Neurological disorders in patients with bullous pemphigoid: clinical and experimental investigations

Pemphigus and pemphigoid are associated with Alzheimer's disease in older adults: evidence from the US Nationwide inpatient sample 2016-2018

BACKGROUND

Pemphigus and pemphigoid are rare autoimmune skin disorders caused by autoantibodies against structural proteins and characterized by blistering of the skin and/or mucous membranes. Associations have been noted between skin diseases and Alzheimer's dementia (AD). Dementia is a neurological disorder of progressive cognitive impairment with increasing incidence among older adults. This study aimed to assess the potential associations between pemphigus, pemphigoid and AD in a large, nationally representative US cohort.

METHODS

All data of hospitalized patients aged 60 years or older were extracted from the US Nationwide Inpatient Sample (NIS) database 2016-2018. Patients with a history of head trauma, diagnosis of vascular dementia, history of cerebrovascular disease, or malformation of cerebral vessels were excluded. The study population was divided into those with and without pemphigus (cohort 1) and with and without pemphigoid (cohort 2).

RESULTS

Pemphigus was independently associated with a 69% increased risk of AD. Adults ≥80 years old with pemphigus were 72% more likely to develop AD than adults without pemphigus. Women with pemphigus were 78% more likely to develop AD than women without pemphigus. On the other hand, pemphigoid was independently associated with a 39% increased risk for AD and subjects ≥80 years with pemphigoid were 40% more likely to have AD than those without pemphigoid. Females with pemphigoid were 63% more likely to have AD than those without pemphigoid. Moreover, Hispanic older adults with pemphigus were 3-times more likely to have AD than those without pemphigoid.

CONCLUSIONS

Pemphigus and pemphigoid were both independently associated with AD in older adults, especially among females and octogenarians. Further studies addressing the etiology and mechanisms underlying these associations are highly warranted.

Skin Eosinophil Counts in Bullous Pemphigoid as a Prognostic Factor for Disease Severity and Treatment Response

Dermal infiltration of eosinophils and eosinophilic spongiosis are prominent features of bullous pemphigoid lesions. Although several observations support the pathogenic role of eosinophils in bullous pemphigoid, few studies have examined the impact of skin eosinophil counts on disease severity and treatment response. This retrospective study assessed the association between eosinophil counts in skin biopsy samples of 137 patients with bullous pemphigoid and their demographic characteristics, comorbidities, disease severity, and treatment response. There was no relationship between eosinophil count and age, sex, or disease severity at disease onset. There was a positive relationship between eosinophil counts and neurological comorbidity and a negative relationship between eosinophil counts and treatment response. At all follow-up points patients with no tissue eosinophils had a better response to treatment than patients with any tissue eosinophil count. In conclusion, skin eosinophil counts in patients with bullous pemphigoid are not correlated with disease severity at onset, but can serve as a negative prognostic marker for treatment response.

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

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

Epidemiology and comorbidities in bullous pemphigoid in the period from January of 2019 to the January of 2021

Introduction: Bullous pemphigoid is an autoimmune bullous dermatosis that most commonly occurs in elderly patients. Due to its pathogenesis and treatment of the disease, it can also affect the development of comorbidities. Aim: Determination of comorbidities and their frequency in patients with bullous pemphigoid, as well as their distribution by sex and the estimation of the duration of dermatosis from the onset of symptoms to data collection. Material and methods: In the period from January 2019 to January 2021, a number of 80 patients was analyzed. Basic patient data (age, sex, time of illness) and data on accompanying comorbidities were obtained. Data were categorized based on the ICD-10 classification into groups of diseases, as well as individual diseases that occurred frequently in the population. Results: Of the total number of respondents, 41.3% were male and 58.8% female. The average age of the respondents was 75.8 years, 76.45 years for men and 75.36 years for women. The period from the onset of symptoms to data collection was 3 months, while the average age of the disease in all subjects was 74.4 years. The most common comorbidities were hypertension 73.75%, psychiatric diseases 25%, type 2 diabetes mellitus 25%, other skin diseases 21.25%, urinary tract disorders 18.75%, ischemic heart disease 12.5%, type 1 diabetes mellitus 10%, kidney disease 8.75%, neurological disease 6.25%. Comorbidities were statistically more common in female patients: hypertension, ischemic heart disease, skin diseases and type 2 diabetes mellitus. Conclusion: In our study, bullous pemphigoid is confirmed the disease is of the elderly, predominantly female. Female patients suffer from some comorbidities more often. The period from the onset of symptoms to the collection of data is about 3 months. It is also showed that there are a number of comorbidities in the studied pemphigoid population, however, a large number of studies are needed to determine their association.

