Comparing the risk of death, major adverse cardiac events, and relapse in bullous pemphigoid patients treated with systemic or topical corticosteroids.

BACKGROUND: According to current guidelines, systemic or topical corticosteroids are recommended as first-line treatments for bullous pemphigoid (BP). There is evidence suggesting that topical application may be associated with a lower risk of mortality. However, there is a lack of comprehensive large-scale data comparing mortality rates, as well as the risk of major adverse cardiac events (MACE), infections, and relapse, between systemic and topical corticosteroid treatments. OBJECTIVES: To evaluate the risk of death, MACE, infections, and relapse in BP patients treated with systemic or topical corticosteroids. METHODS: A population-based retrospective cohort study was performed in the TriNetX US Collaborative Network. As a measure against bias, propensity-score matching for age, sex, ten diseases and six medications, and three sensitivity analyses were conducted. RESULTS: All-time risk of death was increased in US BP patients exposed to any dose of systemic corticosteroids (n=2,917) compared to topical clobetasol propionate treated patients (n=2,932, hazard ratio [HR], 1.43, 95% confidence interval [CI] 1.28-1.58, p<0.0001). This was consistent in time-stratified analysis (1- and 3-year mortality rates), and in analysis contrasting prednisone (equivalent) does of 1-10 mg (low) or 30-100 mg (medium-high) systemic corticosteroid to topical treatment. The increased risk of death in US BP patients exposed to any dose of systemic corticosteroids compared to topical treatment was accompanied by increased risks for MACE (HR 1.33, CI 1.08-1.64, p=0.0075) and infections (HR 1.33, CI 1.15-1.54, p=0.0001). The risk of continued disease or relapse was decreased in patients treated with systemic as opposed to topical corticosteroid (HR 0.85, CI 0.77-0.94, p=0.0016). Results regarding mortality and continued disease or relapse persisted in three of three sensitivity analyses. Potential limitations are the retrospective data collection, bias for treatment selection and miscoding. CONCLUSION: Pending validation in prospective studies, where feasible, and despite the heightened risk of relapse, topical corticosteroid treatment may be advantageous compared to systemic corticosteroid treatment due to its significantly lower risk of death.

Forward genetics and functional analysis highlight Itga11 as a modulator of murine psoriasiform dermatitis.

Psoriasis is a chronic inflammatory skin condition. Repeated epicutaneous application of Aldara® (imiquimod) cream results in psoriasiform dermatitis in mice. The Aldara®-induced psoriasiform dermatitis (AIPD) mouse model has been used to examine the pathogenesis of psoriasis. Here, we used a forward genetics approach in which we compared AIPD that developed in 13 different inbred mouse strains to identify genes and pathways that modulated disease severity. Among our primary results, we found that the severity of AIPD differed substantially between different strains of inbred mice and that these variations were associated with polymorphisms in Itga11. The Itga11 gene encodes the integrin α11 subunit that heterodimerizes with the integrin ß1 subunit to form integrin α11ß1. Less information is available about the function of ITGA11 in skin inflammation; however, a role in the regulation of cutaneous wound healing, specifically the development of dermal fibrosis, has been described. Experiments performed with Itga11 gene-deleted (Itga11-/- ) mice revealed that the integrin α11 subunit contributes substantially to the clinical phenotype as well as the histopathological and molecular findings associated with skin inflammation characteristic of AIPD. Although the skin transcriptomes of Itga11-/- and WT mice do not differ from one another under physiological conditions, distinct transcriptomes emerge in these strains in response to the induction of AIPD. Most of the differentially expressed genes contributed to extracellular matrix organization, immune system, and metabolism of lipids pathways. Consistent with these findings, we detected a reduced number of fibroblasts and inflammatory cells, including macrophages, T cells, and tissue-resident memory T cells in skin samples from Itga11-/- mice in response to AIPD induction. Collectively, our results reveal that Itga11 plays a critical role in promoting skin inflammation in AIPD and thus might be targeted for the development of novel therapeutics for psoriasiform skin conditions. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Transparent Exploration of Machine Learning for Biomarker Discovery from Proteomics and Omics Data.

