Atopic Eczema: Pathophysiological Findings as the Beginning of a New Era of Therapeutic Options

Obesity is linked to disease severity in moderate to severe atopic dermatitis-Data from the prospective observational TREATgermany registry

BACKGROUND

There are conflicting data on a potential association between obesity and atopic dermatitis (AD). The purpose of this study was to investigate the relationship between obesity and AD disease severity.

METHODS

Patients from the TREATgermany registry cohort were divided into three groups according to their body mass index (BMI). Due to low numbers, underweight patients (BMI <18.5 kg/m2) were excluded from the analysis. Physician- and patient-reported disease severity scores as well as additional phenotypic characteristics were evaluated for association with BMI. Generalized linear mixed models and multinomial logit models, respectively, were applied to investigate the association of BMI, age, sex and current systemic AD treatment with disease severity.

RESULTS

This study encompassed 1416 patients, of which 234 (16.5%) were obese (BMI ≥30 kg/m2). Obesity was associated with lower educational background and smoking. Otherwise, obese and non-obese AD patients had similar baseline characteristics. Increased BMI was associated with higher oSCORAD (adjusted β: 1.24, 95% CI: 1.05-1.46, p = 0.013) and Patient-oriented eczema measure (POEM) (adjusted β: 1.09, 95% CI: 1.01-1.17, p = 0.038). However, the absolute difference in the overall oSCORAD was small between obese and non-obese AD patients (Δ oSCORAD = 2.5). Allergic comorbidity was comparable between all three groups, with the exception of asthma which was more pronounced in obese patients (p < 0.001).

DISCUSSION

In this large and well-characterized AD patient cohort, obesity is significantly associated with physician- and patient-assessed measures of AD disease severity. However, the corresponding effect sizes were low and of questionable clinical relevance. The overall prevalence of obesity among the German AD patients was lower than in studies on other AD cohorts from different countries, which confirms previous research on the German population and suggests regional differences in the interdependence of AD and obesity prevalence.

Histamine and Th2 cytokines independently and synergistically upregulate MMP12 expression in human M2 macrophages

Beyond Th2 cells and various immune cells, M2 macrophages have been identified in lesional skin of atopic dermatitis (AD) indicating their involvement in the disease's underlying mechanisms. MMP12, a matrix-degrading enzyme, which is predominantly produced by macrophages, is increased in skin lesions of AD patients. In this study we investigated the expression of MMP12 mRNA in lesional AD skin at single cell level through RNA sequencing (scRNA-seq) and the expression of MMP12 in M2 macrophages from healthy individuals and AD patients in response to Th2 cytokines and histamine using quantitative PCR and ELISA. Additionally, we analyzed macrophages from dupilumab-treated AD patients using the same methods to assess the influence of Th2 cytokines on MMP12 expression ex-vivo. ScRNA-seq identified macrophages as the primary producers of MMP12 in lesional AD skin. In-vitro, both MMP12 mRNA and protein expression were significantly increased in monocytes during differentiation to M2 macrophages in the presence of histamine, of Th2 cytokines or of Th2 cytokines in combination with histamine. In M2 macrophages obtained from dupilumab-treated AD patients, the upregulation of MMP12 expression by IL-4 and IL-13 was attenuated. Our findings unveil a novel mechanism whereby Th2 cytokines and histamine regulate MMP12 expression, potentially impacting skin barrier homeostasis in AD.

High recurrence rate of eczema herpeticum in moderate/severe atopic dermatitis -TREATgermany registry analysis

BACKGROUND

Eczema herpeticum (EH) is a disseminated skin infection caused by herpes simplex virus in atopic dermatitis (AD) patients. The frequency of EH and the clinical features of EH patients have not yet been investigated in a larger cohort.

METHODS

We sought to investigate the TREATgermany cohort, a multicenter, non-interventional clinical registry of moderately to severely affected AD patients in Germany. Baseline characteristics of patients included between December 2017 and April 2021 were compared between patients without, single, and multiple EH.

RESULTS

Of the 893 patients, 195 (21.8%) had at least one EH. Of the 195 patients with EH, 107 had multiple EH (54.9%), representing 12.0% of the total study population. While there were no differences in demographic characteristics, previous treatment, and disease scores at enrollment (itch, IGA, oSCORAD, EASI), patients with EH had more frequent atopic comorbidities and sensitizations to house dust mite, food, and mold.

DISCUSSION

TREATgermany registry data suggest a high prevalence and recurrence rate of EH, while there appears to be no specific clinical phenotype, besides an increase in allergies, to identify EH patients in the daily routine.

