Secondary infections in patients with atopic dermatitis

Hydrogel-Based Treatment of House Dust Mite-Induced Atopic Dermatitis through Triple Cleaning of Mites, Bacteria, and ROS-Related Inflammation

Atopic dermatitis (AD) is a chronic and recurrent inflammatory disease caused by abnormalities in skin immunoregulation. House dust mite can directly damage the skin barrier and thus sensitize the skin, which is one of the main allergens inducing AD in humans and widely exists in daily life. Meanwhile, the accompanying bacterial infections and exposure to additional allergens exacerbate the condition by generating excessive reactive oxygen species (ROS). Herein, we have developed the CPDP hydrogel with injectable and self-healing ability to combat pathogenic microorganisms and inflammatory environments for AD therapy. In vitro experiments have affirmed the efficacy of the CPDP hydrogel in combating mites, killing bacteria, and scavenging ROS. In a mouse model closely mimicking HDM-induced AD, the CPDP hydrogel has shown superior therapeutic effects, including reducing epidermal thickness and mast cell count, increasing collagen deposition, as well as down-regulating pro-inflammatory factors.

Atopic Dermatitis Disease Complications

This chapter will describe infectious complications of atopic dermatitis, including bacterial, viral, and fungal infections and the evolving understanding of the relationship between atopic dermatitis and infectious disease. The underlying immunological dysregulation and poor skin barrier function associated with atopic dermatitis not only increase the likelihood of infectious complications but also lend atopic dermatitis skin vulnerable to flares induced by environmental triggers. Thus, this chapter will also highlight the impact of common external environmental agents on precipitating flares of disease. Lastly, this chapter will discuss complications that can arise from treatments and the association of atopic dermatitis with more serious conditions such as lymphoma.

The Impact of Air Pollution on Atopic Dermatitis

PURPOSE OF REVIEW

Atopic dermatitis (AD) remains a dermatological disease that imposes a significant burden on society. Air pollution has previously been linked to both the onset and severity of atopic dermatitis. As air pollution remains a critical environmental factor impacting human health, this review seeks to provide an overview of the relationship between different air pollutants and AD.

RECENT FINDINGS

AD can develop from multiple causes that can be broadly grouped into epidermal barrier dysfunction and immune dysregulation. Air pollution imposes significant health risks and includes a wide variety of pollutant types. AD has been linked to outdoor air pollutants such as particulate matter (PM), volatile organic compounds (VOC), gaseous compounds, and heavy metals. Exposure to indoor pollutants such as tobacco smoke and fungal molds has also been associated with an increased incidence of AD. While different pollutants impact distinct molecular pathways in the cell, they mostly converge on ROS product, DNA damage, and dysregulated T-cell activity and cytokine production. The presented review suggests a strengthening tie between air pollution and AD. It points to opportunities for further studies to clarify, as well as potential therapeutic opportunities that leverage the mechanistic relationships between air pollution and AD.

Atopic dermatitis in a chimpanzee (pan troglodytes verus)-A diagnostic and therapeutic challenge

Diagnosis and treatment of atopic dermatitis (AD) in chimpanzees are challenging. Validated allergy tests specific for chimpanzees are not available. A multifactorial management of atopic dermatitis is important. Successful management of AD has, to the best knowledge of the authors, not been described in chimpanzees.

Zn-MOF hydrogel: regulation of ROS-mediated inflammatory microenvironment for treatment of atopic dermatitis

Atopic dermatitis (AD) is a chronic and recurrent inflammation disease associated with immune dysfunction. The high level of reactive oxygen species (ROS) causes high oxidative stress and further results in the deterioration of AD. At the same time, the ROS produced by bacterial infection can further aggravate AD. Here, the prepared PVA-based hydrogel (Gel) has a high ROS scavenging ability, and the antibacterial agent Zn-MOF(ZIF-8) loaded into the hydrogel shows a lasting and effective antibacterial activity. Thus, a Zn-MOF hydrogel (Gel@ZIF-8) is prepared to regulate ROS-mediated inflammatory microenvironment. In vitro experiments show that Gel@ZIF-8 has good antibacterial effect and cell biocompatibility. In the AD-induced mouse model, Gel@ZIF-8 can significantly enhance the therapeutic effect, such as reduce the thickness of epidermis, the number of mast cells and IgE antibodies. The results indicate that the ROS-scavenging hydrogel could treat the AD by regulating the inflammatory microenvironment, providing a promising treatment for managing AD.

Therapeutic Hydrogel Patch to Treat Atopic Dermatitis by Regulating Oxidative Stress

Atopic dermatitis (AD) is a chronic inflammatory disease associated with unbalanced immune responses in skin tissue. Although steroid drugs and antihistamines are generally used to treat AD, continuous administration causes multiple side effects. High oxidative stress derived from reactive oxygen species (ROS) has been implicated in the pathogenesis of AD. A high level of ROS promotes the release of pro-inflammatory cytokines and T-cell differentiation, resulting in the onset and deterioration of AD. Here, we report a therapeutic hydrogel patch suppressing the high oxidative stress generated in AD lesions. The hydrogel embedded with ROS-scavenging ceria nanoparticles leads to the decrease of both extracellular and intracellular ROS and exhibits cytoprotective effects in a highly oxidative condition. AD-induced mouse model studies show enhanced therapeutic outcomes, including a decrease in the epidermal thickness and levels of AD-associated immunological biomarkers. These findings indicate that a ROS-scavenging hydrogel could be a promising therapeutic hydrogel patch for treating and managing AD.

