Single-cell sequencing reveals distinct immune cell features in cutaneous lesions of pemphigus vulgaris and bullous pemphigoid

Bullous pemphigoid (BP) and pemphigus vulgaris (PV) are two common subtypes of autoimmune bullous disease (AIBD). The key role of circulating autoreactive immune cells contributing to skin damage of AIBD has been widely recognized. Nevertheless, the immune characteristics in cutaneous lesions remain unclear. Here, we performed single-cell RNA sequencing (scRNA-seq) and single-cell VDJ sequencing (scRNA-seq) to generate transcriptional profiles for cells and T/B cell clonetype in skin lesions of BP and PV. We found that the proportions of NK&T, macrophages/ dendritic cells, B cells, and mast cells increased in BP and PV lesions. Then, BP and PV cells constituted over 75% of all myeloid cell subtypes, CD4+ T cell subtypes and CD8+ T cell subtypes. Strikingly, CD8+ Trm was identified to be expanded in PV, and located in the intermediate state of the pseudotime trajectory from CD8+ Tm to CD8+ Tem. Interestingly, CD8+ Tem and CD4+ Treg highly expressed exhaustion-related genes, especially in BP lesions. Moreover, the enhanced cell communication between stromal cells and immune cells like B cells and macrophages/ dendritic cells was also identified in BP and PV lesions. Finally, clone expansion was observed in T cells of BP and PV compared with HC, while CD8+ Trm represented the highest ratio of hyperexpanded TCR clones among all T cell subtypes. Our study generally depicts a large and comprehensive single-cell landscape of cutaneous lesions and highlights immune cell features in BP and PV. This offers potential research targets for further investigation.

Pharyngeal Ulcer as the First Sign of Pemphigus

Pemphigus is a rare autoimmune mucocutaneous bullous disease that can be life-threatening. We report a case of pemphigus vulgaris with pharyngeal ulcer as the initial presentation that was treated with glucocorticoid therapy.

Concordance of clinical, histopathologic and direct Immunofluorescence findings in patients with intraepidermal immunobullous disorders

Objective

To determine the concordance among clinical, histopathological and immunofluorescence as diagnostic methods for intraepidermal immunobullous disorders.

METHODS

The prospective cross-sectional study was conducted at the Institute of Skin Diseases, Karachi, from December 2020 to December 2022, and comprised adult patients of either gender presenting with complaints of bullae, vesicles, pustules and crusts on the skin or mucous membrane. Diagnostic findings of each patient as obtained by clinical assessment, microscopy and direct immunofluorescence were compared. Data was analysed using SPSS 19.

RESULTS

Of the 81 patients, 41(50.6%) were males and 40(49.4%) were females. The overall median age was 35 years (interquartile range: 23 years), with 66(75%) patients aged 19-55 years. The predominant body site involved was the trunk 49(60.5%), followed by mucosa 26(32.1%). Clinical diagnosis detected 80(98.7%) cases, compared to 76(93.8%) by microscopy and 81(100%) by direct immunofluorescence.

Conclusion

Direct immunofluorescence was found to be the gold standard for a confirmatory diagnosis of intraepidermal immunobullous disorders, especially when clinical and histopathology findings were inconclusive.

Demonstration of direct immunofluorescence on three substrates in a case of pemphigus

Direct immunofluorescence (DIF) on skin is considered as the gold standard in the diagnosis of pemphigus. However, alternate substrates can be used. We demonstrate DIF on three substrates, skin biopsy specimen, anagen hair and scrapings of oral erosions. Collection of alternative substrates can be more acceptable to young patients as it is less invasive. It may also be used to detect relapses in cases of pemphigus.

Immune-mediated oral mucosal pathology: a comprehensive review and update for clinicians - part II

The oral mucosa can be involved in a wide variety of mucocutaneous conditions that may present primarily in the mouth or affect other cutaneous or mucosal sites. Many of these conditions are immune mediated and typically present as inflammatory mucosal pathology. Patients experiencing such conditions usually seek medical evaluation and treatment due to the associated pain and discomfort, and occasionally taste disturbance or dysphagia and the overall deterioration in the oral health-related quality of life. These conditions share some common features and there could be some overlap in their clinical presentation, which can lead to delays in diagnosis and proper management of patients. Clinicians dealing with such disorders, including dermatologists, need to be aware of the oral manifestations of mucocutaneous conditions, their clinical features, underlying mechanisms, diagnostic approaches, and treatment options, as well as the recent advances in the research on these conditions. This review provides a comprehensive, evidence-based reference for clinicians, with updated insights into a group of immune mediated conditions known to cause oral mucosal pathology. Part one will cover oral lichen planus, erythema multiforme and systemic lupus erythematosus, while part two will cover recurrent aphthous stomatitis, pemphigus vulgaris and mucous membrane pemphigoid, in addition to the less common disorders linear IgA disease, dermatitis herpetiformis and epidermolysis bullosa.

Adalimumab induced exacerbation of psoriasis in patients with combined pemphigus: A case report

RATIONALE

Psoriasis is an immune-related disease caused by genetic factors, abnormalities in the immune system and environmental factors, while pemphigus is an autoimmune disease caused by the autoimmune system attacking the skin and mucosal tissues. Herein, we aimed to report a rare case of adalimumab induced exacerbation of psoriasis patients with pemphigus. The rare disease causes considerable challenges for clinical diagnosis and treatment.

PATIENT CONCERNS

The patient was a 43-year-old man with intermittent erythema and scaling all over the body for more than 20 years, and blisters and vesicles on the trunk and limbs for 1 month. Half a year ago, the patient had blisters on the limbs, and was diagnosed with deciduous pemphigus in a hospital, and the blisters subsided after being given traditional Chinese medicine orally. Half a month ago, the erythema area was enlarged, and adalimumab 80 mg intramuscular injection was given for 1 time after consultation in the hospital. On the following day, the area of erythema and scales was suddenly enlarged obviously compared with the previous 1, and obvious blisters and vesicles appeared on the limbs, neck, and trunk, which were aggravated progressively and accompanied by obvious itching and pain.

DIAGNOSES

The patient was diagnosed with psoriasis in patients with combined pemphigus.

INTERVENTION

After combined treatment with methylprednisolone and cyclosporine, the skin lesions have basically recovered.

OUTCOMES

The skin lesions have basically healed. Follow up for 6 months without recurrence.

LESSONS

Methylprednisolone combined with cyclosporine may be an option in treating patients with psoriasis patients with pemphigus.

Pregnancy in pemphigus vulgaris: A systematic review

PROBLEM

Pemphigus vulgaris may worsen during pregnancy, leading to both maternal and fetal complications. The relationship between pemphigus vulgaris and pregnancy remains unclear, and the outcomes and treatments of pemphigus vulgaris during pregnancy have not been extensively discussed.

METHOD OF STUDY

This article systematically reviews the literature, focusing on the relationship between pemphigus vulgaris and pregnancy. We conducted comprehensive searches in PubMed, Embase, Cochrane Library, and Web of Science databases, identifying 42 studies reporting the disease course, pregnancy outcomes, and management of both pregnancy and pemphigus vulgaris.

