topical anti-infectives are now commonly recommended. Neither dilute AA nor bleach baths were associated with fewer subsequent exposures to systemic antibiotics in the treatment of pediatric AD.

Decolonization of Staphylococcus aureus in Healthcare: A Dermatology Perspective

The bacterium Staphylococcus aureus is responsible for significant morbidity, mortality, and financial burden in healthcare. It easily colonizes susceptible patients and can cause recurrent infections, especially in populations at risk. In addition to treating sequelae of infections, there is a growing body of literature aimed at decolonizing susceptible patients in order to prevent infection and also to prevent spread. Such strategies are widely employed in surgical, intensive care, and hospitalist fields. Staphylococcus aureus involvement has been implicated in the pathogenesis and persistence of many dermatologic diseases that are treated in the outpatient setting. This review serves to summarize current evidence for the management of Staphylococcus aureus colonized patients, as well as the evidence available for decolonization. We further characterize the role that colonization may play in atopic dermatitis, recurrent infections, hand eczema, cutaneous T-cell lymphoma, and also in surgical infections after Mohs surgery.

Dismissing the fallacies of childhood eczema management: case scenarios and an overview of best practices

BACKGROUND

Eczema or atopic dermatitis (AD) is a common relapsing childhood dermatologic illness. Treatment of AD is primarily topical with emollients and corticosteroid/calcineurin inhibitor, which is efficacious for the majority of patients. However, AD is often complicated and difficult to manage in many Asian cities. Effective therapy is impeded by fallacies in the following aspects: (1) mistrust and unrealistic expectations about Western medicine, (2) skin care and allergy treatment, (3) ambiguity about optimal bathing and moisturizing, (4) hesitation and phobias about the usage of adequate topical corticosteroid and immunomodulatory therapies, (5) food and aeroallergen avoidance and dietary supplementation, and (6) complementary and alternative therapies.

METHODS AND RESULTS

Eleven anonymized case scenarios are described to illustrate issues associated with these fallacies. A literature review is performed and possible solutions to handle or dismiss these fallacies are discussed.

CONCLUSIONS

The first step in patient care is to accurately assess the patient and the family to evaluate possible concerns, anxiety, and phobias that could impede therapeutic efficacy. Education about the disease should be individualized. Conflicting recommendations on the usage of topical steroid have a detrimental effect on management outcomes, which must be avoided.

Consensus-based European guidelines for treatment of atopic eczema (atopic dermatitis) in adults and children: part II

This guideline was developed as a joint interdisciplinary European project, including physicians from all relevant disciplines as well as patients. It is a consensus-based guideline, taking available evidence from other guidelines, systematic reviews and published studies into account. This second part of the guideline covers antimicrobial therapy, systemic treatment, allergen-specific immunotherapy, complementary medicine, psychosomatic counselling and educational interventions, whereas the first part covers methods, patient perspective, general measures and avoidance strategies, basic emollient treatment and bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy. Management of AE must consider the individual clinical variability of the disease. Systemic immunosuppressive treatment with cyclosporine, methotrexate, azathioprine and mycophenolic acid is established option for severe refractory cases, and widely available. Biologicals targeting the T helper 2 pathway such as dupilumab may be a safe and effective, disease-modifying alternative when available. Oral drugs such as JAK inhibitors and histamine 4 receptor antagonists are in development. Microbial colonization and superinfection may cause disease exacerbation and can require additional antimicrobial treatment. Allergen-specific immunotherapy with aeroallergens may be considered in selected cases. Psychosomatic counselling is recommended especially in stress-induced exacerbations. Therapeutic patient education ('Eczema school') is recommended for children and adult patients. General measures, basic emollient treatment, bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy have been addressed in the first part of the guideline.