Hohe Rezidivrate des Eczema herpeticatum bei mittelschwerer bis schwerer atopischer Dermatitis - eine TREATgermany Registeranalyse

Hintergrund

Das Eczema herpeticatum (EH) ist eine disseminierte Hautinfektion, die durch Herpes‐simplex‐Viren bei Patienten mit atopischer Dermatitis (AD) verursacht wird. Die Häufigkeit des EH und die klinischen Charakteristika von EH Patienten wurden bisher noch nicht in einer größeren Kohorte untersucht.

Methodik

87 Patienten des TREATgermany Registers, einem multizentrischen, nichtinterventionellen klinischen Register mit moderat bis schwer betroffenen AD‐Patienten in Deutschland, wurden in dieser Analyse betrachtet. Patienten, die zwischen Dezember 2017 und April 2021 in das Register eingeschlossen wurden, wurden unterteilt in die Gruppen ohne, mit einem und mit mehreren EH und basierend auf den klinischen Charakteristika verglichen.

Ergebnisse

Von 893 Patienten berichteten 195 (21,8%) über mindestens eine EH. 107 der 195 Patienten mit EH hatten sogar mehrere EH in der Anamnese (54,9%), was 12,0% der gesamten Studienpopulation entspricht. Während hinsichtlich demographischer Merkmale, Vorbehandlungen und Krankheitsscores (Juckreiz, IGA, oSCORAD, EASI) keine Unterschiede festgestellt wurden, litten Patienten mit EH häufiger an atopischen Begleiterkrankungen und Sensibilisierungen gegen Hausstaubmilben, Nahrungsmittel und Schimmelpilze.

Schlussfolgerungen

Die Daten des TREATgermany‐Registers deuten auf eine hohe Prävalenz und Rezidivrate des EH hin, während es neben einer Häufung von Allergien keinen spezifischen klinischen Phänotyp zu geben scheint, um EH‐Patienten in der täglichen Routine zu identifizieren.

Dupilumab strengthens herpes simplex virus type 1-specific immune responses in atopic dermatitis

BACKGROUND

Impaired virus clearance in a subgroup of atopic dermatitis (AD) patients can lead to severe herpes simplex virus (HSV) infections called eczema herpeticum (EH). We recently identified a type 2 skewed viral immune response in EH patients. Clinical data suggest a reduced incidence of EH in AD patients treated with dupilumab, although immunologic investigations of this phenomenon are still lacking.

OBJECTIVE

We examined the impact of dupilumab on the HSV type 1 (HSV-1) specific immune response in AD, focusing on patients with (ADEH+) and without (ADEH-) a history of EH.

METHODS

Sera and peripheral blood mononuclear cells were collected from ADEH+ and ADEH- patients, a subgroup of whom was receiving dupilumab treatment, and healthy controls. Serum samples were tested for IgE against HSV-1 glycoprotein D (n = 85). Peripheral blood mononuclear cells were stimulated with HSV peptides, and activated CD4+ and CD8+ cells were characterized by flow cytometry after magnetic enrichment via CD154 or CD137 (n = 60). Cytokine production of HSV-1-reactive T-cell lines (n = 33) and MHC-I tetramer+ (HSV-1-UL25) CD8+ T cells was investigated by bead assay and intracellular cytokine staining (n = 21).

RESULTS

We confirmed that HSV-1-specific IgE is elevated in ADEH+ patients. During dupilumab treatment, the IgE levels were significantly decreased, reaching levels of healthy controls. HSV-1-specific TC1 frequencies were elevated in ADEH- patients treated with dupilumab compared to dupilumab-negative patients. There were no changes in the frequencies of HSV-1-specific TH cells while receiving dupilumab therapy. AD patients receiving dupilumab exhibited elevated IFN-γ and reduced IL-4 production in HSV-1-UL25-epitope-specific T cells compared to dupilumab-negative patients.

CONCLUSION

Dupilumab may improve the HSV-1-specific immune response in AD as a result of an increased type I immune response and a reduction of HSV-1-specific IgE.

Real-World Experience with Tralokinumab in a Patient with Recalcitrant Atopic Dermatitis: A Case Report

Atopic dermatitis (AD) is a common inflammatory skin disease, which negatively impacts the individual's quality of life (QoL). In particular, moderate-to-severe AD is frequently difficult to treat. We report a case involving a 40-year-old male who has suffered from AD since early childhood and who also had co-morbid seasonal allergic rhinitis. In June 2021, we initiated treatment with the fully human IgG4 monoclonal antibody tralokinumab that specifically targets IL-13 and the patient has been followed for 38 weeks. During this time period, he received a booster vaccination for COVID-19 (week 18) and developed the disease in April 2022 (both with minimal impact). Tralokinumab treatment reduced AD symptoms, was well tolerated and improved QoL scores, and the patient reported that he was very satisfied with the treatment.

