Pemphigus

The application of direct immunofluorescence in the pathological diagnosis of oral mucosal diseases: Series of 116 cases

This study evaluated the diagnostic utility of direct immunofluorescence (DIF) in 116 oral mucosal bullous and atrophic lesions from Zhejiang University Stomatology Hospital (2022-2024). DIF and H&E analyses were performed on serial sections of the same biopsy specimens. Among the cases, 45 were diagnosed with pemphigus vulgaris, in which DIF revealed a reticular pattern of IgG (84.44 %) and C3 (73.33 %) deposition within the epithelial prickle cell layer. Benign mucous membrane pemphigoid was identified in 23 cases, characterized by linear deposits of IgG (56.52 %) and C3 (73.91 %) along the basement membrane zone (BMZ), with occasional expression of IgA (34.78 %) and IgM (17.39 %). In 14 cases of oral lichen planus, DIF demonstrated positive fibrinogen deposition in the BMZ (57.14 %), while IgA, IgG, IgM, and C3 were either weakly expressed or absent. 4 cases of chronic discoid lupus erythematosus exhibited granular deposits of IgG (100 %), sometimes accompanied by IgA, IgM, C3, and fibrinogen in the BMZ and perivascular. One case of linear IgA bullous dermatosis showed exclusive linear IgA deposition in the BMZ, with no detectable IgG, IgM, C3, or fibrinogen. DIF demonstrates significant clinical value in the diagnosis of atrophic and bullous lesions, particularly in pemphigus and lichen planus. The combination of IgG, C3 and fibrinogen may be economical and effective approach.

Non coding RNA biomarkers in pemphigus disease

Pemphigus represents a group of potentially life-threatening autoimmune blistering diseases characterized by the production of pathogenic autoantibodies against desmosomal cadherins, leading to loss of cell adhesion. Early and accurate diagnosis remains critical for optimal management, yet current diagnostic approaches largely rely on invasive biopsies and serological assays that do not always predict disease progression or therapeutic response. In this context, the identification of reliable biomarkers is essential to enhance diagnostic precision, monitor disease activity, and guide treatment strategies. Non-coding RNAs (ncRNAs), particularly microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), have emerged as promising biomarker candidates due to their stability in body fluids, tissue- and disease-specific expression patterns, and regulatory functions in immune processes. Increasing evidence suggests that dysregulated ncRNAs play significant roles in the immunopathogenesis of pemphigus, influencing cytokine signaling, immune cell differentiation, and keratinocyte adhesion. Therefore, herein, we summarize current findings on the involvement of specific miRNAs and lncRNAs in pemphigus pathogenesis, their diagnostic and prognostic potential, and the emerging therapeutic opportunities based on modulating ncRNA expression. Additionally, we address the limitations and challenges associated with clinical translation of ncRNA research and highlight future directions that may facilitate the incorporation of ncRNAs into personalized medicine approaches for pemphigus patients.

Epac1 contributes to apremilast-mediated rescue of pemphigus autoantibody-induced loss of keratinocyte adhesion

In the bullous autoimmune disease pemphigus vulgaris (PV), autoantibodies directed mainly against desmoglein 1 (Dsg1) and Dsg3 cause loss of desmosomal adhesion. We recently showed that intracellular cAMP increase by the phosphodiesterase 4 inhibitor apremilast was protective in different PV models. Thus, we here analyzed the involvement of the cAMP effector exchange factor directly activated by cAMP1 (Epac1). In Epac1-deficient mice pemphigus antibody-induced blistering was ameliorated in vivo while apremilast had no additional effect. Interestingly, augmented protein levels of Dsg1 and Dsg3 as well as increased Dsg1 mRNA levels and higher numbers of Dsg1- and Dsg3-dependent single-molecule interactions were detected in keratinocytes derived from Epac1-deficient mice. This was paralleled by stronger intercellular adhesion under baseline conditions and prevention of pemphigus autoantibody-induced loss of intercellular adhesion. However, the protective effect of apremilast against loss of intercellular adhesion in response to the pathogenic Dsg3 antibody AK23 was attenuated in Epac1-deficient keratinocytes. Similarly, the Epac1 inhibitor Esi09 protected keratinocytes from pemphigus antibody-induced loss of adhesion. Mechanistically, Epac1 deficiency resulted in lack of apremilast-induced Rap1 activation and phosphorylation of Pg at S665. Taken together, these data indicate that Epac1 is involved in the regulation of baseline and cAMP-mediated stabilization of keratinocyte adhesion.

Prevalence and pathogenic activity of anti-desmocollin-3 antibodies in patients with pemphigus vulgaris and pemphigus foliaceus

BACKGROUND

Desmocollin-3 (DSC3) is a calcium-dependent desmosomal cadherin that plays an essential role in cell-cell adhesion. IgG antibodies (Abs) directed against the extracellular (EC) domain of DSC3 have occasionally been detected in rare types of pemphigus. Investigations into the prevalence of anti-EC-DSC3 IgG Abs and those targeting the intracellular (IC) domain of DSC3 in pemphigus vulgaris and pemphigus foliaceus sera, and their potential pathogenic activity, have yielded conflicting results.

OBJECTIVES

To assess the prevalence and pathogenicity of Abs directed against the EC and IC domains of DSC3 in patients with pemphigus.

METHODS

Anti-DSC3 IgG and IgA directed against the EC and IC domains of DSC3 were assayed in 146 patients with pemphigus using a newly developed addressable laser bead immunoassay. The pathogenicity of these autoAbs was first tested in vitro using a keratinocyte dissociation assay with patients' sera or from C57BL/6 mice immunized with recombinant IC-DSC3. In vivo pathogenicity was tested by passive transfer of an anti-IC-DSC3 monoclonal Ab (mAb) derived from a hybridoma (A9) into neonatal mice.

RESULTS

Anti-EC-DSC3 or anti-IC-DSC3 IgG and/or IgA Abs were detected in 21.2% of sera from patients with pemphigus vs. 4.0% (P < 0.001) and 5.0% (P < 0.001) of sera from healthy donors, respectively. Most anti-DSC3 Abs corresponded to IgA. Anti-IC-DSC3 Abs were detected in 44% of patients with pemphigus whose serum anti-desmoglein (DSG) 1-3 Ab profile was inconsistent with their clinical and histological features, according to compensation theory. Anti-IC-DSC3 IgG and IgA Abs induced a dissociation of the keratinocyte monolayer in vitro, which was abolished by preadsorption of these IgG or IgA fractions with recombinant IC-DSC3. In addition, IgG from mice immunized with recombinant IC-DSC3 induced acantholysis in vitro. Finally, in neonatal mice, the passive transfer of an anti-IC-DSC3 mAb in combination with anti-DSG1-3 Abs exacerbated blister formation.

CONCLUSIONS

Our findings suggest that anti-IC-DSC3 Abs are pathogenic and explain the discordance seen in some patients with regard to their clinical phenotype and their anti-DSG1-3 Ab profile.

High-Sensitivity Cell-Based Plasmonic Biolayer Interferometry with a Two-Tiered Enhancement for Clinical Autoimmunity Surveillance of Pemphigus Vulgaris

Pemphigus vulgaris (PV) is a chronic, often fatal autoimmune blistering disorder that affects the skin and body-wide mucous membranes, imperatively urging for accurate detection of characteristic autoantibodies. To overcome the sensitivity constraint, we report here a serological avidity test for complex PV autoantibodies, relying on cell-based plasmonic biolayer interferometry (cpBLI) with two-tiered enhancement of light interference by gold nanostars (AuNSs). High-surface-area, clean-surface AuNSs with abundant tips and grooves can enhance interference patterns and promote intrinsic and extrinsic catalysis of 3,3'-diaminobenzidine by themselves and conjugated peroxidase, enabling a dual hierarchical signal amplification of 26.8-fold over conventional BLI at a limit of detection of 0.36 pM. The cpBLI responses correlate well with diagnostic ELISA from clinical laboratories, precisely differentiating PV from normal and other epithelial antibody-associated immunobullous cutaneous diseases such as bullous pemphigoid. In a simple dip-and-read format with real-time readouts, the efficacy was verified in a masked validation cohort and multicenter patient samples. The cpBLI effectively assesses PV prognosis and precisely stratifies severity in good association with the Pemphigus Disease Area Index (PDAI). Notably, live cells on the biosensor surface facilitate drug screening by responding to PV therapeutics. Therefore, the cpBLI immunodiagnostic assay is promising for diagnosing, staging, and therapeutic monitoring PV in clinical settings and can be generalized for other autoimmune diseases.

