Bacterial and Viral Infections in Atopic Dermatitis: a Comprehensive Review

Bioactive substance contents and therapeutic potential for skin inflammation of an herbal gel containing Derris reticulata and Glycyrrhiza glabra

CONTEXT

Derris reticulata Craib. and Glycyrrhiza glabra L., of the Fabaceae, have been used as active components in Thai herbal formulas for the treatment of fever and skin diseases.

OBJECTIVE

To evaluate the physicochemical and pharmacological properties of the developed herbal gel formulation containing the combined extract from D. reticulata stem wood and G. glabra root (RGF).

MATERIALS AND METHODS

The potential of the herbal gel formulation containing RGF (8% w/w) as the active ingredient was studied by evaluating the anti-inflammatory, antioxidant, and anti-Staphylococcus aureus activities using quantitative reverse transcription-polymerase chain reaction assay, spectrophotometric method, and broth microdilution technique, respectively. The reference standards for the biological testing included Nω-nitro-L-arginine (L-NA), ascorbic acid, catechin, and penicillin G. The stability study of the RGF herbal gel was performed by a heating-cooling test (at 45 °C for 24 h and at 4 °C for 24 h/1 cycle; for 6 cycles), and the bioactive marker compounds in the herbal gel were investigated by the HPLC technique.

RESULTS

RGF showed promising pharmacological effects, particularly on its anti-inflammatory property (IC50 73.86 µg/mL), compared to L-NA (IC50 47.10 µg/mL). The RGF-containing gel demonstrated anti-inflammatory (IC50 3.59 mg/mL) and free radical scavenging effects (IC50 0.05-4.39 mg/mL), whereas it had no anti-S. aureus activity (MIC > 10 mg/mL). The active ingredient in the developed herbal gel significantly inhibited lipopolysaccharide-induced nitric oxide production by downregulating iNOS mRNA levels. The contents of the bioactive markers in the RGF gel (lupinifolin and glabridin) did not change significantly after stability testing.

DISCUSSION AND CONCLUSIONS

The RGF-containing gel has potential to be further developed as an herbal product for the treatment of skin inflammation.

Patho-immunological mechanisms of atopic dermatitis: The role of the three major human microbiomes

Atopic dermatitis (AD) is a genetically predisposed allergic inflammatory dermatosis with chronic, pruritic, and recurrent features. Patients with AD have dry and itchy skin, often accompanied by chronic eczematous lesions, allergic rhinitis, or asthma, which has a considerable impact on their daily lives. With advances in genome sequencing technology, it has been demonstrated that microorganisms are involved in this disease, and the microorganisms associated with AD are attracting considerable research attention. An increasing number of studies conducted in recent years have demonstrated that an imbalanced microbiome in AD patients has substantial impact on disease prognosis, and the causes are closely tied to various immune mechanisms. However, the involvement of microorganisms in the pathogenesis of AD remains poorly understood. In this paper, we review the advances in research on the immunological mechanisms of the skin microbiome, intestinal microbiome, and lung microbiome that are related to AD prognosis and immunotherapy protocols. It is hoped that this approach will lay the foundation for exploring the pathogenesis of and emerging treatments for AD.

Isolation of the novel phage SAP71 and its potential use against Staphylococcus aureus in an atopic dermatitis mouse model

Atopic dermatitis (AD) is accompanied by changes in skin microbiota, in which abnormal colonization of Staphylococcus aureus is particularly common. The antibiotic treatment is prone to destroy the commensal bacterial community, further exacerbating the microbiome dysbiosis. Elimination of S. aureus through phage-targeted therapies presents a promising method in the treatment strategy of AD. In this study, we isolated a novel phage SAP71, which specifically lysed S. aureus. Genome sequencing showed that SAP71 contained no virulence, lysogenic, or antimicrobial resistance genes, making this lytic phage a potential agent for phage therapy. Moreover, we demonstrated that phage SAP71 was able to significantly improve the skin lesions, reduce the bacterial loads in the skin, and prevent the development of AD-like skin pathological changes in an AD model. In short, phage SAP71 was demonstrated to effectively treat S. aureus infection in AD, which provided a theoretical basis for the clinical phage therapy of AD.

Progressive accumulation of hyperinflammatory NKG2Dlow NK cells in early childhood severe atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that often precedes the development of food allergy, asthma, and allergic rhinitis. The prevailing paradigm holds that a reduced frequency and function of natural killer (NK) cell contributes to AD pathogenesis, yet the underlying mechanisms and contributions of NK cells to allergic comorbidities remain ill-defined. Here, analysis of circulating NK cells in a longitudinal early life cohort of children with AD revealed a progressive accumulation of NK cells with low expression of the activating receptor NKG2D, which was linked to more severe AD and sensitivity to allergens. This was most notable in children co-sensitized to food and aeroallergens, a risk factor for development of asthma. Individual-level longitudinal analysis in a subset of children revealed coincident reduction of NKG2D on NK cells with acquired or persistent sensitization, and this was associated with impaired skin barrier function assessed by transepidermal water loss. Low expression of NKG2D on NK cells was paradoxically associated with depressed cytolytic function but exaggerated release of the proinflammatory cytokine tumor necrosis factor-α. These observations provide important insights into a potential mechanism underlying the development of allergic comorbidity in early life in children with AD, which involves altered NK cell functional responses, and define an endotype of severe AD.

Hydrogels: a promising therapeutic platform for inflammatory skin diseases treatment

Inflammatory skin diseases, such as psoriasis and atopic dermatitis, pose significant health challenges due to their long-lasting nature, potential for serious complications, and significant health risks, which requires treatments that are both effective and exhibit minimal side effects. Hydrogels offer an innovative solution due to their biocompatibility, tunability, controlled drug delivery capabilities, enhanced treatment adherence and minimized side effects risk. This review explores the mechanisms that guide the design of hydrogel therapeutic platforms from multiple perspectives, focusing on the components of hydrogels, their adjustable physical and chemical properties, and their interactions with cells and drugs to underscore their clinical potential. We also examine various therapeutic agents for psoriasis and atopic dermatitis that can be integrated into hydrogels, including traditional drugs, novel compounds targeting oxidative stress, small molecule drugs, biologics, and emerging therapies, offering insights into their mechanisms and advantages. Additionally, we review clinical trial data to evaluate the effectiveness and safety of hydrogel-based treatments in managing psoriasis and atopic dermatitis under complex disease conditions. Lastly, we discuss the current challenges and future opportunities for hydrogel therapeutics in treating psoriasis and atopic dermatitis, such as improving skin barrier penetration and developing multifunctional hydrogels, and highlight emerging opportunities to enhance long-term safety and stability.

Parental Attitudes and Practices regarding Atopic Dermatitis: A Cross-Sectional Study among a Thai Population

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disorder common in children. Successful pediatric AD therapy requires parental assistance. Thus, evaluating parental knowledge, attitudes, and behaviors regarding childhood AD may lead to more educational recommendations to help children control AD in the future. This study examined parents' knowledge, attitudes, and conduct concerning AD in families with and without children with AD.

METHOD

The Pediatric Department, Faculty of Medicine, Khon Kaen University, Thailand, conducted a cross-sectional study from June to December 2023. Parents of children who visited the dermatology clinic with or without AD were asked to complete a Google form questionnaire.

RESULTS

A total of 372 parents answered a questionnaire about AD pathophysiology, knowledge, attitudes, and practices. The participants were 293 (78.8%) female participants and 79 (21.2%) male participants. The average age was 29.79 (SD 4.91). Most parents (319, 85.8%) did not work in the medical field, and more than half (228 instances, 61.29%) had children diagnosed with AD.

CONCLUSIONS

Parents of children with AD understood AD causes and triggers better than parents of children without AD. But, "exposure to furry toys" that may contain dust and allergies and "infection" that may cause AD flare-ups were the most common triggers, regardless of the group. Appropriate information should be supplied because both the parents of children with AD and those of children without AD reported immediate food avoidance without confirmatory testing, which might lead to malnutrition. Clinicians and families handling patients with AD require further education.

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.

