The mechanism of respiratory failure in paraneoplastic pemphigus

The Importance and Challenges of Early Diagnosis of Paraneoplastic Skin Syndromes in Cancer Detection-A Review

Skin paraneoplastic syndromes (SPNSs) are a group of disorders that arise as a consequence of cancer but are not directly related to the tumor mass itself. This review aims to provide a comprehensive overview of these syndromes, encompassing their pathophysiology, clinical features, diagnostic approaches, differential diagnosis, and management strategies. These syndromes, which include conditions such as Bazex syndrome, acanthosis nigricans, dermatomyositis, and necrolytic migratory erythema often manifest prior to or concurrently with a cancer diagnosis, serving as potential early warning signs of underlying malignancies. This review delves into the spectrum of SPNSs and their associations with specific cancer types. Special emphasis is placed on the critical role of dermatologists and oncologists in identifying these skin manifestations as potential markers of malignancy. By raising awareness of SPNSs, this paper highlights the pivotal importance of prompt recognition and intervention in reducing cancer-related mortality.

An Autopsy Case of Bronchiolitis Obliterans Associated With Oral Lichen Planus and Non-Hodgkin Lymphoma

We report the autopsy case of a 66-year-old woman with indolent B-cell non-Hodgkin lymphoma (NHL) who underwent repeated chemotherapy for 18 years. Two and a half years ago, she developed oral lichen planus and began corticosteroid treatment. Lichen planus recurred repeatedly with corticosteroid reduction. Obstructive ventilation impairment and respiratory failure had progressed two years ago. She was admitted to the hospital due to cytomegalovirus infection and died of respiratory failure. An autopsy revealed bronchiolitis obliterans, oral lichen planus, and recurrence of pre-existing NHL. This was a rare case of bronchiolitis obliterans with oral lichen planus and NHL.

Retroperitoneal unicentric Castleman disease presenting with paraneoplastic pemphigus

Castleman disease is a benign lymph node hyperplasia with two histological subtypes. In the case reported here, a young adult male presented with mucocutaneous lesions mimicking common dermatological conditions. Suspicion of an underlying systemic disease arose when the routine clinical care of the skin lesions failed to cure them. Immunoprecipitation and histological analysis of the lesions pointed towards paraneoplastic pemphigus. The radiological imaging of the abdomen showed a retroperitoneal tumour which supported the paraneoplastic nature of the skin disease. Preoperative biopsy of the retroperitoneal tumour could not provide a definitive diagnosis. So, complete surgical excision of the retroperitoneal tumour was undertaken and pathological evaluation led to the final diagnosis of Castleman disease. We explain how the varied atypical presentation of an underlying rare disease can lead to a delay in the diagnosis, and how we untangled it with sequential work-up leading to successful surgical excision of the disease.

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.

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

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

Paraneoplastic pemphigus presenting as a prodrome to aggressive T cell lymphoma

Paraneoplastic pemphigus (PNP) is a rare disease with an unclear mechanism of pathogenesis. We present a case of a male patient who presented with wound management after being diagnosed with Castleman disease-associated paraneoplastic pemphigus (PNP). The patient's condition was not improving; as a result, extensive workup was repeated, which confirmed the diagnosis of aggressive T cell lymphoblastic lymphoma. Our case signifies the importance of keeping a high index of suspicion for PNP-associated malignancies. This case report also adds emphasis to the diagnostic challenges faced by clinicians, making clinical correlation with multidisciplinary approach essential. Therefore, if clinically indicated, we need to revisit the diagnosis and seek alternative explanations to prevent delays in management.

Whole-Exome Sequencing Reveals the Genomic Profile and IL6ST Variants as a Prognostic Biomarker of Paraneoplastic Pemphigus-Associated Unicentric Castleman Disease

