Prevalence of myasthenia gravis and associated autoantibodies in paraneoplastic pemphigus and their correlations with symptoms and prognosis

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.

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

BACKGROUND

Paraneoplastic pemphigus (PNP), also called paraneoplastic autoimmune multiorgan syndrome (PAMS), is a rare autoimmune disease with mucocutaneous and multi-organ involvement. PNP/PAMS is typically associated with lymphoproliferative or haematological malignancies, and less frequently with solid malignancies. The mortality rate of PNP/PAMS is elevated owing to the increased risk of severe infections and disease-associated complications, such as bronchiolitis obliterans.

OBJECTIVES

These guidelines summarize evidence-based and expert-based recommendations (S2k level) for the clinical characterization, diagnosis and management of PNP/PAMS. They have been initiated by the Task Force Autoimmune Blistering Diseases of the European Academy of Dermatology and Venereology with the contribution of physicians from all relevant disciplines. The degree of consent among all task force members was included.

RESULTS

Chronic severe mucositis and polymorphic skin lesions are clue clinical characteristics of PNP/PAMS. A complete assessment of the patient with suspected PNP/PAMS, requiring histopathological study and immunopathological investigations, including direct and indirect immunofluorescence, ELISA and, where available, immunoblotting/immunoprecipitation, is recommended to achieve a diagnosis of PNP/PAMS. Detection of anti-envoplakin antibodies and/or circulating antibodies binding to the rat bladder epithelium at indirect immunofluorescence is the most specific tool for the diagnosis of PNP/PAMS in a patient with compatible clinical and anamnestic features. Treatment of PNP/PAMS is highly challenging. Systemic steroids up to 1.5 mg/kg/day are recommended as first-line option. Rituximab is also recommended in patients with PNP/PAMS secondary to lymphoproliferative conditions but might also be considered in cases of PNP/PAMS associated with solid tumours. A multidisciplinary approach involving pneumologists, ophthalmologists and onco-haematologists is recommended for optimal management of the patients.

CONCLUSIONS

These are the first European guidelines for the diagnosis and management of PNP/PAMS. Diagnostic criteria and therapeutic recommendations will require further validation by prospective studies.

Paraneoplastic pemphigus uncovers distinct clinical and biological phenotypes of western unicentric Castleman disease

Unicentric Castleman disease (UCD) is a lymphoproliferative disease of unknown cause. Paraneoplastic pemphigus (PNP) is a major complication shown to be associated with a poor prognosis, with particular severity in patients with bronchiolitis obliterans (BO). This study describes the clinical and biological characteristics of UCD-PNP patients in a large Western cohort. A total of 148 patients diagnosed with UCD were identified, including 14 patients with a defined PNP. PNP was significantly associated with myasthenia gravis (MG) and FDC sarcoma during follow-up (FDCS). PNP was also significantly associated with reduced survival. These data, together with a multivariate analysis by principal components, led to the identification of UCD-PNP as a group at risk of MG, FDCS and death. PDGFRB sequencing performed on UCD lesions from six patients found the gain-of-function p.N666S variant in two. Interestingly, both patients had hyaline-vascular UCD subtype, were in the UCD-PNP subgroup and had FDCS. Sera from 25 UCD-PNP patients and 6 PNP patients without UCD were tested for PNP-associated autoantibodies. Sera from UCD-PNP patients had a strong reactivity against the N-terminal domain of recombinant periplakin (rPPL, 82%) and showed reactivity against at least two domains of rPPL. These features were not found in patients with UCD alone or in the PNP group without UCD. These data indicate that UCD-PNP patients belong to a subgroup sharing strong clinical and biological identity that might help to decipher the different dynamics of UCD natural history.

The Role of Non-Neuronal Acetylcholine in the Autoimmune Blistering Disease Pemphigus Vulgaris

The importance of acetylcholine (ACh) in keratinocyte adhesion and acantholysis has been investigated over the last three decades, particularly in the pathophysiology of autoimmune blistering dermatoses. Pemphigus vulgaris (PV) is an autoimmune blistering skin disease where autoantibody-mediated suprabasilar intraepidermal splitting causes flaccid blisters and non-healing erosions of the oral mucosa and sometimes also of the skin. Historically, acantholysis in PV was thought to be driven by anti-desmoglein (Dsg) antibodies. Herein, we describe the role of autoantibodies against keratinocyte muscarinic and nicotinic acetylcholine receptors, as well as the annexin-like molecule pemphaxin that also binds ACh, in the immunopathogenesis of PV. The identification of targets in this disease is important, as they may lead to novel diagnostic and therapeutic options in the future for this potentially deadly disease.

