Direct immunofluorescence on plucked hair outer root sheath can predict relapse in pemphigus vulgaris.

BACKGROUND: Prospective research is lacking on the utility of plucked hair outer root sheath direct immunofluorescence (ORS DIF) in the prediction of relapse in pemphigus vulgaris (PV) and the correlation of ORS DIF positivity with serum desmoglein antibody titers. METHODS: We performed a prospective cohort study enrolling 80 PV patients in complete clinical remission at a tertiary care center in North India. Study participants underwent ORS DIF at baseline, which was repeated every 3 months. Skin biopsy DIF was done at study inclusion, repeated at 3 months, and upon clinical relapse. An antidesmoglein antibody titer was assessed concurrently with ORS DIF in a subset of patients. Patients on adjuvant therapy had their adjuvant therapy withdrawn either at the initial visit, at 3 months, or at a 6-month follow-up. Our objectives were to determine the association between positive ORS DIF and clinical relapse, the correlation between positive ORS DIF and skin biopsy DIF, and between positive ORS DIF and positive antidesmoglein antibody titers (when concurrently done). RESULTS: Twenty-two patients (27.5%) had a clinical relapse. Baseline immunological markers significantly associated with relapse are ORS DIF positivity with IgG (16/36 [45.44%] P = 0.005) and C3 (12/29 [41.37%] P = 0.047) and greater intensity of baseline IgG and C3 positivity in ORS DIF (IgG, P = 0.002; C3, P = 0.033). Notably, a significant correlation was observed between baseline positive ORS DIF and skin biopsy DIF (IgG, ρ = 0.695; C3, ρ = 0.498). Positive ORS DIF strongly correlated with positive anti-Dsg3 antibody titers (φs = 0.815; P < 0.01). Early withdrawal of adjuvant immunosuppressant (within 3 months) (P = 0.007) and positive ORS DIF were also associated with relapse (P = 0.017). CONCLUSION AND RELEVANCE: ORS DIF is a reliable predictor of PV clinical relapse and demonstrated robust correlations with skin biopsy DIF and antidesmoglein antibody titers. Periodic assessment of ORS DIF aids in determining new-onset positivity that heralds clinical relapse.

Rituximab-induced serum sickness in immunobullous disorders: A case series.

Key Clinical Message: Rituximab-induced serum sickness (RISS) is a rare complication of Rituximab (RTX) in immunobullous disorders. Clinicians should be aware of the occurrence of serum sickness symptoms during RTX administration, and prompt initiation of corticosteroid therapy is crucial in these patients. Additionally, RISS may occur with subsequent RTX doses and patients should be counseled accordingly. Abstract: Rituximab (RTX) is a chimeric monoclonal anti-CD20 antibody which has gained approval for the treatment of various autoimmune and lymphoproliferative disorders. While RTX-induced minor reactions, including immediate infusion-related reactions, are common, serum sickness is rare. Limited data exist regarding rituximab-induced serum sickness (RISS) in pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP). We report two cases of RISS following RTX administration in PV and MMP patients. Both patients presented with typical symptoms of serum sickness after RTX infusion, necessitating drug cessation and corticosteroid therapy for resolution. RISS represents a rare complication of RTX therapy. Clinicians should maintain awareness of serum sickness presentations during and post-RTX administration.

Epidemiological Insights into Autoimmune Bullous Diseases in China: A Comprehensive Analysis.

OBJECTIVE: This study aims to conduct an extensive analysis of autoimmune bullous diseases, particularly pemphigus vulgaris and bullous pemphigoid, in Shanghai, China, from 2016 to 2023. It seeks to understand the demographic profiles, comorbidities, mortality rates, risk factors, and socioeconomic impacts associated with autoimmune bullous disease. METHODS: A cross-sectional study design was employed, enrolling 1,072 patients. Diagnostic measures included clinical manifestations, histopathology, direct immunofluorescence, and serologic tests. The study also involved a detailed socioeconomic analysis and evaluation of occupational risks. RESULTS: The findings highlight a significant occupational risk in industries requiring enhanced safety measures, with a notable prevalence of autoimmune bullous disease among workers in these sectors. A considerable portion of the patients were from low-income backgrounds with limited literacy, indicating the economic burden of autoimmune bullous disease. A key discovery of the study is the potential pathological link between autoimmune bullous disease and interstitial lung disease. CONCLUSION: This research, one of the first comprehensive studies on autoimmune bullous disease in China, underscores the need for targeted healthcare strategies and further investigation into autoimmune bullous disease, particularly its relationship with interstitial lung disease.