Consensus-based European guidelines for treatment of atopic eczema (atopic dermatitis) in adults and children: part I

This guideline was developed as a joint interdisciplinary European project, including physicians from all relevant disciplines as well as patients. It is a consensus-based guideline, taking available evidence from other guidelines, systematic reviews and published studies into account. This first part of the guideline covers methods, patient perspective, general measures and avoidance strategies, basic emollient treatment and bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy, whereas the second part covers antimicrobial therapy, systemic treatment, allergen-specific immunotherapy, complementary medicine, psychosomatic counselling and educational interventions. Management of AE must consider the individual clinical variability of the disease; highly standardized treatment rules are not recommended. Basic therapy is focused on treatment of disturbed barrier function by hydrating and lubricating topical treatment, besides further avoidance of specific and unspecific provocation factors. Topical anti-inflammatory treatment based on glucocorticosteroids and calcineurin inhibitors is used for flare management and for proactive therapy for long-term control. Topical corticosteroids remain the mainstay of therapy, whereas tacrolimus and pimecrolimus are preferred in sensitive skin areas and for long-term use. Topical phosphodiesterase inhibitors may be a treatment alternative when available. Adjuvant therapy includes UV irradiation, preferably with UVB 311 nm or UVA1. Pruritus is targeted with the majority of the recommended therapies, but some patients may need additional antipruritic therapy. Antimicrobial therapy, systemic anti-inflammatory treatment, immunotherapy, complementary medicine and educational intervention will be addressed in part II of the guideline.

Temporal variation of Staphylococcus aureus clonal complexes in atopic dermatitis: a follow-up study

BACKGROUND

A strong link between disease severity and Staphylococcus aureus colonization of the skin has been reported in patients with atopic dermatitis (AD).

OBJECTIVES

To examine temporal variations in S. aureus colonization and S. aureus CC type in patients with AD, and to investigate links to disease severity, skin barrier properties and filaggrin gene (FLG) mutations.

METHODS

This was a follow-up study of a cohort of 101 adult patients with AD recruited from an outpatient clinic. Bacterial swabs were taken at baseline and follow-up from lesional skin, nonlesional skin and the nose. Swabs positive for S. aureus were characterized by spa and the respective clonal complex (CC) type was assigned. Patients were characterized with respect to disease severity [Scoring Atopic Dermatitis (SCORAD)], skin barrier properties [transepidermal water loss (TEWL), pH] and FLG mutations.

RESULTS

In total, 63 patients participated in a follow-up visit. Twenty-seven patients (43%) were colonized at both visits, 27 were colonized at only one visit and nine (14%) were not colonized at either visit. Of patients colonized at both visits, 52% remained colonized with the same CC type at follow-up. Change in CC type was related to an increase in SCORAD of 10·7 points; patients who carried the same CC type had a reduction in SCORAD of 4·4 points. Significantly higher skin pH was found in patients colonized at both visits, while change in CC type was not related to TEWL, pH or FLG mutations.

CONCLUSIONS

The data indicate that temporal variation in S. aureus CC type is linked to flares of the disease.

Recent Developments in Atopic Dermatitis

Atopic dermatitis (AD) is a bothersome and common skin disease affecting ∼10.7% of children in the United States. This skin condition significantly decreases quality of life in not only patients, but in their families as well. Pediatricians are often the first physicians to diagnose and manage these patients and thus are relied on by families to answer questions about this disease. AD is complex, multifactorial, and has historically had limited therapeutic options, but the landscape of this disease is now rapidly changing. Pathways contributing to the pathogenesis of this disease are continually being discovered, and new therapies for AD are being developed at an unprecedented rate. With this article, we will review the current guidelines regarding the management of AD, outline updates in the current understanding of its pathophysiology, and highlight novel developments available for the treatment of this burdensome disease.

Atopic dermatitis

Atopic dermatitis (AD) is a common, chronic skin disorder that can significantly impact the quality of life of affected individuals as well as their families. Although the pathogenesis of the disorder is not completely understood, it appears to result from the complex interplay between defects in skin barrier function, environmental and infectious agents, and immune dysregulation. There are no diagnostic tests for AD; therefore, the diagnosis is based on specific clinical criteria that take into account the patient's history and clinical manifestations. Successful management of the disorder requires a multifaceted approach that involves education, optimal skin care practices, anti-inflammatory treatment with topical corticosteroids and/or topical calcineurin inhibitors, the management of pruritus, and the treatment of skin infections. Systemic immunosuppressive agents may also be used, but are generally reserved for severe flare-ups or more difficult-to-control disease. Topical corticosteroids are the first-line pharmacologic treatments for AD, and evidence suggests that these agents may also be beneficial for the prophylaxis of disease flare-ups. Although the prognosis for patients with AD is generally favourable, those patients with severe, widespread disease and concomitant atopic conditions, such as asthma and allergic rhinitis, are likely to experience poorer outcomes.