RESULTS

A total of 57 cases were included in the analysis, categorized into three distinct forms: pemphigus vulgaris onset before pregnancy (n = 33), onset during pregnancy (n = 20), and onset during the postpartum period (n = 4). Fifty four cases reported treatment strategies, among them, 44 cases (81.5%) initially received systemic corticosteroid therapy during pregnancy. Out of these cases, 7 (15.9%) did not achieve successful remission and required alternative treatment approaches. In terms of pregnancy outcomes, 23 out of 62 neonates (37.1%) exhibited skin lesions or tested positive for anti-dsg IgG in their serum, while 16 neonates (25.8%) experienced other complications.

CONCLUSIONS

These findings highlight the importance of effectively managing pemphigus vulgaris during pregnancy to ensure optimal outcomes.

Association of Human Endogenous Retrovirus-W (HERV-W) Copies with Pemphigus Vulgaris

BACKGROUND

Pemphigus is classified as a group of chronic, recurrent, and potentially fatal bullous autoimmune diseases that leads to blisters and skin lesions resulting from IgG antibodies and the loss of cellular connections in the epidermis. Human endogenous retrovirus (HERV) sequences and their products (RNA, cytosolic DNA, and proteins) can modulate the immune system and contribute to autoimmunity. The extent to which, HERV-W env copies may be involved in the pathogenesis of pemphigus remains to be elucidated.

AIM

This study aimed to comparatively evaluate the relative levels of HERV-W env DNA copy numbers in the peripheral blood mononuclear cells (PBMCs) of pemphigus vulgaris patients and healthy controls.

METHODS

Thirty-one pemphigus patients and the corresponding age- and sex-matched healthy controls were included in the study. The relative levels of HERV-W env DNA copy numbers were then evaluated by qPCR using specific primers, in the PBMCs of the patients and controls.

RESULTS

Our results indicated that relative levels of HERV-W env DNA copy numbers in the patients were significantly higher than that in the controls (1.67±0.86 vs. 1.17±0.75; p = 0.02). There was also a significant difference between the HERV-W env copies of male and female patients (p = 0.001). Furthermore, there was no relationship between the HERV-W env copy number and disease onset (p = 0.19) . According to the obtained data, we could not find any relationship between the HERV-W env copy number and serum Dsg1(p=0.86) and Dsg3 (p=0.76) levels.

CONCLUSION

Our results indicated a positive link between the HERV-W env copies and pathogenesis of pemphigus. The association between clinical severity score and HERVW env copies in the PBMCs as a biomarker for pemphigus needs further studies.

A case of herpetiform pemphigus mimicking bullous pemphigoid after using secukinumab and successfully treated with sulfasalazine

Interleukin 17A (IL-17A) inhibitors, such as secukinumab, have been widely used as the mainstream treatment for chronic plaque psoriasis; however, cutaneous adverse events have been reported. Here, we report a 43-year-old Chinese man who developed herpetiform pemphigus (HP) during secukinumab treatment for his psoriasis. He presented with (1) clinical features of HP, which resembled bullous pemphigoid; histopathological features of intraepidermal blisters, eosinophilic/neutrophilic spongiosis, and liquefactive degeneration of the basal cell layer; (3) positive anti-desmoglein 1 antibody by enzyme-linked immunosorbent assay and cell surface IgG reactivity within the epidermis by indirect immunofluorescence assay; and (4) a satisfactory response to salicylazosulfapyridine (sulfasalazine). To the best of our knowledge, this is the first report of the development of HP after the use of secukinumab for psoriasis.

A case report of esophageal cancer in a patient with pemphigus vulgaris: A coincidence or something beyond that?

BACKGROUND

Pemphigus is a group of rare but serious autoimmune blistering disorders, affecting skin and mucus membrane. Different reports have been published in respect to the coexistence of pemphigus with neoplasms, especially lympho-proliferative ones.

CASE

Here, we have reported a patient previously diagnosed with pemphigus vulgaris (PV) who developed esophageal squamous cell carcinoma (SCC).

CONCLUSION

Dyspepsia and dysphagia in patients with PV might not be merely due to pemphigus erosions or simply an adverse effect of systemic corticosteroid such as irritant or candidal esophagitis and should raise the suspicion of more serious conditions in case of resistant symptoms without appropriate response to treatment.

Two cases of cutaneous-type pemphigus vulgaris and a case of pemphigus foliaceus without mucosal involvement despite high anti-desmoglein 3 autoantibody levels

Pemphigus is an autoimmune blistering disease with two major subtypes, pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Although most patients with PV show oral lesions, cutaneous type PV (C-PV) is a rare subtype clinically characterized by predominant cutaneous involvement with no or subtle mucosal lesions. Patients with PF present with only skin involvement; they do not have mucosal lesions. Serologically, autoantibodies against desmoglein (Dsg) 3 and Dsg1 are observed in C-PV whereas PF is associated with anti-Dsg1 antibodies only. Herein, we describe three cases of pemphigus presenting with predominant skin lesions and no mucosal involvement despite high anti-Dsg 3 autoantibody levels in chemiluminescent enzyme immune assays (CLEIAs). In addition, anti-Dsg 1 autoantibodies were positive in patients 2 and 3, but negative in patient 1 based on CLEIAs. Histological examination of the skin showed suprabasal acantholysis in patients 1 and 2, and blister formation in the upper epidermis in patient 3. Histopathology of the oral membrane in patients 1 and 2 showed subtle acantholysis in the suprabasal layer. Thus, we diagnosed patients 1 and 2 as having cutaneous type PV and patient 3 as having PF. Ethylenediaminetetraacetic acid-treated enzyme-linked immunosorbent assay demonstrated a low proportion of anti-Dsg3 autoantibodies recognizing Ca2+ -dependent epitopes, antibodies against which are thought to be the main contributor to acantholysis. Thus, along with Dsg1 antibodies, weak anti-Dsg3 antibodies could induce acantholysis in the skin, but they are insufficient to induce mucosal lesions.

Is transition between subtypes of pemphigus possible? A series of pemphigus vulgaris patients showing the transition to pemphigus foliaceus

BACKGROUND

Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are subtypes of pemphigus with distinct clinical and laboratory features. The transition between these two subtypes has rarely been reported previously.

METHODS

The data of PV patients who exhibited clinical and immunoserological transition to PF during the follow-up period were retrospectively evaluated regarding their demographical, clinical, and laboratory characteristics.

RESULTS

Among 453 patients diagnosed with PV, 13 (2.9%) patients exhibited clinical and immunoserological transition from PV to PF. The mean age of PV patients at the time of diagnosis was 39.8 ± 14.7 (19‒62) years and 7 (53.8%) of them were female. These patients showed clinical and immunoserological transition from PV to PF after a period ranging from 4 months to 13 years (mean 36.2 ± 41 months). In addition to typical clinical features of PF, all patients had positive anti-desmoglein-1 and negative anti-desmoglein-3 antibody levels after the clinical transition had occurred without any mucosal involvement. During a mean 7.8 ± 5.8 (2‒21) years of follow-up period after the transition from PV to PF, only one female patient had experienced a re-transition to PV characterized by a relapse of disease involving mucosal surfaces with positive anti-desmoglein-3 antibody levels following a 5-year period of remission period without treatment.