Factors associated with persistent anti-desmoglein positivity after remission in pemphigus vulgaris: a prospective registry-based cohort study

Introduction

Anti-desmoglein (Dsg) antibodies are well-established markers correlated with clinical phenotype and disease severity in pemphigus vulgaris (PV). However, elevated anti-Dsg antibody levels have been observed in some patients during clinical remission (CR). This study aimed to identify clinical characteristics and risk factors in PV patients with elevated anti-Dsg antibodies after achieving CR.

Methods

We conducted a cohort study based on the prospective registry database of autoimmune bullous diseases patients at West China Hospital between April 2016 and March 2022. PV patients with at least 12 months of follow-up were enrolled. The pemphigus disease area index (PDAI) and anti-Dsg antibody titers were measured at baseline and 1, 3, 6, 9, 12 months during follow-up. Univariate, multivariate analyses and receiver operating characteristics (ROC) curves were performed to identify associated factors with persistent antibody positivity and optimal cut-off values respectively. The primary outcome was the persistent positivity of antibodies against Dsg after achieving CR.

Results

Among 239 PV patients enrolled in this study, 118 (49%) achieved CR. Cataracts were identified as an independent risk factor for persistent anti-Dsg1 positivity after CR. Higher baseline anti-Dsg3 antibody titers and PDAI scores were significant predictors of increased anti-Dsg3 levels post-CR, with gender also being a contributing factor. ROC analysis determined a cut-off value of 157.4 U/mL for anti-Dsg3 with 56.3% sensitivity and 82.6% specificity.

Conclusion

The presence of Cataracts may indicate persistent anti-Dsg1 positivity after CR, while elevated anti-Dsg3 titers and PDAI scores at baseline may predict sustained elevated anti-Dsg3 post-CR.

MicroRNAs in patients with pemphigus: A systematic review

BACKGROUND

Pemphigus is a group of rare and severe autoimmune blistering diseases (AIBDs). MicroRNA's role in the pathogenesis of pemphigus disease has been previously studied, but MicroRNAmicroRNAs research in dermatology is still at its beginning.

METHODS

This review was carried out using a systematic search on PubMed, Scopus Embase, and Web of Science from 1990 to February 2025 to explore the role of microRNA in the diagnosis and severity evaluation of pemphigus disease.

RESULTS

A total of 8 studies were identified in the systematic review that indicated the expression level of 18 types of microRNA was significantly different from that of healthy people.

CONCLUSIONS

The collective data presented in this review indicate that MicroRNAmicroRNAs may help diagnose and predict the course of pemphigus, while the clinical application of these findings has yet to be verified.

Autoimmune Bullous Disease Combined With Acquired Hemophilia A: A Systematic Review and Case Analysis

Autoimmune bullous diseases (AIBDs) are rare, chronic conditions characterized by blisters and erosions on the skin and mucous membranes. Acquired hemophilia A (AHA) is a rare bleeding disorder in which autoantibodies target coagulation factor VIII, often associated with other autoimmune diseases. However, the simultaneous occurrence of AIBD and AHA is rare, with limited understanding of their combined impacts. We aimed to synthesize the available evidence and provide insights into clinical manifestations, treatment strategies, and survival outcomes of such patients. We searched for relevant literature in four databases: PubMed, Web of Science, EMBASE, and Scopus, and combined patient information from our hospital to provide a comprehensive analysis. A total of 80 patients were included. Through log-rank tests, older age (p = 0.03) and bullous pemphigoid (BP) (p = 0.047) were associated with shorter survival time. In the multivariate Cox proportional hazards regression model, mortality was only associated with older age (HR: 1.13, p = 0.02). Patients presenting both AIBD and AHA exhibit intricate clinical presentations and are at risk of severe, potentially fatal outcomes. Clinicians should remain vigilant regarding bleeding in AIBD patients, particularly those with BP and those in the geriatric population.

Meeting Report on "10th Anniversary Symposium on Inflammatory Skin Disease"

The Lübeck Institute of Experimental Dermatology celebrated its 10th Anniversary Symposium on Inflammatory Skin Diseases at the University of Lübeck, Germany, on October 17-18, 2024. This event brought together international key opinion leaders, faculty members, researchers, and clinicians to foster insightful discussions on the diagnosis, pathomechanisms, and treatment of autoimmune skin diseases, with a particular focus on pemphigus, pemphigoid diseases, and systemic sclerosis.

Shared Phenotypes of Immune Cells Recruited to the Cornea and the Surface of the Lens in Response to Formation of Corneal Erosions

Injuries to the cornea can lead to recurrent corneal erosions, compromising its barrier function and increasing the risk of infection. Vital as corneal integrity is to the eye's optical power and homeostasis, the immune response to corneal erosions remains poorly understood. It is also unknown whether there is coordinated immune activation between the cornea and other regions of the anterior segment to protect against microbial invasion and limit the spread of inflammation when corneal erosions occur. Herein, a corneal debridement wounding model was used to characterize the immune cell phenotypes populating the cornea in response to erosion formation, and whether and which immune cells are concurrently recruited to the surface of the lens was investigated. The formation of corneal erosions induced an influx of myeloid lineage phenotypes, both M2 macrophages associated with tissue healing and wound repair, and Ly6G+ Ly6C+ myeloperoxidase+ cells resembling neutrophils/polymorphonuclear-myeloid-derived suppressor cells (PMN-MDSCs), with few regulatory T cells, into the corneal stroma under erosion sites. This leukocyte migration into the cornea when erosions develop was paralleled by the recruitment of immune cells, predominantly neutrophils/PMN-MDSCs, to the anterior, cornea-facing lens capsule. Both cornea-infiltrating and lens capsule-associated neutrophil/PMN-MDSC-like immune cells produce the anti-inflammatory cytokine IL-10. These findings suggest a collaborative role for the lens capsule-associated immune cells in preventing infections, controlling inflammation, and maintaining homeostasis of the anterior segment during recurrent corneal erosions.

Exploring telitacicept in a patient with pemphigus vulgaris

Our case demonstrates significant improvement in autoantibody levels and clinical outcomes, suggesting that telitacicept could be an alternative treatment for patients with mild pemphigus [Pemphigus Disease Area Index (PDAI) ＞9] who are not recommended for treatment with rituximab (PDAI ＜15), and especially for those unresponsive to conventional treatments or with treatment-resistant scalp lesions in pemphigus.

Molecular Hydrogen Ameliorates Anti-Desmoglein 1 Antibody-Induced Pemphigus-Associated Interstitial Lung Disease by Inhibiting Oxidative Stress

Pemphigus-associated interstitial lung disease (P-ILD) is a severe complication observed in pemphigus patients that is characterized by pulmonary interstitial inflammation and fibrosis. This study investigated the role of anti-desmoglein (Dsg) 1/3 antibodies in P-ILD pathogenesis and evaluated the therapeutic potential of molecular hydrogen (H2). Using a BALB/cJGpt mouse model, we demonstrated that anti-Dsg 1 antibodies, but not anti-Dsg 3 antibodies, induced interstitial inflammation and fibrosis. Immunofluorescence staining confirmed IgG deposition in the alveolar epithelium, suggesting immune complex formation and epithelial damage. Gene expression analysis revealed elevated pro-inflammatory cytokines (IL-1β, IL-13) and upregulated pro-fibrotic markers (α-SMA, S100A4, TGF-β, and collagen genes) in P-ILD progression. Elevated oxidative stress and impaired ROS metabolism further implied the role of oxidative damage in disease pathogenesis. To assess H2's therapeutic potential, hydrogen-rich water was administered to P-ILD mice. H2 treatment significantly reduced oxidative stress, attenuated interstitial inflammation, and prevented pulmonary fibrosis. These protective effects were attributed to H2's antioxidant properties, which restored the pro-oxidant-antioxidant balance. Our findings underscore the critical role of anti-Dsg 1 antibodies and oxidative stress in P-ILD and highlight H2 as a promising therapeutic agent for mitigating anti-Dsg 1 antibody-induced lung injury.

Severe psoriasis vulgaris complicating pemphigus vulgaris: A case report

RATIONALE

Currently, the main comorbidities of psoriasis are cardiovascular, metabolic, liver and kidney, autoimmune, and psychological disorders. Psoriasis associated with pemphigus is relatively rare. This rare disease presents with significant clinical, diagnostic, and therapeutic challenges.

