Demographics and Autoantibody Profiles of Pemphigoid Patients with Underlying Neurologic Diseases

Assessment of relationships between bullous pemphigoid and neurological diseases: A bidirectional two-sample Mendelian randomization study

Bullous pemphigoid (BP) is the most prevalent autoimmune vesiculobullous skin illness that tends to affect the elderly. Growing evidence has hinted a correlation between BP and neurological diseases. However, existing observational studies contained inconsistent results, and the causality and direction of their relationship remain poorly understood. To assess the causal relationship between BP and neurological disorders, including Alzheimer's disease (AD), multiple sclerosis (MS), Parkinson's disease (PD), and stroke. A bidirectional two-sample Mendelian randomization (MR) adopted independent top genetic variants as instruments from the largest accessible genome-wide association studies (GWASs), with BP (n = 218 348), PD (n = 482 730), AD (n = 63 926), stroke (n = 446 696), and MS (n = 115 803). Inverse variance weighted (IVW), MR-Egger, weighted mode methods, weighted median, and simple mode were performed to explore the causal association. Multiple sensitivity analyses, MR-Pleiotropy Residual Sum and Outlier (PRESSO) was used to evaluate horizontal pleiotropy and remove outliers. With close-to-zero effect estimates, no causal impact of BP on the risk of the four neurological diseases was discovered. However, we found that MS was positively correlated with higher odds of BP (OR = 1.220, 95% CI: 1.058-1.408, p = 0.006), while no causal associations were observed between PD (OR = 0.821, 95% CI: 0.616-1.093, p = 0.176), AD (OR = 1.066, 95% CI: 0.873-1.358, p = 0.603), stroke (OR = 0.911, 95% CI: 0.485-1.713, p = 0.773) and odds of BP. In summary, no causal impact of BP on the risk of PD, AD, MS and stroke was detected in our MR analysis. However, reverse MR analysis identified that only MS was positively correlated with higher odds of BP, but not PD, AD and stroke.

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.

Histopathology of autoimmune bullous dermatoses: What's new?

Autoimmune bullous dermatoses are characterized by the presence of tissue-bound and often circulating pathogenic autoantibodies targeting structural components of the skin and/or mucous membranes. The diagnostic workup for this heterogeneous group of disorders consists of a multi-step process, of which the light microscopic examination is a crucial component. This review is organized following a classification scheme that is based on two main histopathologic features, namely level of intraepithelial split and composition of the inflammatory infiltrate. Overall, we aim to place emphasis on the histopathologic clues that can assist pathologists in differential diagnosis and review the updates in the literature.

The Relationship Between Alzheimer's Disease and Skin Diseases: A Review

Alzheimer's disease is the most common type of dementia placing a heavy burden on the healthcare system worldwide. Skin diseases are also one of the most common health problems. Several skin diseases are associated with Alzheimer's disease through different mechanisms. This review summarizes the relationship between Alzheimer's disease and several types of skin diseases, including bullous pemphigoid, hidradenitis suppurativa, psoriasis, skin cancer, and cutaneous amyloidosis, and provides suggestions based on these associations. Neurologists, dermatologists, and general practitioners should be aware of the relationship between Alzheimer's disease and skin diseases. Dermatology/neurology consultation or referral is necessary when needed.

Comorbidities of bullous pemphigoid: A single-center retrospective case-control study from Turkey

Although significant associations between bullous pemphigoid (BP) and certain comorbidities, primarily subtypes of neurological disorders, have been reported in several populations, it has yet to be demonstrated whether a correlation exists between pre-existing comorbidities and serum titers of anti-BP180 and 230 immunoglobulin G (IgG) antibodies among BP patients. The aim of the current study is to investigate the demographic and clinical features of BP patients in a large series from Turkey, determine the prevalence of pre-existing neurological and systemic disorders, and assess the correlation between the existence of certain comorbidities and basal serum titers of anti-BP180 and 230 IgG autoantibodies. Thus, data from 145 BP patients diagnosed in the study's center between 1987 and 2017 were retrospectively analyzed and compared with 310 age- and sex-matched control subjects. The serum titers of anti-BP 180 and 230 IgG autoantibodies were compared between the patients with and without comorbidities and its subtypes among 55 patients with available serum basal anti-BP levels. Twenty-eight of the BP patients (19.3%) had already been diagnosed with at least one neurological disorder at the onset of BP. According to regression analysis, preexisting neurological disorders (p = 0.017), stroke (p = 0.017), and malignancies (p = 0.005) were found to be higher among the study's BP patients than the controls. The serum titers of anti-BP180 and 230 that were measured at the time of diagnosis were significantly higher in patients with neurological disorders than in patients without neurological disorders (p = 0.042; p = 0.018). Among the pre-existing comorbidities, neurological disorders, particularly stroke, and malignancies were found to be significantly connected to the occurrence of BP in the selected Turkish population. The high titers of serum anti-BP180 and 230 IgG antibodies at the time of BP diagnoses may highlight undiagnosed pre-existing neurological disorders by provoking suspicion.