STUDY LIMITATIONS

Single-center study with a retrospective study design.

CONCLUSION

Our series is the largest group of patients reported to show the transition from PV to PF to date with a long follow-up period. The reason behind the disappearance of anti-desmoglein-3 antibodies and the pathogenesis of this phenomenon is not yet elucidated.

[The main autoimmune bullous diseases]

Autoimmune bullous diseases are disorders in which the immune system mistakenly attacks certain molecules that act as "glue" in the various layers of the skin, leading to the formation of bullae or vesicles. A bulla is a liquid-containing lesion over five millimeters in size on the skin or mucous membranes. It forms due to a loss of cohesion between the epidermis and dermis, or between keratinocytes within the epidermis. Diagnosis is based on biopsies, which show the presence of autoantibodies and the depth of skin detachment. A blood test can be used to identify circulating autoantibodies.

Current biologics in treatment of pemphigus foliaceus: a systematic review

Background

Pemphigus foliaceus (PF) differs from pemphigus vulgaris (PV) in that it affects only the skin and mucous membranes are not involved. Pemphigus is commonly treated with systemic corticosteroids and immunosuppressive agents (ISAs). More recently, biologics have been used. The current literature on biologic therapy often combines treatment of PF with PV, hence it is often difficult for clinicians to isolate the treatment of PF from PV. The purpose of this review was to provide information regarding the use of current biological therapy, specifically in PF.

Materials and methods

A search of PubMed, Embase, and other databases was conducted using keywords pemphigus foliaceus (PF), rituximab (RTX), intravenous immunoglobulin (IVIg), and biologics. Forty-one studies were included in this review, which produced 105 patients with PF, treated with RTX, IVIg, or a combination of both. Eighty-five patients were treated with RTX, eight patients with IVIg, and 12 received both RTX and IVIg.

Results

Most patients in this review had PF that was nonresponsive to conventional immunosuppressive therapies (CIST), and had significant side effects from their use. RTX treatment resulted in complete remission (CR) in 63.2%, a relapse rate of 39.5%, an infection rate of 19.7%, and a mortality rate of 3.9%. Relapse was greater in the lymphoma (LP) protocol than the rheumatoid arthritis (RA) protocol (p<0.0001). IVIg led to CR in 62.5% of patients, with no relapses or infections. Patients receiving both biologics experienced better outcomes when RTX was first administered, then followed by IVIg. Follow-up durations for patients receiving RTX, IVIg, and both were 22.1, 24.8, and 35.7 months, respectively.

Discussion

In pemphigus foliaceus patients nonresponsive to conventional immunosuppressive therapy or in those with significant side effects from CIST, RTX and IVIg appear to be useful agents. Profile of clinical response, as well as relapse, infection, and mortality rates in PF patients treated with RTX were similar to those observed in PV patients. The data suggests that protocols specific for PF may produce better outcomes, less adverse effects, and improved quality of life.

ODSS vs. ABSIS and PDAI oral parts in pemphigus vulgaris: inter-rater reliability and testing times

OBJECTIVES

The existence of standard methods for diagnosis and measuring the severity of diseases leads to a more accurate severity assessment, the possibility of following up, and the possibility of comparing the results of studies. This study aimed to compare different pemphigus vulgaris (PV) assessment methods regarding inter-observer reliability and testing times-focusing on oral parts.

MATERIALS AND METHODS

Two dermatologists evaluated orally involved PV patients by oral parts of Autoimmune Bullous Skin Disorder Intensity Score (ABSIS), Pemphigus Disease Area Index (PDAI), and Oral Disease Severity Score (ODSS).

RESULTS

Seventy patients completed the study. The intraclass correlation coefficient showed the evaluators' agreements on ABSIS, PDAI, and ODSS with 0.98, 0.94, and 0.95, respectively. Reliability analyses showed near-perfect relationships between each scoring methods pairs. There was no association between lesion sites and disease severity. The PDAI scoring duration was significantly shorter, and the ABSIS scoring duration was significantly longer.

CONCLUSION

ODSS is valid for evaluating oral involvement in patients with PV and relates to ABSIS and PDAI almost perfectly. Besides, it was shown that the evaluation of patients' oral involvement based on PDAI and ODSS is done in about 1 min, which seems clinically reasonable.

Immune-mediated oral mucosal pathology: a comprehensive review and update for clinicians. Part I

The oral mucosa can be involved in a wide variety of mucocutaneous conditions that may present primarily in the mouth or affect other cutaneous or mucosal sites. Many of these conditions are immune mediated and typically present as inflammatory mucosal pathology. Patients experiencing such conditions usually seek medical evaluation and treatment due to the associated pain and discomfort and occasionally taste disturbance or dysphagia and the overall deterioration in the oral health-related quality of life. These conditions share some common features and there could be some overlapping in their clinical presentation, which can lead to delays in diagnosis and proper management of patients. Clinicians dealing with such disorders, including dermatologists, need to be aware of the oral manifestations of mucocutaneous conditions, their clinical features, underlying mechanisms, diagnostic approaches, and treatment options, as well as the recent advances in the research on these conditions. This review provides a comprehensive, evidence-based reference for clinicians, with updated insights into a group of immune mediated conditions known to cause oral mucosal pathology. Part one will cover oral lichen planus, erythema multiforme and systemic lupus erythematosus, while part two will cover pemphigus vulgaris and mucous membrane pemphigoid, recurrent aphthous stomatitis, in addition to the less common disorders linear IgA disease, dermatitis herpetiformis and epidermolysis bullosa.

Efficacy of anti-desmoglein 1 and anti-desmoglein 3 levels by enzyme-linked immunosorbent assay compared to biopsy of chronic oral ulcerative diseases with positive Nikolsky's sign to diagnose oral pemphigus vulgaris with or without skin involvement: a retrospective institutional observational pilot study

OBJECTIVE

We assessed the efficacy of anti-desmoglein 1 (anti-DSG1) and anti-DSG3 levels by enzyme-linked immunosorbent assay (ELISA) as a preliminary diagnostic test in the diagnosis of oral pemphigus vulgaris (OPV) with or without skin involvement compared to biopsy.

STUDY DESIGN

We retrospectively analyzed data collected from 23 patients (mean age 45.13 years) who had presented with chronic oral ulcerations, desquamative gingivitis, and a positive Nikolsky's sign. We performed ELISA, histopathologic examination, and direct immunofluorescence (DIF) and then calculated the sensitivity and specificity of the results of ELISA, histopathology, DIF, and the presence of a positive Nikolsky's sign in diagnosis.

RESULTS

The ELISA results showed that 18 patients had elevated anti-DSG3 levels, of whom 8 also had elevated anti-DSG1 levels. The histopathology results indicated that 18 patients had OPV, of whom 4 had oral lichen planus, and 1 had sub-epithelial blistering disease confirmed to be mucous membrane pemphigoid MMP by DIF. ELISA, histopathology, and DIF had a 100% sensitivity and specificity, and the presence of a positive Nikolsky's sign had a sensitivity and specificity of 100% and 78.26%, respectively.