Bullous pemphigoid: An immune disorder related to aging (Review)

Bullous pemphigoid (BP) is the most frequent subepidermal autoimmune blistering disease and is caused by autoantibodies directed against two principal antigens of the hemidesmosome, BP antigen 180 and BP antigen 230. The pathogenesis of BP is dependent upon the interaction between genetic predisposition, physiological skin alterations due to aging and specific triggers. Several triggers have already been reported to induce this disease and include drugs, thermal or electrical burns, surgical procedures, trauma, UV radiation, radiotherapy, chemicals and infections. Data from the current literature support the hypothesis that alterations of the skin barrier associated with aging increase individual susceptibility to these aforementioned triggers. Consequently, this has been reported to lead to the attack of autoantibodies, demonstrating the predilection of BP for the elderly population. The identification of triggering factors and comorbidities may aid in understanding the pathogenesis of BP and improve clinical management by encouraging their prompt recognition and removal. Moreover, the present review has indicated that current management of BP should be aimed at counteracting the detrimental effects of aging on the skin by restoring skin barrier integrity and maintaining cutaneous homeostasis, for example with systematic applications of topical emollients and photoprotection. This strategy could prove even more beneficial in the elderly, in which frequent comorbidities associated with age often narrow available immunosuppressive treatment options. Furthermore, the safety of treatment regimens may significantly affect outcome and prognosis.

The burden of neurological comorbidities in six autoimmune bullous diseases: a population-based study

BACKGROUND

Apart from bullous pemphigoid (BP), the association of other autoimmune bullous diseases (AIBDs) with neurological conditions is poorly understood.

OBJECTIVE

To estimate the association between a wide array of AIBDs and neurological conditions.

METHODS

A retrospective cross-sectional study recruited patients with BP, mucous membrane pemphigoid (MMP), epidermolysis bullosa acquisita (EBA), pemphigoid gestationis (PG), pemphigus vulgaris (PV) and pemphigus foliaceus (PF). These patients were compared with their age- and sex-matched control subjects with regard to the lifetime prevalence of Parkinson's disease (PD), Alzheimer's disease (AD), stroke, epilepsy and multiple sclerosis (MS). Logistic regression was used to calculate OR for specified neurological disorders.

RESULTS

The current study included 1743, 251, 106, 126, 860 and 103 patients diagnosed with BP, MMP, EBA, PG, PV and PF, respectively. These patients were compared with 10 141, 1386, 606, 933, 5142 and 588 matched controls, respectively. Out of the investigated neurological conditions, PD associated with BP (OR, 2.71; 95% CI, 2.19-3.35); AD with BP (OR, 2.11; 95% CI, 1.73-2.57), MMP (OR, 2.37; 95% CI, 1.03-5.47), EBA (OR, 6.00; 95% CI, 1.90-18.97) and PV (OR, 2.24; 95% CI, 1.40-3.60); stroke with BP (OR, 1.84; 95% CI, 1.55-2.19) and EBA (OR, 2.79; 95% CI, 1.11-7.01); and epilepsy with BP (OR, 2.18; 95% CI, 1.72-2.77) and PV (OR, 1.80; 95% CI, 1.19-2.73). MS did not significantly cluster with any of the six AIBDs.

CONCLUSION

In addition to BP, EBA and PV were found to cluster with neurological comorbidities. Patients with these AIBDs with compatible symptoms may be carefully assessed for comorbid neurological disorders.

Coexistence of bullous pemphigoid with neuropsychiatric comorbidities is associated with anti-BP230 seropositivity

BACKGROUND

While clustering of bullous pemphigoid (BP) with neuropsychiatric diseases is well-established, the clinical and immunological profile of BP patients with this comorbidity remains to be decisively determined.

OBJECTIVES

To evaluate the burden of neurological and psychiatric comorbidities among patients with BP and to elucidate the clinical, immunological and immunopathological features of patients with BP and comorbid neuropsychiatric conditions.

