A Global View of Pemphigus: Geographical Variations.

Pemphigus, an autoimmune intraepidermal bullous disease group with roughly eight distinct forms, includes pemphigus vulgaris (PV) and pemphigus foliaceus (PF) as its predominant global forms. Despite the increased utilization of global health records and reporting systems, epidemiological data remain limited and poorly categorized. Therefore, this study aimed to conduct a review to track, identify, and characterize cases of PV and PF published and categorized worldwide. A research question was formulated; studies were selected based on the inclusion criteria; and data from these publications were systematically collected, summarized, and presented using narrative descriptions. The search strategy yielded 3,212 articles, of which 95 underwent critical analysis and data extraction. Studies from 52 countries contributed to the dataset, covering various pemphigus variants. Notably, only two countries, Iran (18.87%) and South Korea (11.43%), accounted for approximately a third of the reported PV cases, while Brazil contributed 40.25% of the foliaceus variants cases documented in the literature. These findings offer valuable insights into the global distribution of pemphigus and inform future research and healthcare efforts.

Ultrastructural skin alterations of healthy subjects with anti-desmoglein 1 antibodies in endemic areas to pemphigus foliaceus: A case series.

Background: Endemic pemphigus foliaceus and endemic pemphigus vulgaris are autoimmune dermatologic disorders endemic to the Peruvian Amazon. Objective: To determine the ultrastructural skin alterations of three healthy subjects with anti DSG-1 antibodies in areas endemic to pemphigus foliaceus and pemphigus vulgaris in the Peruvian Amazon. Patients and methods: Case series carried out from data of three clinically healthy subjects positive to anti DSG-1 antibodies, from Peru. This study consists of a sub-analysis of data gathered in a previous study. Results: Ultrastructural results are presented from the skin biopsies of three clinically healthy patients positive to anti-desmoglein 1 (DSG-1) antibodies. High Resolution Optical Microscopy (HROM) showed the absence of acantholysis. Transmission Electron Microscopy (TEM) showed the widening of intercellular space between keratinocytes, the presence of vacuoles in intercellular space with granular material and cytoplasmic vacuolization, loss of desmosome structure, loss of normal distribution among tonofilaments and lateral separation among cells in the stratum basale. Conclusion: According to our results, healthy subjects that present anti-desmoglein 1 antibodies can develop ultrastructural alterations that are visible through transmission electron microscopy but not through conventional optical microscopy.

Genetic Associations and Differential mRNA Expression Levels of Host Genes Suggest a Viral Trigger for Endemic Pemphigus Foliaceus.

The long search for the environmental trigger of the endemic pemphigus foliaceus (EPF, fogo selvagem) has not yet resulted in any tangible findings. Here, we searched for genetic associations and the differential expression of host genes involved in early viral infections and innate antiviral defense. Genetic variants could alter the structure, expression sites, or levels of the gene products, impacting their functions. By analyzing 3063 variants of 166 candidate genes in 227 EPF patients and 194 controls, we found 12 variants within 11 genes associated with differential susceptibility (p < 0.005) to EPF. The products of genes TRIM5, TPCN2, EIF4E, EIF4E3, NUP37, NUP50, NUP88, TPR, USP15, IRF8, and JAK1 are involved in different mechanisms of viral control, for example, the regulation of viral entry into the host cell or recognition of viral nucleic acids and proteins. Only two of nine variants were also associated in an independent German cohort of sporadic PF (75 patients, 150 controls), aligning with our hypothesis that antiviral host genes play a major role in EPF due to a specific virus−human interaction in the endemic region. Moreover, CCL5, P4HB, and APOBEC3G mRNA levels were increased (p < 0.001) in CD4+ T lymphocytes of EPF patients. Because there is limited or no evidence that these genes are involved in autoimmunity, their crucial role in antiviral responses and the associations that we observed support the hypothesis of a viral trigger for EPF, presumably a still unnoticed flavivirus. This work opens new frontiers in searching for the trigger of EPF, with the potential to advance translational research that aims for disease prevention and treatment.

Extrusion of pilosebaceous units into blisters of patients affected by a new variant of endemic pemphigus in El Bagre, Colombia, South America.

BACKGROUND: A new variant of endemic pemphigus foliaceus is present in El Bagre, Colombia, and surrounding municipalities (El Bagre-EPF) that affects the skin and in some presentations affects other organs with autoantibodies directed against cell junctions. METHODS: We studied 200 El Bagre-EPF patient perilesional skin biopsies, as well as 200 skin biopsies from normal controls in the endemic area. RESULTS: We observed blister extrusions of sebaceous glands or entire pilosebaceous units via the isthmus in 23% of the patients and not in the controls. CONCLUSIONS: The extrusion of hair follicular unit contents is consistent with our previous pathologic findings of autoreactivity to these units, and their observed clinical decrease in patients affected by El Bagre-EPF.

Involvement of the Areae Compositae of the Heart in Endemic Pemphigus Foliaceus.