PATIENT CONCERNS

The patient was a 71-year-old man with recurrent erythema, papules, and scales with itching all over the body for 11 years, accompanied by blisters and erosions for more than 1 month, and aggravated by generalized eruption for 1 week. The patient was diagnosed with pemphigus vulgaris and admitted to our hospital with intravenous methylprednisolone combined with a conventional oral antihistamine and topical hormonal ointment. The patient's symptoms significantly disappeared. The patient complained that his condition recurred easily after discontinuing medication, which seriously affected his daily life and sleep. The patient also had essential hypertension, nail psoriasis, tinea pedis, and onychomycosis.

DIAGNOSES

The patient was diagnosed with psoriasis vulgaris with coexisting pemphigus vulgaris.

INTERVENTIONS

The patient was treated with modest doses of glucocorticoids combined with secukinumab and methotrexate.

OUTCOMES

The patient's generalized skin lesions and fingernails and toenails of the hands and feet healed virtually. There was no recurrence at 8 months follow-up, and no adverse effects were noted.

LESSONS

Moderate-dose glucocorticoids combined with secukinumab and methotrexate may be an option for treating psoriasis and pemphigus vulgaris. This case allows us to consider whether we can treat psoriasis vulgaris combined with pemphigus vulgaris based on a common pathogenesis, and to guide us in clinical dosing.

Fluorescent probes in autoimmune disease research: current status and future prospects

Autoimmune diseases (AD) present substantial challenges for early diagnosis and precise treatment due to their intricate pathogenesis and varied clinical manifestations. While existing diagnostic methods and treatment strategies have advanced, their sensitivity, specificity, and real-time applicability in clinical settings continue to exhibit significant limitations. In recent years, fluorescent probes have emerged as highly sensitive and specific biological imaging tools, demonstrating substantial potential in AD research.This review examines the response mechanisms and historical evolution of various types of fluorescent probes, systematically summarizing the latest research advancements in their application to autoimmune diseases. It highlights key applications in biomarker detection, dynamic monitoring of immune cell functions, and assessment of drug treatment efficacy. Furthermore, this article analyzes the technical challenges currently encountered in probe development and proposes potential directions for future research. With ongoing advancements in materials science, nanotechnology, and bioengineering, fluorescent probes are anticipated to achieve higher sensitivity and enhanced functional integration, thereby facilitating early detection, dynamic monitoring, and innovative treatment strategies for autoimmune diseases. Overall, fluorescent probes possess substantial scientific significance and application value in both research and clinical settings related to autoimmune diseases, signaling a new era of personalized and precision medicine.

JAK-STAT pathway, type I/II cytokines, and new potential therapeutic strategy for autoimmune bullous diseases: update on pemphigus vulgaris and bullous pemphigoid

Autoimmune Bullous Diseases (AIBDs), characterized by the formation of blisters due to autoantibodies targeting structural proteins, pose significant therapeutic challenges. Current treatments, often involving glucocorticoids or traditional immunosuppressants, are limited by their non-specificity and side effects. Cytokines play a pivotal role in AIBDs pathogenesis by driving inflammation and immune responses. The JAK-STAT pathway is central to the biological effects of various type I and II cytokines, making it an attractive therapeutic target. Preliminary reports suggest that JAK inhibitors may be a promising approach in PV and BP, but further clinical validation is required. In AIBDs, particularly bullous pemphigoid (BP) and pemphigus vulgaris (PV), JAK inhibitors have shown promise in modulating pathogenic cytokine signaling. However, the safety and selectivity of JAK inhibitors remain critical considerations, with the potential for adverse effects and the need for tailored treatment strategies. This review explores the role of cytokines and the JAK-STAT pathway in BP and PV, evaluating the therapeutic potential and challenges associated with JAK inhibitors in managing these complex disorders.

Antidesmoglein 1 and 3 serum IgG and positivity by direct immunofluorescence microscopy is associated with relapse in pemphigus in a prospective bicontinental study

Background

Prospective studies identifying immunological parameters that can predict clinical relapse in pemphigus are scarce.

Objective

To periodically assess immunological parameters in patients with pemphigus vulgaris and foliaceous in remission to understand immunological events preceding clinical relapse.

Methods

A total of 105 patients were included. Baseline assessment included direct immunofluorescence (DIF), serum IgG against desmoglein (Dsg) 1, IgG, IgG1, and IgG4 against Dsg 3, IgG against the extracellular domains 1 and 2 of Dsg 3, IgG against muscarinic (M3)-AchR, and peripheral CD19+CD27+ memory B cells/plasma cells, repeated every 3 months for up to 12 months or until clinical relapse. DIF was repeated at month 12 and on relapse.

Results

About 29 of 105 patients (28%) experienced a relapse. Longer duration of clinical remission, presence of pruritus and positive anti-Dsg1 at baseline correlated with higher relapse rates. Compared with the visit immediately preceding relapse, a significantly increased number of patients with positive anti-Dsg1 (38% vs 31.1%, P = .01), anti-Dsg3 (51.7% vs 41.4%, P = .01) and IgG positivity by DIF (85.7% vs 25%, P < .001) was observed at the time of relapse.

Conclusion

Regular monitoring of anti-Dsg 1 and anti-Dsg 3 serum levels and DIF positivity during the course of the disease in remission may predict relapse.

Diagnostic methods and strategies for autoimmune bullous diseases

INTRODUCTION

Autoimmune bullous disease (AIBD), showing blistering lesions on the skin and/or mucous membranes, is characterized by autoantibodies against various structural molecules present in keratinocyte cell surfaces and epidermal basement membrane zone. In addition to the clinical and pathological features, identification of specific autoantibodies is essential for AIBD diagnosis, and therefore corresponding methods should be well summarized and popularized.

AREA COVERED

Currently, direct immunofluorescence using biopsy tissue specimen and indirect immunofluorescence using normal human skin, 1 M NaCl-split skin and rat bladder are primarily used to identify tissue-bound and circulating autoantibodies, respectively. Immunoblotting and enzyme-linked immunosorbent assay (ELISA) methods have been developed for detection of autoantibodies against AIBD autoantigens, including desmoglein 1, desmoglein 3, BP180, BP230, type VII collagen, laminin (LM) 332, integrin α6β4, p200 (LMγ1/LMβ4) and human serum albumin. In this review, we summarized the detailed laboratory protocols for AIBD diagnosis methods used in our three institutes (Kurume University and Osaka Metropolitan University in Japan, and Daqing Oilfield General Hospital in China) before 9 October 2024.

EXPERT OPINION

This review will benefit both clinical practitioners and basic researchers on AIBD. In the future, simpler and easier AIBD diagnostic algorithms using a smaller number of tests should be established.

Optimizing Pemphigus Management With Rituximab and Short-Term Relapse Predictors

Importance

Rituximab is approved for the treatment of moderate to severe pemphigus. However, 20% of patients in the RITUX 3 trial relapsed within the first year of treatment.

Objective

To assess the outcome of an additional rituximab infusion at month 6 in patients with pemphigus who were in complete remission (CR) after rituximab regimen but had 1 or more predictors of relapse at month 3.

Design, Settings, and Participants

This multicenter cohort study was conducted in France from September 2018 to June 2023 to assess patients with newly diagnosed pemphigus who were in CR after treatment with the RITUX 3 regimen but had predictors of relapse at month 3. Relapse factors were a Pemphigus Disease Area Index (PDAI) score of 45 or higher, desmoglein 1 (DSG1) antibodies greater than 20 IU/mL, and/or DSG3 antibodies greater than 130 IU/mL.

Exposure

Patients in CR at month 6 with at least 1 predictor of relapse were treated with an additional rituximab infusion at month 6.

Main Outcomes and Measures

Primary end point was the rate of CR without corticosteroid therapy for 2 months at month 12. Secondary end points were the rate of relapse, number of patients needing to be re-treated (NNT) with rituximab to avoid a relapse, and safety.