METHODS

We performed a retrospective study encompassing patients diagnosed with BP throughout the years 2009-2020 in a specialized tertiary referral centre. Multivariate logistic regression model was used to identify predictors of neuropsychiatric conditions among patients with BP.

RESULTS

The study included 273 patients with BP, of whom 123 (45.1%) presented with comorbid neuropsychiatric disease. Compared to the remaining patients with BP (n = 150), those with pre-existing neuropsychiatric diseases demonstrated older mean [standard deviation (SD)] age [81.7 (9.1) vs. 76.9 (10.1); P < 0.001], female preponderance (65.0% vs. 49.3%; P = 0.009), higher seropositivity rate of anti-BP230 (67.7% vs. 36.5%; P = 0.006) and higher levels of anti-BP180 NC16A IgG [651.3 (1279.6) vs. 370.4 (818.6) U/mL; P = 0.039]. In multivariate analysis, anti-BP230 seropositivity was independently associated with coexistence of BP with neuropsychiatric conditions [adjusted odds ratio (OR), 3.43; 95% CI, 1.24-9.52; P = 0.018]. In a sensitivity analysis confined to patients with neurological diseases (n = 103), older age [82.1 (8.4) vs. 77.2 (10.3); P < 0.001] and increased anti-BP230 seropositivity (68.0% vs. 39.7%; P = 0.018) were identified.

CONCLUSIONS

The coexistence of BP with neuropsychiatric diseases is independently associated with the generation of anti-BP230 antibodies.

Tissue eosinophil levels as a marker of disease severity in bullous pemphigoid

BACKGROUND

Eosinophils play an important role in bullous pemphigoid (BP) pathogenesis. Although tissue infiltration with eosinophils has been known for a long time, there is a lack of knowledge about the relationship between tissue eosinophil levels and disease severity and clinical characteristics of the patients.

METHODS

Fifty-nine patients diagnosed with BP between January 2008 and December 2018 were reviewed. Haematoxylin-Eosin (H&E)-stained preparations were re-evaluated in terms of tissue eosinophil levels. For disease severity, Bullous Pemphigoid Disease Area Index (BPDAI) was used. The relationship between tissue eosinophil levels and disease severity and clinical features were evaluated.

RESULTS

Erosion/blister and urticaria/erythema BPDAI scores were higher in the group with high tissue eosinophil level than the group with low tissue eosinophil level. Tissue and peripheral blood eosinophil count were correlated with total urticaria/erythema BPDAI scores. There was no correlation between blood and tissue eosinophil count. The mortality rate was 64.7% vs 44.0% in the high vs low tissue eosinophil groups. Tissue eosinophil levels were high in patients with BP accompanying neurological disease.

CONCLUSIONS

Tissue eosinophil count and peripheral blood eosinophil count were correlated with disease severity in BP. Tissue eosinophil levels were also high in patients with BP accompanying neurological disease.

Detection of underlying dementia in bullous pemphigoid patients using cognitive evaluation tests: a multicenter case-control study

Background

Preliminary observation in clinical practice showed that subjective neurocognitive complaints are relatively common in bullous pemphigoid (BP) patients. Yet, little has been done to investigate the neurocognitive status in BP.

Methods

This is a multicenter observational case-control study comprised of 61 BP patients and 65 matched control subjects from 3 medical centers in China from 2014 to 2019. To evaluate the cognitive function between BP patients and matched controls, all the subjects finished the mini-mental state examination (MMSE) and montreal cognitive assessment (MoCA).

Results

The overall scores were significantly lower in BP than in controls (P_MoCA<0.001). The percentage of patients screened positive for cognitive impairment in the BP group was significantly higher than in the control group (P_MMSE<0.001, P_MoCA<0.001). On multivariate analysis, BP was associated with increased odds of cognitive impairment by MMSE and MoCA (P_MMSE=0.017, P_MoCA=0.007).

Conclusions

BP patients had decreased cognitive abilities and were at a higher risk of cognitive impairment. The evaluation of cognitive impairment may be warranted for BP patients in clinical practice for early diagnosis and therapy of dementia.

