Paraneoplastic pemphigus: Revised diagnostic criteria based on literature analysis

Autoimmune pemphigus: difficulties in diagnosis and the molecular mechanisms underlying the disease

Recently recognised as a desmosomal disorder, autoimmune pemphigus remains severe in some of its forms, such as pemphigus vulgaris. This review is divided into four parts. "Cellular and molecular mechanisms in autoimmune pemphigus" discusses in detail antigenic targets, antibodies, immunological and genetic mechanisms of apoptosis and the involvement of cells and organelles (keratinocytes, lymphocytes, eosinophils and neutrophils) in different forms of pemphigus. These advances have led to today's first-line biologic therapy for pemphigus. The section "Specific features in the diagnosis of immune pemphigus" deals with the clinical diagnostic clues (enanthema, intertrigo, pruritus, distribution of lesions). The third section, "Characteristics and challenges in different types of pemphigus", focuses on the importance of using standardised diagnostic criteria in paraneoplastic pemphigus and pemphigus herpetiformis, the specific and difficult situations of differentiation between bullous lupus and autoimmune Senear-Usher pemphigus, between IgA forms of pemphigus or differentiation with other autoimmune diseases or neutrophilic dermatoses. The possibility of subtype cross-reactivity in pemphigus is also discussed, as is the diagnosis and course of the disease in pregnant women. The final section is an update of the "gold standard for the diagnosis and evaluation of autoimmune pemphigus", the role and place of direct immunofluorescence and additional serological tests. This revision is the first to combine the difficulties in clinical diagnosis with new molecular insights. It provides a comprehensive overview of recent advances in the understanding of autoimmune pemphigus, bridging the clinical challenges and complexities of diagnosing different forms of pemphigus, and is a valuable resource for clinicians caring for patients with pemphigus.

Complete Resolution of Atypical Paraneoplastic Pemphigus Following Treatment With Dupilumab

Paraneoplastic pemphigus (PNP) is a rare autoimmune mucocutaneous blistering condition associated with underlying malignancies. While severe stomatitis is usually a hallmark feature of PNP, it may present with the absence of oral manifestations. Proposed diagnostic criteria include the presence of mucosal lesions with or without cutaneous involvement, concomitant internal neoplasm, anti-plakin autoantibodies, histopathology with acantholysis and/or lichenoid interface changes, and direct immunofluorescence (DIF) with intercellular and/or basement membrane deposition of immunoglobulin G (IgG) or complement component-3 (C3). Management of PNP traditionally involves immunosuppressants; however, prognosis remains poor. This report presents a 77-year-old male patient with an ongoing, intensely painful, and pruritic rash with diffuse scaling, erythema, crust, bullae, and erosions covering 90% body surface area that notably lacked mucosal involvement. Biopsies revealed acantholysis with mixed infiltrate lichenoid interface dermatitis and DIF with 3+ intercellular and basement membrane deposition of C3 and IgG. Additional workup revealed elevated desmoglein-1 and bullous pemphigoid antigen-1 (BPAG1/BP230) autoantibodies and intramucosal gastrointestinal adenocarcinoma, satisfying the diagnostic criteria for PNP. Due to his history of type 2 diabetes mellitus, chronic non-healing ulcers, and untreated malignancy, he was a poor candidate for first-line immunosuppressants. Additionally, the patient experienced significant pruritus resistant to topical corticosteroids and oral antihistamines. For these reasons, dupilumab was elected to control the patient's pruritus. After two months, there was significant improvement in skin lesions, and after four months, there were complete resolution of pruritus and 100% clearance of skin lesions. This report highlights a unique and previously unreported case of complete resolution of atypical PNP following empiric treatment with dupilumab, a monoclonal antibody against interleukin 4/13 receptor-α.