Biomarkers are of central importance for assessing the health state and to guide medical interventions and their efficacy; still, they are lacking for most diseases. Mass spectrometry (MS)-based proteomics is a powerful technology for biomarker discovery but requires sophisticated bioinformatics to identify robust patterns. Machine learning (ML) has become a promising tool for this purpose. However, it is sometimes applied in an opaque manner and generally requires specialized knowledge. To enable easy access to ML for biomarker discovery without any programming or bioinformatics skills, we developed "OmicLearn" (http://OmicLearn.org), an open-source browser-based ML tool using the latest advances in the Python ML ecosystem. Data matrices from omics experiments are easily uploaded to an online or a locally installed web server. OmicLearn enables rapid exploration of the suitability of various ML algorithms for the experimental data sets. It fosters open science via transparent assessment of state-of-the-art algorithms in a standardized format for proteomics and other omics sciences.

Management and treatment outcome of DRESS patients in Europe: An international multicentre retrospective study of 141 cases.

BACKGROUND: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a rare but potentially fatal drug hypersensitivity reaction. OBJECTIVE: To explore treatment approaches across Europe and their impact on the disease course, as well as prognostic factors and culprit drugs. METHODS: In this retrospective European multicentric study, we included patients with probable or certain DRESS (RegiSCAR score ≥ 4) between January 2016 and December 2020. Independent associations between clinical parameters and the risk of intensive care unit admission and mortality at three months were assessed using a multivariable-adjusted logistic regression model. RESULTS: A total of 141 patients from 8 tertiary centres were included. Morbilliform exanthem was the most frequent cutaneous manifestation (78.0%). The mean affected body surface area (BSA) was 67%, 42% of the patients presented with erythroderma, and 24.8% had mucosal involvement. Based on systemic involvement, 31.9% of the patients had a severe DRESS. Anticonvulsants (24.1%) and sulphonamides (22.0%) were the most frequent causative agents. In all, 73% of the patients were treated with systemic glucocorticoids, and 25.5% received topical corticosteroids as monotherapy. Few patients received antiviral drugs or anti-IL5. No patients received intravenous immunoglobulins. The overall mortality was 7.1%. Independent predictors of mortality were older age (≥57.0 years; fully adjusted OR, 9.80; 95% CI, 1.20-79.93; p = 0.033), kidney involvement (fully adjusted OR, 4.70; 95% CI, 1.00-24.12; p = 0.049), and admission in intensive care unit (fully adjusted OR, 8.12; 95% CI, 1.90-34.67; p = 0.005). Relapse of DRESS and delayed autoimmune sequelae occurred in 8.5% and 12.1% of patients, respectively. CONCLUSIONS: This study underlines the need for diagnostic and prognostic scores/markers as well as for prospective clinical trials of drugs with the potential to reduce mortality and complications of DRESS.

S2k guidelines on the management of paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome initiated by the European Academy of Dermatology and Venereology (EADV).

BACKGROUND: Paraneoplastic pemphigus (PNP), also called paraneoplastic autoimmune multiorgan syndrome (PAMS), is a rare autoimmune disease with mucocutaneous and multi-organ involvement. PNP/PAMS is typically associated with lymphoproliferative or haematological malignancies, and less frequently with solid malignancies. The mortality rate of PNP/PAMS is elevated owing to the increased risk of severe infections and disease-associated complications, such as bronchiolitis obliterans. OBJECTIVES: These guidelines summarize evidence-based and expert-based recommendations (S2k level) for the clinical characterization, diagnosis and management of PNP/PAMS. They have been initiated by the Task Force Autoimmune Blistering Diseases of the European Academy of Dermatology and Venereology with the contribution of physicians from all relevant disciplines. The degree of consent among all task force members was included. RESULTS: Chronic severe mucositis and polymorphic skin lesions are clue clinical characteristics of PNP/PAMS. A complete assessment of the patient with suspected PNP/PAMS, requiring histopathological study and immunopathological investigations, including direct and indirect immunofluorescence, ELISA and, where available, immunoblotting/immunoprecipitation, is recommended to achieve a diagnosis of PNP/PAMS. Detection of anti-envoplakin antibodies and/or circulating antibodies binding to the rat bladder epithelium at indirect immunofluorescence is the most specific tool for the diagnosis of PNP/PAMS in a patient with compatible clinical and anamnestic features. Treatment of PNP/PAMS is highly challenging. Systemic steroids up to 1.5 mg/kg/day are recommended as first-line option. Rituximab is also recommended in patients with PNP/PAMS secondary to lymphoproliferative conditions but might also be considered in cases of PNP/PAMS associated with solid tumours. A multidisciplinary approach involving pneumologists, ophthalmologists and onco-haematologists is recommended for optimal management of the patients. CONCLUSIONS: These are the first European guidelines for the diagnosis and management of PNP/PAMS. Diagnostic criteria and therapeutic recommendations will require further validation by prospective studies.