Dupilumab Safety and Efficacy up to 1 Year in Children Aged 6 Months to 5 Years with Atopic Dermatitis: Results from a Phase 3 Open-Label Extension Study

BACKGROUND

Pediatric patients with moderate-to-severe atopic dermatitis (AD) often experience a high disease burden and have a high risk of persistent disease. Standard-of-care immunosuppressive systemic treatments have been used off-label for AD in pediatric patients despite concerns for suboptimal safety with continuous use and risk of relapse upon discontinuation. The biologic agent dupilumab is the first systemic treatment approved for moderate-to-severe AD in children as young as 6 months. Long-term safety and efficacy data in this patient population are needed to inform continuous AD management.

OBJECTIVES

The purpose of this work was to determine the long-term safety and efficacy of dupilumab treatment up to 1 year in an open-label extension (OLE) study [LIBERTY AD PED-OLE (NCT02612454)] in children aged 6 months to 5 years with moderate-to-severe AD who previously participated in the 16-week, double-blind, phase 3 LIBERTY AD PRESCHOOL trial (NCT03346434 part B; parent study) and were subsequently enrolled in PED-OLE.

METHODS

In PED-OLE, patients received dupilumab every 4 weeks according to a weight-tiered regimen (body weight ≥ 5 kg to < 15 kg: 200 mg; ≥ 15 kg to < 30 kg: 300 mg).

RESULTS

Data for 142 patients were analyzed, 60 of whom had completed the 52-week visit at time of database lock. Mean age at baseline was 4.1 y [SD, 1.13; range, 1.0-5.9 years]. A majority (78.2%) of patients reported ≥ 1 treatment-emergent adverse event (TEAE), most of which were mild or moderate and transient. The most frequently reported TEAEs were nasopharyngitis (19.7%), cough (15.5%), and pyrexia (14.1%). One TEAE led to treatment discontinuation (severe urticaria, which resolved in 1 day). By week 52, 36.2% of patients had achieved an Investigator's Global Assessment score of 0/1 (clear/almost clear skin), and 96.6%, 79.3%, and 58.6% had at least 50%, 75%, or 90% improvement, respectively, in Eczema Area and Severity Index scores.

CONCLUSIONS

Consistent with results seen in adults, adolescents, and older children (aged 6-11 years), treatment with dupilumab for up to 1 year in children aged 6 months to 5 years with inadequately controlled moderate-to-severe AD demonstrated an acceptable long-term safety profile and sustained efficacy. These results support the long-term continuous use of dupilumab in this patient population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02612454 and NCT03346434 (part B).

Atopic Dermatitis Complicated by Recurrent Eczema Herpeticum Is Characterized by Multiple, Concurrent Epidermal Inflammatory Endotypes

A subgroup of patients with atopic dermatitis (AD) suffers from recurrent, disseminated herpes simplex virus skin infection, termed eczema herpeticum. To determine the transcriptional mechanisms of the skin and immune system pathobiology that underlie development of AD with eczema herpeticum (ADEH), we performed RNA-sequencing analysis of nonlesional skin (epidermis, dermis) from AD patients with and without a history of ADEH (ADEH+, n = 15; ADEH-, n = 13) along with healthy controls (n = 15). We also performed RNA sequencing on participants' plasmacytoid dendritic cells infected in vitro with herpes simplex virus 1. ADEH+ patients exhibited dysregulated gene expression, limited in the dermis (14 differentially expressed genes) and more widespread in the epidermis (129 differentially expressed genes). ADEH+-upregulated epidermal differentially expressed genes were enriched in type 2 cytokine (IL4R , CCL22, CRLF2, IL7R), interferon (CXCL10, ICAM1, IFI44, IRF7), and IL-36γ (IL36G) inflammatory gene pathways. All ADEH+ participants exhibited type 2 cytokine and inteferon endotypes, and 87% were IL36G-high. In contrast, these endotypes were more variably expressed among ADEH- participants. ADEH+ skin also had dysregulated epidermal differentiation complex gene expression of the late-cornified envelope, S100A, and small proline-rich gene families, which are involved in skin barrier function and antimicrobial activities. Plasmacytoid dendritic cell transcriptional responses to herpes simplex virus 1 infection were unaltered by ADEH status. The study concluded that the pathobiology underlying ADEH+ risk is associated with a unique, multifaceted epidermal inflammation that accompanies dysregulation of epidermal differentiation complex genes. These findings will help direct future studies that define how these inflammatory patterns may drive risk of eczema herpeticum in AD.

Biologic and small-molecule therapy for treating moderate to severe atopic dermatitis: Mechanistic considerations

Atopic dermatitis (AD) is a complex and heterogeneous skin disease for which achieving complete clinical clearance for most patients has proven challenging through single cytokine inhibition. Current studies integrate biomarkers and evaluate their role in AD, aiming to advance our understanding of the diverse molecular profiles implicated. Although traditionally characterized as a TH2-driven disease, extensive research has recently revealed the involvement of TH1, TH17, and TH22 immune pathways as well as the interplay of pivotal immune molecules, such as OX40, OX40 ligand (OX40L), thymic stromal lymphopoietin, and IL-33. This review explores the mechanistic effects of treatments for AD, focusing on mAbs and Janus kinase inhibitors. It describes how these treatments modulate immune pathways and examines their impact on key inflammatory and barrier biomarkers.

Secondary Bacterial Infections in Patients with Atopic Dermatitis or Other Common Dermatoses

Secondary bacterial infections of common dermatoses such as atopic dermatitis, ectoparasitosis, and varicella zoster virus infections are frequent, with Staphylococcus aureus and Streptococcus pyogenes being the bacteria most involved. There are also Gram-negative infections secondary to common dermatoses such as foot dyshidrotic eczema and tinea pedis. Factors favoring secondary bacterial infections in atopic dermatitis, ectoparasitosis, and varicella zoster virus infections mainly include an epidermal barrier alteration as well as itch. Mite-bacteria interaction is also involved in scabies and some environmental factors can promote Gram-negative bacterial infections of the feet. Furthermore, the bacterial ecology of these superinfections may depend on the geographical origin of the patients, especially in ectoparasitosis. Bacterial superinfections can also have different clinical aspects depending on the underlying dermatoses. Subsequently, the choice of class, course, and duration of antibiotic treatment depends on the severity of the infection and the suspected bacteria, primarily targeting S. aureus. Prevention of these secondary bacterial infections depends first and foremost on the management of the underlying skin disorder. At the same time, educating the patient on maintaining good skin hygiene and reporting changes in the primary lesions is crucial. In the case of recurrent secondary infections, decolonization of S. aureus is deemed necessary, particularly in atopic dermatitis.

Does Molluscum Contagiosum Need to be Managed Differently in Atopic Children?

The association between molluscum contagiosum and concomitant atopic dermatitis and its impact on clinical features and treatment outcomes remains unclear. This retrospective study, conducted in the paediatric dermatology clinic of a tertiary medical centre, aimed to compare molluscum patients with and without atopic dermatitis. A total of 615 children with molluscum were included, 13.17% of whom had atopic dermatitis. While the latter group exhibited higher lesion count and itchiness (p=0.026 and p=0.044, respectively), no significant differences were observed in average lesion diameter, ulceration, purulence, and erythema (p=0.239, p=0.730, p=0.682, and p=0.296, respectively). Both groups showed comparable responses to molluscum-specific and supportive treatments, with no distinct difference in outcomes or recurrence of visits. It was concluded that atopic dermatitis does not exacerbate molluscum morbidity, inflammation markers, treatment outcomes or recurrence rates.

Updates in atopic dermatitis for the primary care physician: A review of advances in the understanding and treatment of atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory skin condition occurring in both pediatric and adult patients. Pruritus is a clinical hallmark of the disease, and patients with AD often experience disruptions to their quality of life. The pathogenesis of AD is a complex and multifactorial interplay between genetic factors, epidermal barrier disruption, and immune dysregulation. Clinically, AD is characterized by pruritus, eczematous skin changes, and age-specific lesion distribution patterns. Infants and young children tend to have AD lesions on their face and extensor surfaces of their extremities while older children and adults tend to have AD lesions on flexural surfaces of their extremities. Many patients also experience a chronic and relapsing disease course. Due to the chronicity and severe pruritus, lesions often undergo secondary changes like lichenification. Patients with AD can experience a number of comorbidities including other atopic disease (i.e. allergic rhinitis, asthma), skin infections, cardiovascular, and neuropsychiatric illnesses. Management of AD depends on the severity of the disease as well as the distribution of the disease. Traditionally, treatment of AD included the use of moisturizers / emollients, topical corticosteroids or topical calcineurin inhibitors, or systemic therapy with non-selective immunosuppressants such as corticosteroids, cyclosporine, azathioprine, or similar. However, in the past decade, new biologic and small molecule drugs, both topical and systemic, have become important therapeutic options for AD patients, especially for those with moderate-to-severe disease. The development of these medications, following decades of research to better understand AD, are designed to specifically target various components of immune dysregulation and inflammation implicated in the pathogenesis of AD. Their successful development and deployment now allow for an exciting new era of treatment for individuals suffering from atopic dermatitis.