Non-Bullous Pemphigoid: A Single-Center Retrospective Study

INTRODUCTION

Bullous pemphigoid (BP) is an autoimmune disease that typically presents with blisters, but sometimes early lesions may be eczematous, maculopapular, or urticarial. The aim of the present study was to highlight possible differences between typical bullous and non-bullous pemphigoid (NBP) and compare results with the literature. Material & methods: Patients receiving a diagnosis of BP between January 2000 and December 2019 were analyzed. Patients who developed a blister after 3 months from the onset of pruritus were considered as NBP. Demographic features, clinical findings at diagnosis and at 2-year follow-up, histological features, auto-antibodies titers, comorbidities and their treatment were retrieved. Categorical variables were evaluated for normal distribution using a histogram and a Q-Q plot. The χ2 and Fisher's exact tests were used to compare categorical variables between the groups. Continuous variables were compared between the groups using analysis of variance and the independent-samples t test. For multivariate analysis, logistic regression was performed.

RESULTS

A total of 532 patients received a diagnosis of BP. A total of 122 patients were enrolled in the study; 63 were females, and the mean age at the diagnosis was 77.2 years (±11.9 SD). 98 were affected by BP and 24 were categorized as NBP. Mean time to diagnosis was 2.9 months (±5.8 SD) for BP and 30.4 months (±59.8 SD) for NBP (p = 0.0001). Skin manifestations in NBP patients were, in order of frequency: urticarial, papular or nodular, eczematous, and excoriations. Pruritus intensity was high but similar in the two groups (Numerical Rating Scale - NRS, 9.3 vs. 8.9). Seven out of 24 NBP patients (29%) never developed blisters; the other patients developed blisters after a mean follow-up time of 24.9 months (±54.9 SD). NBP patients had a more frequent history of myocardial infarction than BP patients (37.5 vs. 10.2%; p < 0.003). More NBP patients were taking diuretics than BP patients (66.7 vs. 49%; p = 0.03). NBP patients had a worse response to pruritus compared to BP patients at 2 years (NRS 3.7 vs. 11; p 0.001).

CONCLUSIONS

NBP patients have a delayed diagnosis and may be at an increased risk of cardiovascular disease, especially myocardial infarction. Severely and persistently itchy skin disorders in aged patients should be investigated for BP diagnosis.

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.

Bullous Pemphigoid Associated with Multiple System Atrophy: Case Series

Background

Bullous pemphigoid (BP) is an autoimmune blistering dermatosis associated with a number of neurological conditions, including idiopathic Parkinson's disease (IPD). Only 1 case of BP in a patient with multiple system atrophy (MSA) has been reported.

Cases

We report 3 cases of men with probable MSA who developed bullous pemphigoid at a latency of 4–6 years from MSA symptom onset.

Conclusions

Skin α‐synuclein deposition in neurodegenerative conditions such as IPD and MSA may be a potential substrate for the exposure of BP‐related antigens. Alternatively, central neurodegeneration may expose antigens as a substrate for cross‐reactivity and BP pathogenesis. Our report suggests an association between BP and MSA, in addition to the previously documented association with IPD.

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.

Neurological Cancer is a Risk Factor for Bullous Pemphigoid: 11-Year Population-Based Cohort Study

BACKGROUND

There is evidence suggesting an association between bullous pemphigoid (BP) and a range of neurological diseases. Whether neurological cancer is a risk factor for BP remains unknown.

OBJECTIVE

The aim of the study was to investigate the risk of subsequent BP among patients with neurological cancer.

METHODS

This nationwide population-based cohort study was based on data obtained from the Taiwan National Health Insurance Research Database between 2000 and 2012. A total of 8313 patients with neurological cancer and 33,252 age-, sex-, and index-date-matched controls were recruited. The hazard ratio (HR) for subsequent BP in patients with neurological cancer was analyzed using a Cox model and Fine-Gray competing risk model, with mortality as the competing event.

RESULTS

The incidence rates of BP per 100,000 person-years were 37.2 for patients with neurological cancer and 6.8 for controls. The crude incidence rate ratio was 5.49 (95% confidence interval [CI] 2.18-13.30). The mean time to occurrence of BP was 4.48 ± 3.40 years for patients with neurological cancer. Neurological cancer (HR 9.65, 95% CI 3.76-24.77 for the Cox model; HR 2.41, 95% CI 1.14-5.14 for the competing risk model), age per year (HR 1.10, 95% CI 1.05-1.15 for the Cox model; HR 1.06, 95% CI 1.02-1.09 for the competing risk model), and dementia (HR 6.31, 95% CI 2.49-15.99 for the Cox model; HR 7.50, 95% CI 2.84-19.85 for the competing risk model) significantly increased the risk of BP.

CONCLUSIONS

Neurological cancer increased the risk for subsequent BP by 2.4-fold, with a relatively short gap of 4.5 years.

The pathogenesis of bullous skin diseases

Bullous skin diseases are a group of dermatoses characterized by blisters and bullae in the skin and mucous membranes. The etiology and pathogenesis of bullous skin diseases are not completely clear. The most common are pemphigus and bullous pemphigoid (BP). Autoantibodies play critical roles in their pathogenesis. Abnormalities in the adhesion between keratinocytes in patients with pemphigus leads to acantholysis and formation of intra-epidermal blisters. Anti-desmoglein autoantibodies are present both in the circulation and skin lesions of patients with pemphigus. The deficient adhesion of keratinocytes to the basement membrane in BP patients gives rise to subepidermal blisters. Autoantibodies against the components of hemidesmosome can be detected in BP patients. Many novel therapeutics based on knowledge of the pathogenesis have emerged in recent years.