Unicentric Castleman disease (UCD) is a rare lymphoproliferative disorder. Paraneoplastic pemphigus (PNP) is a major complication associated with poor UCD prognosis. However, the genomic profiles and prognostic biomarkers of PNP-associated UCD remain unclear. In this study, we performed whole-exome sequencing analysis for 28 matched tumor-normal pairs and 9 tumor-only samples to define the genomic landscape of Chinese patients with PNP-associated UCD. An integrative analysis was performed to identify somatic variants, the mutational signatures, and key pathways in tumors. Besides, we analyzed the relationship among mutated genes, clinical characteristics, and prognosis. Sixty-one somatic mutant genes were identified in >1 patient with PNP-associated UCD. Specifically, IL6ST and PDGFRB were the most frequently mutated genes (32%), followed by DPP6 (18%) and MUC4 (18%). Signaling molecules and interactions, cellular processes, and signal transduction pathways were enriched. Furthermore, we found that poor overall survival was related to IL6ST variants (P = .02). Finally, we classified PNP-associated UCD into 4 genomic subgroups: IL6ST, PDGFRB, IL6ST-PDGFRB, and an unknown subgroup. In summary, we defined the molecular profile of PNP-associated UCD and identified a potential molecular biomarker for predicting prognosis, which may provide therapeutic targets for treating this severe disorder.

Pemphigus and pemphigoids: Clinical presentation, diagnosis and therapy

Pemphigus and pemphigoid are two potentially life-threatening groups of autoimmune diseases, characterized by autoantibodies targeting structural components of desmosomes or hemidesmosomes, respectively. Affected patients typically show itchy/painful plaques or blistering skin lesions and/or impairing mucosal blistering and erosions, which may strongly impact their quality of life. Since the milestone work of Walter Lever in 1953, who differentiated these two groups of diseases by histopathological analysis of the level of antibody-mediated skin cleavage, enormous progresses occurred. Achievements made in laboratory diagnostics now allow to identify antigen specific structural proteins of the skin that are targeted by pathogenic autoantibodies. These progresses were accompanied by an increased understanding of the pathogenesis of these diseases thanks to the establishment of animal models reproducing disease and on studies on skin and blood of affected individuals, which have been leading to novel and disease-specific treatments. Yet, given their phenotypical overlap with more common dermatological diseases, correct diagnosis and appropriate treatment are often delayed, in some cases leading to irreversible sequelae, including organ dysfunction (i.e., loss of vision in mucous membrane pemphigoid). Here, we provide a concise overview of the clinical appearance, diagnosis and therapeutic management of pemphigus and pemphigoid diseases.

Pemphigus- und Pemphigoid-Erkrankungen: Klinik, Diagnostik und Therapie: Pemphigus and pemphigoids: Clinical presentation, diagnosis and therapy

Pemphigus und Pemphigoid sind seltene Autoimmunkrankheiten der Haut mit potenziell lebensbedrohlichem Verlauf. Autoantikörper gegen epidermale und junktionale Strukturproteine (Desmosomen sowie Hemidesmosomen) führen bei Betroffenen typischerweise zu juckenden, schmerzhaften Plaques oder Blasen an der Haut und/oder Blasenbildung und Erosionen der Schleimhäute mit möglicher Einschränkung der Lebensqualität. Seit der bahnbrechenden Arbeit von Walter Lever im Jahr 1953, dem es gelang, mittels histopathologischer Untersuchung diese beiden Krankheitsgruppen anhand des Musters der Antikörper‐vermittelten Blasenbildung zu differenzieren, wurden enorme Fortschritte im Verständnis der Erkrankungen erzielt. Die Errungenschaften in der Labordiagnostik ermöglichten die Identifikation von Zielstrukturen zur präzisen Unterscheidung verschiedener Varianten der bullösen Autoimmunerkrankungen. Diese Fortschritte gingen dank der Entwicklung von Tiermodellen mit einem besseren Verständnis der Pathogenese einher. Außerdem haben Studien an Haut und Blut betroffener Patienten zu neuen und krankheitsspezifischen Behandlungen geführt. Aufgrund ihrer Seltenheit und der klinischen Ähnlichkeit mit anderen dermatologischen Erkrankungen verzögern sich die korrekte Diagnosestellung und die Einleitung einer entsprechenden Therapie häufig, was in einigen Fällen zu irreversiblen Folgeerscheinungen, einschließlich Funktionsstörungen von Organen (zum Beispiel Verlust des Sehvermögens beim Schleimhautpemphigoid) führt. Wir geben hier einen Überblick über das klinische Erscheinungsbild, den Diagnosealgorithmus und das therapeutische Management von Pemphigus‐ und Pemphigoid‐Erkrankungen.