Epithelial barrier dysfunctions in atopic dermatitis: a skin-gut-lung model linking microbiome alteration and immune dysregulation

BACKGROUND

Atopic dermatitis is a systemic disorder characterized by abnormal barrier function across multiple organ sites. Causes of epidermal barrier breakdown are complex and driven by a combination of structural, genetic, environmental and immunological factors. In addition, alteration in microflora diversity can influence disease severity, duration, and response to treatment. Clinically, atopic dermatitis can progress from skin disease to food allergy, allergic rhinitis, and later asthma, a phenomenon commonly known as the atopic march. The mechanism by which atopic dermatitis progresses towards gastrointestinal or airway disease remains to be elucidated.

OBJECTIVES

This review addresses how epithelial dysfunction linking microbiome alteration and immune dysregulation can predispose to the development of the atopic march.

METHODS

A literature search was conducted using the PubMed database for relevant articles with the keywords 'atopic dermatitis', 'epithelial barrier', 'skin', 'gut', 'lung', 'microbiome' and 'immune dysregulation'.

RESULTS

Initial disruption in the skin epidermal barrier permits allergen sensitization and colonization by pathogens. This induces a T helper 2 inflammatory response and a thymic stromal lymphopoietin-mediated pathway that further promotes barrier breakdown at distant sites, including the intestinal and respiratory tract.

CONCLUSIONS

As there are no immediate cures for food allergy or asthma, early intervention aimed at protecting the skin barrier and effective control of local and systemic inflammation may improve long-term outcomes and reduce allergen sensitization in the airway and gut.

Breast abscess caused by Staphylococcus aureus in 2 adolescent girls with atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease in children. Patients with AD experience a high rate of colonization of the skin surface by Staphylococcus aureus. Because of a skin barrier defect, there is a potential risk of staphylococcal invasive infection in patients with AD. Here, we present 2 cases of breast abscess caused by S. aureus in 2 adolescent girls with severe AD. Methicillin-sensitive S. aureus was identified from the breast abscess material. They were treated with appropriate antibiotics, however surgical drainage of the abscess was needed in case 1. Identical strains were found from the breast abscess material as well as the lesional and the nonlesional skin of the patients through matrixassisted laser desorption/ionization time-of-flight analysis. We characterized the differential abundance of Firmicutes phylum in patients' skin in microbiota analysis. In particular, S. aureus, a member of Firmicutes, differed significantly between the lesional and the normal-appearing skin. Our cases demonstrate the potential severity of bacterial deep tissue infection in AD and the dysbiosis of skin microbiota may be involved in inflammation in AD.

Skin microbiota-host interactions

The skin is a complex and dynamic ecosystem that is inhabited by bacteria, archaea, fungi and viruses. These microbes-collectively referred to as the skin microbiota-are fundamental to skin physiology and immunity. Interactions between skin microbes and the host can fall anywhere along the continuum between mutualism and pathogenicity. In this Review, we highlight how host-microbe interactions depend heavily on context, including the state of immune activation, host genetic predisposition, barrier status, microbe localization, and microbe-microbe interactions. We focus on how context shapes the complex dialogue between skin microbes and the host, and the consequences of this dialogue for health and disease.

Severe Atopic Dermatitis in Children

PURPOSE OF REVIEW

Severe atopic dermatitis (AD) in childhood leads to significant morbidity including psychosocial problems and infectious complications. There are only a few approved treatment options for these patients. These include topical corticosteroids and tacrolimus ointment, which are associated with potential side effects.

RECENT FINDINGS

In order to find better and safer treatments, further understanding of AD mechanisms is needed. Primary skin barrier defects play an important role in the pathogenesis of AD. In addition, the suppression of skin barrier functions by Th2 inflammation also plays an important role in the persistence and recurrence of AD. Cytokines in the Th2 pathway, which includes IL-4, IL-13, TSLP, IL-25, IL-31, and IL-33, are potential therapeutic targets in AD. Other potential targets of AD are Janus kinase, phospholipase A2, aryl hydrocarbon receptor, and skin microbiota. A better understanding of the pathogenesis of AD will provide future direction for treatment.