CONCLUSIONS

Measurement of anti-DSG1 and anti-DSG3 levels by ELISA warrants consideration as a first-line diagnostic test for early detection of OPV with or without skin involvement over biopsy.

Cut-off values for IL-21 and IL-23 as biochemical markers for pemphigus vulgaris

Pemphigus vulgaris (PV) is a potentially fatal mucocutaneous autoimmune disease characterized by severe skin lesions. Interleukin-21 (IL-21) and IL-23 have been linked to several autoimmune inflammatory diseases that may have a critical role in PV immunopathogenesis, including T-helper 17 (Th17) development. This study aimed to compare the serum levels of IL-21 and IL-23 in patients with PV and healthy controls. This case-control study included 90 participants (45 patients and 45 controls). Serum IL-21 and IL-23 were measured using the Sandwich-ELISA method provided by Sunlong Biotech, China. The findings revealed statistically significant results for IL-21 O.D. and Conc. (p=0.012*) and highly significant results for IL-23 O.D. and Conc. (p=0.000**). Furthermore, cut-off values were established for IL-21 (O.D.=0.071 pg/mL, Conc.=6.468 pg/mL) and IL-23 (O.D.=0.141 pg/mL, Conc.=6.745 pg/mL). These results indicate a potential association between PV and IL-21, IL-23, and the identified cut-off values. The particular roles of cytokines and how they can be utilized to treat PV require more investigation. To our knowledge, this was the first study to detect a cut-off point for IL-21 and IL-23 that may be used as novel and cost-effective biochemical markers for disease diagnosis.

Interleukin-37 inhibits desmoglein-3 endocytosis and keratinocyte dissociation via upregulation of Caveolin-1 and inhibition of the STAT3 pathway

BACKGROUND

Pemphigus vulgaris (PV) is a potentially fatal autoimmune bullous disease primarily caused by acantholysis of keratinocytes attributed to pathogenic desmoglein-3 (Dsg3) autoantibodies. Interleukin-37 (IL-37) reportedly plays important roles in a variety of autoimmune diseases, but its role in PV is not clear.

OBJECTIVES

To investigate whether IL-37 plays a role in the occurrence and progression of PV.

METHODS

HaCaT keratinocytes were stimulated with anti-Dsg3 antibody to establish an in vitro PV model, which was defined as anti-Dsg3 group. Cells incubated with medium without anti-Dsg3 treatment were used as control. IL-37 was cultured with these cells infected with or without lentiviral vector shRNA-Caveolin-1 (sh-Cav-1-LV). Cell dissociation assay and immunocytofluorescence were performed to assess keratinocyte dissociation, keratin retraction and Dsg3 endocytosis. Real-time PCR was used to detect the mRNA level of Cav-1, and western blot was used to determine the protein expression of Cav-1, Dsg3, STAT3 and phosphorylated-STAT3 (p-STAT3).

RESULTS

The anti-Dsg3 group showed more cell debris, increased keratin retraction, increased Dsg3 endocytosis, reduced Cav-1 expression and co-localization than the control group, while IL-37 treatment neutralized all of these changes. Interestingly, Cav-1 knockdown supressed the inhibitory effect of IL-37 on keratinocyte dissociation and Dsg3 internalization. The protein expression of p-STAT3 was increased in keratinocytes of the PV model but decreased by IL-37. Re-activation of the STAT3 pathway by colivelin supressed the inhibitory effect of IL-37 on keratinocyte dissociation and Dsg3 internalization, along with upregulation of Cav-1 and Dsg3.

CONCLUSIONS

IL-37 inhibited keratinocyte dissociation and Dsg3 endocytosis in an in vitro PV model through the upregulating Cav-1 and inhibiting STAT3 pathway.

The human skin organ culture model as an optimal complementary tool for murine pemphigus models

Pemphigus is a severe autoimmune bullous disease of the skin and/or mucous membranes caused by autoantibodies that mainly target the adhesion proteins desmoglein (Dsg) 3 and/or Dsg1. Clinically, pemphigus is characterized by flaccid blistering, leading to severe water and electrolyte loss. Before the introduction of corticosteroid treatment, the disease turned out to be fatal in many cases. Despite recent therapeutic improvements, treatment of pemphigus patients is centred on prolonged systemic immunosuppression and remains challenging. Current drug development for pemphigus has a strong focus on disease-causing B cells and autoantibodies and, more recently, also on modulating autoantibody-induced tissue pathology and keratinocyte signalling. This drug development requires reliable pre-clinical model systems replicating the pathogenesis of the human disease. Among those are neonatal and adult mouse models based on the transfer of Dsg3, Dsg1/3 or Dsg1-specific autoantibodies. To reduce the number of animal experiments, we recently established a standardized human skin organ culture (HSOC) model for pemphigus. This model reproduces the clinical phenotype of autoantibody-induced tissue pathology in pemphigus vulgaris. For induction of blistering, a recombinant single-chain variable fragment (scFv) targeting both Dsg1 and 3 is injected into pieces of human skin (obtained from plastic surgeries). Further characterization of the HSOC model demonstrated that key morphologic, molecular and immunologic features of pemphigus are being replicated. Thus, the pemphigus HSOC model is an excellent alternative to pemphigus animal model systems that are based on the transfer of (auto)antibodies.

cAMP: A master regulator of cadherin-mediated binding in endothelium, epithelium and myocardium

Regulation of cadherin-mediated cell adhesion is crucial not only for maintaining tissue integrity and barrier function in the endothelium and epithelium but also for electromechanical coupling within the myocardium. Therefore, loss of cadherin-mediated adhesion causes various disorders, including vascular inflammation and desmosome-related diseases such as the autoimmune blistering skin dermatosis pemphigus and arrhythmogenic cardiomyopathy. Mechanisms regulating cadherin-mediated binding contribute to the pathogenesis of diseases and may also be used as therapeutic targets. Over the last 30 years, cyclic adenosine 3',5'-monophosphate (cAMP) has emerged as one of the master regulators of cell adhesion in endothelium and, more recently, also in epithelial cells as well as in cardiomyocytes. A broad spectrum of experimental models from vascular physiology and cell biology applied by different generations of researchers provided evidence that not only cadherins of endothelial adherens junctions (AJ) but also desmosomal contacts in keratinocytes and the cardiomyocyte intercalated discs are central targets in this scenario. The molecular mechanisms involve protein kinase A- and exchange protein directly activated by cAMP-mediated regulation of Rho family GTPases and S665 phosphorylation of the AJ and desmosome adaptor protein plakoglobin. In line with this, phosphodiesterase 4 inhibitors such as apremilast have been proposed as a therapeutic strategy to stabilize cadherin-mediated adhesion in pemphigus and may also be effective to treat other disorders where cadherin-mediated binding is compromised.