Brief Academic Review and Clinical Practice Guidelines for Pediatric Atopic Dermatitis

In this clinical guidelines article, we first include a brief review of the epidemiology, pathogenesis, clinical diagnoses, and scoring-scales for pediatric atopic dermatitis (AD). We then offer a set of pharmacologic treatment guidelines for infants and toddlers (<2 years), children (2-12 years), and adolescents (>12 years). We recommend irritant avoidance and liberal emollient usage as the cornerstone of treatment in all age-groups. In infants <2 years, we recommend topical corticosteroids as first-line medication-based therapy. In infants as young as 3 months, pimecrolimus, a topical calcineurin inhibitor, may also be used. As a last resort in patients <2 years, non-traditional therapies, such as the Aron regime, may be a safer option for refractory or resistant AD before off- label medications are considered. In children and adolescents >2 years, topical corticosteroids are still considered first-line therapies, but there is sufficient safety data to utilize topical calcineurin inhibitors and topical PDE4 inhibitors as well. In children ages 2-12 years whose atopic dermatitis fails to respond to prior treatments, oral systemic immunosuppressants can be used. For adolescents >12, the biologic, dupilumab, is an additional therapeutic option. A trial of phototherapy may also be utilized in children, particularly in adolescents >12 years, if they have access to treatment. Although not currently approved for the treatment of AD, Janus-kinase (JAK) inhibitors represent a promising new class of biologics with recently completed phase III clinical trials (JADE-- MONO1/2).

Anti-inflammatory effects of natural flavonoid diosmetin in IL-4 and LPS-induced macrophage activation and atopic dermatitis model

Diosmetin, a citrus flavonoid, has a variety of therapeutic properties such as antibacterial, anti-inflammatory and antioxidant effects. However, the effect of diosmetin on atopic dermatitis (AD) development has not been reported. This study thus aims to investigate whether diosmetin possesses inhibitory effects on AD development. A dinitrochlorobenzene (DNCB)-induced AD mouse model was used to evaluate the effects of diosmetin on AD development. Treatment with diosmetin significantly reduced the dermatitis score, thickness of epidermis and dermis and number of mast cells in comparison with the untreated group. Furthermore, immunohistochemical analysis using an anti-F4/80 antibody demonstrated that diosmetin significantly suppressed macrophage infiltration into the AD lesion. It was observed that the levels of pro-inflammatory cytokines (TNF-α, IL-4 and IL-1β) in skin lesion decreased in response to treatment with diosmetin. In addition, the anti-inflammatory effect of diosmetin was evaluated in LPS- or IL-4-induced a mouse macrophage cell line (raw 264.7). Diosmetin inhibited the production of nitric oxide and decreased the expression of inducible nitric oxide synthase (iNOS). Diosmetin not only suppressed the phosphorylation of MAP kinase (ERK 1/2, p38 and JNK) but the activation of JAK/STAT signaling. The mRNA analysis demonstrated that diosmetin also reduced the level of inflammatory cytokines such as IL-1β and IL-6. Collectively, these results demonstrate that diosmetin exhibits the inhibitory effect on AD, suggesting that diosmetin may be a potential therapeutic agent for this atopic disorder.

Skin - a vast organ with immunological function (Review)

The skin is an organ with multiple functions, where important inflammatory and immunological processes take place. The integrity of the skin barrier is necessary for it to fulfill its roles. An intact skin barrier requires a physiological keratinization process, but also a normal cutaneous microbial flora. Any change in the proliferation and differentiation of keratinocytes entails the disruption of the skin barrier and the triggering of inflammatory and immunological processes at this level, in response to the aggression of external pathogens. Also, there are several specialised immune cells in the skin (Langerhans cells, T regulator cells, T helper cells), that maintain a balance between pro-inflammatory and anti-inflammatory processes at this level. Disturbing the immune homeostasis causes inflammation and allergic skin reaction. Psoriasis and atopic dermatitis are two inflammatory diseases of the skin, characterized by perturbation of the mechanisms of skin barrier formation. The immune system of the skin is also involved in the pathophysiology of vitiligo and pemphigus. The aim of this review is to offer a brief presentation of the inflammatory and immunological processes that occur in the skin.

The role of bacterial skin infections in atopic dermatitis: expert statement and review from the International Eczema Council Skin Infection Group

Patients with atopic dermatitis (AD) have an increased risk of bacterial skin infections, which cause significant morbidity and, if untreated, may become systemic. Staphylococcus aureus colonizes the skin of most patients with AD and is the most common organism to cause infections. Overt bacterial infection is easily recognized by the appearance of weeping lesions, honey‐coloured crusts and pustules. However, the wide variability in clinical presentation of bacterial infection in AD and the inherent features of AD – cutaneous erythema and warmth, oozing associated with oedema, and regional lymphadenopathy – overlap with those of infection, making clinical diagnosis challenging. Furthermore, some features may be masked because of anatomical site‐ and skin‐type‐specific features, and the high frequency of S. aureus colonization in AD makes positive skin swab culture of suspected infection unreliable as a diagnostic tool. The host mechanisms and microbial virulence factors that underlie S. aureus colonization and infection in AD are incompletely understood. The aim of this article is to present the latest evidence from animal and human studies, including recent microbiome research, to define the clinical features of bacterial infections in AD, and to summarize our current understanding of the host and bacterial factors that influence microbial colonization and virulence.