Neuroimmune interplay during type 2 inflammation: Symptoms, mechanisms, and therapeutic targets in atopic diseases

Type 2 inflammation is characterized by overexpression and heightened activity of type 2 cytokines, mediators, and cells that drive neuroimmune activation and sensitization to previously subthreshold stimuli. The consequences of altered neuroimmune activity differ by tissue type and disease; they include skin inflammation, sensitization to pruritogens, and itch amplification in atopic dermatitis and prurigo nodularis; airway inflammation and/or hyperresponsiveness, loss of expiratory volume, airflow obstruction and increased mucus production in asthma; loss of sense of smell in chronic rhinosinusitis with nasal polyps; and dysphagia in eosinophilic esophagitis. We describe the neuroimmune interactions that underlie the various sensory and autonomic pathologies in type 2 inflammatory diseases and present recent advances in targeted treatment approaches to reduce type 2 inflammation and its associated symptoms in these diseases. Further research is needed to better understand the neuroimmune mechanisms that underlie chronic, sustained inflammation and its related sensory pathologies in diseases associated with type 2 inflammation.

Infections in Children Aged 6 Months to 5 Years Treated with Dupilumab in a Placebo-Controlled Clinical Trial of Moderate-to-Severe Atopic Dermatitis

BACKGROUND

Patients with atopic dermatitis (AD), particularly infants and young children, are at greater risk of developing skin infections. In this study, we assessed infection rates in AD patients aged 6 months to 5 years treated with dupilumab.

METHODS

In LIBERTY AD PRESCHOOL, a double-blind, placebo-controlled, phase III clinical trial, children aged 6 months to 5 years with moderate-to-severe AD were randomized 1:1 to subcutaneous dupilumab or placebo, with concomitant low-potency topical corticosteroids, every 4 weeks for 16 weeks. Exposure-adjusted infection rates were used to compare treatment groups.

RESULTS

The analysis included 162 patients, of whom 83 received dupilumab and 79 received placebo. Total infection rates were not significantly different between the dupilumab and placebo groups (rate ratio [RR] 0.75, 95% CI 0.48-1.19; p = 0.223). Non-herpetic adjudicated skin infections and bacterial infections were significantly less frequent with dupilumab versus placebo (non-herpetic skin infections: RR 0.46, 95% CI 0.21-0.99; p = 0.047; bacterial infections: RR 0.09, 95% CI 0.01-0.67; p = 0.019), and the number of patients using systemic anti-infective medication was significantly lower in the dupilumab group (RR 0.52, 95% CI 0.30-0.89; p = 0.019). There were no significant differences in the number of herpetic infections between the dupilumab and placebo groups (RR 1.17, 95% CI 0.31-4.35; p = 0.817). The number of patients with two or more infection events was significantly higher in the placebo group (RR 0.29, 95% CI 0.12-0.68; p = 0.004), and no severe or serious infections (including eczema herpeticum) were observed among patients receiving dupilumab.

CONCLUSIONS

These data suggest that dupilumab treatment in infants and children younger than 6 years with AD does not increase overall risk of infections and is associated with a reduced risk of bacterial and non-herpetic skin infections compared with placebo, resulting in a reduced need for anti-infective medication.

TRIAL REGISTRATION

The trial was registered with ClinicalTrials.gov with ID number NCT03346434 on November 17, 2017. INFOGRAPHIC.

Tetramethylpyrazine-loaded liposomes surrounded by hydrogel based on sodium alginate and chitosan as a multifunctional drug delivery System for treatment of atopic dermatitis

Tetramethylpyrazine (TMP) has low bioavailability due to its fast metabolism and short half-life, which is not conducive to transdermal treatment of atopic dermatitis (AD). Therefore, in this study, TMP was encapsulated into liposomes (Lip) by film dispersion method, and then the surface of Lip was modified by sodium alginate (ALG) and chitosan (CS). The tetramethylpyrazine-loaded liposomes in sodium alginate chitosan hydrogel called T-Lip-AC hydrogel. In vitro experiments, we found that T-Lip-AC hydrogel not only had the antibacterial effect of CS, but also enhanced the anti-inflammatory and antioxidant effects of TMP. In addition, T-Lip-AC hydrogel could also provide a moist healing environment for AD dry skin and produce better skin permeability, and can also achieve sustained drug release, which is conducive to the treatment of AD. The lesions induced by 1-chloro-2,4-dinitrobenzene were used as the AD lesions model to test the therapeutic effect of the T-Lip-AC hydrogel on AD in vivo. The studies have showed that T-Lip-AC hydrogel could effectively promote wound healing. Therefore, we have developed a T-Lip-AC hydrogel as multifunctional hydrogel drug delivery system, which could become an effective, safe and novel alternative treatment method for treating AD.

Comorbidities in childhood atopic dermatitis: A population-based study

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is associated with allergic comorbidities. However, studies examining comorbidities in childhood AD are incomplete, which may contribute to suboptimal care.

OBJECTIVE

The objective was to compare the risk of developing different allergic and non-allergic comorbidities among children with AD to that of a matched non-AD reference cohort in Sweden.

METHODS

This was a nationwide population-based cohort study using longitudinal data from primary and specialist care registers. Patients with AD were identified by confirmed diagnosis in primary or specialist care. The non-AD reference cohort was randomly drawn from the general population and matched 1:1 with the AD patients. The risk of developing the following conditions was evaluated: hypersensitivity and allergic disorders, neurological disorders, psychiatric disorders, infections, immunological and inflammatory disorders, Type 1 diabetes (T1D), endocrine and metabolic disorders, skeletal disorders, ocular disorders and malignancies.

RESULTS

This study included 165,145 patients with AD (mild-to-moderate [n = 126,681] and severe [n = 38,464]) and an equally sized reference cohort. Patients with AD displayed a higher risk of developing comorbid conditions for all investigated categories, except for T1D and skeletal disorders, compared with the reference cohort. The highest risk compared with the reference cohort was observed for hypersensitivity and allergic disorders (hazard ratio [HR]: 3.87), followed by malignancies (HR: 2.53) and immunological and inflammatory disorders (HR: 2.36). Patients with AD also had higher risk of developing multiple comorbidities (≥2). The risk of comorbidity onset increased alongside AD severity and patients with active AD were associated with increased risk of comorbidity onset compared with patients in remission.

CONCLUSIONS

The clinical burden of AD is substantial for children with AD and patients are at an increased risk of developing several comorbid conditions extending beyond the atopic march. Our results also showed a positive association between worsening severity of AD and an increased risk of comorbidity onset.

Belgian atopic dermatitis guidelines

Atopic dermatitis (AD) is one of the most common, bothersome and difficult to treat skin disorders. Recent introduction of new systemic treatments has revolutionized the management of AD. The goal of this guideline is to provide evidence-based recommendations for the management of patients suffering from atopic dermatitis that easily can be implemented in clinical practice. These recommendations were developed by 11 Belgian AD experts. Comments of all experts on the proposed statements were gathered, followed by an online voting session. The most relevant strategies for the management and treatment of AD in the context of the Belgian health care landscape are discussed. General measures, patient education and adequate topical treatment remain the cornerstones of AD management. For moderate to severe AD, the introduction of biologics and JAK inhibitors show unprecedented efficacy, although currently access is limited to a subgroup of patients meeting the reimbursement criteria.

Increased S. aureus colonization and reduced antimicrobial peptide expression in erythrodermic psoriasis

BACKGROUND

Erythrodermic psoriasis (EP) is a severe and rare condition characterized by prominent erythema and scaling over 75 % of the body surface area. Unlike psoriasis vulgaris (PV), EP carries high risk of systemic involvement, including superficial skin infections and sepsis, particularly those caused by Staphylococcus aureus.

OBJECTIVE

To explore the microecological characteristics of EP and detect the levels of antimicrobial peptides (AMPs) in both skin and serum of EP patients.