Paraneoplastic pemphigus associated with Castleman disease: A multicenter case series

INTRODUCTION

Paraneoplastic pemphigus (PNP) is a rare, often fatal, autoimmune blistering disease of the skin and mucous membranes. In children, PNP is frequently associated with Castleman disease (CD). This series describes five cases of PNP associated with CD.

METHODS

Data were collected retrospectively from the medical records of patients with a diagnosis of PNP and CD from January 2013 to June 2022. Patients ≤22 years old with clinical and immunopathologic evidence of PNP were included; CD was diagnosed histopathologically.

RESULTS

Two children, two adolescents, and one young adult (two males, three females) were included. The average age at disease presentation was 11.8 years (range: 7-22 years). Oral (n = 5) and anogenital (n = 3) mucositis were common. Four patients had "unicentric" CD (UCD); one patient had "multicentric" CD (MCD). Castleman tumors were in the retroperitoneum (n = 4) or axilla (n = 1). One patient had myasthenia gravis without thymoma. Three patients had bronchiolitis obliterans (BO). Three patients had complete resection of their CD; two had partial resection. Three patients remain alive with a median follow-up of 13 months (range: 12 months to 13 years); two are clinically stable with resolution of mucocutaneous lesions; one has persistent BO requiring ongoing ventilatory support. Patients who remain alive had UCD with complete resection; all deceased patients had partial resection and BO.

CONCLUSION

Most patients had UCD, and the retroperitoneum was the most common location. Patients with MCD, incomplete resection, and BO died; patients with UCD and complete resection remain alive, even in the setting of BO. Consideration of PNP is critical when pediatric patients present with mucositis as PNP may be clinically indistinguishable from more common causes of mucositis.

Investigation of comorbid autoimmune diseases in women with autoimmune bullous diseases: An interplay of autoimmunity and practical implications

Autoimmune bullous diseases are a group of skin disorders resulting from an autoimmune reaction against intercellular adhesion molecules or components of the basement membrane of skin and mucosa. Autoimmune disorders often occur in patients with a history of another autoimmune disease and most autoimmune diseases have a striking female predominance. In this review, we aim to analyze the different associations of autoimmune bullous diseases with other autoimmune diseases and highlight the distinctiveness of the female gender in these associations.

Myocardial Damage in a Highly Suspected Case With Paraneoplastic Pemphigus: A Case Report and Literature Review

Paraneoplastic pemphigus (PNP) is a rare mucocutaneous autoimmune disease. It has multiple clinical accompanied symptoms by affecting various types of epithelia, including the gastrointestinal and respiratory tract. However, an extensive review of the literature found no cases of PNP associated with myocardial damage. Here, we present a 56-year-old male patient with clinically and histopathologically typical paraneoplastic pemphigus (PNP), who had sustained myocardial injury due to non-cardiac disease involvement. Therefore, we suppose that, when persistent cardiac necrosis markers are elevated in patients with paraneoplastic pemphigus (PNP), the possibility of concomitant myocardial damage should get more attention from clinicians to obtain quick diagnosis and treatment.

Epidemiology of Pemphigus

Pemphigus is an epidemiologically heterogeneous group of autoimmune bullous diseases comprising pemphigus vulgaris (PV), pemphigus foliaceus, paraneoplastic pemphigus, IgA pemphigus, and pemphigus herpetiformis. Recently, our knowledge about the frequency of pemphigus, which is highly variable between different populations, has considerably expanded, and the first non-HLA genes associated with PV have been identified. In addition, a variety of comorbidities, including other autoimmune diseases, hematological malignancies, and psoriasis, have been described in this variant. Here, initial data about the impact of COVID-19 on this fragile patient population are discussed and perspectives for future epidemiological studies are outlined.

Paraneoplastic autoimmune multiorgan syndrome

Originally described by Anhalt as paraneoplastic pemphigus in 1990, paraneoplastic autoimmune multiorgan syndrome (PAMS) is a potentially lethal blistering disease, characterized by polymorphous clinical features, including mucocutaneous erosions, blisters, lichenoid papules, and erythemas. Several autoantibodies have been detected in serum of PAMS patients, including antiplakins, anti-alpha-2-macroglobulin like 1, and antidesmogleins autoantibodies. The mortality rate of PAMS is up to 90%. This is due on the one hand to the poor response to treatments and on the other hand to the delay in the diagnosis and to the prognosis of the underlying neoplasia.