Estimation of Health Utilities Based on the Response to Treatment in Atopic Dermatitis: a Population-based Study

PURPOSE

This study estimated utility weights based on the response to treatment for atopic dermatitis in the general population.

METHODS

The Korean general population aged 20-60 years was stratified by using a random sampling method based on age and sex. Two hypothetical health states of atopic dermatitis were developed: response to treatment and no response to treatment. Health utility values were estimated by using time trade-off (TTO) based on a period of 10 years, TTO based on life expectancy, and EuroQol 5-Dimension (EQ-5D) including a visual analog scale (VAS). The mean utility value and 95% CI were derived, and comparisons of subgroups using the t test and ANOVA were performed. We conducted a multilevel analysis after controlling the sociodemographic variables to consider repeated measures.

FINDINGS

A total of 155 participants were included in the survey. Their mean age was 39.7 years; 58.7% of participants were women. The mean health utility values for response and no response using TTO based on 10 years were 0.847 and 0.380, respectively. The estimated health utility values of response and no response were 0.865 and 0.476 using TTO based on life expectancy, and 0.814 and 0.279 using EQ-5D. For VAS, the response and no response were 0.744 and 0.322. After controlling the covariates, the important factors that affected utility values were response and no response to treatment (P < 0.001).

IMPLICATIONS

This study showed that the utility weights of people with no response to atopic dermatitis treatment were lower compared with response from the general population. Health care providers should therefore consider symptom control as an important factor affecting the quality of life of those with atopic dermatitis.

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.

Skin diseases associated with atopic dermatitis

Atopic dermatitis is a common chronic pruritic inflammatory skin disorder, characterized by an abnormal skin barrier, immune dysfunction, and an altered skin microbiome. Atopic dermatitis may be seen in conjunction with a variety of other skin disorders due to the complex pathogenesis of atopic dermatitis, involving genetic and environmental factors that are associated with immune dysfunction, barrier defects, and altered skin microbiomes. Skin disorders associated with atopic dermatitis include diseases sharing similar genetic origins like ichthyosis vulgaris, infectious diseases such as impetigo, and eczema herpeticum, in addition to the cutaneous autoimmune diseases, alopecia areata, and vitiligo. Atopic dermatitis is also often linked to such benign conditions as pityriasis alba and keratosis pilaris. This review discusses the cutaneous comorbidities of atopic dermatitis and their relationship via their occurrence in conjunction with atopic dermatitis.

An Unanticipated Complication of Atopic Dermatitis

An infant with a history of atopic dermatitis presented to the emergency department on 5 occasions with flulike symptoms. Eventually, this child presented with signs of infection and increased intracranial pressure: fever, bulging anterior fontanel, and leukocytosis. A computed tomography scan identified a large frontal lobe brain abscess. The abscess was surgically drained; culture was positive for Staphylococcus aureus. The initial source of the infected brain abscess was explored. Ultimately, it was thought to be secondary to impetiginized atopic dermatitis, an unusual but serious consequence of a common skin condition.

PRINCIPLES THERAPY OF ATOPIC DERMATITIS IN CHILDHOOD IN THE ASPECT OF MODERN CONCEPTS OF THE PATHOGENESIS OF THE DISEASE

The article contains data on the key links in the pathogenesis of atopic dermatitis in children. The authors of the article have covered modern approaches to topical therapy of atopic dermatitis in children. Modern algorithms of proactive therapy and control over the course of the disease are presented.

Commonality of the IL-4/IL-13 pathway in atopic diseases

INTRODUCTION

Allergy results from an aberrant Type 2 inflammatory response, triggered by a wide range of environmental antigens (allergens) that lead to various immune responses, culminating in the production of immunoglobulin E (IgE). Two key cytokines, interleukin (IL)-4 and IL-13, are critical to the induction and perpetuation of the Type 2 response, and have been implicated in multiple atopic diseases. Area covered: This review summarizes recent milestone developments that have elucidated components of the pathogenesis of atopic diseases such as atopic dermatitis (AD), asthma, and chronic sinusitis with nasal polyposis (CSwNP). Expert commentary: Several therapeutic agents that selectively target potentiators of the Type 2 pathway have shown efficacy in one or more of these atopic diseases, but few agents have proven to be broadly applicable across all three atopic diseases. Dupilumab, a human monoclonal antibody that simultaneously inhibits signaling of IL-4 and IL-13, has demonstrated significant clinical efficacy in AD, asthma, and CSwNP. The fact that these diseases often occur as comorbidities and respond to the same therapy suggests that there is a common underlying pathogenic pathway, and that IL-4 and IL-13 cytokines are central to regulating the pathogenesis of these atopic diseases.

Atopic Dermatitis Disease Complications

This chapter will describe infectious complications of atopic dermatitis, including bacterial, viral, and fungal infections and the evolving understanding of the relationship between atopic dermatitis and infectious disease. The underlying immunological dysregulation and poor skin barrier function associated with atopic dermatitis not only increases the likelihood of infectious complications, but also lends atopic dermatitis skin vulnerable to flares induced by environmental triggers. Thus, this chapter will also highlight the impact of common external environmental agents on precipitating flares of disease. Lastly, this chapter will discuss complications that can arise from treatments and the association of atopic dermatitis with more serious conditions such as lymphoma.