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: Diagnostic mimics, confounders and management challenges in a series of five long-term survivors from a single centre

We present a series of five cases who presented to our institution with treatment-refractory mucosal ulceration, all of whom were subsequently diagnosed with paraneoplastic pemphigus (PNP). This case series highlights the diagnostic and treatment considerations for PNP - in particular, the steroid-dependent, recalcitrant, polymorphic manifestations; the combination of histopathological and clinical findings that may overlap with clinically similar diseases, for example, pemphigus vulgaris and lichen planus; the importance of immunopathological findings for its diagnosis, and the need for surveillance and management of life-threatening bronchiolitis obliterans.

Classification and Antigen Molecules of Autoimmune Bullous Diseases

Autoimmune bullous diseases (AIBDs), which are a group of tissue-specific autoimmune diseases of the skin, present with various blistering lesions on the skin and mucous membranes, and show autoantibodies of IgG, IgA and IgM against epidermal cell surfaces and basement membrane zone. To date, AIBDs have been classified into a number of distinct subtypes by clinical and histopathological findings, and immunological characteristics. In addition, various biochemical and molecular biological studies have identified various novel autoantigens in AIBDs, which has resulted in proposals of new subtypes of AIBDs. In this article, we summarized various distinct AIBDs, and proposed the latest and most comprehensive classification of AIBDs with their autoantigen molecules.

Paraneoplastic pemphigus and Castleman's disease: a case report and a revision of the literature

BACKGROUND

In literature, a few reports described an association between paraneoplastic pemphigus (PNP) and Castelman's disease (CD), but no consensus have been proposed for the diagnostic-therapeutical approach. Aim of this study is to present a case report and explore the relationship between PNP and CD in pediatric patients, focusing on clinical manifestations, histopathological findings, treatment and outcome to find elements for an early diagnosis.

CASE PRESENTATION

We present the clinical case of a 13 years old girl with a challenging diagnosis of PNP and CD who underwent therapy at first with Rituximab and then with Siltuximab, for the control of symptoms.

CONCLUSIONS

Reviewing literature, 20 clinical cases have been described in the pediatric age. Diagnosis may be challenging, requiring an average of 3 months (range from 3 weeks to 2 years). In all cases, the initial manifestations were mucocutaneous lesions, especially oral lesions with poor response to conventional treatment. Systemic symptoms may be present as well. Therapeutical approach is still discussed with no consensus. Almost all patients received corticosteroids with poor response. Other drugs including azathioprine, methotrexate, cyclosporine and monoclonal antibodies have been evaluated for the control of the disease. Further studies and experimental trials urge to define the diagnostic criteria and therapy protocol.

A first case of successful using of ibrutinib in treating paraneoplastic pemphigus related bronchiolitis obliterans concurrent with CLL

Paraneoplastic pemphigus (PNP) is a rare life-threatening disease which always associated with an underlying neoplasm. Tumor-related PNP most commonly precedes the detection of a hematological malignancy, with some cases seen during disease remission following cytotoxic drug therapy or radiotherapy. The lung is the most frequently-involved site in PNP, second only to the eyes, and involvement is seen in 59.2% to 92.8% of PNP cases. Bronchiolitis obliterans (BO) is the end stage of respiratory involvement and is regarded as life-threatening. The key point in treatment of PNP is to control the associated underlying hematologic neoplasia. High-dose systemic corticosteroids combined with other immunosuppressants are considered the first line of treatment. Other therapies that have shown beneficial effects include plasmapheresis, intravenous immunogloblin (IVIG), and more recently, daclizumab, alemtuzumab, and rituximab. There is no effective treatment for BO with PNP, and suppression of the cellular immune response may be necessary. Patients with PNP-BO associated with lymphoma mostly die within approximately 1 year. Herein, we reported a patient who diagnosed with PNP-BO concurrent with chronic lymphocytic leukemia. He was successful treated with ibrutinib and had achieved the longest survival which suggested that ibrutinib may be the best treatment choice for such patient.