Research in practice: Diet and microbiome in autoimmune diseases.

The incidence of autoimmune diseases in industrialized countries is constantly increasing over past decades. These diseases lead to increased mortality and persistent reduction in quality of life of the patients, posing a severe medical burden. Treatment of autoimmune diseases is often based on unspecific immune suppression, increasing the risk of infectious diseases as well as cancer manifestation. Pathogenesis of autoimmune conditions is complex and includes not only genetic factors, but also environmental influence, which is considered to be the reason for the rise of incidence of autoimmune diseases. Environmental factors comprise numerous elements, such as infections, smoking, medication, diet etc., which can either promote or prevent the onset of autoimmunity. However, the mechanisms of environmental influence are complex and for this moment not clearly understood. Deciphering of these interactions could enhance our comprehension of autoimmunity and provide some novel treatment options for the patients.

Impact of diet and genes on murine autoimmune pancreatitis.

The impact of environmental factors, such as diet, and the genetic basis of autoimmune pancreatitis (AIP) are largely unknown. Here, we used an experimental murine AIP model to identify the contribution of diet to AIP development, as well as to fine-map AIP-associated genes in outbred mice prone to develop the disease. For this purpose, we fed mice of an autoimmune-prone intercross line (AIL) three different diets (control, calorie-reduced and western diet) for 6 months, at which point the mice were genotyped and phenotyped for AIP. Overall, 269 out of 734 mice (36.6%) developed AIP with signs of parenchymal destruction, equally affecting mice of both sexes. AIP prevalence and severity were reduced by approximately 50% in mice held under caloric restriction compared to those fed control or western diet. We identified a quantitative trait locus (QTL) on chromosome 4 to be associated with AIP, which is located within a previously reported QTL. This association does not change when considering diet or sex as an additional variable for the mapping. Using whole-genome sequences of the AIL founder strains, we resolved this QTL to a single candidate gene, namely Map3k7. Expression of Map3k7 was largely restricted to islet cells as well as lymphocytes found in the exocrine pancreas of mice with AIP. Our studies suggest a major impact of diet on AIP. Furthermore, we identify Map3k7 as a novel susceptibility gene for experimental AIP. Both findings warrant clinical translation.

Serration pattern analysis for differentiating epidermolysis bullosa acquisita from other pemphigoid diseases.

BACKGROUND: Direct immunofluorescence (DIF) microscopy of a skin biopsy specimen is the reference standard for the diagnosis of pemphigoid diseases (PDs). Serration pattern analysis enables the differentiation of epidermolysis bullosa acquisita (EBA) from other PDs using DIF microscopy alone. However, practice gaps need to be addressed in order to implement this technique in the routine diagnostic procedure. OBJECTIVE: We sought to determine and optimize the technical requirements for serration pattern analysis of DIF microscopy and determine interrater conformity of serration pattern analysis. METHODS: We compared serration pattern analysis of routine DIF microscopy from laboratories in Groningen, The Netherlands and Lübeck, Germany with 4 blinded observers. Skin biopsy specimens from 20 patients with EBA and other PDs were exchanged and analyzed. Various factors were evaluated, including section thickness, transport medium, and biopsy specimen processing. RESULTS: The interrater conformity of our 4 observers was 95.7%. Recognition of serration patterns was comparable in samples transported in saline and in Michel's medium and with section thicknesses of 4, 6, and 8 µm. LIMITATIONS: Limitations include our small sample size and the availability of 20 samples that were compared retrospectively. CONCLUSION: DIF serration pattern analysis is not restricted by variation in laboratory procedures, transport medium, or experience of observers. This learnable technique can be implemented as a routine diagnostic method as an extension of DIF microscopy for subtyping PD.