The Role of Staphylococcus aureus in Secondary Infections in Patients with Atopic Dermatitis (AD)

Staphylococcus aureus colonizes the mucous membrane of the nasal vestibule of a significant number of healthy people. These microorganisms are opportunistic pathogens, that in favorable conditions, may cause infections of various course, location or manifestation. Secondary infections emerge in cases when other risk factors contribute to such a change. One of the diseases during which S. aureus changes its saprophytic character to a pathogenic one is atopic dermatitis (AD), an allergic skin condition of a chronic and recurrent nature. Patients with AD are highly predisposed to secondary staphylococcal infections due to active S. aureus colonization of the stratum corneum, damage of the skin barrier or a defective immune response. Microorganisms present in skin lesions destroy the tissue by secreting enzymes and toxins, and additionally stimulate secondary allergic reactions. The toxins secreted by strains of S. aureus also act as superantigens and penetrate the skin barrier contributing to a chronic inflammation of the atopic skin lesions. The S. aureus species also releases proinflammatory proteins, including enzymes that cause tissue damage. When initiating treatment it is particularly important to properly assess that the onset of the secondary bacterial infection is caused by S. aureus and thus justifying the inclusion of antibiotic therapy. Depending on the severity and extent of the staphylococcal infection, topical antibiotics are used, usually mupirocin or fusidic acid, or general antibiotic treatment is introduced. Another therapeutic strategy without antibiotics has given a positive effect in patients.

Whole metagenome profiling reveals skin microbiome-dependent susceptibility to atopic dermatitis flare

Whole metagenome analysis has the potential to reveal functional triggers of skin diseases, but issues of cost, robustness and sampling efficacy have limited its application. Here, we have established an alternative, clinically practical and robust metagenomic analysis protocol and applied it to 80 skin microbiome samples epidemiologically stratified for atopic dermatitis (AD). We have identified distinct non-flare, baseline skin microbiome signatures enriched for Streptococcus and Gemella but depleted for Dermacoccus in AD-prone versus normal healthy skin. Bacterial challenge assays using keratinocytes and monocyte-derived dendritic cells established distinct IL-1-mediated, innate and Th1-mediated adaptive immune responses with Staphylococcus aureus and Staphylococcus epidermidis. Bacterial differences were complemented by perturbations in the eukaryotic community and functional shifts in the microbiome-wide gene repertoire, which could exacerbate a dry and alkaline phenotype primed for pathogen growth and inflammation in AD-susceptible skin. These findings provide insights into how the skin microbial community, skin surface microenvironment and immune system cross-modulate each other, escalating the destructive feedback cycle between them that leads to AD flare.

A Comprehensive Review of the Treatment of Atopic Eczema

Atopic eczema (AE) is a chronic, inflammatory skin disorder which usually develops in early childhood. In spite of intensive investigations, the causes of AE remain unclear, but are likely to be multifactorial in nature. Environmental factors or genetic-environmental interactions seem to play a key role in disease progression. Among various measures of AE managment, cutaneous hydration, which improves barrier function and relieve itchiness, may be helpful to reduce the need for topical steroid use and therefore should be used as a basic treatment. Avoiding aggravating factors is also a basic treatment of AE. Standard medical treatment with a pharmacologic approach may be necessary if basic treatment fails to control symptoms satisfactorily. Recently, more attention is given to a proactive therapeutic by regular intermittent application of low potency steroids or topical calcineurin inhibitors to prevent new flares. Furthermore, various targeted biologics are being introduced for AE control and are proposed as promising therapies. This paper provides a summary of the recent literature on the manangement of AE and a treatment guideline.

Consensus Guidelines for the Treatment of Atopic Dermatitis in Korea (Part II): Systemic Treatment

BACKGROUND

Since the treatment guidelines for atopic dermatitis (AD) were issued by the Korean Atopic Dermatitis Association (KADA) work group in 2006, there have been further advances in the systemic treatment of AD.

OBJECTIVE

We aimed to establish updated evidence- and experience-based systemic treatment guidelines for Korean AD.

METHODS

We compiled a database of references from relevant systematic reviews and guidelines regarding the systemic management of AD, including antihistamines, antimicrobials, systemic immunomodulators, allergen-specific immunotherapy, phototherapy, adjunctive treatment, and complementary and alternative medicines. Evidence for each statement was graded and classified based on the strength of the recommendation. Thirty-nine council members of KADA participated in the three rounds of votes and expert consensus recommendations were established.

RESULTS

The use of antihistamines is recommended to relieve pruritus and to prevent exacerbation due to scratching in AD patients. Infection should be controlled as needed and long-term medication should be avoided. For moderate to severe AD patients, concomitant active treatments with systemic immunomodulators are indicated. Cyclosporine is the first choice among systemic immunomodulators and others should be considered as second-line alternatives. Allergen-specific immunotherapy could be effective in AD patients with aeroallergen hypersensitivity. Phototherapy can be useful for moderate to severe AD patients and narrow-band ultraviolet B is the most effective option. Complementary and alternative medicines cannot be recommended for treating AD.

CONCLUSION

We expect these recommendations to be a reference guide for physicians and AD patients in choosing the appropriate treatment to improve quality of life and decrease unnecessary social medical costs.