T cell autoimmunity and immune regulation to desmoglein 3, a pemphigus autoantigen

Pemphigus is a life-threatening autoimmune bullous disease mediated by anti-desmoglein IgG autoantibodies. Pemphigus is mainly classified into three subtypes: pemphigus vulgaris, pemphigus foliaceus, and paraneoplastic pemphigus. The pathogenicity of autoantibodies has been extensively studied. Anti-human CD20 antibody therapy targeting B cells emerged as a more effective treatment option compared to conventional therapy for patients with an intractable disease. On the other hand, autoreactive T cells are considered to be involved in the pathogenesis based on the test results of human leukocyte antigen association, autoreactive T cell detection, and cytokine profile analysis. Research on the role of T cells in pemphigus has continued to progress, including that on T follicular helper cells, which initiate molecular mechanisms involved in antibody production in B cells. Autoreactive T cell research in mice has highlighted the crucial roles of cellular autoimmunity and improved the understanding of its pathogenesis, especially in paraneoplastic pemphigus. The mouse research has helped elucidate novel regulatory mechanisms of autoreactive T cells, such as thymic tolerance to desmoglein 3 and the essential roles of regulatory T cells, Langerhans cells, and other molecules in peripheral tissues. This review focuses on the immunological aspects of autoreactive T cells in pemphigus by providing detailed information on various related topics.

Dermatological manifestations of hematologic neoplasms. Part II: nonspecific skin lesions/paraneoplastic diseases

Cutaneous manifestations occur in the course of hematologic malignancies and precede, accompany or occur late in relation to the diagnosis. They result from paraneoplastic phenomena, tumor infiltrations, immunosuppression resulting from the hematologic disease itself or its treatment. The dermatologist must be aware of these conditions that may be helpful both in the diagnosis of the underlying disease and in reducing patient morbidity. This review (part II) addresses the paraneoplastic dermatological changes associated with systemic hematologic malignancies.

Oral presentation of paraneoplastic pemphigus as the first sign of tonsillar HPV associated squamous cell carcinoma. A case report

BACKGROUND

Paraneoplastic pemphigus (PNP) in the oral cavity is a rare variant of blistering pemphigus disease closely associated with mostly malignant tumors. The diagnosis may even precede an underlying malignancy enabling early detection. Here, we describe a previously unreported case of PNP associated with HPV-related tonsillar squamous cell carcinoma.

METHODS AND RESULTS

A 50-year-old woman was referred to a dentist because of painful oral lesions resembling aphthae major and minor. Later, blisters appeared and an incisional biopsy was performed. Histological examination revealed an unusual coexistence of subepithelial and intraepithelial blisters raising suspicion of paraneoplastic pemphigus. The patient underwent 18F-FDG PET/MRI, showing a metabolically active process in the left palatal tonsil. Diagnostic biopsy revealed HPV type 16 associated tonsillar squamous cell carcinoma. A left tonsillectomy with elective left-sided neck dissection was performed. The postoperative period was complicated by bilateral fluidothorax. Two weeks after radical tumor removal, the mucosal and skin lesions of PNP disappeared. The patient currently shows no evidence of recurrence either of malignancy or PNP eight months after the surgery.

CONCLUSION

PNP is a rare autoimmune blistering disease characterized by polymorphous cutaneous and mucosal lesions associated with internal neoplasms including HPV associated squamous cell carcinoma of a tonsil. In order to identify an occult malignancy, a whole-body PET/CT or PET/MRI scan is recommended. Rarely, accurate patient management may depend on the dentist being familiar with this entity and on interdisciplinary cooperation involving dermatologist, radiologist, pathologist, and pneumologist. A strict patient follow-up is indicated.