Results

The study population comprised 87 patients (44 females [50.6%] and 43 [49.4%] males), with a mean (SD [range]) age of 55.3 (15.2 [24-92]) years at pemphigus diagnosis. Of these, 64 patients (73.6%) had pemphigus vulgaris and 23 (26.4%) had pemphigus foliaceus. At month 6, CR had been achieved by 77 patients (88.5%), and 10 (11.5%) had persistent disease activity. Of the 77 patients in CR, 30 (39.0%) had at least 1 predictor of relapse and received an additional infusion of rituximab; 47 patients (61.0%) without a predictor did not. Two patients without a predictor and no patients with a predictor experienced relapse-an overall relapse rate of 2.6% and an NNT of 3.6 (95% CI, 1.6-46.5). The 10 patients (11.5%) with persistent disease activity at month 6 were re-treated with rituximab, 2000 mg. At month 12, the rate of CR without corticosteroid therapy for a minimum of 2 months was 72 of 77 (93.5%) among patients who had achieved CR at month 6, and 72 of 87 (82.7%) for the whole study population. Eight serious adverse effects were reported among 5 patients; there were no deaths.

Conclusion and Relevance

This multicenter cohort study indicates that using predictors such as baseline PDAI score, anti-DSG1 antibodies, and/or anti-DSG3 antibodies to initiate preemptive treatment with additional rituximab may reduce the rate of short-term relapse.

Corticosteroids combined with low-dose methotrexate in the treatment of pemphigus vulgaris: A retrospective cohort study

The treatment of pemphigus vulgaris (PV) often requires long-term systemic corticosteroids. Although new biologicals like rituximab are changing the landscape, traditional immunosuppressants still prevail in many underdeveloped areas. One such medication is methotrexate (MTX), which has been widely used in autoimmune and autoinflammatory diseases, but its role in treating pemphigus remains somewhat unclear and controversial. This study aimed to evaluate the effect and safety profile of using low-dose MTX in PV patients receiving glucocorticoids. PV patients who visited the Department of Dermatology, Peking University First Hospital from January 2010 to December 2021 were retrospectively screened. Based on different treatment regimens, patients were automatically divided into a corticosteroid monotherapy group and a corticosteroid combined with low-dose MTX group (MTX was administered at a dose of no more than15 mg per week, with a minimum duration of 8 weeks). All patients were followed up for 1 year. A total of 142 patients with PV were eligible for the study (100 in the corticosteroid monotherapy group and 42 in the corticosteroid combined with low-dose MTX group). The Kaplan-Meier curve indicated that the corticosteroid combined with low-dose MTX group achieved a 50% reduction in glucocorticoid use faster, with a P value of 0.0132, especially among patients who initially received more than 60 mg of steroids per day. The inclusion of MTX reduced the occurrence of hyperpilidemia. There was not sufficient evidence to determine if the addition of MTX was associated with more bacterial infection cases for certain. The inclusion of low-dose MTX in the corticosteroid treatment regimen for patients with PV, particularly those receiving high doses, can facilitate the reduction of glucocorticoid dosages and lower the incidence of hyperlipidemia, without increasing the risk of other adverse effects.

Lenvatinib-induced pemphigus erythematosus in hepatocellular carcinoma: a unique case report

Adjuvant lenvatinib in combination with transarterial chemoembolization (TACE) has demonstrated prolonged disease-free survival in hepatocellular carcinoma patients at high risk of recurrence post-resection. Here, we present the case of a 68-year-old woman who developed serious side effects including pemphigus erythematosus (PE) linked to lenvatinib usage. Initially treated for breast cancer with radical surgery in April 2018 followed by adjuvant therapy, she was later diagnosed with liver cancer, initially mistaken for metastatic breast cancer to the liver. Although systemic treatment for advanced breast cancer was received, the tumor continued to progress and required partial removal of the liver after final evaluation. Subsequent pathology revealed hepatocellular carcinoma combined with risk factors for recurrence, prompting adjuvant therapy with TACE and oral lenvatinib. After three weeks of lenvatinib administration, the patient developed a skin rash diagnosed as PE through skin pathology. Treatment involved oral methylprednisolone, intravenous human immune globulin, and supportive care, resulting in a cure within a month. This unique case highlights the importance of further research not only on lenvatinib but also on monitoring and managing adverse reactions associated with targeted drugs to optimize patient safety and treatment outcomes.

COVID-19 infection is associated with an elevated risk for autoimmune blistering diseases while COVID-19 vaccination decreases the risk: A large-scale population-based cohort study of 112 million individuals

BACKGROUND

Numerous diseases associated with COVID-19 infection and vaccination have been reported, including conditions such as the autoimmune blistering diseases (AIBDs) pemphigus and pemphigoid. However, robust evidence supporting these associations is lacking.

OBJECTIVE

To investigate the risk of developing AIBD following COVID-19 infection and vaccination.

METHODS

Population-based retrospective cohort study utilizing data from over 112 million patients. The risk of AIBD within 3 months was compared among 3 cohorts: COVID-19 infection, COVID-19 vaccination, and controls, along with 7 sensitivity analyses.

RESULTS

COVID-19 infection was associated with an increased risk of AIBD (hazard ratio [HR] 1.508, 95% CI 1.260-1.805), with the risk being more pronounced for pemphigus (HR 2.432, 1.618-3.657) compared to bullous pemphigoid (HR 1.376, 1.019-1.857). Conversely, COVID-19 vaccination was associated with an almost halved risk of AIBD (HR 0.514, 0.394-0.672), with the risk reduction most significant for pemphigus (HR 0.477, 0.241-0.946). Comparisons between COVID-19 infection and vaccination revealed a more than threefold increased risk of AIBD in the infection cohort (HR 3.130, 2.411-4.063), particularly for pemphigus (HR 5.508, 2.973-10.205).

LIMITATIONS

Retrospective design and potential under-reporting of COVID-19 cases and vaccinations.

CONCLUSION

COVID-19 infection significantly increases the risk of AIBD while vaccination appears to reduce this risk.

FcRn inhibitors: Transformative advances and significant impacts on IgG-mediated autoimmune diseases

Pathogenic IgG autoantibodies play a crucial role in the pathogenesis of autoimmune diseases, and removal of pathogenic IgG autoantibodies is an important therapeutic approach and tool for such diseases. The neonatal Fc receptor (FcRn) interacts with IgG and protects it from lysosomal degradation. FcRn inhibitors accelerate the clearance of IgG antibodies, including pathogenic IgG autoantibodies, by targeting and blocking the binding of FcRn to IgG. Theoretically, FcRn inhibitors can be applied for the treatment of IgG-mediated autoimmune diseases. With successful completion of multiple relevant clinical trials, key evidence-based data have been provided for FcRn inhibitors in the treatment of IgG-mediated autoimmune diseases, and several FcRn inhibitors have been approved for these indications. Additional trials are being planned or conducted. This review examines all available high-quality clinical trials of FcRn inhibitors assessing IgG-mediated autoimmune diseases.

Immunohistochemistry for Immunoglobulin G4 on Paraffin Sections as a Diagnostic Test for Pemphigus

ABSTRACT

Pemphigus is a group of autoimmune bullous diseases mediated by autoantibodies most often of the immunoglobulin G class, subclasses immunoglobulin G1, and immunoglobulin G4 (IgG4), directed against desmosomal adhesion proteins of keratinocytes. This study aimed to evaluate IgG4 immunoreactivity on paraffin sections using immunohistochemistry in patients with pemphigus as a diagnostic test. Fifty formalin-fixed paraffin-embedded specimens from patients with pemphigus were selected. Fifty formalin-fixed paraffin-embedded specimens from patients with bullous diseases other than pemphigus were used as controls. Biopsies were performed on active lesions in newly diagnosed patients. Immunohistochemistry for IgG4 was performed on paraffin sections with an anti-immunoglobulin G4 antibody. Positivity was defined as distinctive, uninterrupted immunoreactivity localized to the intercellular junctions of keratinocytes. A finding that did not meet these criteria was defined as negative. Forty-three (86.0%) of the examined patients had pemphigus vulgaris and 7 (14%) had pemphigus foliaceus. Forty-nine (98.0%) specimens from patients with pemphigus were immunoreactive for IgG4, 1 (2%) upper back biopsy from the patient with oral pemphigus showed negative immunoreactivity for IgG4. Negative immunoreactivity was found in 45 (90%) controls. Five (10%) controls with bullous pemphigoid showed immunoreactivity for IgG4. Sensitivity of the method was established to be 98% and specificity 90%. Immunohistochemical examination for IgG4 for the diagnosis of pemphigus can be applied when direct immunofluorescence examination is unavailable. The advantage of this method is that it does not require special equipment and the histology slides are permanent.