BACKGROUND: A new variant of endemic pemphigus foliaceus in El Bagre (El Bagre-EPF), Colombia, South America, shares features with Senear-Usher syndrome and occurs in an endemic fashion. Patients affected by El Bagre-EPF have heterogeneous antigenic reactivity not only to the skin but to other organs, including the heart. Here we test for autoantibodies to the areae compositae of the heart (structure consisting of typical desmosomal amalgamated fascia adherens molecules) and evaluate any possible clinical correlation. METHODS: A case-control study comparing 45 patients and 45 controls from the endemic area, matched by demographics including age, gender, weight, work activities, and comorbidities, was performed. Direct and indirect immunofluorescence, immunohistochemistry, confocal microscopic studies, and echocardiogram studies were completed. RESULTS: The main clinical abnormally seen in the El Bagre-EPF patients was left ventricular hypertrophy in 15/45 patients, compared with no such findings in the control population (P < 0.1). Seventy percent of El Bagre-EPF patients and none of the controls displayed polyclonal autoreactivity using different immunoglobulins and complement to the areae compositae of the heart using different methods and antibodies (P < 0.1). CONCLUSIONS: Patients affected by El Bagre-EPF demonstrated autoantibodies to the areae compositae of the heart. This finding was associated with left ventricular hypertrophic cardiomyopathy. The areae compositae may play a role in cell junction tension and the El Bagre-EPF patients' autoantibodies possibly disrupting these junctions and thereby contributing to the left ventricular hypertrophy.

Membrane attack complex (C5b-9 complex or Mac), is strongly present in lesional skin from patients with endemic pemphigus foliaceus in El Bagre, Colombia.

BACKGROUND: El Bagre endemic pemphigus foliaceus (El Bagre-EPF) is a new variant of endemic pemphigus foliaceus present in the El Bagre area of Colombia, South America. Here, we investigate the presence of complement/C5-b9 in lesional skin of patients and matched controls from the endemic area. We also aim to compare the patient's autoantibody levels using indirect immunofluorescent titers (IIF) and correlate with the lesional presence of complement/C5b-9. METHODS: A case-control study was carried out by testing for the presence of complement/C5b-9 in lesional skin in 43 patients affected by El Bagre-EPF, as well as 43 matched, healthy controls from the endemic area. Skin biopsies were obtained and evaluated via hematoxylin and eosin staining, and immunohistochemistry. RESULTS: The presence of complement/C5b-9 was observed in all cases of the patients affected by El Bagre-EPF and was not observed in the controls from the endemic area (P < 0.001). The patients' autoantibody titers utilizing IIF for IgG and IgM showed correlation between higher autoantibody titers and stronger intensity of staining with complement/C5-b9 staining (P < 0.001). CONCLUSION: Patients affected by El Bagre-EPF have lesional deposition of complement/C5b, which correlates with disease severity and previously established serologies.

Subclinical oral involvement in patients with endemic pemphigus foliaceus.

BACKGROUND: We have described a variant of endemic pemphigus foliaceus (EPF) in El Bagre area known as pemphigus Abreu-Manu. Our previous study suggested that Colombian EPF seemed to react with various plakin family proteins, such as desmoplakins, envoplakin, periplakin BP230, MYZAP, ARVCF, p0071 as well as desmoglein 1. OBJECTIVES: To explore whether patients affected by a new variant of endemic pemphigus foliaceus (El Bagre-EPF) demonstrated oral involvement. MATERIALS AND METHODS: A case-control study was done by searching for oral changes in 45 patients affected by El Bagre-EPF, as well as 45 epidemiologically matched controls from the endemic area matched by demographics, oral hygiene habits, comorbidities, smoking habits, place of residence, age, sex, and work activity. Oral biopsies were taken and evaluated via hematoxylin and eosin staining, direct immunofluorescence, indirect immunofluorescence, confocal microscopy, and immunohistochemistry. RESULTS: Radicular pieces and loss of teeth were seen in in 43 of the 45 El Bagre-EPF patients and 20 of the 45 controls (P < 0.001) (confidence interval [CI] 98%). Hematoxylin and eosin staining showed 23 of 45 El Bagre-EPF patients had corneal/subcorneal blistering and lymphohistiocytic infiltrates under the basement membrane zone and around the salivary glands, the periodontal ligament, and the neurovascular bundles in all cell junction structures in the oral cavity; these findings were not seen in the controls (P < 0.001) (CI 98%). The direct immunofluorescence, indirect immunofluorescence, confocal microscopy, and microarray staining displayed autoantibodies to the salivary glands, including their serous acini and the excretory duct cell junctions, the periodontal ligament, the neurovascular bundles and their cell junctions, striated muscle and their cell junctions, neuroreceptors, and connective tissue cell junctions. The autoantibodies were polyclonal. IgA autoantibodies were found in neuroreceptors in the glands and were positive in 41 of 45 patients and 3 of 45 controls. CONCLUSIONS: Patients affected by El Bagre-EPF have some oral anomalies and an immune response, primarily to cell junctions. The intrinsic oral mucosal immune system, including IgA and secretory IgA, play an important role in this autoimmunity. Our data contradict the hypothesis that pemphigus foliaceus does not affect the oral mucosa due to the desmoglein 1-desmoglein 3 compensation.