Significance of Skin Barrier Dysfunction in Atopic Dermatitis

The epidermis contains epithelial cells, immune cells, and microbes which provides a physical and functional barrier to the protection of human skin. It plays critical roles in preventing environmental allergen penetration into the human body and responsing to microbial pathogens. Atopic dermatitis (AD) is the most common, complex chronic inflammatory skin disease. Skin barrier dysfunction is the initial step in the development of AD. Multiple factors, including immune dysregulation, filaggrin mutations, deficiency of antimicrobial peptides, and skin dysbiosis contribute to skin barrier defects. In the initial phase of AD, treatment with moisturizers improves skin barrier function and prevents the development of AD. With the progression of AD, effective topical and systemic therapies are needed to reduce immune pathway activation and general inflammation. Targeted microbiome therapy is also being developed to correct skin dysbiosis associated with AD. Improved identification and characterization of AD phenotypes and endotypes are required to optimize the precision medicine approach to AD.

Topical Hypochlorite and Skin Acidification Improves Erythroderma of Omenn Syndrome

We describe a case of Omenn syndrome displaying exudative erythroderma and other characteristic features, including alopecia, absent B and naïve T cells, hyper immunoglobulin E levels, and eosinophilia. A pathogenic recombination-activating RAG1 homozygous genetic mutation confirmed the diagnosis. She required frequent antibiotics at both treatment and prophylactic doses, which alone did not control her erythroderma, but her high risk of infection precluded the use of systemic agents such as cyclosporine, which would further suppress her already severely compromised immune system. Thrice-weekly topical dilute hypochlorite compresses, combined with skin acidification with a low pH emollient, were initiated to control inflammation and for cutaneous bacterial prophylaxis. She demonstrated a marked improvement in her erythroderma within days after treatment initiation. Further improvement continued with the addition of systemic corticosteroids, with resolution of erythroderma after her first dose. This case reveals for the first time that dilute topical hypochlorite and skin pH restoration holds promise to control severe dermatitis associated with immunodeficiency and inflammatory syndromes with minimal side effects.

Staphylococcus aureus and Staphylococcus epidermidis strain diversity underlying pediatric atopic dermatitis

The heterogeneous course, severity, and treatment responses among patients with atopic dermatitis (AD; eczema) highlight the complexity of this multifactorial disease. Prior studies have used traditional typing methods on cultivated isolates or sequenced a bacterial marker gene to study the skin microbial communities of AD patients. Shotgun metagenomic sequence analysis provides much greater resolution, elucidating multiple levels of microbial community assembly ranging from kingdom to species and strain-level diversification. We analyzed microbial temporal dynamics from a cohort of pediatric AD patients sampled throughout the disease course. Species-level investigation of AD flares showed greater Staphylococcus aureus predominance in patients with more severe disease and Staphylococcus epidermidis predominance in patients with less severe disease. At the strain level, metagenomic sequencing analyses demonstrated clonal S. aureus strains in more severe patients and heterogeneous S. epidermidis strain communities in all patients. To investigate strain-level biological effects of S. aureus, we topically colonized mice with human strains isolated from AD patients and controls. This cutaneous colonization model demonstrated S. aureus strain-specific differences in eliciting skin inflammation and immune signatures characteristic of AD patients. Specifically, S. aureus isolates from AD patients with more severe flares induced epidermal thickening and expansion of cutaneous T helper 2 (T_H2) and T_H17 cells. Integrating high-resolution sequencing, culturing, and animal models demonstrated how functional differences of staphylococcal strains may contribute to the complexity of AD disease.

Pathophysiology and Management of Mild to Moderate Pediatric Atopic Dermatitis

Atopic dermatitis (AD), or eczema, is a chronic inflammatory skin condition characterized by relapsing pruritic and dry, scaly lesions. AD affects 10% to 20% of children in the United States and significantly affects the quality of life of patients and their families. Primary care providers (PCPs) are often the first point of contact for the management of AD symptoms. As many as 70% of patients with mild to moderate disease can be managed by a PCP, underscoring the need for these providers to understand basic AD pathophysiology and current standards of care. This article will discuss the basic principles of AD diagnosis and management that PCPs need to optimize patient care, including AD pathogenesis, appropriate use of currently available topical therapies, basic skin care practices, and patient/caregiver counseling points. This article is sponsored by Spire Learning and supported by an educational grant from Pfizer Inc.