Pemphigus Vulgaris: More Than Just a Skin Disease

INTRODUCTION

Pemphigus is a group of autoimmune diseases of the skin and mucous membranes that is characterized by multiple bullae formation. It is caused by autoantibodies directed against the cell surface of keratinocytes, resulting in the loss of cell-cell adhesion of keratinocytes. This disease can be very debilitating and difficult to treat if large surface areas are involved.

METHODS

We performed a retrospective review of a complex case of pemphigus vulgaris in a 24-year-old man who develop partial-thickness skin lesions distributed throughout the entire body with a total body surface of 80% short after an episode of strep throat treated with amoxicillin.

RESULTS

The patient had a complicated hospital course in which the standard treatment of the disease led to adverse effects that were successfully managed at our busy burn center.

CONCLUSIONS

Pemphigus vulgaris is a complex skin disease in which treatment techniques carry their risk and must be tailored to the patient's specific needs. Treatment of this conditions at a burn center would be beneficial as demonstrated with conditions like Stevens-Johnson syndrome and toxic epidermal necrolysis.

[Senear-Usher syndrome (seborrheic pemphigus): An exceptional case]

BACKGROUND

Among the autoimmune diseases causing erosive lesions and blisters on skin and mucous membranes is pemphigus. Within this is a rare subtype known as seborrheic pemphigus or Senear-usher syndrome which is characterized by broken blisters and crusts involving the seborrheic areas.

CASE REPORT

A 40-year-old female patient, initially treated in a first level unit for a condition of 45 days of evolution, characterized by thick scabby lesions with an erythematous base, pruritic and painful, located in the center of the face, with posterior extension towards the abdomen, thorax, and extremities. Treatment consisted of prednisolone, with favorable evolution. The biopsy of the lesions with the diagnosis of seborrheic pemphigus.

CONCLUSIONS

Senear-usher syndrome is a rare disease of multifactorial origin. Early diagnosis and adequate treatment are decisive factors to avoid the evolution and advanced forms of the disease.

Histopathological Spectrum And Role Of Clinicopathological Correlation In The Diagnosis Of Vesiculobullous Lesions

BACKGROUND

Histopathology is an important diagnostic modality for vesiculobullous lesions, however the diagnosis may at times require use of Immunofluorescence techniques which are expensive and not widely available. The aim of this study was to determine the histopathological spectrum of vesiculobullous diseases and to determine the role of clinic-pathological correlation in diagnosing bullous lesions.

METHODS

This was cross sectional validation study conducted in a tertiary care hospital, over a period of 18 months. All the clinically diagnosed cases of bullous diseases were included and examined as histological sections by three histopathologists.

RESULTS

Out of 58 total cases, the most frequently diagnosed lesions included Pemphigus vulgaris (27%), Bullous pemphigoid (13.8%) and Pemphigus foliaceous (12.1%). Females comprised 55% of cases, age distribution was wide but most patient were in age bracket of 20-39 years.

CONCLUSION

There was 89.6% correlation between clinical and histopathological diagnosis. Only 2 cases were sent for Immunofluorescence studies, as histopathology was inconclusive in those cases. Therefore, we conclude that histopathological examination along with clinical correlation is a very useful way of diagnosing vesiculobullous disorders.

Role of ADAM10 and ADAM17 in the Regulation of Keratinocyte Adhesion in Pemphigus Vulgaris

The severe autoimmune blistering disease Pemphigus vulgaris (PV) is mainly caused by autoantibodies (IgG) against desmoglein (Dsg) 3 and Dsg1. The mechanisms leading to the development of blisters are not fully understood, but intracellular signaling seems to play an important role. Sheddases ADAM10 and ADAM17 are involved in the turnover of the desmosomal cadherin Dsg2 and ADAM10 has been shown to contribute to acantholysis in a murine pemphigus model. In the present study, we further examined the role of ADAM10 and ADAM17 both in keratinocyte adhesion and in the pathogenesis of PV. First, we found that inhibition of ADAM10 enhanced adhesion of primary human keratinocytes but not of immortalized keratinocytes. In dissociation assays, inhibition of ADAM10 shifted keratinocyte adhesion towards a hyperadhesive state. However, ADAM inhibition did neither modulate protein levels of Dsg1 and Dsg3 nor activation of EGFR at Y1068 and Y845. In primary human keratinocytes, inhibition of ADAM10, but not ADAM17, reduced loss of cell adhesion and fragmentation of Dsg1 and Dsg3 immunostaining in response to a PV1-IgG from a mucocutaneous PV patient. Similarly, inhibition of ADAM10 in dissociation assay decreased fragmentation of primary keratinocytes induced by a monoclonal antibody against Dsg3 and by PV-IgG from two other patients both suffering from mucosal PV. However, such protective effect was not observed in both cultured cells and ex vivo disease models, when another mucocutaneous PV4-IgG containing more Dsg1 autoantibodies was used. Taken together, ADAM10 modulates both hyperadhesion and PV-IgG-induced loss of cell adhesion dependent on the autoantibody profile.

In Vitro, Ex Vivo, and In Vivo Models for the Study of Pemphigus

Pemphigus is a life-threatening autoimmune disease. Several phenotypic variants are part of this family of bullous disorders. The disease is mainly mediated by pathogenic autoantibodies, but is also directed against two desmosomal adhesion proteins, desmoglein 1 (DSG1) and 3 (DSG3), which are expressed in the skin and mucosae. By binding to their antigens, autoantibodies induce the separation of keratinocytes, in a process known as acantholysis. The two main Pemphigus variants are Pemphigus vulgaris and foliaceus. Several models of Pemphigus have been described: in vitro, ex vivo and in vivo, passive or active mouse models. Although no model is ideal, different models display specific characteristics that are useful for testing different hypotheses regarding the initiation of Pemphigus, or to evaluate the efficacy of experimental therapies. Different disease models also allow us to evaluate the pathogenicity of specific Pemphigus autoantibodies, or to investigate the role of previously not described autoantigens. The aim of this review is to provide an overview of Pemphigus disease models, with the main focus being on active models and their potential to reproduce different disease subgroups, based on the involvement of different autoantigens.

Relapse of pemphigus foliaceus initiating at the site of irradiation in an elderly male with laryngeal carcinoma: Illustrating the concept of immunocompromised cutaneous district

Radiotherapy-induced or -aggravated pemphigus is not a common occurrence with only a few cases reported so far. The radiation disrupts the local immune regulation and alters the antigenicity of keratinocytes, but the exact etiology is not clear. We report a case of an elderly man operated for laryngeal carcinoma who presented with recurrence of pemphigus foliaceus lesions starting at the irradiation site. The appearance of vesiculobullous lesions at the site of irradiation should be evaluated thoroughly to rule out immunobullous diseases.