Cardiac rhythm and pacemaking abnormalities in patients affected by endemic pemphigus in Colombia may be the result of deposition of autoantibodies, complement, fibrinogen, and other molecules.

BACKGROUND: We previously showed that one-third of patients affected by endemic pemphigus foliaceus in El Bagre, Colombia (El Bagre-EPF), display autoreactivity to the heart. OBJECTIVE: The purpose of this study was to investigate rhythm disturbances with the presence of autoantibodies and correlate them with ECG changes in these patients. METHODS: We performed a study comparing 30 patients and 30 controls from the endemic area, matched by demographics, including age, sex, weight, work activities, and comorbidities. ECG as well as direct and indirect immunofluorescence, immunohistochemistry, and confocal microscopic studies focusing on cardiac node abnormalities were performed. Autopsies of 7 patients also were reviewed. RESULTS: The main ECG abnormalities seen in the El Bagre-EPF patients were sinus bradycardia (in one-half), followed by left bundle branch block, left posterior fascicular block, and left anterior fascicular block compared with the controls. One-third of the patients displayed polyclonal autoantibodies against the sinoatrial and/or AV nodes and the His bundle correlating with rhythm anomalies and delays in the cardiac conduction system (P <.01). The patient antibodies colocalized with commercial antibodies to desmoplakins I and II, p0071, armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF), and myocardium-enriched zonula occludens-1-associated protein (MYZAP; Progen Biotechnik) (P <.01). CONCLUSION: One-third of the patients affected by El Bagre-EPF have rhythm abnormalities that slow the conduction of impulses in cardiac nodes and the cardiac conduction system. These abnormalities likely occur as a result of deposition of autoantibodies, complement, and other inflammatory molecules. We show for the first time that MYZAP is present in cardiac nodes.

Cell junction protein armadillo repeat gene deleted in velo-cardio-facial syndrome is expressed in the skin and colocalizes with autoantibodies of patients affected by a new variant of endemic pemphigus foliaceus in Colombia.

BACKGROUND: We previously described a new variant of endemic pemphigus foliaceus in El Bagre, Colombia, South America (El Bagre-EPF, or pemphigus Abreu-Manu). El Bagre-EPF differs from other types of EPF clinically, epidemiologically, immunologically and in its target antigens. We reported the presence of patient autoantibodies colocalizing with armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF), a catenin cell junction protein colocalizing with El Bagre-EPF autoantibodies in the heart and within pilosebaceous units along their neurovascular supply routes. Here we investigate the presence of ARVCF in skin and its possibility as a cutaneous El Bagre-EPF antigen. METHODS: We used a case-control study, testing sera of 45 patients and 45 controls via direct and indirect immunofluorescence (DIF/IIF), confocal microscopy, immunoelectron microscopy and immunoblotting for the presence of ARVCF and its relationship with El Bagre-EPF autoantibodies in the skin. We also immunoadsorbed samples with desmoglein 1 (Dsg1) ectodomain (El Bagre-EPF antigen) by incubating with the positive ARVCF samples from DIF and IIF. RESULTS: ARVCF was expressed in all the samples from the cases and controls. Immunoadsorption with Dsg1 on positive ARVCF immunofluorescence DIF/IIF cases showed that the immune response was present against non-desmoglein 1 antigen(s). Overall, 40/45 patients showed colocalization of their autoantibodies with ARVCF in the epidermis; no controls from the endemic area displayed colocalization. CONCLUSIONS: We demonstrate that ARVCF is expressed in many areas of human skin, and colocalizes with the majority of El Bagre-EPF autoantibodies as a putative antigen.

Pênfigo Foliáceo Endêmico (Fogo Selvagem) e sua associação com fatores ambientais e ocupacionais em Ouro Preto, Minas Gerais, Brasil / Endemic Pemphigus Foliaceus (Fogo Selvagem) and its association with environmental and occupational factors in Ouro Preto, Minas Gerais, Brazil

Resumo Pênfigo compreende grupo de doenças bolhosas autoimunes que possuem tendência à progressão, com evolução ilimitada e crônica e com prognóstico potencialmente fatal. O tipo mais comum é o Pênfigo Foliáceo Endêmico (PFE), caracterizado pela presença de lesões cutâneas com formação de bolhas na face, no couro cabeludo e na região interescapular. Fatores de ordem ambiental, genéticos e imunológicos podem desencadear a enfermidade. Entre os fatores ambientais, exposição a mercúrio, poeiras minerais e a picada do mosquito Simulium nigrimanum devem ser considerados. Buscou-se, neste artigo, relatar a ocorrência do PFE entre a população de Antônio Pereira, distrito rural de Ouro Preto, Minas Gerais, bem como identificar possíveis associações da doença com fatores ocupacionais e ambientais locais. Foi constatada uma prevalência de 4,57 casos de PFE/1.000 habitantes, considerada bastante elevada. Observou-se associação estatística entre a doença e contato com barragem de rejeitos de mineração (p = 0,048) e exposição ao mercúrio (p = 0,008). Os resultados indicam a necessidade de vigilância epidemiológica eficaz das comunidades afetadas, assim como adequada assistência à saúde dos pacientes acometidos pela doença.