Localization of Lesions in Autoimmune Blistering Diseases Is Independent of Site-Specific Target Antigen Expression

Autoimmune blistering diseases (AIBDs) involve autoantibodies targeting proteins in the epidermal/epithelial desmosome (pemphigus) or basement membrane zone (pemphigoid). Despite widespread antigen distribution, lesions exhibit a scattered involvement pattern. This study maps the frequency/severity of AIBD lesions on various body parts and investigates whether differential antigen expression contributes to specific predilection sites. We analyzed affected sites presenting blisters/erosions, erythematous/urticarial lesions, and mucosal lesions in bullous pemphigoid (BP-cohort 1, n = 65; BP-cohort 2, n = 119), pemphigus vulgaris (PV, n = 67), and pemphigus foliaceus (PF, n = 20) patients. To assess antigen expression, we conducted indirect immunofluorescence (IF) staining of 11 AIBD antigens from 13 anatomical sites of 10 body donors without AIBD. In BP, blisters/erosions and erythematous/urticarial lesions predominantly affected arms and legs, while PV/PF patients exhibited frequent involvement of buccal mucosa and back, respectively. IF staining identified significant regional differences in BP180, BP230, and integrin β4 expression, although these variations did not correlate with a higher lesion frequency/severity. Other antigens showed consistent expression across all regions. Our findings suggest that predilection sites for BP and PV/PF are largely unaffected by regional variations in antigen expression but may be influenced by factors like microbiota, mechanical stress, sunlight exposure, local immunity, or genetics.

Evaluation of the Effects of systemic Therapy on Inflammatory Markers and Disease Severity in Patients with Pemphigus

INTRODUCTION

In recent years, various inflammatory markers that can change in inflammatory states have been investigated. On the basis of these, we thought that inflammatory markers could also be used in the follow-up of pemphigus disease and monitoring its activity.

OBJECTIVES

In this study, our objective was to investigate changes in the inflammatory markers neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), mean platelet volume (MPV), lymphocyte to monocyte ratio (LMR), C-reactive protein (CRP) erythrocyte sedimentation rate (ESR), which are inflammatory markers, before treatment and during follow-up, and the correlation of disease severity with these markers in patients with pemphigus receiving intravenous immunoglobulin (IVIG) and/or systemic immunosuppressant agents.

METHODS

Seventy-six pemphigus patients (69 had pemphigus vulgaris, 5 had pemphigus foliaceus, 2 had paraneoplastic pemphigus) who received IVIG and/or systemic immunosuppressant agents such as corticosteroids and azathioprine and used these treatments for at least 6 months were included. Changes in NLR, PLR, LMR, MPV, CRP and sedimentation values were examined in patients who received systemic treatment for at least 6 months, before the start of treatment and 3 and 6 months after the start of treatment.

RESULTS

Significant changes in inflammatory markers and correlation values were found in all patients.

CONCLUSIONS

We think that neutrophil, platelet, NLR and PLR values can be used to monitor the response to treatment in pemphigus, since they show a significant decrease with treatment and are significantly positively correlated with Pemphigus Disease Area Index, which indicates the severity of the disease. LMR values were indicators of a poor prognosis. We found that the duration of remission was longer in the group receiving IVIG. Although there was no difference between the treatments in terms of disease recovery, only IVIG prolonged the duration of remission.

The role of BATF in immune cell differentiation and autoimmune diseases

As a member of the Activator Protein-1 (AP-1) transcription factor family, the Basic Leucine Zipper Transcription Factor (BATF) mediates multiple biological functions of immune cells through its involvement in protein interactions and binding to DNA. Recent studies have demonstrated that BATF not only plays pivotal roles in innate and adaptive immune responses but also acts as a crucial factor in the differentiation and function of various immune cells. Lines of evidence indicate that BATF is associated with the onset and progression of allergic diseases, graft-versus-host disease, tumors, and autoimmune diseases. This review summarizes the roles of BATF in the development and function of innate and adaptive immune cells, as well as its immunoregulatory effects in the development of autoimmune diseases, which may enhance the current understanding of the pathogenesis of autoimmune diseases and facilitate the development of new therapeutic strategies.

A comprehensive, population level evaluation of previously reported drug triggers of pemphigus highlights immunomodulatory capacity as a common characteristic

Question

Can previously reported, largely anecdotal associations between exposure to any of a comprehensive list of putative trigger drugs and the development of pemphigus be reproduced using population level data?

Findings

In this series of observational, retrospective, case-control, pharmacovigilance analyses of the FDA Adverse Event Reporting System, the odds of reporting the adverse event pemphigus were significantly elevated among individuals exposed to 11/36 previously reported trigger drugs namely, gold sodium thiomalate, penicillamine, piroxicam, rifampin, hydroxychloroquine, imiquimod, hydrochlorothiazide, irbesartan, lisinopril, nivolumab, and nifedipine.

Meaning

Environmental exposures such as drugs are relevant players in the pathogenesis of autoimmune diseases and clinicians who treat patients with autoimmune blistering diseases such as pemphigus should consider performing a detailed medication history leveraging this information regarding deleterious drug-disease interactions at initial evaluation as well as longitudinal monitoring of patients to better inform clinical care decisions.

Importance

Pemphigus vulgaris (PV) is a rare, potentially fatal autoimmune disease with pathogenic contributions from both genetic as well as environmental factors, notably drug exposures. Despite anecdotal reports linking multiple drugs to PV, corroborating evidence from large datasets is missing.

Objective

To examine the extent to which previously reported associations between a comprehensive list of 36 drugs implicated in PV pathogenesis could be replicated using population-level pharmacovigilance data.

Design

Series of observational, retrospective, case-control, pharmacovigilance analyses (one analysis/drug, 36 total).

Setting

Population based.

Participants

Individuals who submitted a report of a drug-related adverse event to the FDA from Q4 of 2003 to Q2 of 2023.

Exposure

Cases were identified by the presence of adverse events described by the MedDRA preferred term "pemphigus" (10034280) and then sorted based on exposure to each of the drugs of interest.

Main outcomes and measures

Reporting Odds Ratios (RORs) quantifying the association between a given drug exposure and reports of pemphigus adverse events.

Results

The analyses revealed statistically significant associations between reports of pemphigus and exposure to 11/36 previously reported drugs, two of which had particularly high RORs (>200) [gold sodium thiomalate (ROR, 266.0; 95% CI, 202.6-349.3) and hydroxychloroquine (ROR, 282.6; 95% CI, 261.0-306.1)], three had very strong RORs (14-45) [penicillamine (ROR, 30.5; 95% CI, 11.4-81.7), piroxicam (ROR, 14.8; 95% CI, 8.2-26.7), and imiquimod (ROR, 42.3; 95% CI, 26.2-68.3)], and six had modestly strong RORs (2-5) [rifampin (ROR, 2.8; 95% CI, 1.4-5.6), hydrochlorothiazide (ROR, 1.6; 95% CI, 1.2-2.1), irbesartan (ROR, 2.7; 95% CI, 1.6-4.4), lisinopril (ROR, 5.3; 95% CI, 4.5-6.2), nivolumab (ROR, 2.7; 95% CI, 1.8-4.1), and nifedipine (ROR, 3.0; 95% CI, 1.9-5.0)]. Associations for other previously reported drugs (25/36) were not detected.

Conclusions and relevance

This study represents a comprehensive evaluation of suspected drug triggers of pemphigus using real-world data. The significant associations reported here provide empirical support for the hypothesis that certain drugs act as triggers for PV. Moreover, all of the drugs found to be associated with PV in this study harbor immunomodulatory capacity, suggesting that the ability to induce such perturbations, directly or indirectly, may be a critical factor connecting drug exposure to pemphigus pathogenesis. However, the absence of signals for other previously reported putative trigger drugs does not preclude their potential role in PV pathogenesis. Our findings reinforce the need for larger, more definitive studies to confirm these associations and to explore the mechanisms by which these drugs may contribute to PV development. Finally, these findings underscore the importance of considering environmental factors in the development and course of PV in genetically susceptible individuals.

The impact of signaling pathways on the desmosome ultrastructure in pemphigus

Introduction

The autoantibody-driven disease pemphigus vulgaris (PV) impairs desmosome adhesion in the epidermis. In desmosomes, the pemphigus autoantigens desmoglein 1 (Dsg1) and Dsg3 link adjacent cells. Dsgs are clustered by plaque proteins and linked to the keratin cytoskeleton by desmoplakin (Dp). The aim of this study was to identify the impact of several PV-related signaling pathways on desmosome ultrastructure.