Pimecrolimus in atopic dermatitis: consensus on safety and the need to allow use in infants

Atopic dermatitis (AD) is a distressing dermatological disease, which is highly prevalent during infancy, can persist into later life and requires long-term management with anti-inflammatory compounds. The introduction of the topical calcineurin inhibitors (TCIs), tacrolimus and pimecrolimus, more than 10 yr ago was a major breakthrough for the topical anti-inflammatory treatment of AD. Pimecrolimus 1% is approved for second-line use in children (≥2 yr old) and adults with mild-to-moderate AD. The age restriction was emphasized in a boxed warning added by the FDA in January 2006, which also highlights the lack of long-term safety data and the theoretical risk of skin malignancy and lymphoma. Since then, pimecrolimus has been extensively investigated in short- and long-term studies including over 4000 infants (<2 yr old). These studies showed that pimecrolimus effectively treats AD in infants, with sustained improvement with long-term intermittent use. Unlike topical corticosteroids, long-term TCI use does not carry the risks of skin atrophy, impaired epidermal barrier function or enhanced percutaneous absorption, and so is suitable for AD treatment especially in sensitive skin areas. Most importantly, the studies of pimecrolimus in infants provided no evidence for systemic immunosuppression, and a comprehensive body of evidence from clinical studies, post-marketing surveillance and epidemiological investigations does not support potential safety concerns. In conclusion, the authors consider that the labelling restrictions regarding the use of pimecrolimus in infants are no longer justified and recommend that the validity of the boxed warning for TCIs should be reconsidered.

Clinical pearls from atopic dermatitis and its infectious complications

Atopic dermatitis (AD) is clinically very heterogeneous and these differences can cause confusion. Differential diagnosis is also complicated by co-infections, particularly in infancy and early childhood. This paper describes the stages and differential diagnosis during the various stages of childhood. The authors also provide advice on how to distinguish between AD and other disorders together with guidance on tackling common issues with treatment such as steroid phobia.

Difficult to control atopic dermatitis

Difficult to control atopic dermatitis (AD) presents a therapeutic challenge and often requires combinations of topical and systemic treatment. Anti-inflammatory treatment of severe AD most commonly includes topical glucocorticosteroids and topical calcineurin antagonists used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, the topical calcineurin inhibitors tacrolimus and pimecrolimus are preferred in certain locations. Systemic anti-inflammatory treatment is an option for severe refractory cases. Microbial colonization and superinfection contribute to disease exacerbation and thus justify additional antimicrobial / antiseptic treatment. Systemic antihistamines (H1) may relieve pruritus but do not have sufficient effect on eczema. Adjuvant therapy includes UV irradiation preferably of UVA1 wavelength. “Eczema school” educational programs have been proven to be helpful.

An unusual presentation of herpes simplex virus type 1 infection in a child

We describe an 11-year-old girl presenting with lichen simplex chronicus (LSC) and acute bilateral carpal tunnel syndrome (CTS) following herpes simplex virus type 1 (HSV-1) infection as evidenced by serological data and by detection of HSV-1 DNA in the blood with the use of PCR. Based on the literature search, this case represents the first childhood case of LSC and acute bilateral CTS following HSV-1 infection. The experience with this patient emphasizes the importance of serological tests and PCR as well as the other laboratory techniques for the accurate diagnosis and management of the disease.

Guidelines for treatment of atopic eczema (atopic dermatitis) part I

The existing evidence for treatment of atopic eczema (atopic dermatitis, AE) is evaluated using the national standard Appraisal of Guidelines Research and Evaluation. The consensus process consisted of a nominal group process and a DELPHI procedure. Management of AE must consider the individual symptomatic variability of the disease. Basic therapy is focused on hydrating topical treatment, and avoidance of specific and unspecific provocation factors. Anti-inflammatory treatment based on topical glucocorticosteroids and topical calcineurin inhibitors (TCI) is used for exacerbation management and more recently for proactive therapy in selected cases. Topical corticosteroids remain the mainstay of therapy, but the TCI tacrolimus and pimecrolimus are preferred in certain locations. Systemic immune-suppressive treatment is an option for severe refractory cases. Microbial colonization and superinfection may induce disease exacerbation and can justify additional antimicrobial treatment. Adjuvant therapy includes UV irradiation preferably with UVA1 wavelength or UVB 311 nm. Dietary recommendations should be specific and given only in diagnosed individual food allergy. Allergen-specific immunotherapy to aeroallergens may be useful in selected cases. Stress-induced exacerbations may make psychosomatic counselling recommendable. 'Eczema school' educational programs have been proven to be helpful. Pruritus is targeted with the majority of the recommended therapies, but some patients need additional antipruritic therapies.

The melanocortin 1 receptor (MC1R) inhibits the inflammatory response in Raw 264.7 cells and atopic dermatitis (AD) mouse model