Antibody-Negative Paraneoplastic Autoimmune Multiorgan Syndrome (PAMS) in a Patient with Follicular Lymphoma Accompanied by an Excess of Peripheral Blood CD8+ Lymphocytes

Paraneoplastic autoimmune multiorgan syndrome (PAMS) is a life-threatening autoimmune disease associated with malignancies. Here, we present a patient initially misdiagnosed with “chronic” Stevens–Johnson syndrome. Over a year later, the patient was diagnosed with stage IV follicular lymphoma and treated with an anti-CD20 antibody. At this time, his skin condition had significantly worsened, with erythroderma and massive mucosal involvement, including in the mouth, nose, eyes, and genital region. Histopathology revealed lichenoid infiltrates with interface dermatitis, dyskeratoses, necrotic keratinocytes, and a dense CD8+ infiltrate with strong epidermotropism. Direct and indirect immunofluorescence tests for autoantibodies were negative. Remarkably, we retrospectively discovered a chronic increase in peripheral CD8+ lymphocytes, persisting for over a year. Consequently, the patient was diagnosed with antibody-negative PAMS. Three weeks later, he succumbed to respiratory failure. This dramatic case highlights the challenges in diagnosing PAMS, particularly in cases where immunofluorescence assays are negative. Importantly, we observed, for the first time, a chronic excess of CD8+ peripheral blood lymphocytes, associated with PAMS, consistent with the systemic, autoreactive T-cell-driven processes that characterize this condition.

Chronic exposure to the anti-m3 muscarinic acetylcholine receptor autoantibody in pemphigus vulgaris contributes to disease pathophysiology

Pemphigus vulgaris (PV) is a potentially lethal autoimmune mucocutaneous blistering disease characterized by binding of IgG autoantibodies (AuAbs) to keratinocytes (KCs). In addition to AuAbs against adhesion molecules desmogleins 1 and 3, PV patients also produce an AuAb against the M3 muscarinic acetylcholine (ACh) receptor (M3AR) that plays an important role in regulation of vital functions of KCs upon binding endogenous ACh. This anti-M3AR AuAb is pathogenic because its adsorption eliminates the acantholytic activity of PV IgG; however, the molecular mechanism of its action is unclear. In the present study, we sought to elucidate the mode of immunopharmacologic action of the anti-M3AR AuAb in PV. Short-term exposures of cultured KCs to PV IgG or the muscarinic agonist muscarine both induced changes in the expression of keratins 5 and 10, consistent with the inhibition of proliferation and upregulated differentiation and in keeping with the biological function of M3AR. In contrast, long-term incubations induced a keratin expression pattern consistent with upregulated proliferation and decreased differentiation, in keeping with the hyperproliferative state of KCs in PV. This change could result from desensitization of the M3AR, representing the net antagonist-like effect of the AuAb. Therefore, chronic exposure of KCs to the anti-M3AR AuAb interrupts the physiological regulation of KCs by endogenous ACh, contributing to the onset of acantholysis. Since cholinergic agents have already demonstrated antiacantholytic activity in a mouse model of PV and in PV patients, our results have translational significance and can guide future development of therapies for PV patients employing cholinergic drugs.

Punctate Pattern and Pemphigus: Is There Any Evidence of Punctate Pattern Among Iranian Patients?

AIM

To examine the prevalence of this novel pattern among Iranian patients with pemphigus and peruse the relationship between the presence of a punctate pattern with clinical severity of disease and histopathological findings.

METHODS

One hundred recently diagnosed patients with pemphigus were enrolled. DIF evaluation and routine light microscopy were performed on their biopsy specimens. Disease severity was determined using the Pemphigus Disease Area Index. Serum samples were collected to measure autoantibody titers using enzyme-linked immunosorbent assay.

RESULTS

All the samples evaluated by DIF showed a continuous linear pattern of intercellular IgG deposition, whereas none of them had a punctate pattern. Despite a significant correlation between the Pemphigus Disease Area Index score and autoantibody values, no association between histopathological findings and disease severity has been found.

CONCLUSION

We could not detect any punctate pattern among Iranian patients with pemphigus. The importance of this pattern in the diagnosis of pemphigus might be different among patients with different ethnic and genetic factors.

[Pemphigus vulgaris with exclusive affectation in the esophagus: a case report]

Background

Pemphigus vulgaris comprises a group of heterogeneous blistering autoimmune diseases of the skin and mucosa. Esophageal involvement within pemphigus vulgaris is rare with an uncertain prevalence that requires a detailed diagnostic and a therapeutic approach.

Clinical case

37-year-old female, with a history of treatment with Cox-2 inhibitors due to herniated disc. She is sent to the Gastroenterology Service for weight loss of approximately 5 kilos in a month, with the presence of dysphagia, odynophagia and retrosternal pain with poor tolerance to the oral route. Endoscopy was performed, which reported esophagitis dissecans superficialis (EDS), erythematous gastropathy of the antrum and normal duodenum. Findings were correlated with the diagnosis of pemphigus vulgaris with exclusive involvement of the esophagus. The evaluation did not identify lesions on the skin, oral cavity or other mucous membranes. A new endoscopy was performed as a control and it was found immunofluorescence of the esophageal biopsy reactive to IgG 2. Initial management was given with glucocorticoids, anti-inflammatories and immunosuppressants.

Conclusions

The importance of the study of pemphigus lies not only in the high associated morbidity and mortality, but also in its intrinsic rarity and the complexity of its detection, given that patients usually take several months to have an accurate diagnosis and even more time to achieve therapeutic goals. It is a priority the dissemination of the study of pemphigus among health professionals involved in its detection.

Desmogleins 1, 3, and E-cadherin immunohistochemical expression within mucocutaneous pemphigus vulgaris

Introduction

pemphigus vulgaris (PV) is an autoimmune condition characterized by the loss of adhesion between the epithelial cells and blister formation. The production of autoantibodies against desmosomal proteins, namely, desmoglein (DSG) 1 and DSG3, is considered a main event of PV. A full understanding of the role of adhesion molecules in the pathogenesis of PV is not fully elucidated yet. This study aimed to evaluate and correlate the immunohistochemical expression of E-cadherin (E-cad), DSG1, and DSG3 proteins in oral and skin PV.

Methods

this study was a retrospective analysis study. Positive PV cases were stained with anti-E-cad, anti-DSG1, and anti-DSG3 antibodies. The expression of each marker was determined by two pathologists according to an established scoring system: (E-cad: negative, weak, moderate, and strong), (DSG1: negative, weak, and strong), and (DSG3: negative and positive). The Chi-square and Pearson´s correlation tests were used to statistically analyze the data.

Results

forty-three biopsies (26 skin and 17 oral tissue samples) from 22 males and 21 female PV patients were included. The median age was 40.50 years. In total, the immunohistochemical expression was negative for DSG3, E-cad, and DSG1 in 81.4%, 18.5%, and 16.4%, respectively. DSG1 expression was significantly higher in males than females. A statistically significant correlation was found between E-cad and DSG3 expressions.

Conclusion

a significant difference in the expression of markers of both oral and skin PV was absent. Downregulation of DSG3 expression was the hallmark feature that also showed a positive correlation with E-cad expression.

RETROSPECTIVE CHART ANALYSIS OF PATIENTS DIGNOSED WITH ACANTHOLYTIC PEMPHIGUS FOR THE PERIOD 2008-2018

OBJECTIVE

The aim: Determine the clinical and anamnestic criteria that cause the аcantholytic pemphigus (AP) morbidity in the course of the treatment.