The human skin microbiome

Functioning as the exterior interface of the human body with the environment, skin acts as a physical barrier to prevent the invasion of foreign pathogens while providing a home to the commensal microbiota. The harsh physical landscape of skin, particularly the desiccated, nutrient-poor, acidic environment, also contributes to the adversity that pathogens face when colonizing human skin. Despite this, the skin is colonized by a diverse microbiota. In this Review, we describe amplicon and shotgun metagenomic DNA sequencing studies that have been used to assess the taxonomic diversity of microorganisms that are associated with skin from the kingdom to the strain level. We discuss recent insights into skin microbial communities, including their composition in health and disease, the dynamics between species and interactions with the immune system, with a focus on Propionibacterium acnes, Staphylococcus epidermidis and Staphylococcus aureus.

Immunologic, microbial, and epithelial interactions in atopic dermatitis

OBJECTIVE

To provide an overview of studies contributing to the understanding of immunologic, microbial, and epithelial interactions in atopic dermatitis.

DATA SOURCES

PubMed literature review (2000-2017) and meeting abstracts from recent international dermatology conferences.

STUDY SELECTIONS

Articles discussing primarily human disease.

RESULTS

Clinical studies showed that atopic dermatitis is a type 2 immune-centered disease with a systemic inflammatory component but with heterogeneous treatment responses. This suggests that other factors are likely involved in shaping the skin disease phenotype, including microbial dysbiosis and epidermal barrier dysfunction.

CONCLUSION

Recent clinical investigation has significantly expanded our knowledge on disease pathogenesis in atopic dermatitis, and current and future clinical trials will most likely further help to elucidate this complex, heterogeneous skin disease.

Increasing rate of daptomycin non-susceptible strains of Staphylococcus aureus in patients with atopic dermatitis

Introduction

Daptomycin is a cyclic lipopeptide that is bactericidal against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), vancomycin-intermediate S. aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains. Daptomycin exerts its antimicrobial effect by a calcium-dependent interaction with the cytoplasmic membrane resulting in depolarization, ion loss and rapid cell death. Unfortunately, loss of daptomycin susceptibility in S. aureus in the clinical setting has been noted.

Aim

To evaluate the susceptibility profile to daptomycin among S. aureus strains isloted from patients with atopic dermatitis (AD). Another point was to correlate the results obtained by broth microdilution method and Etest, which is commonly applied in clinical setting.

Material and methods

One hundred patients with the diagnosis of atopic dermatitis were microbiologically assessed for the carriage of S. aureus. Antimicrobial susceptibility tests were performed using broth-microdilution (BMD) and Etests for daptomycin.

Results

Staphylococcus aureus strains were isolated from the majority of our patients, either from the skin (73%) or the anterior nares (75%). Six of the 100 nasal swabs (6%) and 5 of the 100 skin swabs (5%) were positive for methicillin-resistant Staphylococcus aureus (MRSA). A total of 81 of 148 (54.7%) daptomycin non-susceptible isolates of S. aureus were identified by BMD. Only 19 of 81 were also classified as non-susceptible by Etest.

Conclusions

Clinicians and microbiologists should be aware of the possibility of the emergence of daptomycin non-susceptibility (or increase in minimal inhibitory concentration) during prolonged therapy and closely monitor the susceptibility of persisting isolates that might be recovered during therapy.

Infectious Complications in Atopic Dermatitis

Atopic dermatitis is characterized by the interplay of skin barrier defects with the immune system and skin microbiome that causes patients to be at risk for infectious complications. This article reviews the pathogenesis of atopic dermatitis and the mechanisms through which patients are at risk for infection from bacterial, viral, and fungal pathogens. Although these complications may be managed acutely, prevention of secondary infections depends on a multipronged approach in the maintenance of skin integrity, control of flares, and microbial pathogens.