METHODS

In this study, skin microbiomes of 10 EP patients were analyzed through 16S rRNA gene sequencing. The expressions of AMPs, Interleukin-4/13 (IL-4/13), Interleukin-17 (IL-17) and Interferon-γ (IFN-γ) in skin were detected via immunohistochemical staining and serum levels of AMP were evaluated by ELISA. We also enrolled 10 AD and 10 PV patients as controls.

RESULTS

EP patients retained rich microbial diversity, dominated by S. aureus. The AMPs of hBD2, LL-37, and RNase7 in EP keratinocytes were significantly lower than those in PV, but higher than those in AD. The expression levels of IL-4, IL-13 and IFN-γ in lesions are similar between EP and AD, but quite different from PV. What's more, the serum AMP levels in EP were similar to those in PV while significantly lower than in AD.

CONCLUSION

We found EP patients have a rich microbial diversity dominated by S. aureus in lesions, while lower serum and skin AMPs expressions, which may account for the increased incidence of S. aureus cutaneous infections and sepsis in EP patients.

Atopic Disease as a Risk Factor for Recurrent Herpetic Keratitis

Recurrent herpetic keratitis is a leading cause of blindness worldwide. In this population-based cross-sectional study, the medical records of Israeli adolescents and young adults who underwent systematic preconscription evaluation for mandatory military service were reviewed. The prevalence of atopic conjunctival disease was evaluated in cases with and without documented recurrent herpetic keratitis. The association was tested using uni- and multivariant analyses. Overall, 940,892 adolescents and young adults were included. The mean age was 17.57 ± 1.50 years (range 16-20 years), and 40.70% of participants were female. Recurrent herpetic keratitis was documented in 160 cases, with a prevalence of 0.017% in this age group. Compared to the general population, patients with recurrent herpetic keratitis were significantly more likely to be males (p = 0.003) with a concomitant diagnosis of atopic conjunctival disease (p < 0.0001). Patients with atopic conjunctival disease were 10.60-fold more likely to experience recurrent herpetic keratitis (95% confidence interval (CI): 6.76-16.64, p < 0.0001). Upon multivariate analysis, the results remained significant (p < 0.001). Cases of severe atopic conjunctival disease were more prone to recurrent HSV keratitis compared to mild cases (p < 0.001). These findings suggest that the timely appropriate treatment of atopic conjunctival disease may help reduce the frequency and severity of recurrent HSV keratitis and its complications.

Atopic Dermatitis: Disease Background and Risk Factors

Multiple risk factors have been associated with the development of atopic dermatitis (AD). Recent advances in understanding the role of genetics in this disease have been made, with discovery of the filaggrin (FLG) gene as the most notable so far. In addition to FLG gene mutations as a risk factor for AD, a positive family history of atopic or allergic disease in either parent has been shown to confer a greater risk of developing AD. Atopic dermatitis usually presents early in life and is thought to represent the initial step in the "atopic march," which is characterized by the development of other atopic diseases later in life such as asthma, allergic rhinitis, and/or rhinoconjunctivitis, food allergies, and hay fever. Other comorbid diseases that have been associated with AD include increase risk of viral and bacterial skin infections, neuropsychiatric diseases such as attention-deficit hyperactivity disorders (ADHD), and autistic spectrum disorder (ASD). Patients with AD have also been found to have worse sleep quality overall compared to patients without AD. In this chapter, we will discuss the risk factors associated with development of atopic dermatitis as well as the most commonly reported comorbidities in patients with this disease.

Skin infections during dupilumab monotherapy in moderate-to-severe atopic dermatitis - a meta-analysis of randomized clinical trials

OBJECTIVE

Atopic dermatitis (AD) increases the risk of bacterial and viral cutaneous infections. This study assesses the risk of skin infections related to dupilumab monotherapy in moderate-to-severe AD.

METHODS

We searched PubMed/Medline, Embase, Web of Science, ClinicalTrials.gov, and Cochrane Library. For gray literature, Google Scholar was searched. A meta-analysis of randomized clinical trials (RCTs) for overall skin infections, eczema herpeticum, nonherpetic skin infections and subgroup meta-analysis based on overall herpetic infection type was performed.

RESULTS

We observed a statistically significant (p < 0.005) lower incidence rate in the dupilumab group compared to placebo for overall skin infections (Risk Ratio [RR] = 0.59, 95% confidence interval [CI]: [0.47, 0.75], P < 0.0001) and nonherpetic skin infections (RR = 0.42, 95% CI: [0.27, 0.66], P = 0.0001). For herpetic infections in 2b phase studies a meta-analysis demonstrated significantly higher events in dupilumab group compared to placebo (RR = 3.38, 95% CI: [1.98, 5.76], P < 0.00001, test for subgroup differences: P = 0.02, I2 = 65.6%).

CONCLUSIONS

In moderate-to-severe AD, dupilumab in monotherapy may be an effective and safe therapeutic approach, not associated with an increased risk of overall skin infections and nonherpetic skin infections. Due to the lack of statistical significance in heterogeneity associated with potential confounders in some cases, results should be interpreted cautiously.

REGISTRATION

The meta-analysis was registered in PROSPERO, ID: CRD42023441346.

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.

Safety of baricitinib for the treatment of atopic dermatitis over a median of 1.6 years and up to 3.9 years of treatment: an updated integrated analysis of eight clinical trials

BACKGROUND

Baricitinib, a selective Janus kinase (JAK)1/JAK2 inhibitor, is approved for treatment of moderate-to-severe atopic dermatitis (AD) in adults.

OBJECTIVES

We report integrated baricitinib safety data in patients with up to 3.9-years exposure.

METHODS

Three datasets from the integrated AD clinical trial program were analyzed: placebo-controlled, 2-mg-4-mg extended, and All-bari. Data cutoffs were up to 21-December-2021 for long-term extension studies. Proportions of patients with events and incidence rates (IR)/100 patient years (PY) at risk were calculated.

RESULTS

2636 patients received baricitinib for 4628.4 PY. Discontinuation due to adverse events was low (IR = 3.4). IRs in All-bari were: serious adverse events, 5.2; infection, 67.2 (any infection), 6.7 (herpes simplex), 2.8 (herpes zoster), and 0.3 (opportunistic infections). Adverse events of special interest in All-bari included seven patients with positively adjudicated major adverse cardiovascular events (MACE) (IR = 0.15), three pulmonary emboli (PE) (IR = 0.06), 14 malignancies excluding nonmelanoma skin cancer (IR = 0.3), one gastrointestinal perforation (IR = 0.02), and four deaths (IR = 0.1). No deep vein thromboses (DVT) or tuberculosis were reported.

CONCLUSION

In this analysis, baricitinib maintained a similar safety profile to earlier analyses with no new safety signals. Rates of MACE, DVT/PE, malignancies, and serious infections were within ranges of background rates in patients with AD.

CLINICALTRIALS.GOV

NCT02576938 (JAHG), NCT03334396 (JAHL; BREEZE-AD1), NCT03334422 (JAHM; BREEZE-AD2), NCT03334435 (JAHN; BREEZE-AD3), NCT03428100 (JAIN; BREEZE-AD4), NCT03435081 (JAIW; BREEZE-AD5), NCT03559270 (JAIX; BREEZE-AD6), NCT03733301 (JAIY; BREEZE-AD7).

IL-4 receptor alpha blockade dampens allergic inflammation and upregulates IL-17A expression to promote Saureus clearance in antigen sensitized mouse skin

BACKGROUND

Skin colonization with Staphylococcus aureus aggravates atopic dermatitis and exaggerates allergic skin inflammation in mice. IL-4 receptor α (IL-4Rα) blockade is beneficial in atopic dermatitis and reduces Saureus skin colonization through unknown mechanisms. The cytokine IL-17A restrains Saureus growth.

OBJECTIVES

This study sought to examine the effect of IL-4Rα blockade on Saureus colonization at sites of allergic skin inflammation in mice and determine the mechanism involved.

METHODS

BALB/c mice were epicutaneously sensitized with ovalbumin (OVA). Immediately after, PSVue 794-labeled S aureus strain SF8300 or saline was applied and a single dose of anti-IL-4Rα blocking antibody, a mixture of anti-IL-4Rα and anti-IL-17A blocking antibodies, or IgG isotype controls were administered intradermally. Saureus load was assessed 2 days later by in vivo imaging and enumeration of colony forming units. Skin cellular infiltration was examined by flow cytometry and gene expression by quantitative PCR and transcriptome analysis.