Pemphigoid of the pulmonary system (POPS): A review of a less recognized feature

This review of Pemphigoid of the Pulmonary System (POPS) is a comprehensive description of pulmonary involvement in patients with mucous membrane pemphigoid (MMP), which is an orphan autoimmune blistering disease. The objective of the review was to analyze clinical features of pulmonary involvement in MMP. This POPS review is a case series in which multiple search engines were utilized from inception to June 2022 for cases of MMP with biopsy and immunopathology proven tracheal and bronchial pemphigoid. Clinical profiles prior to pulmonary involvement, bronchoscopy findings, clinical course and therapy were recorded and cause of death was analyzed. Patients with documented MMP who developed tracheal, bronchial and pulmonary involvement were included in the POPS review. Histology and immunopathology documentation were essential diagnostic criteria. Comparison groups were not possible. Patients were treated with immunosuppressive therapy. Some required surgical interventions. Six of the 11 patients attained complete or partial remission on or off therapy. Five patients died from pulmonary complications. The POPS review had six females and five males. The mean age at onset was 20 years (range 4-76), while 80% of the patients were under 40 years. All had severe widespread MMP involving three to five mucosal tissues. 100% had oral, 82% had ocular and cutaneous involvement. Pulmonary involvement occurred at 24 mo (range 2-372) after the onset of MMP. Bronchoscopy revealed acute inflammation during active disease and scarring of the trachea and bronchi in the later stages. Systemic infections occurred in 45%, while pulmonary infection occurred in 36%. Mortality due to respiratory failure, at the median age of 20 years (range 18-76), occurred in 45% of the patients, and was considered disease related. In spite of the young age, while there are some similarities in the clinical profile and response to systemic therapy, there are definitive differences from other patients with MMP. Early diagnosis with appropriate management could produce better clinical outcomes and prevent mortality in this orphan disease. Consequently, there is a critical need for early identification and diagnosis of POPS.

Paraneoplastic Pemphigus Autoantibodies Against C-terminus of Desmoplakin Induced Acantholysis In Vitro and In Vivo

Paraneoplastic pemphigus (PNP) is an autoimmune bullous disease associated with underlying neoplasms and characterized by antibodies against desmoglein 3 (Dsg 3) and plakins. Autoantibodies against desmoglein 3 in sera of patients with PNP have been proven to cause acantholysis in vivo in neonatal mice. As a member of the plakin family, autoantibodies against desmoplakin were detected frequently by immunoprecipitation in the sera of PNP. The recombinant C-terminus of desmoplakin was expressed and purified to adsorb the specific autoantibodies against the C-terminus of desmoplakin. In vitro dispase-dependent keratinocyte dissociation assay and in vivo IgG passive transfer into neonatal mice assay were performed, followed by the electronic microscopy examination and TUNEL assay. We found that anti-C terminus of desmoplakin autoantibodies caused blisters and acantholysis in mice skin at a dose-dependent manner. Moreover, dissociated fragments were observed after incubation with the purified IgG against desmoplakin, compared with normal human IgG (P-value =0.0207). The electronic microscopy examination showed the disconnection of keratin intermediate filaments from desmosomes. Lastly, apoptosis of keratinocytes in the TUNEL assay was all detected in the skins of neonatal mice after injection of the anti-C terminus of desmoplakin autoantibodies. Taken together, the study suggests that autoantibodies against the C-terminus of desmoplakin might be pathogenic in PNP.

Clinical and pathological features of bronchiolitis obliterans requiring lung transplantation in paraneoplastic pemphigus associated with Castleman disease

Summary at a glance

Bronchiolitis obliterans in paraneoplastic pemphigus associated with Castleman disease possesses the progressive nature even when it is treated with intensive medical therapy. Antibodies were at least in low titers before the Lung transplant and remain negative after the procedure. Explanted lungs showed coexistence of cellular destructive bronchiolitis and constrictive bronchiolitis.

Background

Bronchiolitis obliterans (BO) in paraneoplastic pemphigus (PNP) associated with Castleman disease (CD) possesses the progressive nature of pulmonary disease even when it is treated with intensive medical therapy. Lung transplantation (LT) offers an acceptable form of treatment.

Methods

We conducted a retrospective study of two cases of BO in PNP associated with CD who underwent LT between March 2017 and March 2020 at the China‐Japan Friendship Hospital. We also included one case from the literature.

Results

In this patient series, PNP was the primary clinical presentation in all patients, and it was accompanied by respiratory symptoms before/after CD excision. In spite of being treated with various combinations of immunosuppressive and anti‐inflammatory agents, the patients had great or total improvement in mucosal erosions, whereas their pulmonary function test (PFT) deteriorated gradually or sharply. The duration times from disease onset to timing of LT were 1, 2 and 5 years. All antibodies were negative or were present at low titers before the LT procedure and remain negative after the procedure. The histopathological features of explanted lungs showed cellular and coexistent destructive bronchiolitis and constrictive bronchiolitis in two cases. Granulation with numerous foamy macrophages, scattered giant cells and cholesterol clefts were especially prominent in case one.