Dissecting genetics of cutaneous miRNA in a mouse model of an autoimmune blistering disease.

BACKGROUND: MicroRNAs (miRNAs) are small endogenous non-coding RNAs that control genes at post-transcriptional level. They are essential for development and tissue differentiation, and such altered miRNA expression patterns are linked to the pathogenesis of inflammation and cancer. There is evidence that miRNA expression is genetically controlled similar to the transcription of protein-coding genes and previous studies identified quantitative trait loci (QTL) for miRNA expression in the liver. So far, little attention has been paid to miRNA expression in the skin. Moreover, epistatic control of miRNA expression remains unknown. In this study, we characterize genetic regulation of cutaneous miRNA and their correlation with skin inflammation using a previously established murine autoimmune-prone advanced intercross line. RESULTS: We identified in silico 42 eQTL controlling the expression of 38 cutaneous miRNAs and furthermore found two chromosomal hot-spots on chromosomes 2 and 8 that control the expression of multiple miRNAs. Moreover, for 8 miRNAs an interacting effect from pairs of SNPs was observed. Combining the constraints on genes from the statistical interaction of their loci and further using curated protein interaction networks, the number of candidate genes for association of miRNAs was reduced to a set of several genes. A cluster analysis identified miR-379 and miR-223 to be associated with EBA severity/onset, where miR-379 was observed to be associated to loci on chromosome 6. CONCLUSION: The murine advanced intercross line allowed us to identify the genetic loci regulating multiple miRNA in skin. The recurrence of trans-eQTL and epistasis suggest that cutaneous miRNAs are regulated by yet an unexplored complex gene networks. Further, using co-expression analysis of miRNA expression levels we showed that multiple miRNA contribute to multiple pathways that might be involved in pathogenesis of autoimmune skin blistering disease. Specifically, we provide evidence that miRNA such as miR-223 and miR-379 may play critical role in disease progression and severity.

Recombinant human IgA1 and IgA2 autoantibodies to type VII collagen induce subepidermal blistering ex vivo.

Subepidermal autoimmune blistering dermatoses (AIBD) are prototypic autoantibody-mediated diseases. In epidermolysis bullosa acquisita (EBA), an autoimmune disease with severe and chronic skin blistering, autoantibodies are directed against type VII collagen. IgG is the predominant autoantibody isotype of EBA, the pathogenicity of which has been demonstrated in a variety of in vivo and ex vivo disease models. In contrast, there is not much evidence for the pathogenicity of IgA, which may appear as the only autoantibody isotype in some EBA patients. To investigate the pathogenic potential of IgA autoantibodies, we generated chimeric V gene-matched human IgA1, IgA2, and control IgG1 autoantibodies directed against type VII collagen. Immobilized immune complexes containing the rIgA1 and rIgA2 autoantibodies induced the dose-dependent release of reactive oxygen species from neutrophil granulocytes, a precondition for blister formation. Moreover, both rIgA1 and rIgA2 induced leukocyte-dependent dermal-epidermal separation in cryosections of human skin. In contrast with rIgG1, neither rIgA1 nor rIgA2 was capable of inducing complement deposition at the dermal-epidermal junction. Because complement activation is a prerequisite for blister induction, this lack of function compared with IgG1 may be compensated for by the stronger activation of neutrophil granulocytes by both IgA1 and IgA2. For IgG-mediated AIBD, immunoadsorption therapy is a convenient treatment modality for the removal of pathogenic autoantibodies, particularly in treatment-resistant cases. The results of this study show the pathogenic potential of IgA autoantibodies and support the development of adsorber matrices for IgA-mediated AIBD.

B cells, dendritic cells, and macrophages are required to induce an autoreactive CD4 helper T cell response in experimental epidermolysis bullosa acquisita.