Parkinson's disease and skin

Parkinson's disease is associated with a variety of dermatologic disorders and the study of skin may provide insights into pathophysiological mechanisms underlying this common neurodegenerative disorder. Skin disorders in patients with Parkinson's disease can be divided into two major groups: 1) non-iatrogenic disorders, including melanoma, seborrheic dermatitis, sweating disorders, bullous pemphigoid, and rosacea, and 2) iatrogenic disorders related either to systemic side effects of antiparkinsonian medications or to the delivery system of antiparkinsonian therapy, including primarily carbidopa/levodopa, rotigotine and other dopamine agonists, amantadine, catechol-O-methyl transferase inhibitors, subcutaneous apomorphine, levodopa/carbidopa intestinal gel, and deep brain stimulation. Recent advances in our understanding of the role of α-synuclein in peripheral tissues, including the skin, and research based on induced pluripotent stem cells derived from skin fibroblasts have made skin an important target for the study of Parkinson's disease pathogenesis, drug discovery, novel stem cell therapies, and diagnostics.

A Monocentric Retrospective Observational Study of Comorbidities in Patients Affected by Autoimmune Bullous Diseases

BACKGROUND/AIM

Autoimmune bullous diseases (AIBDs) of the skin and mucosae include a heterogeneous group of chronic diseases, which could be associated with various comorbidities. The purpose of this study was to evaluate the comorbidity profiles of patients affected by AIBDs, who referred to the Dermatological Clinic of Padua from December 2015 to June 2018.

PATIENTS AND METHODS

A monocentric retrospective observational study was conducted on 157 patients with diagnosis of AIBDs. Patients' comorbidities were investigated during the periodic visits of follow-up and through the analysis of computerized medical records.

RESULTS

Among the 157 patients, 40 (25.5%) were diagnosed with PV, 15 (9.6%) with PF, and 102 (64.9%) with BP. Nine different comorbidities were observed, but only two of these were statistically significantly associated with BP: type 2 diabetes (p=0.0142) and neuropsychiatric disorders (p=0.015).

CONCLUSION

BP is statistically significantly associated with type 2 diabetes mellitus and neuropsychiatric diseases. The correlation with neuropsychiatric pathologies is interesting for the possible bidirectional role in their etiology. The association with type 2 diabetes mellitus could suggest more caution in the administration of systemic corticosteroids, especially in elderly patients.

Association Between Pemphigus and Neurologic Diseases

Importance

The association between pemphigus and neurologic diseases was not evaluated systematically in the past. In a recent uncontrolled cross-sectional study, Parkinson disease was found to be significantly associated with pemphigus; in the same study, epilepsy had a nonsignificant association with pemphigus. Several case reports have suggested that pemphigus coexists with multiple sclerosis and dementia.

Objective

To estimate the association between pemphigus and 4 neurologic conditions (dementia, epilepsy, Parkinson disease, and multiple sclerosis), using one of the largest cohorts of patients with pemphigus.

Design, Setting, and Participants

A retrospective population-based cross-sectional study was performed between January 1, 2004, and December 31, 2014, using the database of Clalit Health Services, the largest public health care organization in Israel, in the setting of general community clinics, primary care and referral centers, and ambulatory and hospitalized care. A total of 1985 patients with a new diagnosis of pemphigus and 9874 controls were included in the study.

Main Outcomes and Measures

The proportion of dementia, epilepsy, Parkinson disease, and multiple sclerosis was compared between patients diagnosed with pemphigus and age-, sex-, and ethnicity-matched control participants. Logistic regression was used to calculate odds ratios (ORs) for dementia, epilepsy, Parkinson disease, and multiple sclerosis. The association was examined after a sensitivity analysis that included only patients treated with long-term, pemphigus-specific medications (corticosteroids, immunosuppressants, or rituximab) and after adjustment for several confounding factors.

Results

When comparing the 1985 cases (1188 women and 797 men; mean [SD] age, 72.1 [18.5] years) with the 9874 controls (5912 women and 3962 men; mean [SD] age, 72.1 [18.5] years), dementia was seen in 622 cases (31.3%) vs 1856 controls (18.8%), with an OR of 1.97 (95% CI, 1.77-2.20). Epilepsy was present in 74 cases (3.7%) vs 210 controls (2.1%), with an OR of 1.78 (95% CI, 1.36-2.33). Parkinson disease was seen in 175 cases (8.8%) vs 437 controls (4.4%), with an OR of 2.09 (95% CI, 1.74-2.51). Multiple sclerosis was present in 2 cases (0.1%) vs 6 controls (0.01%), with an OR of 1.65 (95% CI, 0.34-8.22). Study findings were robust to sensitivity analysis that included patients receiving pemphigus-specific treatments. Estimates were not altered significantly after controlling for comorbidities and overuse of health care.