PATIENTS AND METHODS

Materials and methods: Analysis of medical histories of patients who underwent the therapy on the basis of the clinic for 10 years. In the analysis of 174 medical case histories were determined the factors provoking the onset and exacerbation of the disease. The disease severity was assessed using the IKEDA index.

RESULTS

Results: During the analysis, patients were divided into two groups. The I group - patients who required combination therapy - systemic glucocorticosteroids (SGCs) and immunosuppressant (azathioprine (AZA)). For patients of group II used SGCs - according to the indications. The presence of intoxication and signs of pyoderma were more common in patients of group I. The number of exacerbations per year for an unknown reason in group I was almost 3 times higher. The ineffectiveness of high starting doses of SGCs was 20.2% of cases compared with those in group II.

CONCLUSION

Conclusions: According to clinical and anamnestic data, during the retrospective analysis of case histories, the criteria determining the severity of acantholytic pemphigus during treatment were determined: the age of patients, the diagnosis period, the prevalence of lesions and severity of dermatosis according to the IKEDA index, the selection of adequate treatment tactics, taking into the complications caused as a result of the systemic glucocorticosteroids therapy.

[The study of microbiota in patients with bullous lesions of the oral mucosa]

THE AIM OF THE STUDY

The study by the method of tissue polymerase chain reaction of the species composition of the microbiota of lesions of the oral mucosa in patients with bullous lesions.

MATERIAL AND METHODS

Biopsy specimens of the oral mucosa of 51 patients were studied by the polymerase chain reaction method, of which 14 patients with pemphigus vulgaris, 17 patients with pemphigoid bullosa, and 20 patients with the bullous form of ruber lichen planus. 4 types of microorganisms have been identified - Fusobacterium, Streptococcus pneumoniae, Candida albicans, Ureaplasma spp. and viruses - Human Papillomavirus 16, Epstein-Barr virus and Citomegalovirus.

RESULTS

In the study of the microbiota of bullous lesions, associations of microorganisms and viruses were established in a significant number of cases. Associations of Str.pneumoniae and C. albicans were quite common in patients with pemphigus vulgaris in 26.3%, pemphigoid bullosa in 20.0%, and in patients with the bullous form of ruber lichen planus in 14.3% of cases. In patients with pemphigus vulgaris, the association of Str.pneumoniae, C. albicans and EBV was noted in 31.6% of cases. In patients with the bullous form of ruber lichen planus in a high percentage of cases (28.6%), the associations of Str. pneumoniae, EBV and CMV.

CONCLUSION

Identification at earlier stages of management of patients with bullous lesions Str. pneumoniae, Candida albicans, and Fusobacterium associated with herpes viruses should be regarded as one of the triggering mechanisms of an autoimmune conflict, which subsequently causes a specific clinical picture of these diseases.

[Diagnostically difficult case of pemphigus vulgaris isolated manifestation in the oral cavity]

A clinical example of the manifestation of vulgar pemphigus on the oral mucosa in the form of a single mildly painful erosion at the border of the soft and hard palate with extensive erosive lesions that existed in the patient for a long time is presented. The detection of a false positive reaction to syphilis led to an increase in the time of diagnosis. Only the appointment of a repeated full examination of the patient in accordance with clinical standards (cytological analysis, histological examination and indirect immunofluorescence method) allowed to establish the correct diagnosis, prescribe adequate therapy to the patient in a hospital setting and get a positive result.

Immunohistochemical Expression of Galectin-3 in Pemphigus Vulgaris

ABSTRACT

Pemphigus vulgaris (PV) is an autoimmune bullous disorder related to immunoglobulin-G autoantibodies against desmoglein-3. Galectin-3 is one of the main elements of the immunoglobulin-E group which is essential in the cell-cell or cell-matrix adhesion. Although the presence of immunoglobulin-E autoantibodies in PV has been observed, no studies have been performed to describe the role of galectin-3 in PV. We evaluated galectin-3 expression in PV as a first step in assessing its impact in the pathogenesis of this autoimmune blistering process. In a retrospective study, 56 specimens from 45 patients diagnosed with PV were stained with antibodies to galectin-3. The percentages of nuclear and cytoplasmic galectin-3 expression as well as staining intensity were evaluated around blisters and adjacent unaffected skin. We observed a significant decrease in galectin-3 cytoplasmic and nuclear expression as well as stain intensity around blisters compared with adjacent unaffected skin. Although autoantibodies against desmogleins trigger the blister formation in PV patients, loss of galectin-3 may play a role in the extension of blister formation by initiating cell-cell disassembly at the level of the intercellular keratinocyte desmosome. We demonstrated a lower expression of galectin-3 around the blisters in PV. The pathogenesis of the blister formation may be related to lower expression of galectin-3. Additional studies are necessary to clarify the result of this outcome and determine the accurate pathogenesis of blister formation in PV.

Histopathology of Pemphigus Vulgaris Revisited

ABSTRACT

Pemphigus vulgaris (PV) is a severe, potentially life-threatening autoimmune blistering disease, which is common in India. Although there is abundant literature on clinical and immunologic features, comprehensive studies on its histopathology are lacking. The aim of this study was to describe the histopathologic and immunofluorescence features as well as discuss various diagnostic pitfalls of PV. Histopathologic and immunofluorescence (DIF/IIF) findings were reviewed for 169 biopsies from 2007 to 2017 (11 years). The 169 samples included 152 skin, 16 oral mucosal, and 1 corneal biopsy. Maximum prevalence was noted in the fifth decade (57%) with a slight male preponderance. Vesicles were seen in 149 cases (88%), the level of which was suprabasal in 91(61%) and both suprabasal and intraepidermal in 50 cases (33.5%). Acantholytic cells were present in 142 cases (95%). Acantholytic keratinocytes showed rounded and polygonal acantholysis. 86 (51%) cases showed evidence of regeneration. Adnexal involvement was seen in 92 cases, commonest in the hair follicles. Unusual histologic findings included: intraepidermal bulla, absence of dermal inflammation, free floating hair shafts, multinucleated epithelial cells, eosinophil predominance; all of which are discussed. DIF was performed in 166 cases, of which 163 were positive (98%), and IgG was the commonest immunoreactant (96%). IIF was performed in 11 cases, of which 9 cases were positive for Dsg3. Although the diagnosis of PV rests on combined clinical, histologic, and IF features, histopathology as the sole means is also a powerful tool. It is important to be aware of the diagnostic pitfalls to optimize its utility.

Castleman disease and paraneoplastic pemphigus in a pregnant woman: A case report

RATIONALE

Orogenital ulcers can be observed in various conditions, such as Behcet disease, infection and also paraneoplastic pemphigus (PNP). Castleman disease (CD), which is a rare cause of paraneoplastic pemphigus represents a heterogenous lymphoproliferative disorder of unknown etiology. Paraneoplastic pemphigus associated with CD in pregnancy is rare and has not been reported yet.

PATIENT CONCERNS

We report a rare case of CD in a 26-year-old pregnant woman with orogenital ulcers. The patient suffered from mucosal erosions and uveitis at 23 weeks of gestation. A retroperitoneal mass (9.7×7.3×11.8 cm) was identified by CT scan.