Abstract Pemphigus comprises a group of autoimmune bullous diseases, which have a tendency of progression, with unlimited and chronic development and with a potentially to fatal disease prognosis. The most common type is the Endemic Pemphigus Foliaceus (EPF), characterized by the presence of skin lesions with blistering located on the face, scalp and interscapular region. Environmental, genetic and immunological factors may trigger the disease. Among the environmental factors, exposure to mercury, mineral dust and Simulium nigrimanum mosquitoes bite should be considered. Sought to, in this article, it is reported the occurrence of PFE among the population of Antonio Pereira, rural district of Ouro Preto, Minas Gerais, and identify their possible association with occupational and environmental local factors. A prevalence of 4.57 cases of EPF/1.000 inhabitants, considered high was found. There was association between the disease and contact with dam tailings mining (p=0.048); and exposure to mercury (p=0.008). The results indicate the need for effective surveillance of the affected communities, as well as adequate health care of patients affected by the disease.

Análise espacial da distribuição de pênfigo vulgar e foliáceo no âmbito de três bacias hidrográficas presentes no nordeste do Estado de São Paulo e a relação com fatores ambientais / Analysis of the spatial distribution of pemphigus vulgaris and pemphigus foliaceus under three watersheds present in the northeastern state of São Paulo and the relationship with environmental factors

Focos geográficos bem definidos de pênfigo prevalecem no mundo todo, inclusive no Brasil. Nas últimas décadas vem sendo estudada a possibilidade de fatores ambientais participarem do desencadeamento da doença. A região nordeste do Estado de São Paulo, onde localizam-se três Bacias Hidrográficas, apresenta prevalência de duas formas clínicas do pênfigo, pênfigo vulgar (PV) e pênfigo foliáceo endêmico (PFE) sendo uma importante área para o estudo da doença. Nesse estudo, foi utilizado um Sistema de Informação Geográfica (SIG) para descrever a distribuição espacial e o comportamento temporal de PV e PFE nessa região do Estado de São Paulo nas últimas cinco décadas e caracterizar o uso e ocupação do solo no município com maior número de ocorrências de pênfigo. Os pacientes foram identificados baseados nos prontuários médicos entre 1965 e 2014. Os mapas temáticos foram desenvolvidos com o software ArcGIS 10.2. Para representar a distribuição espacial do pênfigo, os mapas foram organizados em décadas de 1965 a 2014. Para o município com maior número de ocorrências de PV e PFE, o uso e ocupação do solo, de acordo com a hidrografia, a vegetação nativa, à área agrícola, o solo exposto e a área urbana, foi analisado em um raio de 2 km no entorno da residência dos pacientes no momento do surgimento dos sintomas. Como análise adicional, mapas ilustrando a distribuição dos casos de pênfigo de acordo com as classes hipsométricas, declividade do solo e densidade populacional por distrito do município (Norte, Sul, Leste, Oeste e Central) foram também desenvolvidos. Quatrocentos e vinte e seis casos foram analisados. Os casos de PFE predominaram, com 285 (67%) dos casos. De acordo com a distribuição espacial e evolução temporal, PV não foi reportado de 1965 a 1974, entretanto, os casos de PV tiveram um aumento contínuo nas próximas décadas e ultrapassou o número de casos de PFE na última década. Analisando de forma acumulada os casos, tanto o PV quanto o PFE tiveram aumento ao longo do período estudado, revelando uma expansão espacial. A Bacia Hidrográfica do Rio Pardo teve o maior número de casos com um total de 153 (41% PV e 59% PFE). No período de 1965 a 2014 o número de cidades com registros de casos de PV e PFE aumentou de 0 para 49 e de 13 para 60, respectivamente, com Ribeirão Preto e Batatais sendo os principais focos geográficos de PV e PFE, respectivamente. Ribeirão Preto foi o município com maior ocorrência de pênfigo (35 casos de PV e 37 casos de PFE). A área agrícola (42%) e o solo exposto (33,2%) foram os usos do solo que predominam no município. Além disso, todos os pacientes com PV ou PFE moram perto de rios e área agrícola. Em Ribeirão Preto, os casos de pênfigo estão concentrados nos distritos norte e oeste, os casos de PFE estão distribuídos em baixas altitudes quando comparadas com o PV e tanto o PV quanto o PFE predominam em áreas com baixa porcentagem de declividade do solo. No contexto da saúde pública, o SIG se tornou uma importante ferramenta que ajuda os pesquisadores entenderem a ocorrência e tendência de certos eventos, conduzindo nas melhores estratégias de controle de doenças. As análises de distribuição espacial e evolução temporal mostraram que os casos de PV e PFE aumentaram na região nordeste do Estado de São Paulo nas últimas cinco décadas. Esse monitoramento também ajudou a identificar os principais focos geográficos de pênfigo nessa região. A predominância de agricultura e solo exposto em Ribeirão Preto e a proximidade dos casos com rios e agricultura reforça a hipótese de que os fatores ambientais desempenham um importante papel na etiopatogênese do pênfigo