Conclusion

BO in PNP associated with CD had poor clinical outcomes. LT was preferable choice in end‐stage BO when PNP and CD were controlled.

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.

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.

Bilateral lung transplantation for Castleman disease with end-stage bronchiolitis obliterans

Bronchiolitis obliterans (BO) is a severe complication of Castleman disease (CD), a rare lymphoproliferative disease with unclear pathogenesis. Currently, there are no reports on the safety or outcomes of bilateral lung transplantation in patients with BO due to CD. This study aimed to characterize the clinical manifestations and features of BO and CD. We retrospectively analyzed the medical records of six consecutive patients with BO and CD who underwent bilateral lung transplantation between December 2012 and December 2020. The average age of patients at lung transplantation was 33 ± 15 years, and the age range of patients at diagnosis of CD was about 9-56 years. The body mass index was 15.2 ± 1.9 kg/m² . The average time from diagnosis to lung transplantation was 4.1 ± 2.7 years. All the patients had unicentric CD (UCD); five had concomitant paraneoplastic pemphigus, and four received extracorporeal membrane oxygenation during surgery. The average hospital stay was 51 ± 53 days. Infection was the most common postoperative complication. CD did not recur in any of the patients. Thus, bilateral lung transplantation is a viable and safe treatment for selected patients with CD and BO, which can improve the quality of life and prolong survival.

Paraneoplastic pemphigus caused by pre-existing stroma-rich variant of Castleman disease: from a pathologist's point of view

A young woman presented with mucocutaneous blisters and ulcerating lesions, and was diagnosed with erythrodermic pemphigus complicated by bronchiolitis obliterans. Her clinical condition did not improve on immunosuppressive therapy. She had a history of an asymptomatic retroperitoneal mass, presumed to be a dermoid cyst, followed up clinically. Due to the pre-existing nature of the retroperitoneal mass, the paraneoplastic nature of the pemphigus was initially not recognised, but after a multidisciplinary team meeting a biopsy was performed. Histology revealed a rare stroma-rich variant of Castleman disease with a prominent stroma demonstrating a myoid phenotype. Resection of the retroperitoneal tumour resulted in resolution of the cutaneous blisters. This emphasises the importance to consider paraneoplastic disease in treatment-resistant pemphigus as surgical removal of the tumour forms the mainstay of therapy. The differential diagnosis should include Castleman disease and careful evaluation of histology is essential with the awareness of this rare stroma-rich variant.

Clinicians' pearls and myths in pemphigus

Pemphigus comprises a heterogeneous group of autoimmune blistering diseases, which can affect both skin and mucous membranes, especially oral mucosa. This group of diseases shows usually a chronic-relapsing course. Since pemphigus is a rare disease, the diagnosis is often delayed, because it is based upon the recognition of consistent clinical, histologic, and direct immunofluorescence findings, as well as indirect immunofluorescence, and/or enzyme-linked immunosorbent assay. Usually the patients are treated for multiple other conditions before starting the correct therapy, leading to a critical reduction of the patients' quality of life. This review is a succinct compilation of pearls gathered from clinical experience in pemphigus and the myths that may have influenced everyday practice but have been proven false. This review provided a selection of such dilemmas and controversies, focusing on myths and pearls that can help young dermatologist in the clinic, while also dispelling them.

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.