Alteration of reactive oxygen species master transcription factor Nrf2 in keratinocytes exposed to monoclonal pathogenic antibody AK23 against desmoglein-3 in pemphigus vulgaris.

Keratinocytes in mucosal and skin tissues maintain tissue integrity via desmosomes and desmoglein-3 (Dsg3). Pemphigus Vulgaris (PV) is a life-threatening autoimmune blistering disease characterized by autoantibodies against Dsg3, disrupting desmosomes. Nuclear factor erythroid 2-related factor 2 (Nrf2) regulates oxidative stress responses crucial for skin tissue protection. Although the pathogenesis of PV is known, the detailed molecular events remain unclear. This study investigates changes in Nrf2 expression in keratinocytes following pathogenic anti-Dsg3 antibody AK23 exposure, using dose- and time-dependent studies employing immunofluorescence analysis. N/TERT keratinocytes were cultured in keratinocytes serum-free medium and treated with AK23 at varying doses (5 µg/mL,40µg/mL,75µg/mL) and durations (2, 6, 24 h). Immunofluorescence staining was performed to assess the expression of Nrf2 and Dsg3. All fluorescent images were analyzed using ImageJ software. A dose-dependent increase in Dsg3 was noted following AK23 treatment, while Nrf2 expression and subcellular localization varied. Time-course analyses showed decreased Nrf2 at 24 h and increased Dsg3 levels. Early time-point (2 and 6 h) variations were evident in Nrf2 levels. This study highlights the impact of AK23 on Nrf2 expression, potentially disrupting Nrf2-mediated cytoprotection and implicating oxidative stress (ROS generation) in PV pathogenesis. Further investigation is necessary to validate the findings.

Immunostimulatory effects of Toll-like receptor ligands as adjuvants in establishing a novel mouse model for pemphigus vulgaris.

BACKGROUND: The meticulous selection of appropriate vaccine adjuvants is crucial for optimizing immune responses. Traditionally, pemphigus vulgaris (PV), an autoimmune disorder, has been modelled using complete Freund's adjuvant (CFA). In this study, we aimed to discern potential variations in immune responses elicited by Toll-like receptor (TLR) ligands as compared to CFA. METHODS: A comprehensive investigation was conducted, comparing the effects of these adjuvants in conjunction with ovalbumin or desmoglein-3. Flow cytometry was employed to analyse distinct cell subsets, while enzyme-linked immunosorbent assay quantified antigen-specific antibodies and cytokine levels. Histological examination of harvested skin tissues and transcriptome analysis of skin lesions were performed to identify differentially expressed genes. RESULTS: TLR ligands demonstrated efficacy in inducing PV-like symptoms in wild-type mice, in contrast to CFA. This underscored the substantial impact of the adjuvant on self-antigen tolerance. Furthermore, we proposed an enhanced method for establishing a PV model through adoptive transfer, substituting CFA with TLR ligands. Our results revealed that in contrast to the perception that CFA being the most potent immunopotentiator reported, CFA promoted regulatory T cells (Treg), follicular regulatory T cells and IL-10-producing neutrophils, whereas TLR ligands downregulated CCL17 and IL-10. This suggested potential implications for the recruitment and activation of Treg subsets. While B cell and CD8+ T cell responses exhibited similarity, CFA induced less activation in dendritic cell subsets. A novel mouse model of PV and systemic comparison of immunostimulatory effects of adjuvants were provided by this study. CONCLUSIONS: The systematic comparison of CFA and TLR ligands shed light on the distinctive properties of these adjuvants, presenting innovative mouse models for the investigation of pemphigus. This study significantly contributes to adjuvant research and advances our understanding of PV pathogenesis. KEY POINTS/HIGHLIGHTS: Immunization with desmoglein 3 and Toll-like receptor (TLR) ligands effectively induces pemphigus symptoms in wild-type mice, whereas complete Freund's adjuvant (CFA) fails. TLR ligands heightened the autoreactivity of donor cells in the adoptive transfer pemphigus model. CFA promoted regulatory T cells and IL-10-producing neutrophils, whereas TLR ligands downregulated CCL17 and IL-10, leading to more effective immune responses.