Defined foci of pemphigus prevalence worldwide, including Brazil, raise the possibility that environmental factors trigger the onset of this disease. The northeastern region of the state of São Paulo is located within three Watersheds and is an appropriate site to investigate pemphigus because this disease is prevalent in both clinical forms--endemic pemphigus foliaceus (PFE) and pemphigus vulgaris (PV)--therein. In this study, we have used Geographic Information Systems (GIS) to describe the spatial distribution and temporal behavior of PV and PFE in this region of the state of São Paulo over the last five decades; we have also characterized land use in the city with the highest number of cases. Patients were identified based on patients' medical records between 1965 and 2014. Thematic maps were developed with the ArcGIS 10.2 software. To represent the spatial distribution of pemphigus, maps were organized in decades from 1965 to 2014. For the city with the highest occurrence of PFE and PV cases, land use regarding hydrography, native vegetation, agriculture, exposed soil, and urbanization was analyzed within a 2-km buffer surrounding from the patients' residencies considering the address where the pemphigus clinical signs and symptoms started. For additional analysis, thematic maps illustrating the distribution of pemphigus cases according to hypsometric classes, soil declivity, and population density by sector (North, South, East, West, and Central) were designed. Four hundred and twenty-six cases were analyzed. PFE cases predominated: they corresponded to 285 or 67% of the cases. Regarding spatial distribution and temporal evolution, PV was not reported from 1965 to 1974; notwithstanding, PV rose in the following four decades and overcame the number of PFE cases in the last decade. Regarding cumulative cases, both PV and PFE increased throughout the studied period, which revealed spatial expansion. The Pardo River Basin had the highest number of cases with a total of 153 (41% PV and 59% PFE). In the studied period, the number of cities with recorded cases of PV and PFE increased from 0 to 49 and from 13 to 60, respectively, with Ribeirão Preto and Batatais being the main geographical foci of PV and PFE, respectively. Ribeirão Preto was the city with the highest occurrence of pemphigus--35 PV cases and 37 PFE cases. Agricultural area (42%) and exposed soil (33.2%) were the land uses that predominated in the city. In addition, all patients with PV and PFE lived close to rivers and agricultural areas. In Ribeirão Preto, pemphigus cases were concentrated in the northern and western sectors; PFE cases were distributed at lower altitudes as compared to PV; and both PV and PFE predominated in areas with lower percentage of declivity. In the context of public health, GIS has become a powerful tool that helps researchers to understand the occurrence and trend of some events, leading to improved interventional strategies and disease control. The spatial distribution and temporal evolution analyses showed PV and PFE increased in the northeastern region of the state of São Paulo over the last five decades. This monitoring also helped to identify the main geographical foci of pemphigus. The predominance of agriculture and exposed soil in Ribeirão Preto and the proximity of the cases to rivers and agriculture reinforced the hypothesis that environmental factors play a role in pemphigus etiopathogenesis

Aspectos etiológicos e epidemiológicos do pênfigo foliáceo endêmico (fogo selvagem) / Etiological and epidemiological aspects of pemphigus foliaceus (wild fire)

Introdução: Durante a primeira metade do século XX, o pênfigo foliáceo endêmico (fogo selvagem) teve importante impacto social, econômico e político no Brasil. Após mais de um século desde seus primeiros relatos essa doença ainda guarda interrogações sobre o envolvimento de fatores ambientais desencadeantes e sua característica autoimune e endêmica. O objetivo do trabalho é revisar trabalhos publicados por mais de um século, destacando os aspectos epidemiológicos da doença (das diferentes formas endêmicas pelo mundo) e avanços no estudo da sua etiologia. Material e Métodos: Utilizaram-se de trabalhos no PubMed, LILACS, CAPES, Google Acadêmico, Anais Brasileiros de Dermatologia. Resultados: O fogo selvagem sofreu grande redução do número de casos, principalmente a partir da década de 80 do século XX. O número de estudos sobre a doença vem diminuindo a cada década, várias informações sobre seus aspectos etiológicos e epidemiológicos permanecem há mais de um século sem comprovação precisa. Conclusões: Concluímos que o reduzido número de trabalhos atuais sobre o fogo selvagem se deve a redução considerável da sua incidência após mudanças ecológicas, avanços tecnológicos e melhoria das condições de vida da população das áreas endêmicas. As autoridades deveriam torná-la de notificação compulsória, facilitando a identificação de novos casos e de possíveis áreas endêmicas nos dias atuais. Mais estudos na área contribuiriam também ao estudo das doenças autoimunes em geral e dos fatores relacionados com o aumento da incidência de pênfigo vulgar em áreas endêmicas para fogo selvagem.