The alpha melanocyte stimulating hormone receptor (MC1R) is one of five G-protein coupled receptors belonging to the melanocortin subfamily, MC1R gene has been known to play a major role in regulating of fur color in mammals, and α-MSH and ACTH are endogenous nonselective agonists for MC1R. However, we found that MC1R was highly expressed in Raw 264.7 cells which were important inflammatory cells involved in the initiation of inflammatory responses. In addition, Cyclic AMP is not only a key molecule in the MC1R signal transduction pathway, but dampen innate immune-mediated responses. These intriguing biological results triggered the further conformation studies; it suggested that MC1R was very likely to be an important role in immunoregulation. In this study, we were to investigate the immunosuppressive effects of MC1R on inflammation in lipopolysaccharide (LPS) stimulated Raw 264.7 cells and LPS induced vivo 2-chloro-1,3,5-trinitrobenzene (TNCB)-induced atopic dermatitis (AD) model. The effects of the MC1R antagonist psoralen on pro-inflammatory cytokines and signaling pathways were analyzed by enzyme-linked immunosorbent assay, western blot, real-time fluorescence quantitative PCR and Histological analysis. Our results show a consistent and marked effect of high concentrations of MC1R antagonist psoralen increased the level of MC1R mRNA in Raw 264.7 cells by cumulative feedback regulation through preferential binding of MC1R. Moreover, as evidenced by inhibiting the LPS-induced TNF-α, IL-6 and enhancing the expression level of cyclic AMP protein in vitro. In vivo study it was also observed that psoralen promoted on histopathologic changes in the skin tissue of TNCB-induced AD mice. Taken together, our results suggest that MC1R decrease the inflammation in vitro and vivo, and might be a therapeutic signaling pathway to against inflammatory diseases.

Response to infections in patients with asthma and atopic disease: an epiphenomenon or reflection of host susceptibility?

Associations between respiratory tract infections and asthma inception and exacerbations are well established. Infant respiratory syncytial virus and rhinovirus infections are known to be associated with an increased risk of asthma development, and among children with prevalent asthma, 85% of asthma exacerbations are associated with viral infections. However, the exact nature of this relationship remains unclear. Is the increase in severity of infections an epiphenomenon, meaning respiratory tract infections just appear to be more severe in patients with underlying respiratory disease, or instead a reflection of altered host susceptibility among persons with asthma and atopic disease? The main focus of this review is to summarize the available levels of evidence supporting or refuting the notion that patients with asthma or atopic disease have an altered susceptibility to selected pathogens, as well as discussing the biological mechanism or mechanisms that might explain such associations. Finally, we will outline areas in need of further research because understanding the relationships between infections and asthma has important implications for asthma prevention and treatment, including potential new pathways that might target the host immune response to select pathogens.

Management of itch in atopic dermatitis

Atopic dermatitis is a common, pruritic, inflammatory skin disorder. Chronic, localized, or even generalized pruritus is the diagnostic hallmark of atopic dermatitis, and its management remains a challenge for physicians. The threshold for itch and alloknesis is markedly reduced in these patients, and infections can promote exacerbation and thereby increase the itch. Modern management consists of anti-inflammatory, occasionally antiseptic, as well as antipruritic therapies to address the epidermal barrier as well as immunomodulation or infection. Mild forms of atopic dermatitis may be controlled with topical therapies, but moderate-to-severe forms often require a combination of systemic treatments consisting of antipruritic and immunosuppressive drugs, phototherapy, and topical compounds. In addition, patient education and a therapeutic regimen to help the patient cope with the itch and eczema are important adjuvant strategies for optimized long-term management. This review highlights various topical, systemic, and complementary and alternative therapies, as well as provide a therapeutic ladder for optimized long-term control of itch in atopic dermatitis.

Cutaneous yeast microflora in patients with atopic dermatitis

The skin of persons with atopic dermatitis (AD) is very susceptible to cutaneous infection, and some yeast species may also aggravate AD. The total yeast population of an AD patient’s skin and its relation with individual age and body part remains poorly characterized. The aim of this study was to clarify the differences in cutaneous yeast flora by age and body parts of AD patients.

By swabbing affected body parts (hands, legs, face, neck or trunk), 241 samples were collected from patients with AD (132 children and 109 adults), and as controls, 40 samples were taken from healthy individuals (20 children, 20 adults).

In all, 89 (36.9%) of samples were positive; the yeast isolated belonged to three genera: Candida (27.4%), Malassezia (6.6%), and Rhodotorula (2.9%). Cutaneous colonization with yeasts was two-fold higher in the adults than in children (P<0.0001). The distribution of the yeast species was dependent on the body part sampled: Malassezia predominated in the face, neck, and trunk regions (P=0.0047); Candida more frequently colonized hands and legs (P=0.0029).

Our study showed that cutaneous yeast flora and distribution of yeast species depends significantly on the age of the AD patient and the body part affected by atopic dermatitis.

Differential suppression of epidermal antimicrobial protein expression in atopic dermatitis and in EFAD mice by pimecrolimus compared to corticosteroids

It has been suggested that the increased rate of bacterial infection in atopic dermatitis (AD) may be caused by reduced antimicrobial protein (AMP) expression. We were interested whether common treatments in AD affect antimicrobial defense. We investigated the effects of topically applied corticosteroids betamethasone valerate (BV) and triamacinolone acetonide (TA) and those of the calcineurin inhibitor pimecrolimus for 3 weeks on AMP expression in AD. BV and TA treatment in AD led to a significant reduction in AMP expression; protein expression of human beta-defensins (hBD)-2 and hBD-3, psoriasin, RNase 7 and cathelicidin LL-37 was below the level in skin of healthy controls. After pimecrolimus treatment, AMP expression was also reduced but less compared to BV and TA; the expression levels of hBD-2, psoriasin and RNase 7 still remained above the control levels. In essential fatty acid-deficient (EFAD) mice, a model of chronic skin barrier disease with inflammation, expression of the mouse beta-defensins mBD-1, mBD-3 and mBD-14 (orthologues for hBD-1, hBD-2 and hBD-3, respectively), was reduced by both treatments, again more pronounced by BV compared to pimecrolimus. In summary, we found that treatment for AD with corticosteroids in human skin and EFAD mice caused a strong reduction in AMPs; reduction was less with pimecrolimus. This result may explain the clinical observation that prolonged treatment with topical corticosteroids sometimes leads to bacterial infection.