Conclusions and Relevance

An association was observed between pemphigus and specific neurologic diseases, including dementia, Parkinson disease, and epilepsy. Physicians treating patients with pemphigus should be aware of this possible association. Patients with pemphigus should be carefully assessed for comorbid neurologic disorders and receive appropriate treatment.

Skin Barrier and Autoimmunity-Mechanisms and Novel Therapeutic Approaches for Autoimmune Blistering Diseases of the Skin

One of the most important functions of the skin besides regulating internal body temperature includes formation of the barrier between the organism and the external environment, hence protecting against pathogen invasion, chemical and physical assaults and unregulated loss of water and solutes. Disruption of the protective barrier is observed clinically in blisters and erosions of the skin that form in autoimmune blistering diseases where the body produces autoantibodies against structural proteins of the epidermis or the epidermal-dermal junction. Although there is no cure for autoimmune skin blistering diseases, immune suppressive therapies currently available offer opportunities for disease management. In cases where no treatment is sought, these disorders can lead to life threatening complications and current research efforts have focused on developing therapies that target autoantibodies which contribute to disease symptoms. This review will outline the involvement of the skin barrier in main skin-specific autoimmune blistering diseases by describing the mechanisms underpinning skin autoimmunity and review current progress in development of novel therapeutic approaches targeting the underlying causes of autoimmune skin blistering diseases.

Subepidermal autoimmune bullous diseases: overview, epidemiology, and associations

Subepidermal autoimmune bullous diseases of the skin and mucosae comprise a large group of chronic diseases, including bullous pemphigoid, pemphigoid gestationis, mucous membrane pemphigoid, linear IgA bullous dermatosis, epidermolysis bullosa acquisita, and anti-p200 pemphigoid. These diseases are characterized by an antibody response toward structural components of the basement membrane zone, resulting in subepidermal blistering. The epidemiological features of these diseases vary substantially in different regions of the world. Observational studies investigating comorbidities and associations among patients with these diseases are inconsistent and sometimes inconclusive. This review provides a brief overview regarding each one of the subepidermal autoimmune bullous diseases. In addition, it summarizes the most recent understanding of the epidemiological features and associations of this group of organ-specific autoimmune diseases.

Complement-Activating Capacity of Autoantibodies Correlates With Disease Activity in Bullous Pemphigoid Patients

Background: Bullous pemphigoid is a subepidermal blistering skin disease, associated with autoantibodies to hemidesmosomal proteins, complement activation at the dermal-epidermal junction, and dermal granulocyte infiltration. Clinical and experimental laboratory findings support conflicting hypotheses regarding the role of complement activation for the skin blistering induced by pemphigoid autoantibodies. In-depth studies on the pathogenic relevance of autoimmune complement activation in patients are largely lacking. Therefore, the aim of this study was to investigate the pathogenic relevance of complement activation in patients with bullous pemphigoid. Complement activation by autoantibodies in vivo as measured by the intensity of complement C3 deposits in the patients' skin and ex vivo by the complement-fixation assay in serum was correlated with the clinical disease activity, evaluated by Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and Bullous Pemphigoid Disease Area Index (BPDAI), as well as, with further immunopathological findings in patients with bullous pemphigoid. Results: Complement-activation capacity of autoantibodies ex vivo, but not deposition of complement in the perilesional skin of patients, correlates with the extent of skin disease (measured by ABSIS and BPDAI) and with levels of autoantibodies. Conclusions: Our study provides for the first time evidence in patients for a pathogenic role of complement activation in bullous pemphigoid and should greatly facilitate the development of novel diagnostic tools and of more specific therapies for complement-dependent autoimmune injury.