Paraneoplastic Neurological Syndromes: Study of Prevalence in a Province of the Lombardy Region, Italy

Paraneoplastic neurological syndromes (PNSs) are a heterogeneous group of rare immune-mediated diseases associated with cancer. The aim of this study was to investigate the prevalence of PNSs in the province of Brescia. PNS prevalence was calculated using the Lombardy regional hospital admission records from 1998 to 2003. We used the website "Epidemiologic and Economic Atlas of Hospital Activities in Lombardy" and the "International Statistical Classification of Diseases and Related Health Problems". In the province of Brescia, we found 54 cases of PNSs, 29 with subacute neuropathies, five with paraneoplastic cerebellar degeneration and 20 with encephalomyelitis. Peripheral nervous system diseases were the most frequent neurological disorders. In Lombardy, the number of PNS patients admitted was 322 (133 with encephalomyelitis, 21 with paraneoplastic cerebellar degeneration, 166 with polyneuropathies and two with optic degeneration). In Lombardy, the prevalence of PNSs was 25 in 100,000 hospital admissions and 5.92 in 100,000 for the Lombardy population. Our results show a discrete presence of PNS patients in the province of Brescia and in the Lombardy region as a whole.

Predominant Stroma-Rich Feature in Hyaline Vascular Variant of Castleman Disease Is Associated With Paraneoplastic Pemphigus

OBJECTIVES

We aimed to describe the clinical and histopathologic features of Castleman disease (CD), particularly emphasizing its associations with paraneoplastic pemphigus (PNP) and prognosis.

METHODS

We retrospectively enrolled 123 CD patients at our center. Clinical, pathologic, and laboratory data were reviewed.

RESULTS

Fifty percent of the patients had PNP. Compared with those without PNP, patients with PNP-associated CD had more hyaline vascular (HV) variants (83.9% vs 57.4%), fewer mixed cellular variants (16.1% vs 24.6%), and no plasmacytic variants (0% vs 18.0%). Thirty-eight of 87 patients with the HV variant of CD (HV-CD) had stroma-rich (SR) features, and the incidence rate was higher in those with PNP-associated CD than in those without PNP (48.4% vs 13.1%, P < .001). The SR variant was associated with higher PNP-associated IgG titers than SR absence before surgery (median 1:160 vs 1:80, P = .019) or after surgery (median 1:160 vs 1:40, P = .013). The SR variant was also an unfavorable prognostic factor for CD survival in univariate analysis. The 3-year survival rates were 47.5% among those with PNP and 87.7% among those without PNP (P < .001).

CONCLUSIONS

PNP is associated with specific subtypes of CD and affects survival. The SR variant of HV-CD positively correlates with the incidence of PNP.

Modern diagnostic methods of paraneoplastic pemphigus

Paraneoplastic pemphigus (PNP) is one of the least investigated and rare forms of bullous dermatoses, which comes from underlying neoplasm. The article presents a literature review of dermatologist`s longstanding international experience about etiology, pathogenesis, diagnostics and treatment of this disease. According to the research results of native and foreign authors systematization of modern diagnostic methods of PNP and detectable antigens was performed.

Conflict of interest: the authors state that there is no potential conflict of interest requiring disclosure in this article.

Oral Lesions in Autoimmune Bullous Diseases: An Overview of Clinical Characteristics and Diagnostic Algorithm

Autoimmune bullous diseases are a group of chronic inflammatory disorders caused by autoantibodies targeted against structural proteins of the desmosomal and hemidesmosomal plaques in the skin and mucosa, leading to intra-epithelial or subepithelial blistering. The oral mucosa is frequently affected in these diseases, in particular, in mucous membrane pemphigoid, pemphigus vulgaris, and paraneoplastic pemphigus. The clinical symptoms are heterogeneous and may present with erythema, blisters, erosions, and ulcers localized anywhere on the oral mucosa, and lead to severe complaints for the patients including pain, dysphagia, and foetor. Therefore, a quick and proper diagnosis with adequate treatment is needed. Clinical presentations of autoimmune bullous diseases often overlap and diagnosis cannot be made based on clinical features alone. Immunodiagnostic tests are of great importance in differentiating between the different diseases. Direct immunofluorescence microscopy shows depositions of autoantibodies along the epithelial basement membrane zone in mucous membrane pemphigoid subtypes, or depositions on the epithelial cell surface in pemphigus variants. Additional immunoserological tests are useful to discriminate between the different subtypes of pemphigoid, and are essential to differentiate between pemphigus and paraneoplastic pemphigus. This review gives an overview of the clinical characteristics of oral lesions and the diagnostic procedures in autoimmune blistering diseases, and provides a diagnostic algorithm for daily practice.