Efficacy of bleach baths in reducing severity of atopic dermatitis: A systematic review and meta-analysis

BACKGROUND

Bleach baths have been proposed as a treatment for decreasing the severity of atopic dermatitis (AD). However, conflicting results have been found regarding their efficacy.

OBJECTIVE

To determine the efficacy of bleach vs water baths at decreasing AD severity.

METHODS

We performed a systematic review of all studies evaluating the efficacy of bleach baths for AD. Cochrane, EMBASE, GREAT, LILACS, MEDLINE, and Scopus were searched. Two authors independently performed study selection and data extraction.

RESULTS

Five studies were included in the review. Four studies reported significantly decreased AD severity in patients treated with bleach on at least 1 time point. However, of 4 studies comparing bleach with water baths, only 2 found significantly greater decreases in AD severity with bleach baths, 1 found greater decreases with water baths, and 1 found no significant differences. In pooled analyses, there were no significant differences observed between bleach vs water baths at 4 weeks vs baseline for the Eczema Area and Severity Index (I² = 98%; random effect regression model, P = .16) or body surface area (I² = 96%; P = .36).

CONCLUSION

Although bleach baths are effective in decreasing AD severity, they do not appear to be more effective than water baths alone. Future larger-scale, well-designed randomized controlled trials are needed.

Decolonization of Staphylococcus aureus in patients with atopic dermatitis: a reason for increasing resistance to antibiotics?

INTRODUCTION

Exacerbation of atopic dermatitis can be associated with bacterial infection. The skin of patients is colonized with Staphylococcus aureus in 90% of cases. An attempt has been made to demonstrate that eradication significantly reduces the severity of the disease. Studies indicate the efficacy of topical antibiotics, topical corticosteroids and calcineurin inhibitors. Due to increasing resistance to drugs and the defective antimicrobial peptide profile, decolonization is virtually impossible.

AIM

To determine the prevalence of S. aureus colonization among patients with atopic dermatitis and to assess antimicrobial susceptibility of isolated strains to antibiotics, especially fusidic acid and mupirocin.

MATERIAL AND METHODS

One hundred patients with atopic dermatitis and 50 healthy subjects were microbiologically assessed for the carriage of S. aureus. Antimicrobial susceptibility tests were performed using the broth-microdilution method for antibiotics: ampicillin, ciprofloxacin, daptomycin, erythromycin, fusidic acid, linezolid, lincomycin, mupirocin, tetracycline and vancomycin.

RESULTS

Staphylococcus aureus strains were isolated from the majority of our patients, either from the skin (71%) or the anterior nares (67%). In the present study, 10% of isolations represented methicillin-resistant S. aureus (MRSA). Antibiotics exhibited diverse activities against clinical isolates of S. aureus. Among those tested, the highest rates of resistance were shown for ampicillin - 58.5%, lincomycin - 37.5% and erythromycin - 31.0%. Enhanced resistance levels were expressed to mupirocin (17.5%) and fusidic acid (15.5%).

CONCLUSIONS

According to the increasing rate of resistance and quick recolonization after discontinuation of the treatment, chronic use of topical antibiotics is not recommended and should be limited to exacerbation of atopic dermatitis with clinical signs of bacterial infection.

Non-Prescription Treatment Options

The pathogenesis of atopic dermatitis (AD) is complex and multifactorial. However, recent advancements in the genetics and pathophysiology of AD suggest that epidermal barrier dysfunction is paramount in the development and progression of the condition (Boguniewicz and Leung, Immunol Rev 242(1):233-246, 2011). In addition to standard therapy for AD, there are a plethora of non-prescription treatment modalities which may be employed. Over-the-counter treatments for atopic dermatitis can come in the form of topical corticosteroids, moisturizers/emollients, and oral anti-histamines. Though these treatments are beneficial, prescription treatments may be quicker acting and more efficacious in patients with moderate to severe disease or during flares. OTC agents are best used for maintenance between flares and to prevent progression of mild disease. Alternative and complementary treatments lack strong efficacy evidence. However, wet wraps, bleach baths, and other treatments appear to be promising when used in conjunction with conventional treatments. With the financial burden of atopic dermatitis ranging from 364 million to 3.8 billion dollars each year in the United States, we suspect this topic will gain further research attention.