Comorbidities and Treatment Strategies in Bullous Pemphigoid: An Appraisal of the Existing Litterature

Bullous Pemphigoid is an autoimmune skin blistering disease. It is caused by deposition of auto antibodies along the dermal-epidermal border leading to inflammation. The antibodies are directed against anchoring filaments in the epidermis, but these antigens are also present in the neurological tissues and this has led to speculation of an association between multiple sclerosis and bullous pemphigoid. Additionally recent epidemiological studies have pointed at an increased risk of cardio-vascualr diseases and an increased moratality among the patients with bullous pemphigoid. In this mini review we present the recent findings in this area and as well as the treatment strategies when comorbidities are taken into consideration.

The Growing Incidence of Bullous Pemphigoid: Overview and Potential Explanations

Bullous pemphigoid (BP) is the most common type of subepidermal autoimmune bullous diseases. BP characteristically affects the elderly and is seen mainly in patients older than 70 years. While the annual incidence of BP has been estimated to be between 2.4 and 23 cases per million in the general population, it rises exponentially to 190-312 cases per million in individuals older than 80 years. In addition, a growing body of evidence reports a remarkable trend of increased incidence of BP, showing a 1.9- to 4.3-fold rise over the past two decades. This demonstrable increase warrants a higher awareness of the increased risk to develop BP. This review summarizes the current understanding of the epidemiological features of BP and sheds light on the putative explanations for its growing incidence.

Autoimmune Subepidermal Bullous Diseases of the Skin and Mucosae: Clinical Features, Diagnosis, and Management

Autoimmune subepidermal blistering diseases of the skin and mucosae constitute a large group of sometimes devastating diseases, encompassing bullous pemphigoid, gestational pemphigoid, mucous membrane pemphigoid, epidermolysis bullosa acquisita, and anti-p200 pemphigoid. Their clinical presentation is polymorphic. These autoimmune blistering diseases are associated with autoantibodies that target distinct components of the basement membrane zone of stratified epithelia. These autoantigens represent structural proteins important for maintenance of dermo-epidermal integrity. Bullous pemphigoid (BP) is the most common subepidermal autoimmune blistering disease of the skin and mucosae. Although the disease typically presents with a generalized blistering eruption associated with itch, atypical variants with either localized bullous lesions or "non-bullous" presentations are observed in approximately 20% of patients. A peculiar form of BP typically associated with pregnancy is pemphigoid gestationis. In anti-p200 pemphigoid, patients present with tense blisters on erythematosus or normal skin resembling BP, with a predilection for acral surfaces. These patients have antibodies targeting the 200-kDa basement membrane protein. Epidermolysis bullosa is a rare autoimmune blistering disease associated with autoantibodies against type VII collagen that can have several phenotypes including a classical form mimicking dystrophic epidermolysis bullosa, an inflammatory presentation mimicking BP, or mucous membrane pemphigoid-like lesions. Mucous membrane pemphigoid (MMP) is the term agreed upon by international consensus for an autoimmune blistering disorder, which affects one or more mucous membrane and may involve the skin. The condition involves a number of different autoantigens in the basement membrane zone. It may result in severe complications from scarring, such as blindness and strictures. Diagnosis of these diseases relies on direct immunofluorescence microscopy studies and immunoserological assays. Management of affected patients is often challenging. We will here review the clinical and immunopathological features as well as the pathophysiology of this group of organ-specific autoimmune diseases. Finally, we will discuss the diagnostic approach and the principles of management in clinical practice.

Dipeptidyl peptidase-4 inhibitor-associated bullous pemphigoid in a patient with acquired reactive perforating collagenosis

Bullous pemphigoid (BP) is a common autoimmune blistering disorder with unknown etiology. Recently, increasing numbers of BP cases which developed under the medication with dipeptidyl peptidase-4 inhibitors (DPP4i), widely used antihyperglycemic drugs, have been reported in published works. Here, we report a case of DPP4i (teneligliptin)-associated BP that developed in a 70-year-old Japanese man. Interestingly, the patient had acquired reactive perforating collagenosis (ARPC), which is also known to be associated with the onset of BP. In the present case, clinical, histopathological and immunological findings suggested that DPP4i rather than ARPC was associated with the onset of BP.