Methods

STED microscopy, Dispase-based dissociation assay.

Results

As observed using STED microscopy, pemphigus autoantibodies (PV-IgG) reduced desmosome number, decreased desmosome size, increased plaque distance and thickness and caused loss of adhesion. Decreased desmosome number, increased plaque distance and thickness and loss of adhesion correlate with features found for newly assembled immature desmosomes, observed after Ca2+ depletion and repletion. This was paralleled by plaque asymmetry, keratin filament retraction and fragmentation of Dsg1 and Dsg3 immunostaining. Inhibition of each individual signaling pathway investigated here prevented the loss of adhesion and ameliorated keratin retraction. In addition, inhibition of p38MAPK or PLC completely rescued all parameters of desmosomes ultrastructure and increased desmosome number under basal conditions. In contrast, inhibition of MEK1/2 was only partially protective for desmosome size and plaque thickness, whereas inhibition of Src or increase of cAMP decreased desmosome size but increased the desmosome number even in the presence of PV-IgG.

Discussion

Alterations of the desmosomal plaque ultrastructure are closely related to loss of adhesion and regulated differently by signaling pathways involved in pemphigus pathogenesis. This insight may allow identification of novel treatment options targeting specific steps of desmosome turn-over in the future.

Prognostic Factors Predicting Remission Following Rituximab Therapy for Pemphigus Vulgaris

Pemphigus vulgaris is a chronic autoimmune blistering disease with significant morbidity. Rituximab, approved as its first-line treatment, effectively induces remission. However, few studies have analysed the prognostic factors for improved rituximab outcomes. Therefore, this study aimed to identify such factors in a cohort of pemphigus vulgaris patients. A total of 142 pemphigus vulgaris patients treated with rituximab at Sheba Medical Center, with data encompassing demographics, comorbidities, disease characteristics, and treatment outcomes, were retrospectively examined. Results showed that 61.9% of patients previously treated with mycophenolate mofetil achieved partial remission, whereas only 34.7% achieved complete remission. Patients with diabetes mellitus exhibited a significantly shorter median time to relapse compared with those without. Patients with a disease duration ≤ 16 months before rituximab therapy exhibited a shorter median time to relapse. Moreover, previous dapsone treatment extended time to relapse. Notably, sex, age at symptom onset and rituximab therapy, ethnicity, comorbidities, skin involvement, weight, rituximab dosing protocol, and other variables were not statistically significant between the complete remission and partial remission groups. These findings highlight the influence of specific patient characteristics and treatment histories on response to rituximab and time to relapse in pemphigus vulgaris patients. Understanding these factors can aid clinicians in predicting treatment outcomes and selecting the appropriate patient population for rituximab therapy.

Case report of the successful treatment of pemphigus vulgaris using ovine forestomach matrix graft

Pemphigus vulgaris (PV) is a subtype of pemphigus and life-altering disorder that results in the formation of intraepithelial blisters in mucosa and skin. Though the etiology is not well understood, it is an autoimmune disorder resulting in acantholytic blisters due to auto-antibodies targeting proteins of keratinocyte adhesion. Rapid diagnosis and restoration of the epidermal layer is imperative for patients with PV as widespread epidermal damage can lead to high morbidity and mortality rates. This case report presents the treatment of PV in a 53-year-old female who presented after 9 months of worsening symptoms and 30% total body surface area blistering. Most of the lesion was re-epithelialized in 1 week, with complete healing in 4 weeks following a single application of ovine forestomach matrix (OFM) graft. This case represents the first report of the use of OFM to aid regeneration of epithelial lesions resulting from an autoimmune bullous disease.

Evaluation of link between COVID-19 adjacent spike in hydroxychloroquine use and increased reports of pemphigus: a disproportionality analysis of the FDA Adverse Event Reporting System

Importance

Identifying environmental factors that contribute to disease onset/activity in PV stands to improve clinical outcomes and patient quality of life by strategies aimed at reducing specific disease promoting exposures and promoting personalized clinical management strategies.

Objective

To evaluate the association between hydroxychloroquine use and the development of pemphigus using population level, publicly available, FDA-generated data.

Design

Observational, retrospective, case-control, pharmacovigilance analysis.

Setting

Population based.

Participants

Individuals who either independently or via their healthcare provider submitted a voluntary report of a drug related adverse event to the FDA from Q4 of 2003 to Q2 of 2023.

Exposure

Cases were identified by the presence of adverse events described by the MedDRA preferred term (PT) of "pemphigus" (10034280) and then sorted based on exposure to the drug of interest, hydroxychloroquine, or lack thereof.

Main outcomes and measures

Frequency of hydroxychloroquine exposure among those individuals who reported an adverse event of pemphigus to the FDA; quantification of the reporting odds ratio (ROR).

Results

We identified a total of 2,548 reports that included the adverse event pemphigus; among these, 1,545 (n=706 (41.92%) age 18-64, n=1 age 65-85 years, and n=977 (58.02%) with no age specified; n=1,366 (81.12%) females, n=4 (0.24%) males, and n=314 (18.65%) with no gender specified) included exposure to hydroxychloroquine (ROR, 282.647; 95% CI, 260.951-306.148). We then stratified those reports that included the combination of pemphigus and hydroxychloroquine by gender and found that while the association between the exposure and adverse event remained significant across genders, the magnitude of the effect sizes differed significantly (p<0.001), being over 100-fold greater among females (ROR, 378.7; 95% CI, 339.0-423.1) compared to males (ROR, 3.6; 95% CI, 1.4-9.8).

Conclusions and relevance

The frequency of reports containing the combination of the adverse event pemphigus and exposure to the drug hydroxychloroquine was disproportionately elevated across all genders in the years since the start of the COVID-19 pandemic. The disproportionately elevated frequency of reports of the combination of pemphigus and hydroxychloroquine supports an association between the two, corroborates previous case-report based evidence for such an association, suggests that hydroxychloroquine represents a possible trigger factor for the development of pemphigus, and paves the way for future research that is capable of establishing causality.

HDAC1-mediated regulation of KDM1A in pemphigus vulgaris: unlocking mechanisms on ERK pathway activation and cohesion loss

Pemphigus vulgaris (PV) is an autoimmune skin disorder characterized by the loss of cell cohesion, with the histone deacetylase 1 (HDAC1) and lysine demethylase 1A (KDM1A) playing critical roles in its pathogenesis. This study aimed to elucidate the molecular mechanisms behind PV, focusing on the function of HDAC1 and KDM1A in disease onset and progression. Based on in vitro and in vivo PV models, we observed a significant increase in HDAC1 mRNA and protein levels in skin tissues of PV patients. Inhibition of HDAC1 ameliorated cell damage and reduced the loss of cell cohesion in human epidermal keratinocytes (HEKs) induced by PV-IgG. Our findings suggest that HDAC1 regulates KDM1A expression through deacetylation, with a notable deficiency in KDM1A expression in PV. Overexpression of KDM1A mitigated cell damage and cohesion loss. The extracellular signal-regulated kinase (ERK) pathway serves as a downstream executor of the HDAC1/KDM1A axis. Inhibiting HDAC1 and increasing KDM1A expression suppressed ERK phosphorylation, reducing PV-related apoptosis. These insights provide a new perspective on treating PV, highlighting the therapeutic potential of targeting HDAC1 expression. The regulatory mechanism of the HDAC1/KDM1A/ERK axis offers crucial clues for understanding PV pathogenesis and developing novel treatments.

Large-scale global retrospective study on the interaction between ancestry and risk of comorbid autoimmune diseases in patients with pemphigus

The pemphigus family of skin blistering diseases represents a rare yet potentially life-threatening condition characterized by multiple known genetic loci associated with other autoimmune disorders. While several studies have empirically indicated an increased risk of developing additional autoimmune diseases in individuals with pemphigus, the scarcity of data and the rarity of pemphigus have hindered efforts to establish and generalize these associations across diverse populations. In this study, we analyzed a dataset comprising 126 million patients, including 18,000 with pemphigus, to assess the likelihood of developing any of 74 autoimmune diseases following a diagnosis of pemphigus. For a subset of 26 diseases from this list with adequate patient numbers, we conducted further case-control retrospective analyses to quantify the odds and hazard ratios of developing comorbid conditions across various ethnicities. Our findings reveal highly significant and generalizable associations between pemphigus and pemphigoid diseases, discoid lupus erythematosus, lichen planus, and undifferentiated connective tissue disease, among others.