Pulmonary interstitial lesions in pemphigus mouse model: Verifying pemphigus may not be only limited to skin and mucosa.

Interstitial lung disease (ILD) has been identified as a prevalent complication and significant contributor to mortality in individuals with pemphigus. In this study, a murine model of pemphigus was developed through the subcutaneous administration of serum IgG obtained from pemphigus patients, allowing for an investigation into the association between pemphigus and ILD. Pulmonary interstitial lesions were identified in the lungs of a pemphigus mouse model through histopathology, RT-qPCR and Sircol assay analyses. The severity of these lesions was found to be positively associated with the concentration of IgG in the injected serum. Additionally, DIF staining revealed the deposition of serum IgG in the lung tissue of pemphigus mice, indicating that the subcutaneous administration of human IgG directly impacted the lung tissue of the mice, resulting in damage. This study confirms the presence of pulmonary interstitial lesions in the pemphigus mouse model and establishes a link between pemphigus and ILD.

Pemphigus vulgaris in association with human immunodeficiency virus infection: A management dilemma.

The association of immunobullous disorders with human immunodeficiency virus (HIV) infection is rare. Concurrence of these two conditions poses a therapeutic challenge as both cause immune dysregulation. We report pemphigus vulgaris in association with HIV infection in a 50-year-old woman who died of sepsis after receiving high-dose corticosteroids for the treatment of pemphigus vulgaris.

Correlation between serum cardiac troponin I level and PDAI score in patients with pemphigus vulgaris.

Pemphigus vulgaris (PV) is a rare, yet serious autoimmune disorder primarily affecting the skin and mucous membranes. While the dermatological and mucosal aspects of PV are well-documented, the potential for systemic involvement, particularly cardiac complications, remains under-explored. This study aimed to investigate the serum cardiac troponin I (cTnI) level in patients with PV versus healthy controls. The relationship between serum cardiac troponin I (cTnI) levels and various demograpgics, clinical and laboratory characteristics in patients with PV was also dealt with. This cross-sectional study was conducted on 59 patients with pemphigus vulgaris and 59 age- and sex- matched healthy controls, visited at a tertiary care hospital from August 2021 to May 2023. After thorough history taking and physical examination, troponin level was measured by the ECL (Electrochemiluminescence) method. The correlation between serum cTnI level and various variables was evaluated using Pearson's correlation coefficient. The mean serum cardiac troponin I (cTnI) level in patient group was 0.104 ± 0.05 ng/mL, with a range of 0.01 to 0.25 ng/mL. Despite mean cTnI level in patients was greater than controls, this difference was not reach to the significance level (P value: 0.058). The analysis revealed a significant positive correlation (r = 0.52, p = 0.005310), suggesting that higher PDAI scores were associated with elevated cTnI level. The correlation between serum cardiac troponin I (cTnI) level and PDAI score, even without any clinical sign or risk factor for cardiovascular disease suggests a potential link between the severity of PV and subtle cardiac involvement, highlighting the importance of cardiac monitoring in these patients.

Pemphigus vulgaris and mucous membrane pemphigoid: A systematic review of clinical manifestations, diagnosis, and treatment.

Pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP) are mucocutaneous autoimmune diseases characterized by blistering lesions of mucous membranes and skin, with very similar clinical manifestations. This study aimed to systematically review the literature on the clinical and demographic profile, diagnostic methods, and treatment of patients with pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP). Studies describing cases of PV and MMP diagnosed by direct immunofluorescence that exhibited intraoral manifestations were included. Thirty-two articles were included, with 18 studies on PV and 15 on MMP, corresponding to 50 and 123 cases diagnosed as PV and MMP, respectively. Most patients with PV (64 %) and MMP (81.3 %) were women in the fifth and sixth decade of life, respectively. The mouth was the primary site of involvement both in PV (71.4 %) and in MMP (91 %). The cheek mucosa and gingiva were the most frequently affected intraoral sites in PV (30 %) and MMP (64.2 %), respectively. Direct immunofluorescence was positive for IgG in all cases of the two conditions. The treatment of choice was systemic corticosteroid therapy for patients with PV (50 %) and topical treatment for patients with MMP (53.7 %). Differences in intraoral site predilection, extraoral involvement, and the results of diagnostic tests allow us to trace the clinical, demographic, and diagnostic profile of PV and MMP that contributes to differential diagnosis and therapeutic management.