Paraneoplastic Pemphigus Involving the Respiratory and Gastrointestinal Mucosae

Paraneoplastic pemphigus (PNP), an autoimmune mucocutaneous disorder involving the oral and bronchial mucosae, is a rare complication of hematologic malignancy. Serologically, serum autoantibodies against varied desmosome-related proteins are of notice. PNP is often lethal due to bronchiolitis obliterans and opportunistic infection. A 70-year-old Japanese male complained of dry cough, stomatitis, and sore throat. The lips and oral mucosa were severely eroded, and skin eruptions were seen on the chest and abdomen. The biopsy features were consistent with PNP, and the deposition of IgG and IgM was shown on the plasma membrane of the involved keratinocytes. Serological studies demonstrated autoantibodies to desmoglein-3, desmocollins-2 and -3, bullous pemphigoid antigen-1, envoplakin and periplakin. Systemic evaluation disclosed mantle cell lymphoma, stage 4B. After chemotherapy, partial remission was reached. PNP was treated with methylprednisolone and intravenous immunoglobulins, and the oral lesion only temporarily responded. He died of respiratory failure two months after onset. Autopsy revealed residual indolent lymphoma and systemic opportunistic infections. Aspergillus colonized the eroded bronchial/bronchiolar mucosa, associated with extensive vascular invasion. Coinfection of cytomegalovirus (CMV) and Pneumocystis jirovecii caused interstitial pneumonia. The oropharyngeal, respiratory, esophageal, and gastrointestinal mucosae were diffusely infected by CMV. Bronchiolitis obliterans was observed in the peripheral lung. PNP-related acantholysis-like lesions were microscopically identified in the bronchial and gastrointestinal mucosa. IgG deposition and cleaved caspase-3-immunoreactive apoptotic cell death were proven in the involved mucosal columnar cells. Pathogenesis of the mucosal involvement is discussed.

Autoimmunity and immunological tolerance in autoimmune bullous diseases

Autoimmune diseases are devastating conditions in which the immune system is directed against the host, leading to life-threatening destruction of organs. Although autoantigens are ill-defined in most autoimmune diseases, this is not the case in the skin. Autoimmune bullous diseases have been extensively studied with detailed characterization of autoantigens, the epitopes that are targeted, and the mechanisms of action that mediate autoimmune tissue destruction. Pemphigus is an autoimmune bullous disease caused by circulating IgG that targets two desmosomal proteins, desmoglein 1 and 3, which are crucial for cell-cell adhesion of keratinocytes. Binding of auto-antibodies to desmogleins impairs keratinocyte adhesion, leading to severe blistering disease. Mouse models that recapitulate the human disease have been instrumental in elucidating the detailed pathophysiology. Taking advantage of the fact that desmogleins are specifically targeted in pemphigus, studying humoral and cellular autoimmunity against these autoantigens provides us with an opportunity to understand not only the effector mechanisms of B and T cells in mediating pathology but also how autoreactive lymphocytes are regulated during development in the thymus and post-development in the periphery. This review introduces pemphigus and its subtypes as prototypic autoimmune diseases from which recent basic and translational developments should provide insight into how autoimmunity develops.

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.

Mucocutaneous Diseases

Mucocutaneous diseases affecting the oral cavity are predominantly immune mediated or inflammatory. Three of the most common and clinically significant conditions are reviewed in this article: lichen planus, pemphigus vulgaris, and mucous membrane pemphigoid. Because oral manifestations may be the first or only manifestation of mucocutaneous diseases, oral health professionals play a critical role in the early diagnosis and multidisciplinary management of these conditions.

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: Paraneoplastic Autoimmune Disease of the Skin and Mucosa

Paraneoplastic pemphigus (PNP) is a rare but life-threatening mucocutaneous disease mediated by paraneoplastic autoimmunity. Various neoplasms are associated with PNP. Intractable stomatitis and polymorphous cutaneous eruptions, including blisters and lichenoid dermatitis, are characteristic clinical features caused by humoral and cell-mediated autoimmune reactions. Autoreactive T cells and IgG autoantibodies against heterogeneous antigens, including plakin family proteins and desmosomal cadherins, contribute to the pathogenesis of PNP. Several mechanisms of autoimmunity may be at play in this disease on the type of neoplasm present. Diagnosis can be made based on clinical and histopathological features, the presence of anti-plakin autoantibodies, and underlying neoplasms. Immunosuppressive agents and biologics including rituximab have been used for the treatment of PNP; however, the prognosis is poor due to underlying malignancies, severe infections during immunosuppressive treatment, and bronchiolitis obliterans mediated by autoimmunity. In this review, we overview the characteristics of PNP and focus on the immunopathology and the potential pathomechanisms of this disease.

Comorbidities in Dermatology: What's Real and What's Not

Comorbidities affecting dermatologic patients are of significant importance to providers and highly relevant for appropriate patient counseling, screening practices, prevention, and treatment. This article seeks to highlight several of the newest findings in the literature regarding comorbidities associated with dermatologic diseases including atopic dermatitis, hidradenitis suppurativa, alopecia areata, chronic urticaria, and the pemphigus family of immunobullous diseases. Further investigation is needed for associations between atopic dermatitis and pancreatic cancer and pemphigus family diseases and chronic obstructive pulmonary disease in order to better characterize the strength of these associations and clinical relevance.