In autoimmune bullous dermatoses (AIBD), autoantibodies induce blisters on skin or mucous membranes, or both. Mechanisms of continued autoantibody production and blistering have been well characterized using AIBD animal models. Mechanisms leading to the initial autoantibody production, however, have not been investigated in detail. Epidermolysis bullosa acquisita (EBA) is an AIBD associated with autoantibodies to type VII collagen (COL7). The majority of EBA patients' sera recognize the noncollagenous domain 1, including the von Willebrand factor A-like domain 2 (vWFA2). In experimental EBA induced by immunization with GST-COL7, disease manifestation depended on the genetic background, a Th1 polarization, and the GST-tag. In this model, nude mice neither produced autoantibodies nor blisters. It has remained uncertain which APC and T cell subsets are required for EBA induction. We established a novel EBA model by immunization with vWFA2 fused to intein (lacking the GST-tag). All tested mouse strains developed autoantibodies, but blisters were exclusively observed in mice carrying H2s. In immunized mice, CD4 T cells specific for vWFA2 were detected, and their induction required presence of B cells, dendritic cells, and macrophages. Anti-vWFA2 autoantibodies located at the lamina densa bound to the dermal side of salt-split skin and induced blisters when transferred into healthy mice. Absence of CD8 T cells at time of immunization had no effect, whereas depletion of CD4 T cells during the same time period delayed autoantibody production and blisters. Collectively, we demonstrate the pathogenic relevance of Abs targeting the vWFA2 domain of COL7 and show the requirement of APC-induced CD4 T cells to induce experimental EBA.

Differential risks of psoriatic arthritis development in patients with varied psoriasis manifestations: a sex- and ethnicity-specific analysis.

Objectives: This study investigated psoriatic arthritis (PsA) risk across varied psoriasis manifestations, considering sex and ethnicity. Methods: Using TriNetX, a federated database encompassing over 120 million electronic health records (EHRs), we performed global retrospective cohort studies. Psoriasis vulgaris (Pso), pustulosis palmoplantaris (PPP), and generalized pustular psoriasis (GPP) cohorts were retrieved using ICD-10 codes. Propensity score matching, incorporating age, sex, and ethnicity, was employed. An alternative propensity matching model additionally included established PsA risk factors. Results: We retrieved data from 486 (Black or African American-stratified, GPP) to 35,281 (Pso) EHRs from the US Collaborative Network. Significant PsA risk variations emerged: Pso carried the highest risk [hazard ratio (HR) 87.7, confidence interval (CI) 63.4-121.1, p < 0.001], followed by GPP (HR 26.8, CI 6.5-110.1, p < 0.0001), and PPP (HR 15.3, CI 7.9-29.5, p < 0.0001). Moreover, we identified significant sex- and ethnicity-specific disparities in PsA development. For instance, compared to male Pso patients, female Pso patients had an elevated PsA risk (HR 1.1, CI 1.1-1.2, p = 0.002). Furthermore, White Pso patients had a higher likelihood of developing PsA compared to their Black or African American counterparts (HR 1.3, CI 1.04-1.7, p = 0.0244). We validated key findings using alternative propensity matching strategies and independent databases. Conclusion: This study delineates nuanced PsA risk profiles across psoriasis forms, highlighting the pivotal roles of sex and ethnicity. Integrating these factors into PsA risk assessments enables tailored monitoring and interventions, potentially impacting psoriasis patient care quality.

State-of-the-art diagnosis of autoimmune blistering diseases.