Exploring the role of vitamin D-VDR pathway in pemphigus foliaceous: a novel perspective on disease pathogenesis.

Several auto-immune diseases have been linked to vitamin D deficiency as a contributing environmental factor. Its pleiotropic effects on the immune system, especially its essential role in maintaining immune tolerance, make the vitamin D pathway of great interest. In this study, we focused on Pemphigus foliaceous (PF) in Tunisian population. we aimed to quantify the Serum 25[OH]D levels using chemiluminescence assay and to analyze the differential expression of the VDR, CYP27B1 and CYP24A1 genes in the circulating blood cells and lesional skin tissue of PF patients using Q-PCR. A genetic explanation was then sought to explore any direct relationship between tag polymorphisms and the inherited features of PF. Results confirmed a vitamin D hypovitaminosis in Tunisian PF patients. Interestingly, a differential gene expression correlated to the disease stratification was noted. Indeed, at the systemic level, an upregulation of VDR and CYP27B1 genes was observed in healthy controls compared to PF patients. Notably, in lesional skin tissue, the clinical and serological remission phase was correlated with high transcriptional levels of the VDR gene and conversely a drop in expression of the CYP24A1 gene. Genetic analysis indicated the involvement of the most appealing polymorphisms, rs2228570 and poly (A) microsatellite, in PF etiopathogenesis. Indeed, CAC13 haplotype was associated with a higher risk of PF development. Our findings suggest that alterations in the vitamin D-VDR pathway may influence PF physiopathology, making this pathway a potential target for pharmacological modulation, especially for cortico-resistant PF patients.

Gut Microbiome Dysbiosis in Patients with Pemphigus and Correlation with Pathogenic Autoantibodies.

BACKGROUND: Pemphigus is a group of potentially life-threatening autoimmune bullous diseases induced by pathogenic autoantibodies binding to the surface of epidermal cells. The role of the gut microbiota (GM) has been described in various autoimmune diseases. However, the impact of the GM on pemphigus is less understood. This study aimed to investigate whether there was alterations in the composition and function of the GM in pemphigus patients compared to healthy controls (HCs). METHODS: Fecal samples were collected from 20 patients with active pemphigus (AP), 11 patients with remission pemphigus (PR), and 47 HCs. To sequence the fecal samples, 16S rRNA was applied, and bioinformatic analyses were performed. RESULTS: We found differences in the abundance of certain bacterial taxa among the three groups. At the family level, the abundance of Prevotellaceae and Coriobacteriaceae positively correlated with pathogenic autoantibodies. At the genus level, the abundance of Klebsiella, Akkermansia, Bifidobacterium, Collinsella, Gemmiger, and Prevotella positively correlated with pathogenic autoantibodies. Meanwhile, the abundance of Veillonella and Clostridium_XlVa negatively correlated with pathogenic autoantibodies. A BugBase analysis revealed that the sum of potentially pathogenic bacteria was elevated in the AP group in comparison to the PR group. Additionally, the proportion of Gram-negative bacteria in the PR group was statistically significantly lower in comparison to the HC group. CONCLUSION: The differences in GM composition among the three groups, and the correlation between certain bacterial taxa and pathogenic autoantibodies of pemphigus, support a linkage between the GM and pemphigus.

Activity of apremilast in a patient with severe pemphigus vulgaris: case report.