[Paraneoplastic pemphigus: Retrospective study of a case series]

CONTEXT

Paraneoplastic pemphigus (PNP) is a rare condition associated with poor prognosis. It associates polymorphic mucocutaneous manifestations with neoplasia. Diagnosis is difficult because of the various clinical and histological features involved and the lack of specificity of immunological examinations.

METHODS

We retrospectively analyzed the records of patients presenting with PNP in the Poitou-Charentes region between 2000 and 2015.

RESULTS

Seven patients were included. They presented 9 neoplasias (1 lymphoma, 1 melanoma, and 7 carcinomas) diagnosed from 4 months before to 25 months after the occurrence of cutaneous (6/7) and/or mucosal (6/7) polymorphic lesions. Histological examination revealed epidermal acantholysis (7/7), keratinocytic necrosis (4/7), and interface lichenoid dermatitis (5/7). Intercellular deposits of IgG and C3 or along the dermo-epidermal junction were detected with direct immunofluorescence (IF) (7/7). Four of 6 patients tested had positive indirect IF on rat bladder epithelium. Follow-up ranged from 1-132 months with a one-year survival of 85.7%.

DISCUSSION

The clinical and histopathological presentations observed in our patients were polymorphic, with overlap between the clinical and histological features of PNP and classical pemphigus. Prognosis and survival appear better in our series than in the literature. It is possible that in some cases, the association of pemphigus with neoplasia was fortuitous, which might account for the better prognosis. A new consensus on the diagnostic criteria for PNP is needed to help practitioners to consensually diagnose it for prognostic or therapeutic trials.

Unicentric castleman disease complicated by paraneoplastic bronchiolitis obliterans and pemphigus

Bronchiolitis obliterans (BO) and paraneoplastic pemphigus are rare and ominous complications of Castleman disease. Collectively, these processes have been reported as part of paraneoplastic autoimmune multiorgan syndrome (PAMS), and they can occur in the setting of various hematologic malignant tumors, carcinoid tumors, and melanoma. Irrespective of the underlying malignancy driving PAMS, the clinical outcomes are uniformly poor, and there are no standard treatment regimens, given the clinical rarity of the syndrome. We describe 2 patients with unicentric Castleman disease complicated by paraneoplastic pemphigus and bronchiolitis obliterans. In addition to primary surgical resection for Castleman disease, we also used therapy from a treatment protocol used for bronchiolitis obliterans resulting from hematopoietic stem cell transplant (HSCT). We were able to treat the patients using intravenous immunoglobulin; rituximab; fluticasone, azithromycin, and montelukast (FAM); and rosuvastatin therapy. One patient demonstrated a favorable response, while the other demonstrated minimal response to this therapy.

COPD and lung cancer in patients with pemphigus- a population based study

BACKGROUND

Recent evidence indicates that autoimmunity may contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD). COPD was observed at higher frequency in patients with several autoimmune diseases. The association between pemphigus and COPD has not been evaluated in the past.

OBJECTIVES

To study the association between pemphigus and COPD using a large-scale real-life computerized database.

METHODS

A cross-sectional study was conducted comparing pemphigus patients with age-, sex- and ethnicity-matched control subjects regarding the prevalence of COPD and lung cancer. Chi-square and t-tests were used for bivariate analysis, and logistic regression model was used for multivariate analysis. The study was performed utilizing the computerized database of Clalit Health Services ensuring 4.4 million subjects.

RESULTS

A total of 1985 pemphigus patients and 9874 controls were included in the study. The prevalence of COPD was greater in patients with pemphigus as compared to the control group (13.4% vs. 10.1%, respectively; P < 0.001). In a multivariate analysis adjusting for smoking and other confounding factors, pemphigus was significantly associated with COPD (OR, 1.312-1. 5) but not with lung cancer. Study findings were robust to sensitivity analysis that included patients under pemphigus-specific treatments.

CONCLUSIONS

A significant association was found between COPD and pemphigus. Physicians treating patients with pemphigus might be aware of this possible association. This observation may further support the hypothesis that COPD has an autoimmune component.