Evolving Concepts in Atopic Dermatitis

PURPOSE OF REVIEW

Tremendous advances have been made in the field of atopic dermatitis in the past 5 years. We will explore developments in burden of disease, co-morbidities, pathogenesis, prevention, and management.

RECENT FINDINGS

The tremendous burden moderate to severe atopic dermatitis (AD) places on families from a medical, psychosocial, and financial perspective has been characterized. Epidemiologic studies have identified intriguing new associations beyond the well-characterized "atopic march" of food allergies, asthma, and hay fever. Studies of primary prevention have gained traction including the remarkable impacts of early emollient therapy. Basic advances have simultaneously elucidated the nature of atopic inflammation, setting the stage for an explosion of new potential therapeutic targets. After a fallow period of nearly 15 years without a substantial therapeutic advance, this year has already seen two new FDA-approved treatments for AD. AD has a tremendous impact on quality of life with an underappreciated burden of disease; there are important newly described co-morbidities including ADHD and anemia; new insights into etio-pathogenesis have paved the way for novel topical therapies like crisaborole, and new systemic interventions like dupilumab.

Therapeutic Benefits of Natural Ingredients for Atopic Dermatitis

Although a variety of regimens are available for the treatment of atopic dermatitis (AD), severe adverse reactions and unpopular costs often limit their usage. In contrast, certain inexpensive, naturally-occurring ingredients are proven effective for AD with fewer side effects. The beneficial effects of these ingredients can be attributed to inhibition of cytokine and chemokine expression, IgE production, inflammatory cell infiltration, histamine release, and/or the enhancement of epidermal permeability barrier function. Since herbal medicines are widely available, inexpensive and generally safe, they could be valuable alternatives for the treatment of AD, particularly for those patients who are not suitable for the utilization of immune modulators. In this review, we summarize the therapeutic benefits of natural ingredients for the treatment of AD and the mechanisms of their actions.

Skin Colonization by Staphylococcus aureus Precedes the Clinical Diagnosis of Atopic Dermatitis in Infancy

Atopic dermatitis (AD) has a well-established association with skin colonization or infection by Staphylococcus aureus, which can exacerbate the disease. However, a causal relationship between specific changes in skin colonization during the first years of life and AD development still remains unclear. In this prospective birth cohort study, we aimed to characterize the association between skin colonization and AD development in 149 white infants with or without a family history of atopy. We assessed infants clinically and collected axillary and antecubital fossa skin swabs for culture-based analysis at birth and at seven time points over the first 2 years of life. We found that at age 3 months, S. aureus was more prevalent on the skin of infants who developed AD later on. S. aureus prevalence was increased on infants' skin at the time of AD onset and also 2 months before it, when compared with age-matched, unaffected infants. Furthermore, at AD onset, infants testing positive for S. aureus were younger than uncolonized subjects. In conclusion, our results suggest that specific changes in early-life skin colonization may actively contribute to clinical AD onset in infancy.

Atopic Dermatitis: Early Treatment in Children

Therapeutic regimens for the treatment and long-term management of AD traditionally had a two-fold objective of decreasing skin inflammation and repairing the defective skin barrier. Essential treatments for AD in children should include topical moisturizers for skin hydration and prevention of flares, topical anti-inflammatory medications (e.g. corticosteroids, calcineurin inhibitors, PDE4 inhibitor), allergen/irritant avoidance, and treatment of skin infections. Treatment regimens should be severity-based, and implemented in a stepwise approach tailored to the individual patient. This stepwise approach includes initial use of emollients, gentle skin care, and escalating to more potent anti-inflammatory treatments as the disease severity increases. Currently available systemic medications should be reserved for the presence of recalcitrance to topical therapies due to associated toxicities. We believe that early treatment of AD is not only essential in treating the skin disease, but also in preventing the development of additional atopic diseases, such as food allergy, asthma and allergic rhinitis. The defective skin barrier of AD permits a route of entry for food and environmental allergens, and upon exposure, keratinocytes secrete TSLP, which activates the T_H2 pathway. This T_H2 differentiation sets off the atopic march and the subsequent diseases that are seen. This review highlights treatment options and strategies in pediatric AD therapy with an emphasis on early therapy. Supporting evidence on the efficacy and safety of each intervention will be discussed.