Mild cognitive impairment in pemphigus

BACKGROUND

Pemphigus is a group of autoimmune blistering disorders that have been associated with dementia in previous studies. Mild cognitive impairment (MCI) can be the first stage of progression into dementia. The objective of the present study was to evaluate the frequency of MCI in pemphigus patients compared to a control group.

METHODS

This case-control study included 80 patients with pemphigus referred to the dermatology clinics of Shohadaye Tajrish and Loghman Hakim hospitals, Tehran, Iran, in 2021. A group of 80 individuals without pemphigus who visited the same clinics for cosmetic consultation or interventions were regarded as controls. Age, sex, marital status, and education were recorded for all participants. Disease duration, medications, and severity were noted for pemphigus patients. The Persian version of the Montreal Cognitive Assessment (MoCA) test was used to assess cognitive function.

RESULTS

MCI was significantly more frequent in pemphigus patients than in controls (55% vs. 37.5%, P = 0.026). Furthermore, the total MoCA score was significantly lower in pemphigus patients compared to controls (23.98 ± 3.77 vs. 25.21 ± 3.45, P = 0.032); however, among MoCA's different domains, only the executive functions score was significantly lower in pemphigus patients (P = 0.010). After adjustment, multivariable logistic regression analysis revealed that every 1-year higher education in patients decreased the odds of MCI by 52% (adjusted odds ratio = 0.483, 95% confidence interval 0.326; 0.715, P < 0.001).

CONCLUSIONS

The frequency of MCI was found to be significantly higher, and overall scores of the MoCA test, as well as its executive function domain, were significantly lower among pemphigus patients in this study compared to the control group. Additionally, a higher level of education was associated with decreased odds of MCI in pemphigus patients. Identifying pemphigus patients with MCI through the use of the MoCA test can facilitate early intervention, enabling them to seek help and support.

The efficacy and safety of low-dose rituximab in the treatment of pemphigus vulgaris: a cohort study

BACKGROUND

Rituximab (RTX) is considered the first-line treatment for pemphigus vulgaris (PV), which is a B-cell-mediated acquired autoimmune disease. However, no consensus on the optimum dosage has been achieved.

OBJECTIVES

To investigate the efficacy and safety of low-dose RTX (a single infusion of 500 mg) for the treatment of PV, a cohort study was conducted for patients with PV, along with a 12-month follow-up following the administration of RTX.

METHODS

Patients with moderate or severe PV were divided into group A (low-dose RTX combined with corticosteroids) and group B (corticosteroids alone). Data on complete remission (CR) rates, doses of corticosteroids, cumulative doses of corticosteroids at the third, sixth, and twelfth months, pemphigus disease area index and adverse effects (AEs) were collected.

RESULTS

Forty-four patients with moderate or severe PV were enrolled in this study (19 in group A and 25 in group B). Patients treated with low-dose RTX had higher CR rates, lower doses of corticosteroids at the third, sixth, and twelfth months, lower cumulative doses of corticosteroids at the sixth and twelfth months, and fewer AEs than those who received corticosteroids alone.

CONCLUSIONS

This study indicated that low-dose RTX may be a beneficial and secure therapy option for patients with moderate to severe PV.

Effect of opioid receptor antagonist on mitigating tumor necrosis factor-like weak inducer of apoptosis (TWEAK)-induced apoptolysis in pemphigus pathogenesis

Pemphigus is a severe autoimmune blistering disease characterized by acantholysis triggered by autoantibodies against desmoglein 1 and 3 (DSG1/3). Apoptosis plays a pivotal role in facilitating acantholysis, yet the precise underlying mechanism remains obscure. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is known to promote apoptosis and disrupt cell junctions, although its involvement in pemphigus pathogenesis remains ambiguous. Our study observed decreased DSG1/3 expression alongside increased TWEAK/fibroblast growth factor-inducible 14 (Fn14) expression and keratinocyte apoptosis in both lesional and perilesional skin. In vitro experiments revealed that TWEAK-stimulated keratinocytes exhibited enhanced apoptosis, STAT1 phosphorylation, and reduced intercellular DSG1/3 expression. Notably, bulk-RNA sequencing unveiled that CASPASE-3 was responsible for mediating the DSG1/3 depletion, as confirmed by direct interaction with DSG1/3 in a co-immunoprecipitation assay. Naloxone, known for preserving cellular adhesion and preventing cell death, effectively reduced apoptosis and restored DSG1/3 levels in TWEAK-stimulated keratinocytes. The anti-apoptotic properties of naloxone were further validated in a murine pemphigus model. Our findings elucidate that TWEAK facilitates keratinocyte apoptosis by augmenting caspase-3 activity, leading to DSG1/3 depletion and apoptosis in pemphigus. Importantly, naloxone can counter TWEAK-induced apoptosis in pemphigus pathogenesis, offering a potential therapeutic intervention.

Coexistence of Pemphigus Foliaceus and Bullous Pemphigoid: A Case Report

Pemphigus foliaceus (PF) and bullous pemphigoid (BP) are distinct autoimmune bullous skin diseases mediated by autoantibodies targeting adhesion molecules in desmosomes and hemidesmosomes structural proteins in the epidermal-basement membrane zone, respectively. The coexistence of PF and BP is rare. We present the case of a 72-year-old male with clinical and histological features of both PF and BP. Treatment with immunoglobulin (10 g/day for 3 days), intravenous dexamethasone sodium phosphate (5 mg/day for 10 days), oral triamcinolone (30 mg/day for 10 days), and minocycline hydrochloride (20 mg/day for 10 days) resulted in significant improvement. This rare case highlights the importance of accurate diagnosis and effective treatment strategies for the coexistence of PF and BP.

Topographical variations in the skin barrier and their role in disease pathogenesis

The skin barrier can be divided into at least four functional units: chemical, microbial, physical and immunological barriers. The chemical and microbial barriers have previously been shown to exhibit different characteristics in topographically distinct skin regions. There is increasing evidence that the physical and immunological barriers also show marked variability in different areas of the skin. Here, we review recent data on the topographical variations of skin barrier components, the contribution of these variations to the homeostatic function of the skin and their impact on the pathogenesis of specific immune-mediated skin diseases (such as atopic dermatitis and papulopustular rosacea). Recognition of these topographical barrier differences will improve our understanding of skin homeostasis and disease pathogenesis and provide a basis for body site-specific targeted therapies.

Conjoint analysis of methylation, transcriptomic, and proteomic profiles in pemphigus vulgaris

BACKGROUND

The underlying pathogenesis of pemphigus vulgaris, an autoimmune skin disorder, remains incompletely understood. An integrative analysis comprising DNA methylation, mRNA expression, and proteomic data in patients with pemphigus vulgaris was conducted to identify potential pathogenic contributors and explore the molecular mechanisms involved in its pathogenesis.

RESULTS

The analysis revealed differentially methylated regions (DMRs) in the promoter, exon, intron, and downstream regions in the peripheral blood DNA of patients with pemphigus vulgaris. Associations between methylation levels and both transcriptomic and proteomic profiles revealed that differentially expressed genes between patients with pemphigus vulgaris and healthy controls were primarily linked to biological functions such as platelet activation and coagulation, cellular adhesion, and immunoglobulin binding. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis highlighted notable pathway abnormalities, including those related to platelet activation, focal adhesions, tight junctions, and infectious inflammatory responses. Notably, genes such as FGA (fibrinogen alpha chain), VWF (von Willebrand factor), and ACTG1 (actin gamma 1) were dysregulated, with a prominent role in platelet activation.

CONCLUSION

The dysregulation of genes such as FGA, VWF, and ACTG1 suggests that alterations in their transcription and expression may contribute to the pathogenesis of pemphigus vulgaris.