Autoimmune blistering disorders (AIBDs) are a heterogeneous group of approximately a dozen entities comprising pemphigus and pemphigoid disorders and dermatitis herpetiformis. The exact diagnosis of AIBDs is critical for both prognosis and treatment and is based on the clinical appearance combined with the detection of tissue-bound and circulating autoantibodies. While blisters and erosions on the skin and/or inspectable mucosal surfaces are typical, lesions may be highly variable with erythematous, urticarial, prurigo-like, or eczematous manifestations. While direct immunofluorescence microscopy (IFM) of a perilesional biopsy is still the diagnostic gold standard, the molecular identification of the major target antigens opened novel therapeutic avenues. At present, most AIBDs can be diagnosed by the detection of autoantigen-specific serum antibodies by enzyme-linked immunosorbent assay (ELISA) or indirect IFM when the clinical picture is known. This is achieved by easily available and highly specific and sensitive assays employing recombinant immunodominant fragments of the major target antigens, i.e., desmoglein 1 (for pemphigus foliaceus), desmoglein 3 (for pemphigus vulgaris), envoplakin (for paraneoplastic pemphigus), BP180/type XVII collagen (for bullous pemphigoid, pemphigoid gestationis, and mucous membrane pemphigoid), laminin 332 (for mucous membrane pemphigoid), laminin ß4 (for anti-p200 pemphigoid), type VII collagen (for epidermolysis bullosa acquisita and mucous membrane pemphigoid), and transglutaminase 3 (for dermatitis herpetiformis). Indirect IFM on tissue substrates and in-house ELISA and immunoblot tests are required to detect autoantibodies in some AIBD patients including those with linear IgA disease. Here, a straightforward modern approach to diagnosing AIBDs is presented including diagnostic criteria according to national and international guidelines supplemented by long-term in-house expertise.

Sensitive and specific assays for routine serological diagnosis of epidermolysis bullosa acquisita.

BACKGROUND: Epidermolysis bullosa acquisita (EBA) is a severe autoimmune subepidermal blistering disease characterized by autoantibodies against the N-terminal collagenous domain (NC1) of type VII collagen (Col VII). OBJECTIVE: Development of reliable assays for the detection of anti-Col VII-NC1 antibodies. METHODS: NC1 was expressed in human HEK293 cells and used as target antigen in an enzyme-linked immunosorbent assay (ELISA) and in an immunofluorescence assay (IFA). These two assays were probed in a large cohort of patients with EBA (n = 73), bullous pemphigoid (BP, n = 72), anti-p200 pemphigoid (n = 24), anti-laminin 332 mucous membrane pemphigoid (MMP, n = 15), pemphigus vulgaris (PV, n = 24), and healthy control subjects (n = 254). RESULTS: The cut-off for the ELISA was optimized for accuracy by receiver-operating characteristics (area under the curve [AUC] = 0.9952). IgG reactivity against NC1 was detected in 69 of 73 EBA (94.5%) and 5 control sera (2 healthy controls and 3 BP patients), resulting in a specificity of 98.7%. The IFA showed a sensitivity of 91.8% and specificity of 99.8%. Reproducibility of the ELISA was demonstrated by an intra-class correlation coefficient of 0.97. IgG subclass analyses by ELISA revealed IgG1, IgG2, IgG3, and IgG4 anti-NC1 reactivity in 83.6%, 85.3%, 37.7%, and 83.6% of EBA sera, respectively. LIMITATIONS: The novel assays were not evaluated prospectively and their use in monitoring serum levels during the disease course was not tested. CONCLUSION: The two assays are highly specific and sensitive to diagnose EBA. Their diagnostic competence was demonstrated in a large cohort of well-characterized EBA sera.

Morphea: The 2023 update.

Morphea, also known as localized scleroderma, is a chronic inflammatory connective tissue disorder with variable clinical presentations, that affects both adults and children. It is characterized by inflammation and fibrosis of the skin and underlying soft tissue, in certain cases even of the surrounding structures such as fascia, muscle, bone and central nervous system. While the etiology is still unknown, many factors may contribute to disease development, including genetic predisposition, vascular dysregulation, TH1/TH2 imbalance with chemokines and cytokines associated with interferon-γ and profibrotic pathways as well as certain environmental factors. Since the disease may progress to permanent cosmetic and functional sequelae, it is crucial to properly assess the disease activity and to initiate promptly the adequate treatment, thus preventing subsequent damage. The mainstay of treatment is based on corticosteroids and methotrexate. These, however, are limited by their toxicity, especially if applied long-term. Furthermore, corticosteroids and methotrexate often do not sufficiently control the disease and/or the frequent relapses of morphea. This review presents the current understanding of morphea by discussing its epidemiology, diagnosis, management and prognosis. In addition, it will describe recent pathogenetic findings, thus proposing potential novel targets for therapeutic development in morphea.