Introduction: Although the treatment for pemphigus vulgaris (PV) has been revolutionized by the use of rituximab combined with corticosteroids, new effective therapies with a better safety profile are needed. Observation: A 67-year-old woman was diagnosed with severe mucosal PV, which was initially misdiagnosed as atypical Behçet's disease. Following an unsuccessful colchicine treatment, significant improvement was observed upon the introduction of apremilast: reduced pain, fewer lesions, and a stabilized weight. The discontinuation of apremilast led to a rapid relapse. Retrospective analysis through anti-Dsg3 ELISA indicated a gradual decrease in antibody levels during the apremilast treatment. Discussion: Apremilast, a phosphodiesterase 4 inhibitor approved for psoriasis and Behçet's disease's related oral ulcers treatment, demonstrated its efficacy in this PV case. This is the second case report highlighting the effectiveness of apremilast for PV treatment. Apremilast's ability to upregulate cyclic adenosine monophosphate (cAMP) levels appears to contribute to the stabilization of keratinocyte adhesion. Conclusion: Apremilast may be a promising therapeutic option for the treatment of pemphigus, with an innovative mechanism of action, no induced immunosuppression, and good tolerance. It could be a good alternative to steroids, in the treatment regimen of steroids combined with rituximab.

A Case of an Autoimmune Blistering Disease: Pemphigus Vulgaris.

Pemphigus vulgaris is a rare autoimmune disorder characterized by the formation of intraepithelial blisters that clinically appear as erosions and flaccid bullae on the skin and mucus membranes. Herein, we report a case of pemphigus vulgaris in an elderly male. He was initially misdiagnosed by his primary care provider and given topical lidocaine and acetaminophen with hydrocodone, without improvement in symptoms. This delay in treatment caused a worsening of his condition. The patient presented to our dermatology office two months after his primary care visit and reported worsening blisters and pain. Clinically he presented with flaccid bullae, crusted erosions, and erythematous plaques on the chest, back, abdomen, arms, and legs, and a tender oral ulcer. Two punch biopsies were obtained and sent for direct immunofluorescence and routine histology. The biopsy results confirmed the diagnosis of pemphigus vulgaris. Our patient achieved clearance after four weeks of oral prednisone and maintained clearance after a slow prednisone taper and the addition of mycophenolate mofetil 1g twice daily. We aim to bring awareness of the clinical presentation and treatment regimen of pemphigus vulgaris to prevent misdiagnosis and delayed care.

Pemphigus Vulgaris Treated With Ibrutinib: A Case Report.

Pemphigus vulgaris (PV) stands as a rare autoimmune disorder characterized by blistering and erosion of mucocutaneous membranes. The pathogenesis of PV implicates both B and T cells, which target cell-to-cell adhesion molecules within the epithelia of the skin and oral mucosa, leading to acantholysis. Typically, the presentation involves blistering of the oral mucosa, often followed by cutaneous lesions. Given the considerable risk of morbidity and mortality associated with PV, early diagnosis is crucial, typically relying on a combination of clinical features, histopathology, and direct immunofluorescence. Bruton tyrosine kinase (BTK) plays a significant role in the pathophysiology of autoimmune diseases and inflammation. Herein, we present a case of PV that demonstrated resistance to first-line therapy with steroids. Subsequently, treatment with the BTK inhibitor ibrutinib was initiated, yielding favorable outcomes. This case underscores the potential of targeted therapies, such as BTK inhibitors, in managing PV refractory to conventional treatment modalities.

Serum interleukin-6 concentration in patients with pemphigus.

Pemphigus is a rare blistering autoimmune disease that damages the integumentary system and lowers the quality of life of patients. Interleukin-6 (IL-6) has been linked to the immunopathogenesis of pemphigus, according to recent research. Thus, the investigation purpose was to assess the function of IL-6 in the development and intensity of pemphigus disease. Between January 2022 and August 2022, a case-series study involving 26 patients with pemphigus vulgaris (PV), four patients with pemphigus foliaceus (PF), and 20 healthy volunteers was carried out at the Ho Chi Minh City Hospital of Dermato-Venereology. Patients with PV and PF had significantly higher serum IL-6 concentrations than healthy volunteers (p<0.001). Patients with a positive Nikolsky sign had significantly higher serum IL-6 concentrations than those with a negative sign (p<0.001). The serum IL-6 concentration and the pemphigus disease area index were found to significantly correlate (r=0.8, p<0.001). According to our findings, IL-6 might be a significant factor in pemphigus development and severity. Thus, novel treatments that specifically target IL-6 could be a good option for managing pemphigus, particularly in its more severe forms.

Distorted frequency and functionality of natural killer cells in pemphigus vulgaris: A potential therapeutic target.