Oral Paraneoplastic Pemphigus: A Scoping Review on Pathogenetic Mechanisms and Histo-Serological Profile

Paraneoplastic pemphigus (PNP) is a rare autoimmune disorder associated with underlying neoplasms, predominantly Non-Hodgkin Lymphomas, affecting adults aged 45 to 70. This review analyzed 87 articles from MEDLINE/PubMed, Ovid and Scopus focusing on patients with oral manifestations of PNP, emphasizing histological and serological aspects and discussing recent updates on pathogenetic options. Key findings revealed that PNP is often diagnosed before the neoplasm, with Follicular variant Non-Hodgkin Lymphoma and Castleman Disease being the most common associations. Histopathological analysis showed suprabasal acantholysis and inflammation, and serological tests identify a comprehensive autoantibody panel, underscoring the need for standardized diagnostic criteria and improved serological testing.

Lichenoid paraneoplastic pemphigus in a patient presenting with follicular lymphoma: a review of the literature

Paraneoplastic pemphigus (PNP) is a rare, autoimmune, mucocutaneous blistering disease that is almost always associated with a confirmed or occult neoplasm. PNP often presents with characteristic features of intractable stomatitis and polymorphous cutaneous eruptions, including blisters and lichenoid dermatitis caused by humoral and cell-mediated autoimmune reactions. We present the following case of a patient with follicular lymphoma (FL) who developed lichenoid PNP involving the buccal mucosa and lateral tongue. We also summarize the literature, discussing current proposed mechanisms, guidelines, and treatment of this unique disease. While patients can achieve complete remission from their underlying neoplasm, most patients with PNP do not have a good survival time with a 5-year survival rate of only 38%. This case sheds light on an uncommon occurrence, highlights the need for further studies around PNP as it relates to FL, and suggests that T cell immunosuppressive therapy may be effective in treating FL patients with PNP.

Uncommon and Unusual Variants of Autoimmune Bullous Diseases

Background

Autoimmune blistering diseases (AIBDs) are a type of dermatosis with antibodies produced against various structural proteins of the epidermis or dermoepidermal junction. AIBDs are broadly divided into intraepidermal and subepidermal types. Apart from the common AIBDs, there is an array of uncommon AIBDs.

Objective

To discuss uncommon variants of AIBDs so that the readers are updated about them.

Methods

In this review, we have discussed uncommon and unusual variants like pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus, induced pemphigus, IgG/IgA pemphigus, oral lichenoid pigmentation in pemphigus, pemphigus acanthoma, and follicular pemphigus. Rarer variants of the pemphigoid group of disorders include anti-laminin 332 pemphigoid, mixed linear IgA/IgG pemphigoid, anti-p200 pemphigoid, Brunsting-Perry pemphigoid, IgM pemphigoid, granular C3 pemphigoid, anti-p105 pemphigoid, ORF-induced anti-laminin 332 pemphigoid, and acral purpura in dermatitis herpetiformis.

Conclusion

This review will help in early diagnosis and treatment of uncommon and unusual variants of AIBDs.

Direct immunofluorescence demystified: Essential insights and recent advances for dermatologists

Direct immunofluorescence (DIF) is widely used in dermatopathology for the diagnosis of autoimmune blistering diseases (AIBDs), cutaneous vasculitis, and connective tissue disorders. Although it is easy and useful to perform, it needs technical expertise and experience for proper interpretation. The yield of DIF depends on multiple factors including the adequacy, transportation, storage, processing, and interpretation of the biopsy specimen. Effective collaboration between the dermatologist and dermatopathologist along with meticulous clinico-pathological correlation is crucial for accurately interpreting DIF in the appropriate clinical context. In this narrative review of DIF in dermatology, we discuss the indications of DIF, recent updates on the selection of optimum biopsy sites, basic techniques of DIF including the classical transport medium and its alternatives, processing and staining technique, patterns in various diseases, advancements such as serration pattern analysis, and latest recommendations on the use of DIF in cutaneous disorders.

Paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome: Part II. Diagnosis and management

In the second part of this Continuing Medical Education article on paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome (PNP/PAMS), its diagnostic criteria, investigative work-up, and management are reviewed. PNP/PAMS is a rare autoimmune blistering disorder associated with high morbidity and mortality. Recognizing PNP/PAMS's key features and its diagnostic criteria is critical in initiating appropriate work-up. Evaluating PNP/PAMS requires knowledge of its findings on histopathology, direct immunofluorescence, indirect immunofluorescence, and enzyme-linked immunosorbent assay. Lastly, treatments for PNP/PAMS are reviewed with suggestions based on case reports and expert opinions in the literature.

Paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome: Part I. Clinical overview and pathophysiology

Paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome (PNP/PAMS) is a highly fatal autoimmune blistering disease. The condition occurs in patients with underlying benign or malignant neoplasms, most commonly lymphoproliferative disorders. Both humoral and cell-mediated immunities contribute to the pathogenesis, and autoantibodies against plakin family proteins are characteristic. Patients typically present with severe stomatitis and polymorphous skin lesions, which are often resistant to treatment. Bronchiolitis obliterans (BO) is a frequent complication which contributes to the high mortality rate of PNP/PAMS. Given the rarity of this disorder and heterogeneity of clinical presentation, clinicians should maintain a high index of suspicion for PNP/PAMS to avoid delayed diagnosis. In this first part of a two-part continuing medical education (CME) series, risk factors, pathogenesis, and clinical features of PNP/PAMS are discussed.

Paraneoplastic Dermatoses and Cutaneous Metastases

Paraneoplastic syndromes include a variety of cutaneous presentations that have an associated internal malignancy. Some syndromes have a strong correlation to specific internal malignancies, whereas others are associated with a multitude of tumors. There are many cutaneous manifestations that suggest hematologic disorders, which will be reviewed in detail. Cutaneous metastases are commonly from breast and lung cancers and can present as nodules, vascular lesions, eczematous dermatitis, or inflammatory lesions. The most common histologic presentation of cutaneous metastasis is that of a dermal-based or subcutaneous-based nodule with sparing of the epidermis. Determination of origin of tumor requires immunohistochemistry and clinical correlation.

Retrospective cohort evaluation of non-HIV Castleman disease from a single academic center in Beijing, China

The purpose is to ascertain the clinical impact of Castleman disease (CD) by reassessment of the real-world data from Peking University First Hospital (PKUFH). The results will contribute to the standardization of diagnosis and treatment on CDs. Based on the last 15-year retrospective real-world data from Peking University First Hospital (PKUFH), we reclassified and re-evaluated the clinical and pathological information of patients with pathologically suspected diagnosis of CD. A total of 203 patients were included in our study, in which the diagnosis of CD was confirmed in 189 cases, including 118 patients with unicentric CD (UCD, n = 118, 62.4%) and 71 patients with multicentric CD (MCD, n = 71, 37.6%). A total of 44.1% (n = 52) of UCDs in our cohort were complicated with paraneoplastic pemphigus (PNP). The treatment of UCD is primarily surgical, with a 5-year overall survival (OS) of 88.1%. Patients with PNP had a poorer prognosis than those without PNP (82.9% (95% CI 123-178) vs 92.8% (95% CI 168-196), log-rank p = 0.041). The rate of concurrent systemic symptoms was 74.6% (n = 53), and renal involvement occurred in 49.3% (n = 35) MCD patients. The MCD treatments were mainly chemotherapy regimens, with a 5-year OS of 77.6% (95% CI, 143-213). Patients with UCD demonstrate a better overall prognosis than patients with MCD. But the prognosis of those complicated with PNP was poor. The differential diagnosis of MCD is extensive. MCD treatment in China is heterogeneous. The inaccessibility of anti-IL-6-targeted drugs in China may contribute to the poor prognosis for patients with MCD.A preprint has previously been published (Guo et al. 34).

Indirect immunofluorescence on rat bladder epithelium in patients with pemphigus vulgaris with an extended follow-up

Background

Indirect immunofluorescence (IIF) on rat bladder epithelium (RBE) has been widely used to detect anti-plakin antibodies present in paraneoplastic pemphigus (PNP). However, anti-plakin antibodies have also been found in a group of patients with pemphigus vulgaris (PV).

Objectives

To assess the reactivity rate of PV sera in IIF using RBE as substrate and the diagnostic usefulness of the aforementioned test.