Paraneoplastic pemphigus: a clinical, laboratorial, and therapeutic overview

Paraneoplastic pemphigus is a rare and severe autoimmune blistering disease characterized by mucocutaneous lesions associated with benign and malignant neoplasms. Diagnostic criteria include the presence of chronic mucositis and polymorphic cutaneous lesions with occult or confirmed neoplasia; histopathological analysis exhibiting intraepidermal acantholysis, necrotic keratinocytes, and vacuolar interface dermatitis; direct immunofluorescence with intercellular deposits (IgG and C3) and at the basement membrane zone (IgG); indirect immunofluorescence with intercellular deposition of IgG (substrates: monkey esophagus and simple, columnar, and transitional epithelium); and, autoreactivity to desmogleins 1 and 3, desmocollins 1, 2, and 3, desmoplakins I and II, envoplakin, periplakin, epiplakin, plectin, BP230, and α-2-macroglobulin-like protein 1. Neoplasias frequently related to paraneoplastic pemphigus include chronic lymphocytic leukemia, non-Hodgkin lymphoma, carcinomas, Castleman disease, thymoma, and others. Currently, there is no standardized treatment for paraneoplastic pemphigus. Systemic corticosteroids, azathioprine, mycophenolate mofetil, cyclosporine, rituximab, cyclophosphamide, plasmapheresis, and intravenous immunoglobulin have been used, with variable outcomes. Reported survival rates in 1, 2, and 5 years are 49%, 41%, and 38%, respectively.

Pemphigus

Pemphigus consists of a group of rare and severe autoimmune blistering diseases mediated by pathogenic autoantibodies mainly directed against two desmosomal adhesion proteins, desmoglein (Dsg)1 and Dsg3 (also known as DG1 and DG3), which are present in the skin and surface-close mucosae. The binding of autoantibodies to Dsg proteins induces a separation of neighbouring keratinocytes, in a process known as acantholysis. The two main pemphigus variants are pemphigus vulgaris, which often originates with painful oral erosions, and pemphigus foliaceus, which is characterised by exclusive skin lesions. Pemphigus is diagnosed on the basis of either IgG or complement component 3 deposits (or both) at the keratinocyte cell membrane, detected by direct immunofluorescence microscopy of a perilesional biopsy, with serum anti-Dsg1 or anti-Dsg3 antibodies (or both) detected by ELISA. Corticosteroids are the therapeutic mainstay, which have recently been complemented by the anti-CD20 antibody rituximab in moderate and severe disease. Rituximab induces complete remission off therapy in 90% of patients, despite rapid tapering of corticosteroids, thus allowing for a major corticosteroid-sparing effect and a halved number of adverse events related to corticosteroids.

Paraneoplastic pemphigus and myasthenia gravis as the first manifestations of a rare case of pancreatic follicular dendritic cell sarcoma: CT findings and review of literature

BACKGROUND

Follicular dendritic cell sarcoma (FDCS) is a rare neoplasm that originates from follicular dendritic cells in lymphoid tissue while paraneoplastic pemphigus (PNP) is an autoimmune blistering disease associated with neoplasms. Pancreatic FDCS associated with PNP and myasthenia gravis (MG) is even rarer and highly malignant. We present the clinical data, pathological materials and computed tomography (CT) features of a rare case of this disease.

CASE PRESENTATION

A 49-year-old woman presented with repeated ptosis of both eyelids, oral ulcers and erosions. Her laboratory results showed a slight elevation of CA125 and positivity of some autoimmune antibodies. CT revealed a round solid mass with central necrosis in the pancreatic tail. The solid component of the mass showed slight enhancement and serpentine feeding arteries in the arterial phase, moderate enhancement with a draining vein around the tumor in the portal venous phase and persistent enhancement in the delayed phase. Surgical resection was performed, and the pathological diagnosis was FDCS. However, the patient died of inability to excrete sputum and occlusion of the respiratory tract.

CONCLUSIONS

Pancreatic FDCS manifested as PNP and MG is very rare. Its CT features are not specific, and the disease should be differentiated from neuroendocrine tumors, solid pseudopapillary neoplasms and acinar cell carcinoma.