Autoimmune disease: a view of epigenetics and therapeutic targeting

Autoimmune diseases comprise a large group of conditions characterized by a complex pathogenesis and significant heterogeneity in their clinical manifestations. Advances in sequencing technology have revealed that in addition to genetic susceptibility, various epigenetic mechanisms including DNA methylation and histone modification play critical roles in disease development. The emerging field of epigenetics has provided new perspectives on the pathogenesis and development of autoimmune diseases. Aberrant epigenetic modifications can be used as biomarkers for disease diagnosis and prognosis. Exploration of human epigenetic profiles revealed that patients with autoimmune diseases exhibit markedly altered DNA methylation profiles compared with healthy individuals. Targeted cutting-edge epigenetic therapies are emerging. For example, DNA methylation inhibitors can rectify methylation dysregulation and relieve patients. Histone deacetylase inhibitors such as vorinostat can affect chromatin accessibility and further regulate gene expression, and have been used in treating hematological malignancies. Epigenetic therapies have opened new avenues for the precise treatment of autoimmune diseases and offer new opportunities for improved therapeutic outcomes. Our review can aid in comprehensively elucidation of the mechanisms of autoimmune diseases and development of new targeted therapies that ultimately benefit patients with these conditions.

Laboratory and clinical haemostatic aberrations in primary dermatologic disease: A review

Inflammatory dermatologic diseases have long been viewed as a "skin limited" disease process. Current literature on inflammatory dermatologic diseases investigates their relationship and influence on thromboembolic states and thromboembolic complications and the understanding of their pathophysiology and molecular mechanisms.Studies specifically discuss known inflammatory skin diseases including alopecia areata, vitiligo, psoriasis, hidradenitis suppurativa, atopic dermatitis, chronic spontaneous urticaria, and autoimmune bullous diseases, and their effects on systemic inflammation, associated cardiovascular comorbidities, and thromboembolic or hypercoagulable states. The limited current literature shows potential for links between inflammatory skin diseases and hypercoagulable states. Biomarkers such as F1 + 2, D-dimer, eosinophilic cationic protein, and PAI-1 are currently being studied to outline the mechanisms connecting inflammatory skin disease to the coagulation system. Further study and larger amounts of data are needed to draw definitive conclusions, especially when interpreting biomarkers alone such as PAI-1.The mechanisms, rates of systemic inflammation, and clinical outcomes of traditionally "skin limited" inflammatory diseases remain chronically understudied in dermatology. Many organ systems have well established connections between inflammatory disease and hypercoagulable states, but there are significant gaps in the literature regarding skin diseases. There is a significant need for comprehensive investigation of molecular mechanisms behind inflammatory dermatologic disease and hypercoagulability, how hypercoagulability effects clinical outcomes, and proper intervention to optimize patient outcomes.

EGFR Inhibition by Erlotinib Rescues Desmosome Ultrastructure and Keratin Anchorage and Protects against Pemphigus Vulgaris IgG-Induced Acantholysis in Human Epidermis

Pemphigus is a severe blistering disease caused by autoantibodies primarily against the desmosomal cadherins desmoglein (DSG)1 and DSG3, which impair desmosome integrity. Especially for the acute phase, additional treatment options allowing to reduce corticosteroids would fulfill an unmet medical need. In this study, we provide evidence that EGFR inhibition by erlotinib ameliorates pemphigus vulgaris IgG-induced acantholysis in intact human epidermis. Pemphigus vulgaris IgG caused phosphorylation of EGFR (Y845) and Rous sarcoma-related kinase in human epidermis. In line with this, a phosphotyrosine kinome analysis revealed a robust response associated with EGFR and Rous sarcoma-related kinase family kinase signaling in response to pemphigus vulgaris IgG but not to pemphigus foliaceus autoantibodies. Erlotinib inhibited pemphigus vulgaris IgG-induced epidermal blistering and EGFR phosphorylation, loss of desmosomes, as well as ultrastructural alterations of desmosome size, plaque symmetry, and keratin filament insertion and restored the desmosome midline considered as hallmark of mature desmosomes. Erlotinib enhanced both single-molecule DSG3-binding frequency and strength and delayed DSG3 fluorescence recovery, supporting that EGFR inhibition increases DSG3 availability and cytoskeletal anchorage. Our data indicate that EGFR is a promising target for pemphigus therapy owing to its link to several signaling pathways known to be involved in pemphigus pathogenesis.

Oral lichen planus-like lesions in skin of color: a review

In dermatology, lichenoid describes lesions with a violaceous hue that is a clinical reflection of basal cell damage in the epithelium and dense mononuclear infiltrate in the sub-epithelium. The violaceous color results from pigment incontinence due to basal cell damage and the Tyndall effect. Although classically described in lichen planus, a lichenoid hue is noted in the oral mucosa in several other disorders that often lead to diagnostic dilemmas. Early and accurate diagnosis is important for the appropriate management of the underlying condition and prognostication. Dermatologists play a central role in managing such patients since, apart from the oral mucosa findings, the cutaneous features also help to significantly differentiate various conditions. Mimickers of oral lichen planus include nicotine stomatitis, oral submucous fibrosis, oral lichenoid lesions, mucosal discoid lupus erythematosus, pemphigus vulgaris, paraneoplastic pemphigus, mucous membrane pemphigoid, fixed drug eruption, plasma cell cheilitis/gingivitis, and erythema multiforme. While a detailed history and clinical examination can help reach a diagnosis in most cases, histopathology, immunofluorescence, and other relevant investigations help establish the diagnosis.

Establishing minimal clinically important differences for the Pemphigus Disease Area Index

BACKGROUND

Pemphigus is a rare autoimmune blistering disease with potentially life-threatening consequences. Establishing minimal clinically important differences (MCIDs) for disease severity scores like the Pemphigus Disease Area Index (PDAI) is crucial for assessing treatment efficacy.

OBJECTIVES

To calculate MCIDs for both improvement and deterioration in PDAI scores in patients with pemphigus vulgaris (PV) and pemphigus foliaceus (PF), using the anchor-based method.

METHODS

A total of 41 patients with pemphigus were recruited, with 35 meeting the MCID analysis criteria. The anchor-based method was used to calculate MCIDs for PDAI scores against the 15-point Likert scale and the Physician Global Assessment visual analogue scale (PGA-VAS) anchors. Receiver operating characteristic curves were employed to determine optimal MCID cutpoints with the highest Youden Index (J). The 15-point Likert scale scores the change in disease severity spanning from -7 to +7, designed to quantify the extent of disease improvement/deterioration since the preceding visit.

RESULTS

The MCID for improvement in PDAI activity scores was 2.65 points using the 15-point Likert scale (78.7% correct classification; sensitivity 75.9%; specificity 73.5%) and 2.5 points using the PGA-VAS as the anchor (78.0% correct classification; sensitivity 84.4%; specificity 68.2%). Given the slightly higher correct classification rate using the 15-point Likert scale anchor, the MCID of 2.65 points was selected for PDAI activity score improvement. In contrast, the MCID for deterioration consistently remained at 2.5 points for the 15-point Likert scale anchor (81.0% correct classification; sensitivity 72.7%; specificity 81.0%) and 2.5 points for the PGA-VAS anchor (70.9% correct classification; sensitivity 69.6%; specificity 76.9%).

CONCLUSIONS

This study marks the inaugural attempt at MCID determination for PDAI scores in pemphigus, filling a critical knowledge gap. The study's calculated MCIDs provide essential benchmarks for clinical trials, treatment evaluation and research design optimization. Future studies should explore international collaborations, to examine potential cross-cultural variations in MCIDs.

Association of four CTLA-4 gene polymorphisms with pemphigus risk: a systematic review, meta-analysis, and meta-regression

OBJECTIVES

This review aimed to summarize the existing data on the contribution of four single nucleotide polymorphisms (SNPs) in the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) genes to pemphigus susceptibility.

METHODS

An electronic literature search for eligible studies among those published prior to 30 April 2024 was conducted through the PubMed, EMBASE, Web of Science, and Scopus databases. To minimize publication bias, an additional search was performed via the Google Scholar and Semantic Scholar search engines. Meta-analyses, together with subgroup analyses and meta-regressions, were performed for the following four CTLA-4 SNPs: rs231775, rs5742909, rs3087243, and rs733618.

RESULTS

Combined analyses revealed a significant increase in pemphigus risk conferred by the CTLA-4 rs5742909*C and rs733618*C alleles. Conversely, there was no evidence of any significant association between the rs231775*G and rs3087243*G alleles and susceptibility to pemphigus. Subgroup analyses by ethnicity and pemphigus type (vulgaris or foliaceus) and meta-regressions did not reveal any significant difference.

CONCLUSION

This meta-analysis suggested that two of the four investigated CTLA-4 SNPs were significantly associated with increased pemphigus risk.Registration: This review has been registered on PROSPERO: CRD42024550668; available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024550668.