RESULTS

IL-4Rα blockade decreased allergic skin inflammation in OVA-sensitized skin, as well as in OVA-sensitized and Saureus-exposed skin, evidenced by significantly decreased epidermal thickening and reduced dermal infiltration by eosinophils and mast cells. This was accompanied by increased cutaneous expression of Il17a and IL-17A-driven antimicrobial genes with no change in Il4 and Il13 expression. IL-4Rα blockade significantly decreased Saureus load in OVA-sensitized and S aureus-exposed skin. IL-17A blockade reversed the beneficial effect of IL-4Rα blockade on Saureus clearance and reduced the cutaneous expression of IL-17A-driven antimicrobial genes.

CONCLUSIONS

IL-4Rα blockade promotes Saureus clearance from sites of allergic skin inflammation in part by enhancing IL-17A expression.

History of S. aureus Skin Infection Significantly Associates with History of Eczema Herpeticum in Patients with Atopic Dermatitis

INTRODUCTION

Patients with atopic dermatitis (AD) are uniquely susceptible to a number of serious viral skin complications, including eczema herpeticum (EH), caused by herpes simplex virus. This study explored the associations between biomarkers of epithelial barrier dysfunction, type 2 immunity, Staphylococcus aureus infection, and S. aureus-specific immunoglobulin responses in a cohort of AD subjects with and without a history of EH (EH+ and EH-, respectively).

METHODS

A total of 112 subjects with AD (56 EH+, 56 EH-), matched by age and AD severity, were selected from a registry of over 3000 AD subjects. Logistic regression was used to test the association between history of S. aureus skin infection and history of EH, while controlling for a number of confounders.

RESULTS

Compared to those without a history of S. aureus skin infection, subjects with a history of S. aureus skin infection were found to have more than sixfold increased odds of having a history of EH (6.60, 95% confidence interval [CI]: 2.00-21.83), after adjusting for history of other viral skin infections (molluscum contagiosum virus, human papillomavirus), serum total IgE, and IgG against the S. aureus virulence factor SElX.

CONCLUSIONS

These findings indicate an important relationship between S. aureus skin infections and EH.

Background factors predicting the occurrence of herpes zoster in atopic dermatitis patients treated with upadacitinib

Upadacitinib, an oral Janus kinase 1 inhibitor approved for treating atopic dermatitis (AD), can cause adverse events such as herpes zoster (HZ) and acne. We aimed to identify background factors predicting the occurrence of HZ and acne during upadacitinib treatment in patients with AD. From August 2021 to December 2022, 112 Japanese patients with moderate-to-severe AD (aged ≥12 years) were treated with upadacitinib 15 mg/day (78 patients) or 30 mg/day (34 patients) plus topical corticosteroids or delgocitinib limited to head and neck for 3-9 months. AD patients with the occurrence of HZ during upadacitinib treatment had higher incidences for history of HZ and of bronchial asthma than those without in the upadacitinib 15 mg, 30 mg, and whole groups. AD patients with occurrence of HZ had higher pretreatment values of lactate dehydrogenase and eczema area and severity index on head and neck compared to those without in the upadacitinib 15 mg and whole groups. Logistic regression analysis revealed that history of HZ was associated with the occurrence of HZ in the upadacitinib 15 mg and whole groups. The proportion of underage patients (<18 years) was higher in patients with occurrence of acne compared to those without in the upadacitinib 30 mg group, but no significant differences were found in the other background factors between the two patient populations. History of HZ may predict the occurrence of HZ during upadacitinib treatment in patients with AD.

S. aureus virulence factors decrease epithelial barrier function and increase susceptibility to viral infection

Individuals with atopic dermatitis (AD) are highly colonized by Staphylococcus aureus and are more susceptible to severe viral complications. We hypothesized that S. aureus secreted virulence factors may alter keratinocyte biology to enhance viral susceptibility through disruption of the skin barrier, impaired keratinocyte differentiation, and/or inflammation. To address this hypothesis, human keratinocytes were exposed to conditioned media from multiple S. aureus strains that vary in virulence factor production (USA300, HG003, and RN4220) or select purified virulence factors. We have identified the S. aureus enterotoxin-like superantigen SElQ, as a virulence factor of interest, since it is highly produced by USA300 and was detected on the skin of 53% of AD subjects (n = 72) in a study conducted by our group. Treatment with USA300 conditioned media or purified SElQ resulted in a significant increase in keratinocyte susceptibility to infection with vaccinia virus, and also significantly decreased barrier function. Importantly, we have previously demonstrated that keratinocyte differentiation influences susceptibility to viral infection, and our qPCR observations indicated that USA300 S. aureus and SElQ alter differentiation in keratinocytes. CRISPR/Cas9 was used to knock out CD40, a potential enterotoxin receptor on epithelial cells. We found that CD40 expression on keratinocytes was not completely necessary for SElQ-mediated responses, as measured by proinflammatory cytokine expression and barrier function. Together, these findings support that select S. aureus virulence factors, particularly SElQ, enhance the susceptibility of epidermal cells to viral infection, which may contribute to the increased cutaneous infections observed in individuals with AD. IMPORTANCE Staphylococcus aureus skin colonization and infection are frequently observed in individuals with atopic dermatitis. Many S. aureus strains belong to the clonal group USA300, and these strains produce superantigens including the staphylococcal enterotoxin-like Q (SElQ). Our studies highlight that SElQ may play a key role by altering keratinocyte differentiation and reducing barrier function; collectively, this may explain the AD-specific enhanced infection risk to cutaneous viruses. It is unclear what receptor mediates SElQ's effects on keratinocytes. We have shown that one putative surface receptor, CD40, was not critical for its effects on proinflammatory cytokine production or barrier function.

Hand Eczema in the Polish Female Population

BACKGROUND

This study aims to investigate the prevalence of hand eczema, its association with disinfectant usage during the COVID-19 pandemic, and potential correlations with age and dermatological history on hand symptoms in the Polish female population.

METHODS

A personalized online questionnaire was administered from January to March 2021 to 142 participants, including individuals with hand eczema. The questionnaire addressed demographics, dermatological history, disinfectant usage, and symptoms experienced during the pandemic.

RESULTS

The prevalence of hand eczema was higher in younger adults (aged 18-35), with significant exacerbations reported due to increased disinfectant usage. Respondents with a dermatological history were more susceptible to new skin symptoms during the pandemic. The quality of life was substantially impacted, particularly in individuals with hand skin dermatoses.

CONCLUSIONS

The COVID-19 pandemic had a considerable influence on hand eczema, affecting prevalence, symptoms, and quality of life. Disinfectant usage emerged as a key factor in exacerbating hand skin lesions. Further research is warranted to explore the influence of specific disinfecting agents and improve treatment guidelines for personalized management of hand eczema. Despite limitations in the online survey method, these findings highlight the importance of proactive healthcare support for individuals with hand eczema during challenging times.

Progressive accumulation of hyperinflammatory NKG2D low NK cells in early childhood severe atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that often precedes the development of food allergy, asthma, and allergic rhinitis. The prevailing paradigm holds that a reduced frequency and function of natural killer (NK) cell contributes to AD pathogenesis, yet the underlying mechanisms and contributions of NK cells to allergic co-morbidities remain ill-defined. Herein, analysis of circulating NK cells in a longitudinal early life cohort of children with AD revealed a progressive accumulation of NK cells with low expression of the activating receptor NKG2D, which was linked to more severe AD and sensitivity to allergens. This was most notable in children co-sensitized to food and aero allergens, a risk factor for development of asthma. Individual-level longitudinal analysis in a subset of children revealed co-incident reduction of NKG2D on NK cells with acquired or persistent sensitization, and this was associated with impaired skin barrier function assessed by transepidermal water loss. Low expression of NKG2D on NK cells was paradoxically associated with depressed cytolytic function but exaggerated release of the proinflammatory cytokine TNF-α. These observations provide important insights into a potential mechanism underlying the development of allergic co-morbidity in early life in children with AD which involves altered NK-cell functional responses, and define an endotype of severe AD.