Ribosomal protein s6-ps240 is expressed in lesional skin from patients with autoimmune skin blistering diseases.

BACKGROUND: The in situ signaling transduction within skin biopsies from patients affected by autoimmune skin blistering diseases is not well-characterized. AIM: In autoimmune skin blistering diseases, autoantibodies seem to trigger several intracellular signaling pathways and we investigated the presence of the phosphorylated form of ribosomal protein S6-pS240 within autoimmune skin blistering diseases biopsies. MATERIALS AND METHODS: We utilized immunohistochemistry to evaluate the presence of S6-pS240 in lesional skin biopsies of patients affected by autoimmune skin blistering diseases including patients with an endemic and nonendemic pemphigus foliaceus (non EPF), with bullous pemphigoid (BP), pemphigus vulgaris (PV), dermatitis herpetiformis (DH), and the respective controls. RESULTS: Most autoimmune bullous skin diseases biopsies stained positive for S6-pS240 around lesional blisters, including adjacent areas of the epidermis; and within upper dermal inflammatory infiltrates, and/or mesenchymal-endothelial cell junctions within the dermis. CONCLUSIONS: We document that S6-pS240 is expressed in lesional areas of skin biopsies from patients with autoimmune skin blistering diseases, as well as on eccrine glands and piloerector muscles. Thus, the role of this molecule in autoimmune skin blistering diseases warrants further study.

Both qualitative and quantitative genetic variation of MHC class II molecules may influence susceptibility to autoimmune diseases: the case of endemic pemphigus foliaceus.

The MHC class II transactivator (CIITA) is a key regulator in expression of the HLA class II genes. It is well known that HLA-DRB1 genotypes have a strong influence on the risk of multifactorial autoimmune diseases, but the effect of CIITA genotypes remains controversial. We tested in a case-control study whether CIITA polymorphisms influence the risk of developing endemic pemphigus foliaceus (EPF) and whether CIITA and HLA-DRB1 interact as regards susceptibility to the disease. The rs4774 SNP is not associated to EPF, while rs3087456 in the CIITA gene promoter is associated with susceptibility [odds ratio (OR) = 2.6, p < 0.001 and OR = 2.0 p = 0.003 for genotypes G/G and G/A, respectively]. We suggest that the associations result from the effect of genetically controlled levels of CIITA on expression of the susceptible and protective HLA class II molecules. Remarkably, the interaction between CIITA and HLA-DRB1 genotypes is strong and additive. The OR for individuals having two susceptible HLA-DRB1 alleles is 14.1 in presence of the susceptible CIITA G/G or G/A genotypes and much lower (2.2) in presence of the protective CIITA A/A genotype. We conclude that quantitative as well as qualitative variation of HLA class II molecules have an effect on the risk of an individual developing EPF.

Endemic pemphigus foliaceus over a century: Part I.

BACKGROUND: Endemic pemphigus foliaceus (EPF) is the only known autoimmune disease presenting in circumscribed geographic areas. AIM: We aim to provide information concerning the natural course of EPF, including systemic compromise in the presteroid era, which has been largely unavailable in the current medical literature. MATERIAL #ENTITYSTARTX00026; METHODS: By a retrospective review of the literature we aim to compile and compare the focus of EPF and the current knowledge about them. The main aim of this review is to summarize our current knowledge of EPF, including data described almost one century ago; and, to include several unindexed reports, which may have not been available to many current scientists and health care personnel. RESULTS: Foci of EPF have been described in several Central American and South American countries, affecting predominately young people and Amerindians, with an additional female predilection. Although most cases have occurred in Brazil, some cases have been reported in Peru, Paraguay, El Salvador, and Venezuela. Another variant of EPF has been described in El Bagre, Colombia, affecting older men and a few post-menopausal females. Finally, another type of EPF was described in nomadic tribes affecting females of child bearing age in Tunisia, Africa. CONCLUSION: Our understanding of EPF has been hampered by a lack of government attention to these diseases, especially in some South and Central American countries. Other factors that have made past studies of EPF difficult include 1) that the disease foci are often located in rural areas bordering the rain forest of underdeveloped countries; and 2) military conflicts in some of these areas.

Endemic pemphigus over a century: Part II.