[Development of new topical substances for the treatment of atopic dermatitis]

Atopic dermatitis (AD) is one of the most common chronic inflammatory skin diseases. In everyday clinical practice, about 80% of patients present with mild to moderate disease, which is usually treated with topical therapy. Topical anti-inflammatory therapy thus continues to be the standard of care in addition to the basic therapy. Topical glucocorticoids (TGC) and topical calcineurin inhibitors (TCI) are two potent approved substances that are available. In addition to newly developed systemic therapies for moderate to severe AD, there are also new therapeutic approaches in anti-inflammatory topical treatment. Topical Janus kinase inhibitors show a high therapeutic effect. However, only delgocitinib and ruxolitinib have so far been approved for topical administration in Japan and the USA since 2021. Crisaborole, a phosphodiesterase 4 inhibitor, also received approval in the USA. Other phosphodiesterase inhibitors are currently being investigated in clinical trials. Interesting results of clinical studies give hope for further substances and therapeutic approaches.

[Modern systemic therapies for atopic dermatitis : Which factors determine the choice of therapy?]

For the treatment of moderate to severe atopic dermatitis (AD), two groups of modern systemic therapies with a total of five drugs are currently approved in Germany: biologics (dupilumab, tralokinumab) and "small molecules" (abrocitinib, baricitinib, upadacitinib). The growing armamentarium of therapy options, especially with more than one drug per substance group, makes it challenging for practitioners to select the appropriate treatment for the individual patient. In this review article, the preconditions and requirements of each drug group as well as the corresponding substances are presented comparatively. On the one hand, direct therapeutic effects on the severity of the disease are considered and, on the other hand, the spectrum of potential adverse drug reactions are discussed. In particular, short- and long-term effects, the safety profile and the patient's concomitant diseases represent key factors for shared decision-making with regard to select the optimum personalized therapy option.

The impact of the first COVID-19 wave on office-based dermatological care in Germany: a focus on diagnosis, therapy and prescription of biologics

Background

The COVID-19 pandemic has led to widespread changes in medical care. However, it is still unclear to what extent the care of patients suffering from moderate-to-severe psoriasis, chronic spontaneous urticaria or atopic dermatitis has been affected.

Objectives

This study was conducted to determine the impact of the SARS-CoV-2 pandemic on medical care in dermatological practices, focusing on physicians’ concerns related to susceptibility to infections in combination with different treatment modalities.

Materials & Methods

Dermatologists working in medical offices in the German federal states of Bavaria and Lower Saxony participated in a cross-sectional, non-interventional, questionnaire-based study investigating the influence of COVID-19 on dermatological care. The study was performed after the first wave of the coronavirus pandemic in July/August, 2020.

Results

A total of 195 dermatologists participated in the study. Almost one in five practices were closed for at least one week during the pandemic. The care of patients with chronic inflammatory skin diseases was impaired, affecting diagnostic investigation. Physicians stated that the pandemic substantially influenced systemic therapy. Nearly half of physicians surveyed were concerned about increased susceptibility to infections under biological therapy. No significant differences were identified between the German federal states of Bavaria and Lower Saxony in the south and north of Germany, respectively.

Conclusion

This study reveals a significant impact of the COVID-19 pandemic on the care of dermatological patients in medical offices in Germany. New management modalities and continuous education are needed to improve care in pandemic situations.

[Allergen immunotherapy for atopic dermatitis]

Seit dem ersten Bericht über die Allergenimmuntherapie (AIT) durch Noon et al. vor 110 Jahren wurden zahlreiche klinische und grundlagenwissenschaftliche Studien durchgeführt, um die Effekte der einzigen kurativen Behandlung von Allergien zu untersuchen. Bei der atopischen Dermatitis (AD) findet sie jedoch nur selten Anwendung, obwohl es Evidenz dafür gibt, dass Aeroallergene zu Exazerbationen der Erkrankung beitragen können. Dieser Übersichtsbeitrag umfasst die aktuelle Studienlage, Metaanalysen und Leitlinienempfehlungen zur AIT bei AD-Patienten. Es zeigt sich eine große Heterogenität hinsichtlich Studiendesigns, Patientenkohorten, Allergenen, Applikationsformen und Endpunkten, wodurch die Vergleichbarkeit der Studien erschwert wird. Mehrere Untersuchungen zeigen eine positive Wirkung der AIT auf den Schweregrad der AD, was darauf hindeutet, dass zumindest eine Untergruppe von Patienten von der Behandlung profitieren kann. Weitere Entwicklungen auf dem Gebiet der AIT könnten dazu beitragen, dass die Therapie einen breiteren Einsatz bei AD-Patienten findet.