Smallpox vaccination and all-cause infectious disease hospitalization: a Danish register-based cohort study

BACKGROUND

There is growing evidence from observational studies and randomized trials in low-income countries that vaccinations have non-specific effects. Administration of live vaccines reduces overall child morbidity and mortality, presumably due to protection against non-targeted infections. In Denmark, the live vaccine against smallpox was phased out in the 1970s due to the eradication of smallpox. We used the phasing-out period to investigate the effect of smallpox vaccination on the risk of hospitalization for infections.

METHODS

From the Copenhagen School Health Records Register, a cohort of 4048 individuals was sampled, of whom 3559 had information about receiving or not receiving smallpox vaccination. Infectious disease hospitalizations were identified in the Danish National Patient Register.

RESULTS

During 87,228 person-years of follow-up, 1440 infectious disease hospitalizations occurred. Smallpox-vaccinated individuals had a reduced risk of all-cause infectious disease hospitalization compared with smallpox-unvaccinated individuals [hazard ratio (HR) 0.84; 95% confidence interval (CI) 0.72-0.98]. The reduced risk of hospitalizations was seen for most subgroups of infectious diseases. The effect may have been most pronounced after early smallpox vaccination (vaccination age <3.5 years: HR 0.81; 95% CI 0.69-0.95; vaccination age ≥ 3.5 years: HR 0.91 95% CI 0.76-1.10). Among the smallpox-vaccinated, the risk of infectious disease hospitalization increased 6% with each 1-year increase in vaccination age (HR 1.06; 95% CI 1.02-1.10).

CONCLUSION

Smallpox vaccination is associated with a reduced risk of infectious disease hospitalization in a high-income setting.

Immunoglobulin E antibody reactivity to bacterial antigens in atopic dermatitis patients

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease affecting up to 20% children and 9% adults world-wide. AD patients are often sensitized against a broad variety of allergens and more than 90% of them suffer from skin superinfections with Staphylococcus aureus.

OBJECTIVE

In this study, we searched for the presence of specific IgE antibodies against S. aureus and Escherichia coli antigens in AD patients.

METHODS

Sera from AD patients (n=79), patients suffering only from allergic rhinoconjunctivitis (n=41) or allergic asthma (n=37) were tested for IgE reactivity to nitrocellulose-blotted S. aureus, E. coli and gut bacterial antigens. IgE-reactive bacterial antigens were affinity purified and identified by mass spectrometry.

RESULTS

More than 30% of AD patients but not patients suffering only from allergic rhinoconjunctivitis and asthma or non-allergic persons exhibited IgE binding to several protein antigens among them DNA-binding and ribosomal proteins and flagellin. Patients with severe skin manifestations showed more frequently IgE reactivity to S. aureus compared with AD patients with mild symptoms. Positive immediate and late skin test reactions could be induced in sensitized AD patients with S. aureus extract.

CONCLUSION AND CLINICAL RELEVANCE

Specific IgE reactivities against a variety of bacterial antigens were observed in a subgroup comprising a third of AD patients and may contribute to allergic inflammation.

Mechanical and metabolic injury to the skin barrier leads to increased expression of murine β-defensin-1, -3, and -14

Protection of the skin against microbiological infection is provided by the permeability barrier and by antimicrobial proteins. We asked whether the expression of murine β-defensins (mBDs)-1, -3, and -14-orthologs of human β-defensins hBD-1, -2, and -3, respectively--is stimulated by mechanically/physicochemically (tape stripping or acetone treatment) or metabolically (essential fatty acid-deficient (EFAD) diet) induced skin barrier dysfunction. Both methods led to a moderate induction of mBD-1 and mBD-14 and a pronounced induction of mBD-3 mRNA. Protein expression of the mBDs was increased as shown by immunohistology and by western blotting. Artificial barrier repair by occlusion significantly reduced the increased expression of mBD-14 after mechanical injury and of all three mBDs in EFAD mice, supporting an interrelationship between permeability and the antimicrobial barrier. mBD-3 expression was stimulated in vitro by tumor necrosis factor-α (TNF-α), and a neutralizing anti-TNF-α antibody significantly reduced increased mBD-3 expression after barrier injury in mouse skin, indicating that induction of mBD-3 expression is mediated by cytokines. The expression of mBD-14 was stimulated by transforming growth factor-α and not by TNF-α. In summary, we demonstrated upregulation of mBD1, -3, and -14 after mechanically and metabolically induced skin barrier disruption, which may be an attempt to increase defense in the case of permeability barrier dysfunction.

The safety and efficacy of tacrolimus ointment in pediatric patients with atopic dermatitis

Atopic dermatitis (AD) is the most common skin disease in children, and its prevalence is increasing. It is a chronic disorder, characterized by intermittent flares and phases of remission. Treatment regimens often require multiple therapies. These can vary between patients, and in an individual patient, depending on the state of disease. The traditional treatment for AD flares is topical corticosteroids, which are fast acting and effective for relief of symptoms, but may cause adverse effects, including those resulting from systemic absorption, particularly in children. Topical calcineurin inhibitors (TCIs) are alternative treatments for AD. Tacrolimus ointment, a TCI, is approved for patients aged 2 years and older. Multiple studies have shown that tacrolimus is effective for short-term relief of symptoms in pediatric patients with AD. Long-term trials have demonstrated that the effectiveness of tacrolimus is maintained for up to 4 years in children. Additional studies have revealed that long-term intermittent use of tacrolimus as part of maintenance therapy can prevent AD flares. Tacrolimus has a low potential for systemic accumulation, and analysis of long-term studies indicates that it has a good safety profile. Treatment with tacrolimus, alone or in combination with topical corticosteroids for acute flares, may be a useful option for long-term management of AD in pediatric patients.