BACKGROUND: Endemic pemphigus foliaceus (EPF) is an autoimmune disease, classically occurring in a restricted geographic area. Foci of EPF have been described in several Central and South American countries, often affecting young people and Amerindians, with some female predilection. Although most American EPF cases have been documented in Brazil, cases have been reported in Peru, Paraguay, El Salvador and Venezuela. An additional variant of EPF has been described in El Bagre, Colombia, (El Bagre-EPF) affecting older men and a few post-menopausal females. Finally, one additional type of EPF has been described in nomadic tribes affecting females of child bearing age in Tunisia, Africa. AIMS: The main aim of this review is to summarize current knowledge about autoantigens, and immunologic and genetic studies in EPF. MATERIAL AND METHODS: We utilized a retrospective review of the literature, aiming to compile and compare the multiple geographic foci of EPF. RESULTS: The primary autoantigens in EPF are still considered to be desmogleins in the case of the Tunisian and all American cases, in contradistinction to plakins and desmogleins in El Bagre-EPF. Although several autoantigens are been suggested, their biochemical nature needs further elucidation. Current knowledge still supports the concept that an antibody mediated immune response represents the principal pathophysiology in all variants of EPF. CONCLUSION: A strong genetic susceptibility appears to contribute to disease development in several people affected by these diseases; however, no specific genes have been confirmed at present. We conclude that further investigation is necessary to define these disorders immunologically and genetically.

Pénfigo foliáceo endémico en tres regiones de la amazonía peruana: enero-diciembre 2004 / Endemic Pemphigus foliaceus in three regions of Peruvian Amazonia: January-December 2004

OBJETIVO: Determinar las características epidemiológicas y clínicas del pénfigo foliáceo endémico(PFE) en tres regiones de la Amazonía Peruana durante el año 2004. MATERIAL Y MÉTODOS: Estudio descriptivo, prospectivo y observacional realizado en tres regiones de la amazonía peruana. Los pacientes con PFE fueron captados en el Hospital de Apoyo de Chachapoyas (Amazonas), Hospital Hermilio Valdizán Medrano (Huánuco), Posta Médica EsSalud Santa Lucía-Uchiza (San Martín), en los centros de salud de cada departamento y mediante búsqueda activa durante Enero y Diciembre del año 2004. El diagnóstico se realizó en base a los criterios epidemiológico, clínico, histopatológico e inmunológico. RESULTADOS: Se captó un total de 10 casos de PFE en los departamentos de Amazonas, Huánuco y San Martín. Se determinó áreas endémicas de PFE en Tingo María, Tournavista y La Unión (Huánuco), Moyobamba (San Martín), Tuemal y Bagua (Amazonas). La mayor frecuencia de pacientes fueron de sexo masculino, menores de 40 años, de forma clínica generalizada con régimen de tratamiento irregular. Se detectó casos en Moyobamba y Tuemal a una altitud de 886 y 1172 msnm respectivamente, con características clínicas similares a la de los casos detectados a altitudes inferiores a 800 msnm. CONCLUSIÓN: De las regiones estudiadas, Huánuco es la que presenta mayor frecuencia de pacientes con PFE mientras que en San Martín y Amazonas la frecuencia es marcadamente inferior. Existen casos de PFE en San Martín y Amazonas a altitudes superiores a los 800 msnm.

OBJECTIVE: To determine clinical and epidemiological characteristics of Endemic Pemphigus Foliaceus (EPF) in three regions of Peruvian Amazon during 2004. MATERIAL AND METHODS: Descriptive, prospective and observational study realized in three regions of Peruvian Amazonia. Patients with EPF were enrolled in Chachapoyas Hospital (Amazonas), Hermilio Valdizan Medrano Hospital (Huanuco), Santa Lucia-Uchiza Essalud Health Station (San Martin), in Health Centers of each department and through active search during January and December of 2004. The diagnosis was realized based to clinical epidemiologic, histopathologic and immunologic features. RESULTS: It was enrolled a total of 10 cases with EPF in departments of Amazonas, Huanuco and San Martin. It was determined endemic areas of EPF in Tingo Maria, Tournavista and La Union (Huanuco), Moyobamba (San Martin), Tuemal and Bagua (Amazonas). The major frequency of patients was male, under of 40 years, generalized clinical form with regimen of irregular treatment. It was detected cases in Moyobamba and Tuemal at a height of 886 and 1172 masl respectively, with clinical characteristics similar to the cases detected at heights under 800 masl. CONCLUSION: Huanuco is area which present major frequency of patients with EPF, while in San Martin and Amazonas, the frequency is extremely lower. There are cases of EPF in San Martin and Amazonas at heights above 800 masl.

A new variant of endemic pemphigus foliaceus in El-Bagre, Colombia: the Hardy-Weinberg-Castle law and linked short tandem repeats.

BACKGROUND: We reported a new variant of endemic pemphigus foliaceus in El Bagre, Colombia. AIMS: Our study performed Complex Segregation Analysis (CSA) and short tandem repeats to discriminate between environmental and/or genetic factors in this disorder. MATERIALS AND METHODS: The CSA analysis was carried out according to the unified model, implemented using the transmission probabilities implemented in the computer program POINTER, and evaluated by using a software package for population genetic data analysis (GDA), Arlequin. We performed pedigree analyses by using Cyrillic 2.1 software, with a total of 30 families with 50 probands (47 males and 3 females) tested. In parallel to the CSA, we tested for the presence of short tandem repeats from HLA class II, DQ alpha 1, involving the gene locus D6S291 by using the Hardy-Weinberg- Castle law. RESULTS: Our results indicate that the best model of inheritance in this disease is a mixed model, with multifactorial effects within a recessive genotype. Two types of possible segregation patterns were found; one with strong recessive penetrance in families whose phenotype is more Amerindian-like, and another of possible somatic mutations. CONCLUSION: The penetrance of 10% or less in female patients 60 years of age or older indicates that hormones could protect younger females. The greatest risk factor for men being affected by the disorder was the NN genotype. These findings are only possible due to somatic mutations, and/or strong environmental effects. We also found a protective role for two genetic loci (D6S1019 AND D6S439) in the control group.