Pemphigus vulgaris (PV) is a rare autoimmune disorder where autoantibodies target the desmosomal proteins resulting in blistering of oral mucosa and skin. While the pathogenesis of PV is mainly mediated by the adaptive immune system, key players of innate immunity are also emerging. This study outlines the phenotypic as well as functional attributes of NK cells in PV. Through in-depth analysis using flow cytometry we identified an increase in the frequency of CD56+ CD3- NK cells and their subtypes in periphery. Along with this there is an increased frequency of IFNγ+ CD56bright CD16dim NK cells. mRNA expression of sorted NK cells for differentially expressed genes, particularly key transcription factors such as T-bet and EOMES, as well as surface receptors like NKG2D and KIR2D, and the cytokine IFNγ, displayed significant upregulation. A significant activation of NK cells was seen in the disease state. The levels of perforin and IFNγ were significantly elevated in the culture supernatants of patients. Additionally, a significantly higher cytotoxicity of NK cells in PV was observed. In lesioned tissues of PV, NK related markers were significantly increased. Lastly, we observed NK cells using confocal microscopy in the tissue biopsies of patients which showed significant infiltration of CD56+ CD3- NK cells at the lesional sites. This study aimed to shed light on the pivotal role of NK cells in the immunopathology of PV, offering a thorough understanding of their behaviour and changes in expression which might help in contributing to the development of novel therapeutics.

Utility of C4d Immunohistochemistry in the Diagnosis of Esophageal Pemphigus Vulgaris.

Aims. To assess the utility of C4d immunohistochemistry for esophageal pemphigus vulgaris. Methods and results. We searched for patients with a history of esophageal pemphigus vulgaris who had esophageal biopsies for routine hematoxylin and eosin (H&E) staining. A total of 8 biopsies from 7 patients were available. We also identified 18 non-pemphigus esophageal biopsies for controls. C4d immunohistochemistry was performed on each biopsy. Five of 6 (83%) biopsies with classic pemphigus vulgaris histologic findings were positive for intercellular staining at the basal layer. The negative biopsy was in a patient that had recently received high-dose corticosteroid treatment for a flare. Two biopsies with atypical histologic features for pemphigus vulgaris had negative C4d staining but positive direct immunofluorescence (DIF) studies. Various nonspecific C4d staining patterns were observed in the controls, but none showed the intercellular staining pattern that was observed in pemphigus vulgaris. Conclusions. Suprabasal clefting with acantholysis and "tombstone effect" are described histologic features of pemphigus vulgaris on H&E. However, procedural artifact may mimic these findings. Currently, the gold standard for pemphigus vulgaris is DIF, which is not always available because it cannot routinely be performed on formalin-fixed paraffin embedded tissue. Our study shows that C4d immunohistochemistry may be a useful adjunct in evaluating esophageal pemphigus vulgaris.

Biomarkers in Pemphigus Vulgaris: A Systematic Review.

INTRODUCTION: Pemphigus vulgaris (PV) is a rare intraepidermal blistering disease that is potentially life-threatening due to risk of infection and failure of skin barrier function. The identification of biomarkers has the potential to provide diagnostic utility and identify new therapeutic targets. The objective of this systematic review is to identify all potentially relevant PV biomarkers, categorize them, and identify trends to determine the involvement of T-cell-mediated, B-cell-1mediated, and innate immune-mediated pathways in PV pathogenesis. METHODS/RESULTS: Medline and Embase databases were searched according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, resulting in the inclusion of 66 studies that reported on a total of 2463 patients and 146 unique biomarkers. Biomarkers were categorized into T-cell-mediated, B-cell-mediated, and innate immune system pathways. The most notable biomarkers trends include elevations in IL-4, IL-6, IL-17A, anti-Dsg1/3 autoantibodies, and a reduction in Treg cells and FOXP3. CONCLUSION: The results of this review support current theories of PV pathogenesis, with increased Th2 activity, increased Th17 activity, decreased Treg activity, and production of anti-Dsg1/3 autoantibodies being observed. Targeting of IL-4 and IL-6 may provide therapeutic benefit. However, more research is required to validate biomarkers for clinical utility and assess viability as therapeutic targets.