Staphylococcus aureus: An old pathogen with new weapons

Staphylococcus aureus has been recognized as an important human pathogen for more than 100 years. S aureus has been able to adapt and evolve in terms of its resistance traits and virulence factors; it is among the most important causes of human infections in the twenty-first century. Rapid molecular identification in the clinical microbiology laboratory of these resistance and virulence factors expressed by S aureus will play an important role in the future in decreasing the morbidity and mortality of infections. This article addresses the emerging aspects of infections caused by S aureus, including microbiology, epidemiology, clinical presentation, pathogenesis, diagnosis, treatment and prognosis, and immunity.

What's new in atopic eczema?

IMPORTANCE OF THE FIELD

Atopic eczema (AE) is a chronic relapsing inflammatory skin condition and one of the most common, potentially debilitating diseases with increasing incidence.

AREAS COVERED IN THIS REVIEW

The complex etiology of AE with multiple systemic and local immunologic and inflammatory responses and interactions between susceptibility genes and environmental factors leading to defects in skin barrier function and eczematous skin lesions is presented. Knowledge of pathogenesis is important for understanding the more innovative treatment approaches discussed.

WHAT THE READER WILL GAIN

Basic therapy consists of hydrating topical treatment and avoidance of specific and unspecific provocation factors. For acute eczematous skin lesions, anti-inflammatory treatment consists mainly of topical glucocorticoids and topical calcineurin inhibitors (tacrolimus and pimecrolimus). Microbial colonization and superinfection may induce skin exacerbation, which can be treated by either topical or systemic antimicrobial treatment. Systemic anti-inflammatory therapy is limited to severe cases and consists of systemic steroids, cyclosporine A or mycophenolate mofetil. Novel anti-inflammatory concepts that go beyond corticosteroids are in the early phases of development. There are targeted therapeutic approaches, such as cytokine and chemokine modulators and it remains to be investigated how effective they will be and what side effects they may carry.

TAKE HOME MESSAGE

Existing treatment modalities such as barrier repair therapy, topical immunosuppressive agents, antiseptic treatment as well as systemic treatment options are discussed. The review aims to summarize the most recent findings of more innovative treatment approaches such as modulation of cytokines or chemokines, modulation of T-cell responses or anti-IgE therapy.

Antibiotics for the allergist: part 2

OBJECTIVE

To review antibiotic use and selection for disorders commonly seen in allergy practice.

DATA SOURCES

MEDLINE searches were performed cross-referencing antibiotic, antimicrobial, management, and treatment with multiple disorders commonly seen in allergy practice. References of the chosen articles were also examined.

STUDY SELECTION

Articles were selected based on their relevance to the subject matter.

RESULTS

A large body of research is available relevant to both conventional and novel uses of antibiotics. The use of antibiotics is in question for some disorders, whereas novel approaches to therapy with macrolide antibiotics are areas of active investigation. Meanwhile, patterns of microbial resistance continue to evolve.

CONCLUSION

For decades, antibiotics have been traditional first-line treatment for many disorders. Currently, this paradigm appears to be shifting as periods of observation come into favor and nonbacterial causes of inflammation are under greater scrutiny. Nonetheless, appropriate antibiotic selection often remains a key element in the treatment of these disorders. Knowledge of the relevant microbiology is an inherent requirement in selecting antibiotic therapies and necessitates awareness of current trends in bacterial resistance.

Role of bacterial pathogens in atopic dermatitis

The skin of atopic dermatitis (AD) patients exhibits a striking susceptibility to colonization and infection with Staphylococcus aureus. This review summarizes our understanding about the role of S. aureus in AD. Indeed, S. aureus colonization is both a cause and a consequence of allergic skin inflammation. The mechanisms that allergic skin inflammation of AD promotes the increase of S. aureus colonization include skin barrier dysfunction, increased synthesis of the extracellular matrix adhesins for S. aureus, and defective innate immune responses due to decreased production of endogenous antimicrobial peptides. On the other hand, the exotoxins secreted by S. aureus are superantigens. Staphylococcal superantigens (SsAgs) may penetrate the skin barrier and contribute to the persistence and exacerbation of allergic skin inflammation in AD through the stimulation of massive T cells, the role of allergens, direct stimulation of antigen-presenting cells and keratinocytes, the expansion of skin-homing cutaneous lymphocyte-associated antigen-positive T cells, and the augmentation of allergen-induced skin inflammation. SsAgs also induce corticosteroid resistance. In therapeutic interventions, anti-inflammatory therapy alone is very effective in reducing S. aureus colonization on the skin, but antibiotic treatment alone is unable to improve the allergic skin inflammation of AD. Therefore, we recommend the combination therapy of anti-inflammatory drugs and antibiotics in the AD patients with secondary bacterial infection, exacerbated AD, or poorly controlled AD. However, when AD is well controlled by anti-inflammatory drugs alone, we do not recommend the antibiotic therapy.