Inmunopatología de sujetos sanos de un área endémica para pénfigo foliáceo en Perú: Estudio comparativo con familiares / Immunopathologic characterization of healthy subjects in an endemic area for pemphigus foliaceus: Comparative study with relatives.

Introducción: el pénfigo foliáceo endémico (PFE) ha sido descrito a principios de los años 50 en la selva peruana. En el 2006, Ortega y col. reportaron la presencia de anticuerpos anti-desmogleina 1 en Pueblo Libre, Ucayali. Sin embargo, no existen reportes inmunológicos sobre los familiares de pacientes con PFE en la zona. Objetivos: comparar las características inmunopatológicas de los sujetos sanos de Pueblo Libre (Campo Verde-Ucayali) endémico para pénfigo foliáceo, con familiares sanos de pacientes con PFE y controles sanos de áreas no endémicas. Material y métodos: estudio prospectivo y multicéntrico realizado de junio a agosto del 2006 que incluyó a 41 sujetos sanos de la comunidad de Pueblo Libre, 11 familiares de pacientes con PFE y 20 sujetos sanos de áreas no endémicas de la enfermedad de los que se obtuvo muestras de sangre para la realización del estudio inmunopatológico (ELISA para anticuerpos anti desmogleína 1 y anti desmogleína 3) comparándose las características de cada grupo de investigación. Para fijar los valores de corte se realizó la estandarización del ELISA usando el análisis de características operativas del receptor (ROC). Resultados: en Pueblo Libre se encontró una prevalencia de anticuerpos anti desmogleína 1 de 46,3%. El patrón predominante fue el IgG2 (62,5%) y el IgG1 (56,3%). En el 31,7% se detectó anticuerpos anti-desmogleína 3. Existió alta correlación entre los valores índice de anticuerpos anti desmogleína 1 y anti desmogleína 3 (r=0,76), significativa a un nivel α=0,01. Para los familiares de los pacientes con PFE, el 45,5% fueron positivos para anticuerpos anti-desmogleνna 1 con un patrσn predominante IgG1 (63,6%) e IgG2 (54,5%). Se detectó anticuerpos anti-desmogleína 1 en el 10 % de sujetos sanos de áreas no endémicas; no se detectó anticuerpos anti desmogleína 3 en este grupo. Conclusiones: las personas sanas expuestas a factores ambientales de los focos endémicos de PFE y los familiares de pacientes desarrollan anticuerpos no patogénicos anti desmogleína 1 y 3 con características inmunopatológicas similares.

Introduction: endemic pemphigus foliaceus (PFE) has been described at the beginning of the 50s in the peruvian forest. In 2006,Ortega & col. reported the presence of desmoglein 1 antibodies in Pueblo Libre, Ucayali. Nevertheless, immune reports does not exist on patients’ relatives with PFE in the zone. Objetives: to compare the immunopathologic profiles of healthy subjects from Pueblo Libre (an area in Ucayali, endemic for pemphigus foliaceus), with healthy relatives of patients with endemic pemphigus foliaceus (EPF) and healthy controls from non-endemic areas. Materials and methods: this is a prospective multicentric study performed from June to August 2006. The sample consisted of 41 healthy subjects from the Pueblo Libre community, 11 relatives of EPF patients and 20 healthy subjects from non-endemic areas. Blood samples were obtained for immunopathologic studies (ELISA technique for antibodies against desmoglein-1 and desmoglein- 3). The immunopathologic profiles of each group were compared. Standardization of ELISA was performed using the analysis of receptor operative characteristics (ROC) to find appropriate cut-off values. Results: in Pueblo Libre, the prevalence of antibodies against desmoglein-1 was 46,3%. The predominant pattern was 56,3% for IgG1 and 62,5% for IgG2. Antibodies against desmoglein-3 were found in 31,7% of the sample. A high correlation was found between the index values of antibodies against desmoglein-1 and desmoglein-3. (r=0.76); this is statistically significant, with an alpha = 0,001. The frequency of antibodies against desmoglein-1 was 45,5% in the relatives of EPF patients; the predominant pattern was 63,6% for IgG1 and 54,5% for IgG2. Antibodies against desmoglein-1 were detected in two healthy subjects from non-endemic areas; antibodies against desmoglein-3 were not detected. Conclusion: healthy subjects who are exposed to environmental factors in a focus of endemic pemphigus foliaceus and the relatives of patients with EPF develop non-pathogenic antibodies against desmoglein-1 and -3 with similar immunologic profiles.