Analysis of the autoimmune response against BP180 and BP230 in ethnic Poles with neurodegenerative disorders and bullous pemphigoid

Recent studies postulated the association between bullous pemphigoid (BP) and neurodegenerative disorders (ND). The autoantibodies to BP180 and/or BP230 may be present not only in BP, but also in ND as neuronal isoforms of these proteins are identified in the central nervous system. However, there are only scant data about the precise pathogenetic mechanisms interlinking ND and BP as well as the immunologic profile in these patients. The aim is to analyze the serological immunopathological profiles (anti-BP180 IgG, anti-BP230 IgG) in BP patients with and without ND in order to identify the specific autoantibody(ies) and corresponding antigens responsible for ND development in BP patients.

Altogether, 82 ethnic Poles with BP and their medical records were examined (62 BP-ND; 20 BP+ND). Levels of serum anti-BP180/BP230 IgG in BP patients were evaluated with ELISAs. The statistical analyses involved Pearson chi-squared test, Mann-Whitney U-test and ranking of autoantibodies.

The prevalence of ND among BP patients was 24.4%. There were no statistically significant differences in autoantigens profiles (anti-BP180/anti-BP230 IgG) between BP+ND and BP-ND groups. There was no relationship between ND development and anti-BP180/anti-BP230 IgG level (p = 0.5933, p = 0.4701, respectively).

The autoantibodies levels of BP+ND and BP-ND patients show insignificant differences suggesting that also in ethnic Poles a hypothetical pathogenetic association of BP and ND, but not only an aging-related epidemiological one, appears to be independent of a particular BP antigen. Nevertheless, it cannot be excluded that phenomena of epitopes spreading, immune cross-reaction and conformational changes in BP180/BP230 may underlie BP development in ND patients.

A multi-hit hypothesis of bullous pemphigoid and associated neurological disease: Is HLA-DQB1*03:01, a potential link between immune privileged antigen exposure and epitope spreading?

Bullous pemphigoid (BP) is the most common autoimmune blistering disease and is linked to IgG recognition of 2 hemidesmosomal antigens, that is, BP230 (BP antigen 1) and BP180 (BP antigen 2, collagen XVII). The association of BP with other systemic diseases, particularly neurocognitive diseases, provides a potential clue in the underlying pathogenesis of BP. The role of HLA-DQB1*03:01 binding to the immunogenic portion of BP180 provides a potential mechanism by which exposure to neuronal collagen BP180 may lead to cutaneous disease. In our proposed multi-hit hypothesis, patients with underlying neuronal disease are exposed to previously sequestered self-antigen, most importantly BP180. Patients with the HLA-DQB1*03:01 allele show an increased T-cell avidity to several epitopes of BP180, particularly the BP180-NC16a domain. Thus, they have a genetic susceptibility to developing BP upon exposure to the target antigen. In a patient with dysregulation of Th1/Th2 balance, anergy is lost and T-cells are subsequently primed resulting in the development of functional autoimmunity against the BP180-NC16a domain leading to clinically overt disease.

The Skin and Parkinson's Disease: Review of Clinical, Diagnostic, and Therapeutic Issues

BACKGROUND

Parkinson's disease (PD) and the skin are related in a number of ways, including clinical abnormalities of the disease itself and skin-related side effects of dopaminergic medication, pumps, and surgical therapies. Recent advances in understanding the role of α-synuclein suggest skin biopsies as a potential diagnostic or even a premotor marker of PD.

METHODS

The PubMed database was searched for publications up to October 2015, and the current evidence on skin-related issues in PD was comprehensively summarized.

RESULTS

The evidence was summarized on the prevalence, etiology, and management of seborrheic dermatitis, sweating dysfunctions, bullous pemphigoid, and malignant melanoma, as well as therapy-related skin disorders, especially those observed in amantadine, rotigotine, apomorphine, and levodopa/carbidopa intestinal gel therapies and deep-brain stimulation. Skin biopsies evaluating the presence of α-synuclein, the density and morphology of cutaneous nerves, and skin fibroblast functions also are discussed.

CONCLUSIONS

Skin disorders are a common manifestation of PD. However, the exact pathophysiology and prevalence of these disorders are not well understood, and more systematic research is needed in this regard. Peripheral tissue biopsies as a diagnostic marker of PD are an exciting avenue in future PD research, although multiple caveats and pending issues need to be solved before they can be used in routine clinical practice.