Methods

Patients diagnosed with PV presenting to Razi Hospital, Tehran, Iran, were recruited. The patients' demographics, disease severity, and response to the initial treatment were recorded. Sera were collected and tested by IIF on RBE and by desmoglein 3/1 (Dsg 3/1) enzyme-linked immunosorbent assay. Patients were followed up closely for a mean of 53.9 months for any evidence of malignancy.

Results

Forty-six patients were enroled (mean age of 42.9 years old, 31 females). Nine sera (19.6%) showed reactivity in IIF on RBE. Mean serum anti-Dsg levels did not differ significantly among the two groups with positive and negative IIF results. Negative anti-Dsg3 was related to a higher positive rate in IIF on RBE. There was no significant correlation between the reactivity of IIF on RBE and patients' demographic, clinical, or serological characteristics.

Conclusions

IIF on RBE is a sensitive test for detecting antibodies against plakins. However, it has a relatively high false-positive rate in PV, probably due to the epitope spreading phenomenon. This test should be suggested when there is a clinical or immunohistopathological suspicion of PNP and should be interpreted with caution.

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.

Bronchiolitis Obliterans With Anti-Epiplakin Antibodies in a Boy With Paraneoplastic Pemphigus

Paraneoplastic pemphigus is a rare and severe autoimmune blistering disease characterized by a recalcitrant and severe mucositis, and polymorphic cutaneous lesions, associated with benign and malignant neoplasms. Paraneoplastic pemphigus is caused by production of autoantibodies against various epidermal proteins involved in cell adhesion. Bronchiolitis obliterans (BO) is one of the leading causes of mortality in these patients. Recent advances have associated the presence of anti-epiplakin antibodies with the development of BO in adult patients. Here we describe the first pediatric patient in whom the association of anti-epiplakin antibodies and BO have been reported so far.

Vesiculobullous Diseases

A diverse range of inflammatory dermatoses are characterized by vesicles or bullae [...]

An Updated Review of Pemphigus Diseases

Clinicians may encounter a variety of skin conditions that present with vesiculobullous lesions in their everyday practice. Pemphigus vulgaris, pemphigus foliaceus, IgA pemphigus, and paraneoplastic pemphigus represent the spectrum of autoimmune bullous dermatoses of the pemphigus family. The pemphigus family of diseases is characterized by significant morbidity and mortality. Considering the risks associated with a delayed diagnosis or misdiagnosis and the potential for overlap in clinical features and treatment, evaluation for suspected pemphigus disease often requires thorough clinical assessment and laboratory testing. Diagnosis is focused on individual biopsies for histopathology and direct immunofluorescence. Additional laboratory methods used for diagnosis include indirect immunofluorescence and enzyme-linked immunosorbent assay. Recent advancements, including anti-CD20 therapy, have improved the efficacy and reduced the morbidity of pemphigus treatment. This contribution presents updates on the pathophysiology, clinical features, diagnostic work-up, and medical management of pemphigus. Improved strategies for diagnosis and clinical assessment are reviewed, and newer treatment options are discussed.

Pemphigus Herpetiformis-Type Drug Reaction Caused by Programmed Cell Death Protein-1 Inhibitor Treatment

Reports of immune-related adverse events caused by programmed cell death protein-1 inhibitor are becoming increasingly frequent. Herein, we report the first case of pemphigus herpetiformis-type drug reaction presented after the treatment of tislelizumab (6 cycles) in a primary non-small cell lung carcinoma patient. A 56-year-old Chinese man was referred to our department for pruritic annulare erythema and blister for two weeks. Histological finding revealed blister formation in the epidermis and eosinophilic infiltration in the blister fluid. Direct immunofluorescence showed intercellular deposition of IgG and C3 within the lower part of epidermis. Serum anti-intercellular antibodies were positive at 1:100 dilution. Based on history and clinicopathological correlation, herpetiformis-type drug-induced pemphigus was diagnosed, which was possibly be induced by tislelizumab. To the best to our knowledge, there is no report of pemphigus herpetiformis-type drug-induced reaction associated with programmed cell death protein-1 inhibitor treatment.