From gut to skin: exploring the potential of natural products targeting microorganisms for atopic dermatitis treatment

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease. Recent studies have revealed that interactions between pathogenic microorganisms, which have a tendency to parasitize the skin of AD patients, play a significant role in the progression of the disease. Furthermore, specific species of commensal bacteria in the human intestinal tract can have a profound impact on the immune system by promoting inflammation and pruritogenesis in AD, while also regulating adaptive immunity. Natural products (NPs) have emerged as promising agents for the treatment of various diseases. Consequently, there is growing interest in utilizing natural products as a novel therapeutic approach for managing AD, with a focus on modulating both skin and gut microbiota. In this review, we discuss the mechanisms and interplay between the skin and gut microbiota in relation to AD. Additionally, we provide a comprehensive overview of recent clinical and fundamental research on NPs targeting the skin and gut microbiota for AD treatment. We anticipate that our work will contribute to the future development of NPs and facilitate research on microbial mechanisms, based on the efficacy of NPs in treating AD.

Next-generation nanomaterials: advancing ocular anti-inflammatory drug therapy

Ophthalmic inflammatory diseases, including conjunctivitis, keratitis, uveitis, scleritis, and related conditions, pose considerable challenges to effective management and treatment. This review article investigates the potential of advanced nanomaterials in revolutionizing ocular anti-inflammatory drug interventions. By conducting an exhaustive analysis of recent advancements and assessing the potential benefits and limitations, this review aims to identify promising avenues for future research and clinical applications. The review commences with a detailed exploration of various nanomaterial categories, such as liposomes, dendrimers, nanoparticles (NPs), and hydrogels, emphasizing their unique properties and capabilities for accurate drug delivery. Subsequently, we explore the etiology and pathophysiology of ophthalmic inflammatory disorders, highlighting the urgent necessity for innovative therapeutic strategies and examining recent preclinical and clinical investigations employing nanomaterial-based drug delivery systems. We discuss the advantages of these cutting-edge systems, such as biocompatibility, bioavailability, controlled release, and targeted delivery, alongside potential challenges, which encompass immunogenicity, toxicity, and regulatory hurdles. Furthermore, we emphasize the significance of interdisciplinary collaborations among material scientists, pharmacologists, and clinicians in expediting the translation of these breakthroughs from laboratory environments to clinical practice. In summary, this review accentuates the remarkable potential of advanced nanomaterials in redefining ocular anti-inflammatory drug therapy. We fervently support continued research and development in this rapidly evolving field to overcome existing barriers and improve patient outcomes for ophthalmic inflammatory disorders.

Bacterial Metabolites and Inflammatory Skin Diseases

The microbiome and gut-skin axis are popular areas of interest in recent years concerning inflammatory skin diseases. While many bacterial species have been associated with commensalism of both the skin and gastrointestinal tract in certain disease states, less is known about specific bacterial metabolites that regulate host pathways and contribute to inflammation. Some of these metabolites include short chain fatty acids, amine, and tryptophan derivatives, and more that when dysregulated, have deleterious effects on cutaneous disease burden. This review aims to summarize the knowledge of wealth surrounding bacterial metabolites of the skin and gut and their role in immune homeostasis in inflammatory skin diseases such as atopic dermatitis, psoriasis, and hidradenitis suppurativa.

Phenotypic and Endotypic Determinants of Atopic Dermatitis Severity From the Atopic Dermatitis Research Network (ADRN) Registry

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin condition with a highly variable clinical phenotype.

OBJECTIVE

This study aimed to identify historical and clinical features and biomarkers associated with AD severity.

METHODS

A US registry of extensively phenotyped AD participants (aged 0.73-80 years) were enrolled at 9 academic centers. Information on family and personal medical history, examination, skin swabs (culture), and serum biomarkers was collected to evaluate their association with AD severity.

RESULTS

Participants with AD (N = 2862) whose disease was categorized as mild (11.6%), moderate (58.0%), or severe (30.4%) based on Rajka-Langeland scoring were enrolled. The trend test, when adjusting for gender, race, and age, demonstrated that severity was strongly (P ≤ .04) associated with a personal/family history of allergic disorders, history of alopecia, exposure to passive smoke, ocular herpes infection, skin bacterial and viral infections, and history of arrhythmia. Features observed more frequently (P ≤ .002), as a function of severity, included skin infections (impetigo, human papillomavirus, and molluscum contagiosum virus), Staphylococcus aureus colonization, excoriations, hyperlinear palms, ichthyosis, blepharitis, conjunctivitis, ectropion, and wheezing. Serum IgE, allergen and food (≤6 years) Phadiatop, and eosinophilia were strongly linked to severity (P < .001).

CONCLUSIONS

In a diverse US AD population, severity was associated with a history of atopic disorders, skin and extracutaneous bacterial and viral infections (by history and physical examination), higher IgE, eosinophilia and allergen sensitization, atopic skin manifestations (ie, excoriation, hyperlinear palms, and ichthyosis), and atopic ocular features (ie, blepharitis, conjunctivitis, and ectropion) as well as asthma findings (ie, wheezing). Data from our prospective registry significantly advance our understanding of AD phenotypes and endotypes, which is critical to achieve optimal management.

Safety of Lebrikizumab in Adults and Adolescents with Moderate-to-Severe Atopic Dermatitis: An Integrated Analysis of Eight Clinical Trials

BACKGROUND

Lebrikizumab is a monoclonal antibody that binds with high affinity to interleukin (IL)-13, thereby blocking the downstream effects of IL-13 with high potency.

OBJECTIVES

To report integrated safety of lebrikizumab in adults and adolescents with moderate-to-severe atopic dermatitis from phase 2 and 3 studies.

METHODS

Five double-blind, randomized placebo-controlled studies; one randomized open-label study; one adolescent open-label, single-arm study; and one long-term safety study were summarized in two datasets: (1) placebo-controlled week 0-16 (All-PC Week 0-16) in patients who received lebrikizumab 250 mg every 2 weeks (LEBQ2W) versus placebo and (2) patients who received any dose of lebrikizumab at any time during the studies (All-LEB). Exposure-adjusted incidence rates (IR)/100 patient-years (PY) are provided.

RESULTS

A total of 1720 patients received lebrikizumab (1637.0 PY exposure). In All-PC Week 0-16, the frequency of treatment-emergent adverse events (TEAEs) was similar between treatment groups; most events were nonserious and mild or moderate in severity. The most frequently reported TEAEs were atopic dermatitis (placebo) and conjunctivitis (LEBQ2W). Frequencies of conjunctivitis cluster were 2.5% (placebo) and 8.5% (LEBQ2W), and all events were mild or moderate (All-LEB 10.6%, IR, 12.2). Frequencies of injection site reactions were 1.5% (placebo) and 2.6% (LEBQ2W; All-LEB 3.1%, IR, 3.3). Frequencies of adverse events leading to treatment discontinuation were 1.4% (placebo) and 2.3% (LEBQ2W; All-LEB 4.2%, IR, 4.5).

CONCLUSION

The safety profile for lebrikizumab consisted of TEAEs that were mostly nonserious, mild or moderate in severity, and did not lead to treatment discontinuation. The safety profile was similar in both adults and adolescents.

CLINICALTRIALS

GOV: NCT02465606, NCT02340234, NCT03443024, NCT04146363, NCT04178967, NCT04250337, NCT04250350, NCT04392154 Safety of lebrikizumab in adults and adolescents with moderate-to-severe atopic dermatitis: an integrated analysis of eight clinical trials (MP4 34165 KB).

Human umbilical cord mesenchymal stem cell treatment alleviates symptoms in an atopic dermatitis-like mouse model

BACKGROUND

Atopic dermatitis (AD) is one of the most common immune and inflammatory skin disorders, leading to insufferable itching and skin abnormalities that seriously affect life quality of patients. There are still huge unmet needs for long-term and effective disease control, despite currently available therapies. Evidenced by some preclinical and clinical studies of AD treatment with stem cells, stem cell treatment could significantly and effectively ameliorate AD symptoms.

OBJECTIVES

To elucidate underlying mechanisms of how stem cells therapy alleviates AD-like symptoms.

METHODS

An AD-like mouse model was constructed and treated with mesenchymal stem cells (MSCs) subcutaneously or subcutaneously combined with intravenously. The differentially expressed genes were sorted out from RNA sequencing results of dorsal skin and blood.