DIAGNOSES

According to histological and immunohistological findings, a diagnosis of unicentric CD, hyaline vascular type, and PNP was formulated.

INTERVENTION

High dose methylpredisonlone was given for the therapy. Pancreatic uncinatectomy, portal vein and superior mesenteric vein repair, pancreaticojejunostomy, and caesarean section were performed on the patient to remove the tumor and the fetus.

OUTCOMES

The fetus did not survive after surgery. The patient did not achieve remission and she died from epidermolysis and sepsis several months later.

LESSONS

PNP associated with CD is a rare lymphoproliferative disorder and needs to be differentiated from other orogenital diseases by histological features.

ETHICS AND DISSEMINATION

Written informed consent was obtained from the patient for publication of this case report and accompanying images. Ethical approval of this study was granted by the Ethics Committee of West China Hospital of Sichuan University. (Ethics Reference No: 2021143).

Deep pemphigus (pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus) in dogs, cats and horses: a comprehensive review

Pemphigus is the term used to describe a group of rare mucocutaneous autoimmune bullous diseases characterized by flaccid blisters and erosions of the mucous membranes and/or skin. When the autoantibodies target desmosomes in the deep layers of the epidermis, deep pemphigus variants such as pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus develop. In this article, we will review the signalment, clinical signs, histopathology and treatment outcome of pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. Canine, feline and equine pemphigus vulgaris, pemphigus vegetans and paraneoplastic pemphigus have many features similar to the human counterpart. These chronic and often relapsing autoimmune dermatoses require aggressive immunosuppressive therapy. In animals, the partial-to-complete remission of pemphigus vulgaris and pemphigus vegetans has been achieved with high dose glucocorticoid therapy, with or without adjunct immunosuppressants; the prognosis is grave for paraneoplastic pemphigus.

Hallopeau type of pemphigus vegetans, an unusual clinical presentation of an infrequent disease

Pemphigus vegetans is a rare variant of pemphigus vulgaris, characterized by vegetative lesions that develop mainly in flexural areas. Herein, we present a middle-aged woman who presented to the emergency department with a rare cutaneous finding of bilateral axillary pustules that progressed over months to vegetant and malodorous plaques associated with subsequent painful erosions.

Pemphigus foliaceus in a patient with gastrointestinal stromal tumor treated with adjuvant imatinib mesylate

Pemphigus is an autoimmune bullous disease with a number of described associations, including medications, which have been grouped into three structural categories - thiol drugs, phenol drugs, and drugs with neither functional group [1]. Discontinuation of the offending medication is considered a mainstay of therapy. We report a patient in whom the onset of pemphigus foliaceus was associated with initiation of imatinib mesylate adjuvant therapy in a patient with resected gastrointestinal stromal tumor (GIST). Imatinib was continued because of the survival benefit to the patient with a resected, high risk GIST. Treatment with rituximab resulted in near resolution of his blistering rash and follow up enzyme-linked immunosorbent assay (ELISA) demonstrated reference range immunoreactivity for both desmoglein 1 and desmoglein 3. After dose increase of imatinib therapy owing to tumor growth, the patient subsequently again developed a similar eruption. Re-biopsy and ELISA were consistent with recurrence of pemphigus. In conclusion, although the patient's pemphigus was cleared with a single cycle of rituximab infusions while continuing imatinib therapy, the disease returned after imatinib dose was increased a year later, suggesting a dose-response relationship.

A Comparative Analysis of CD32A and CD16A Polymorphisms in Relation to Autoimmune Responses in Pemphigus Diseases and Subepithelial Autoimmune Blistering Disorders

Autoimmune blistering dermatoses (ABDs) are characterized by autoantibodies to keratinocyte surface antigens and molecules within the dermal–epidermal junction causing disruption of skin integrity. The affinity of Fc receptors (FcRs) causing an autoimmune response in ABDs may vary based on single-nucleotide polymorphisms (SNPs) in FcRs determining the course of disease. This study aimed to explore the effects of CD16A and CD32A SNPs on the autoimmune response in several ABDs. In total, 61 ABDs patients were investigated. ELISA tests, direct immunofluorescence (DIF), TaqMan SNP Genotyping Assays, and statistical analyses were performed. The CA genotype (composed of allele C and A) of rs396991 in CD16A had a higher affinity for tissue-bound IgG1 in pemphigus and for C3 in subepithelial ABDs, showing statistical significance. The greatest relative risk (odds ratio) was reported for AA (rs396991 of CD16A) and CC (rs1801274 of CD32A) homozygotes. There were no statistically significant differences between certain genotypes and specific circulating autoantibodies (anti-DSG1, anti-DSG3 IgG in pemphigus; anti-BP180, anti-BP230 IgG) in subepithelial ABDs. Our findings indicated that rs396991 in CD16A may be of greater importance in ABDs development. Moreover, FcR polymorphisms appeared to have a greater impact on tissue-bound antibodies detected using DIF than circulating serum antibodies in ABDs.

Paraneoplastic Dermatoses: A Brief General Review and an Extensive Analysis of Paraneoplastic Pemphigus and Paraneoplastic Dermatomyositis

Skin manifestations of systemic disease and malignancy are extremely polymorphous. Clinicians should be familiarized with paraneoplastic dermatoses in order to perform an early diagnosis of the underlying neoplasm. Lack of familiarity with cutaneous clues of internal malignancy may delay diagnosis and treatment of cancer. In this review, we described several paraneoplastic dermatoses and discussed extensively two paradigmatic ones, namely paraneoplastic pemphigus and paraneoplastic dermatomyositis.

Red Blood Cell Distribution Width Is Increased in Patients with Pemphigus: A Case-Control Study

BACKGROUND

Red blood cell distribution width (RDW) has recently emerged as an inflammatory marker in several inflammatory diseases but has not been investigated in patients with pemphigus.

OBJECTIVE

We aimed to examine RDW percentage in patients with pemphigus relative to control subjects and to assess the association between this biomarker and the morphological characteristics of the disease.

METHODS

This case-control study included 183 pemphigus patients and 915 age- and sex-matched control subjects. RDW, hemoglobin, and mean corpuscular volume (MCV) were measured for all study participants.

RESULTS

The RDW was significantly higher in patients with pemphigus than in controls (13.7±1.3 vs. 13.4±1.1%, respectively; P=0.001). A significant association between RDW and pemphigus was demonstrated in multivariate analysis (odds ratio, 1.22; 95% confidence interval, 1.01-1.46; P=0.036). The RDW was higher in patients with pemphigus vulgaris (PV) than in pemphigus foliaceus (PF; P=0.043), and in those with mucocutaneous PV relative to those with mucosal only and cutaneous only PV. The RDW increased significantly following treatment (P<0.001).

CONCLUSION

Pemphigus patients demonstrated elevated RDW as compared with healthy controls. RDW may be a feasible biomarker in patients with pemphigus. Although it clearly does not replace any of the accepted diagnostic immunopathological criteria, increased RDW may be more suggestive of PV than PF, and of mucocutaneous rather than cutaneous PV. The remarkable increase following treatment may be ascribed to the corticosteroid-induced erythropoiesis.