The role of the laboratory in the expanding field of neuroimmunology: Autoantibodies to neural targets

Accelerated identification of autoantibodies associated with previously idiopathic neurological disease has provided insights into disease mechanisms, enhanced understanding of neurological function, and opportunities for improved therapeutic interventions. The role of the laboratory in the expanding field of neuroimmunology is critical as specific autoantibody identification provides guidance to clinicians in diagnosis, prognosis, tumor search strategies, and therapeutic interventions. The number of specific autoantibodies identified continues to increase and newer testing strategies increase efficiencies in the laboratory and availability to clinicians. The need for broadly targeted efficient testing is underscored by the variability in clinical presentation and tumor associations attributable to a specific autoantibody, and conversely the various autoantibody specificities that can be the cause of a given clinical presentation. While many of the antineural antibodies were first recognized in the setting of neoplastic disease, idiopathic autoimmune neurological disease in the absence of underlying tumor is increasingly recognized. Appropriation of therapeutic modalities used to treat autoimmune disease to treat these autoantibody mediated neurological diseases has improved patient outcomes. Interaction between clinicians and laboratorians is critical to our understanding of these diseases and optimization of the clinical benefits of our increasing knowledge in neuroimmunology.

Spectrum of orocutaneous disease associations: Immune-mediated conditions

There are a number of diseases that manifest both on the skin and the oral mucosa, and therefore the importance for dermatologists in clinical practice to be aware of these associations is paramount. In the following continuing medical education series, we outline orocutaneous disease associations with both immunologic and inflammatory etiologies.

Pediatric 8p11 eosinophilic myeloproliferative syndrome (EMS): A case report and review of the literature

The 8p11 eosinophilic myeloproliferative syndrome (EMS) is an aggressive neoplasm driven by translocation of the fibroblast growth factor receptor 1 and often transforms to leukemias and lymphomas that are refractory to treatment. The first case was identified in 1983, and to date over 70 cases have been reported in the literature. Despite those reports, no consensus exists on management of this condition, and inconsistency in treatment regimens is even more pronounced in the pediatric literature. We report a case of a male infant with the 8p11 EMS, review the published pediatric experience with EMS, and discuss treatment strategies for this enigmatic hematological disorder.

Paraneoplastic Pemphigus and Autoimmune Blistering Diseases Associated with Neoplasm: Characteristics, Diagnosis, Associated Neoplasms, Proposed Pathogenesis, Treatment

Autoimmune paraneoplastic and neoplasm-associated skin syndromes are characterized by autoimmune-mediated cutaneous lesions in the presence of a neoplasm. The identification of these syndromes provides information about the underlying tumor, systemic symptoms, and debilitating complications. The recognition of these syndromes is particularly helpful in cases of skin lesions presenting as the first sign of the malignancy, and the underlying malignancy can be treated in a timely manner. Autoimmune paraneoplastic and neoplasm-associated bullous skin syndromes are characterized by blister formation due to an autoimmune response to components of the epidermis or basement membrane in the context of a neoplasm. The clinical manifestations, histopathology and immunopathology findings, target antigens, associated neoplasm, current diagnostic criteria, current understanding of pathogenesis, and treatment options for a selection of four diseases are reviewed. Paraneoplastic pemphigus manifests with clinically distinct painful mucosal erosions and polymorphic cutaneous lesions, and is often associated with lymphoproliferative neoplasm. In contrast, bullous pemphigoid associated with neoplasm presents with large tense subepidermal bullae of the skin, and mild mucosal involvement, but without unique clinical features. Mucous membrane pemphigoid associated with neoplasm is a disorder of chronic subepithelial blisters that evolve into erosions and ulcerations that heal with scarring, and involves stratified squamous mucosal surfaces. Linear IgA dermatosis associated with neoplasm is characterized by annularly grouped pruritic papules, vesicles, and bullae along the extensor surfaces of elbows, knees, and buttocks. Physicians should be aware that these autoimmune paraneoplastic and neoplasm-associated syndromes can manifest distinct or similar clinical features as compared with the non-neoplastic counterparts.

Paraneoplastic pemphigus and myasthenia gravis, associated with inflammatory pseudotumor-like follicular dendritic cell sarcoma: response to rituximab

Paraneoplastic pemphigus (PNP) is an autoimmune blistering disease associated with neoplasms. The disease is most commonly of lymphoproliferative origin and presents high mortality. We describe a patient with PNP and myasthenia gravis associated with inflammatory pseudotumor‐like follicular dendritic cell sarcoma, as well as the response to rituximab.