RESULTS

Two injection routes of MSCs could alleviate AD-like symptoms and pathologic changes of the skin and immune organs. RNA sequencing of dorsal skin sections and blood provided gene expression signatures for amelioration of skin defects, inflammatory and immune modulation by MSCs, as well as common AD molecular markers for the skin and blood, which may benefit for clinical diagnosis. IL-1β and its signaling pathway were specifically found to be associated with the development of AD-like dermatitis lesions. MSC treatment effectively inhibited the JAK-STAT pathway and receptors of IL-4, IL-13, IL-17, and IgE.

CONCLUSIONS

MSC therapy could regulate abnormal immune and inflammatory status in AD. Mechanistic exploration will contribute to the development of personalized AD treatment based on MSCs.

JAK Signaling Is Critically Important in Cytokine-Induced Viral Susceptibility of Keratinocytes

Little is known about whether type 1 (IFNγ), 2 (IL-4/IL-13), or 3 (IL-17A/IL-22) cytokines affect the susceptibility of keratinocytes (KC) to viruses. These immune pathways predominate in various skin diseases: lupus, atopic dermatitis (AD), and psoriasis, respectively. Janus kinase inhibitors (JAKi) are approved to treat both AD and psoriasis, and are in clinical development for lupus. We evaluated whether these cytokines alter viral susceptibility of KC and determined if this effect is modulated by treatment with JAKi. Viral susceptibility to vaccinia virus (VV) or herpes simplex virus-1 (HSV-1) ± JAKi was assessed in immortalized and primary human KC pretreated with cytokines. Exposure to type 2 (IL-4 + IL-13) or the type 3 (IL-22) cytokines significantly increased KC viral susceptibility. Specifically, there was a peak increase of 12.2 ± 3.1-fold (IL-4 + IL-13) or 7.7 ± 2.8-fold (IL-22) in VV infection as measured by plaque number. Conversely, IFNγ significantly reduced susceptibility to VV (63.1 ± 64.4-fold). The IL-4 + IL-13-induced viral susceptibility was reduced (44 ± 16%) by JAK1 inhibition, while the IL-22-enhanced viral susceptibility was diminished (76 ± 19%) by TYK2 inhibition. IFNγ-mediated resistance to viral infection was reversed by JAK2 inhibition (366 ± 294% increase in infection). Cytokines expressed in AD skin (IL-4, IL-13, IL-22) increase KC viral susceptibility while IFNγ is protective. JAKi that target JAK1 or TYK2 reversed cytokine-enhanced viral susceptibility, while JAK2 inhibition reduced the protective effects of IFNγ.

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.

Recent advance in management of herpes simplex in Japan

Herpes simplex, a common infection caused by the herpes simplex virus (HSV), is transmitted through contact of the skin/mucous membrane and establishes latency in the sensory ganglia for the rest of the life of the host. HSV occasionally reactivates and forms blisters around the lips or genitalia in some patients. Repeated overt symptoms, and, much more frequent, subclinical reactivation in the mucosa, make the host retain anti-HSV immunity continuously, resulting in maintaining steadily elevated antibody titer at any point after infection. Clinical symptoms differ in primary infection and recurrence. Primary infections sometimes manifest as severe symptoms such as fever and lymphadenopathy in addition to blisters/erosions of the skin, gingiva, lips, and oral mucosa, while recurrent herpes is generally mild. Diagnosing typical herpes simplex is not difficult, but when the course and manifestations are typical, definitive tests to identify HSV infection are limited since serology is not useful except with primary infection. For treatment, safe and effective oral antiviral drugs are available. Patient-initiated therapy is a new method of administration labeled in Japan. Amenamevir, an inhibitor of viral helicase primase, is available in Japan and labeled in addition to herpes zoster. These new diagnostic and therapeutic tools should be used for better management of herpes simplex.

Atopic dermatitis complicated by recurrent eczema herpeticum is characterized by multiple, concurrent epidermal inflammatory endotypes

BACKGROUND

A subgroup of atopic dermatitis (AD) patients suffer from recurrent, disseminated herpes simplex virus (HSV) skin infections, termed eczema herpeticum (EH), which can be life-threatening and contribute to AD morbidity. The pathobiology underlying ADEH is unknown.

OBJECTIVE

To determine transcriptional mechanisms of skin and immune system pathobiology that underlie ADEH disease.

METHODS

We performed whole transcriptome RNA-sequencing of non-lesional skin samples (epidermis, dermis) of AD patients with (ADEH + , n=15) and without (ADEH - , n=13) recurrent EH history, and healthy controls (HC, n=15). We also performed RNA-sequencing on plasmacytoid dendritic cells (pDCs) collected from these participants and infected in vitro with HSV-1. Differential expression, gene set enrichment, and endotyping analyses were performed.

RESULTS

ADEH + disease was characterized by dysregulation in skin gene expression, which was limited in dermis (differentially expressed genes [DEGs]=14) and widespread in epidermis (DEGs=129). ADEH + -upregulated epidermal DEGs were enriched in type 2 cytokine (T2) ( IL4R, CCL22, CRLF2, IL7R ), interferon ( CXCL10, ICAM1, IFI44 , and IRF7) , and IL-36γ ( IL36G ) inflammatory pathway genes. At a person-level, all ADEH + participants exhibited T2 and interferon endotypes and 87% were IL36G-high. In contrast, these endotypes were more variably expressed among ADEH - participants. ADEH + patient skin also exhibited dysregulation in epidermal differentiation complex (EDC) genes within the LCE, S100 , and SPRR families, which are involved in skin barrier function, inflammation, and antimicrobial activities. pDC transcriptional responses to HSV-1 infection were not altered by ADEH status.

CONCLUSIONS

ADEH + pathobiology is characterized by a unique, multi-faceted epidermal inflammation that accompanies dysregulation in the expression of EDC genes.

Key Messages

AD patients with a history of recurrent EH exhibit molecular skin pathobiology that is similar in form, but more severe in degree, than in AD patients without this complication. Non-lesional skin of ADEH + patients concurrently exhibits excessive type 2 cytokine, interferon, and IL-36γ-driven epidermal inflammation. Expression of these inflammatory skin endotypes among ADEH + patients is associated with dysregulation in expression of epidermal differentiation complex genes involved in barrier function, inflammation, and antimicrobial activity.

Capsule Summary

AD patients with a history of recurrent disseminated HSV-1 skin infections form a unique molecular skin endotype group that concurrently exhibits type 2 cytokine, interferon, and IL-36γ-driven skin inflammation, accompanied by dysregulation in expression of epidermal differentiation complex genes involved in barrier function, inflammation, and antimicrobial activity.

Secretory proteins in the orchestration of microbial virulence: The curious case of Staphylococcus aureus

Microbial virulence showcases an excellent model for adaptive changes that enable an organism to survive and proliferate in a hostile environment and exploit host resources to its own benefit. In Staphylococcus aureus, an opportunistic pathogen of the human host, known for the diversity of the disease conditions it inflicts and the rapid evolution of antibiotic resistance, virulence is a consequence of having a highly plastic genome that is amenable to quick reprogramming and the ability to express a diverse arsenal of virulence factors. Virulence factors that are secreted to the host milieu effectively manipulate the host conditions to favor bacterial survival and growth. They assist in colonization, nutrient acquisition, immune evasion, and systemic spread. The structural and functional characteristics of the secreted virulence proteins have been shaped to assist S. aureus in thriving and disseminating effectively within the host environment and exploiting the host resources to its best benefit. With the aim of highlighting the importance of secreted virulence proteins in bacterial virulence, the present chapter provides a comprehensive account of the role of the major secreted proteins of S. aureus in orchestrating its virulence in the human host.

Type 2 Immunity and Its Impact on COVID-19 Infection in the Airways

Type 2 immune responses are characterized by elevated type 2 cytokines and blood eosinophilia. Emerging evidence suggests that people with chronic type 2 inflammatory lung diseases are not particularly susceptible to SARS-CoV-2 infection. Intriguingly, recent in vitro, ex vivo research demonstrates type 2 cytokines, particularly IL-13, reduce the risk of SARS-CoV-2 infection in the airway epithelium. IL-13 treatment in airway epithelial cells followed by SARS-CoV-2 diminished viral entry, replication, spread, and cell death. IL-13 reduces the expression of the angiotensin-converting enzyme 2 (ACE2) receptor in the airway epithelium and transmembrane serine protease 2 (TMPRSS2), particularly in ciliated cells. It also alters the cellular composition toward a secretory-cell-rich phenotype reducing total ciliated cells and, thus, reducing viral tropism. IL-13 enhances Muc5ac mucin and glycocalyx secretion in the periciliary layer, which acts as a physical barrier to restrict virus attachment. Moreover, type 2 airway immune cells, such as M2 alveolar macrophages, CD4+ tissue-resident memory T cells, and innate lymphoid 2 cells, may also rescue type 2 airways from SARS-CoV-2-induced adverse effects. In this review, we discuss recent findings that demonstrate how type 2 immunity alters immune responses against SARS-CoV-2 and its consequences on COVID-19 pathogenesis.

Skin Antiseptics for Atopic Dermatitis: Dissecting Facts From Fiction

Staphylococcus aureus is a known trigger and cause of infectious complications in atopic dermatitis (AD). Various antiseptics have been used in an attempt to decrease the burden of S. aureus in AD. In this Commentary, we present the evidence for and against some of the commonly used antiseptics in clinical and research settings. These agents remain attractive as an adjunct therapy for AD owing to their relative low cost and potential benefits of reducing S. aureus. Although a number of studies have evaluated the use of dilute bleach, its mechanisms remain controversial. A higher concentration of bleach than the commonly used 0.005% is likely needed for its anti-S. aureus effect. Silver-coated textiles have demonstrated anti-S. aureus effects in various studies; however, their efficacy and side effects in AD remain to be confirmed. Other antiseptics including chlorhexidine, triclosan, and triclocarban are also discussed. Variables that may affect the outcomes of these studies include length of use, concurrent application of moisturizers, and anti-inflammatory medications.

No Increased Risk of Overall Infection in Adults with Moderate-to-Severe Atopic Dermatitis Treated for up to 4 Years with Dupilumab

INTRODUCTION

Patients with atopic dermatitis (AD) have an increased risk for infections. This open-label extension study, LIBERTY AD OLE, reports the incidence of infections in adults with moderate-to-severe AD treated with dupilumab for up to 4 years.

METHODS

We evaluated infections in adults with moderate-to-severe AD treated with dupilumab 300 mg weekly (qw) or every 2 weeks (q2w; approved regimen) for up to 4 years. Topical corticosteroids (TCS) and calcineurin inhibitors (TCI) were permitted. Exposure-adjusted incidence rates (number of patients with at least one event per 100 patient-years [nP/100 PY]) are reported.

RESULTS

Overall, 2677 patients were enrolled and treated with dupilumab: 352 (13.1%) completed up to week 204; 226 patients (8.4%) switched from qw to q2w during the trial. Rates of overall infections (71.27 nP/100 PY), serious and/or severe infections (1.39 nP/100 PY), and infections leading to discontinuation (0.34 nP/100 PY) were consistent with a previous 3-year analysis of this study and low compared with 1-year results in adults with AD treated with placebo + TCS. The cumulative number of patients with treatment-emergent serious or severe infections, non-herpetic or herpetic infections, and total skin infections decreased year-over-year. Limitations included open-label study design with no placebo arm; decreasing sample size at later time points due to sponsor decision to close sites following regulatory approval; qw dosing differs from approved q2w dosing; and patients could use TCS/TCI throughout the study, which may have impacted infection rates.

CONCLUSIONS

Continuous long-term dupilumab treatment in adults with moderate-to-severe AD is not associated with an increased risk of overall systemic or cutaneous infections.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01949311. Video Abstract INFOGRAPHIC.

Questionnaire-Based Study Evaluating the Hand Hygiene Practices and the Impact of Disinfection in the COVID-19 Pandemic on Hand Skin Conditions in Poland

During the COVID-19 pandemic, disinfection became an integral part of everybody's life in order to avoid spreading the coronavirus. In 2021, an original anonymous online survey was carried out. The questions concerned the usage of disinfectants. The study population included 56 subjects diagnosed by a physician with hand eczema (HE-derm group) and 114 subjects with no hand skin disease diagnosed by a specialist (non-derm). The HE and non-HE groups were distinguished. Nearly 80% of the HE group, and 10% of the non-HE group, experienced worsening of hand skin lesions caused by increased skin disinfection. HE-group respondents more often declared the occurrence of new hand skin symptoms, over 80% of the subjects of this group had more than 1 new symptom (compared to nearly 40% of the non-HE group). Exacerbations of the skin disease were more frequently observed by the HE group during the pandemic. There was a statistically significant decrease of the quality of life in the HE group compared to the non-HE group during the pandemic. The COVID-19 pandemic caused an increase in the prevalence of hand skin symptoms and deterioration of the skin condition. Education on appropriate disinfection techniques and skincare, as well as early dermatological intervention, might allow us to limit the development of hand skin diseases.

Genetic/Environmental Contributions and Immune Dysregulation in Children with Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin conditions in humans. AD affects up to 20% of children worldwide and results in morbidity for both patients and their caregivers. The basis of AD is an interplay between genetics and the environment characterized by immune dysregulation. A myriad of mutations that compromise the skin barrier and/or immune function have been linked to AD. Of these, filaggrin gene (FLG) mutations are the most evidenced. Many other mutations have been implicated in isolated studies that are often unreplicated, creating an archive of genes with potential but unconfirmed relevance to AD. Harnessing big data, polygenic risk scores (PRSs) and genome-wide association studies (GWAS) may provide a more practical strategy for identifying the genetic signatures of AD. Epigenetics may also play a role. Staphylococcus aureus is the most evidenced microbial contributor to AD. Cutaneous dysbiosis may result in over-colonization by pathogenic strains and aberrant skin immunity and inflammation. Aeroallergens, air pollution, and climate are other key environmental contributors to AD. The right climate and/or commensals may improve AD for some patients.

Novel Interactions of Myristic Acid and FADS3 Variants Predict Atopic Dermatitis among Indonesian Infants

Fatty acids exert a range of different biological activities that could be relevant in the development of atopic dermatitis (AD). This study investigated the association of glycerophospholipid fatty acids (GPL-FA) with AD, and their interactions with single nucleotide polymorphisms (SNP) of the FADS1-3 gene cluster. Among 390 infants of the Indonesian ISADI study, GPL-FA were measured in umbilical plasma (P-0y) and in buccal cells at birth (B-0y), and again in buccal cells at AD onset or one year (B-1y). Prospective and cross-sectional associations with AD were assessed by logistic regression. Interactions of GPL-FA with 14 SNP were tested assuming an additive model. AD was diagnosed in 15.4% of participants. In B-1y, C18:2n-6 was inversely associated with AD; and positive associations were observed for C18:1n-9, C20:4n-6, C22:6n-3 and C20:4n-6/C18:2n-6. There were no prospective associations with AD, however, a significant interaction between the SNP rs174449 and B-0y C14:0 (myristic acid) was observed. This study indicates that Indonesian infants with AD have increased rates of endogenous long-chain polyunsaturated fatty acid production, as well as higher C18:1n-9 levels. GPL-FA measured at birth do not predict later AD incidence; however, genotype interactions reveal novel effects of myristic acid, which are modified by a FADS3 variant.

European guideline (EuroGuiDerm) on atopic eczema - part II: non-systemic treatments and treatment recommendations for special AE patient populations

The evidence- and consensus-based guideline on atopic eczema was developed in accordance with the EuroGuiDerm Guideline and Consensus Statement Development Manual. Four consensus conferences were held between December 2020 and July 2021. Twenty-nine experts (including clinicians and patient representatives) from 12 European countries participated. This second part of the guideline includes recommendations and detailed information on basic therapy with emollients and moisturizers, topical anti-inflammatory treatment, antimicrobial and antipruritic treatment and UV phototherapy. Furthermore, this part of the guideline covers techniques for avoiding provocation factors, as well as dietary interventions, immunotherapy, complementary medicine and educational interventions for patients with atopic eczema and deals with occupational and psychodermatological aspects of the disease. It also contains guidance on treatment for paediatric and adolescent patients and pregnant or breastfeeding women, as well as considerations for patients who want to have a child. A chapter on the patient perspective is also provided. The first part of the guideline, published separately, contains recommendations and guidance on systemic treatment with conventional immunosuppressive drugs, biologics and janus kinase (JAK) inhibitors, as well as information on the scope and purpose of the guideline, and a section on guideline methodology.