Incidence, prevalence and mortality of bullous pemphigoid in England 1998-2017: a population-based cohort study

Functional decline among bullous pemphigoid patients: A retrospective monocentric cohort study

BACKGROUND

Bullous pemphigoid (BP) affects older patients with numerous comorbidities. The impact of BP on patient autonomy remains poorly understood.

OBJECTIVES

To assess the frequency and factors associated with functional decline (FD) in BP.

METHODS

In this retrospective monocentric study, we selected patients aged ≥75 years with BP diagnosed between 1 January 2015 and 31 December 2021 and followed for more than 3 months. We assessed activity limitation at diagnosis and included patients with no or mild activity limitation. We described FD and its associated factors at 6 weeks and 3 months. FD was qualified as moderate or severe. Age, comorbidities (CIRS-G score), BP characteristics at diagnosis (including palms and soles involvement) and hospitalization were collected. Factors associated with FD were investigated through univariate and multivariate logistic regression models. Worsening of previous comorbidities or new comorbidities at Week 6 were collected.

RESULTS

One hundred and thirty-one patients were included (mean age 85 years), 75 (57.3%) had no activity limitation, and 56 (42.7%) a mild activity limitation at baseline. At Week 6, FD was observed in 44 (33.6%) patients, including 23 out of 75 (30.7%) with no activity limitation and 21 out of 56 (37.5%) with mild activity limitation at baseline. FD was moderate in 20 cases (45.5%) and severe in 24 (54.5%) and persisted at Month 3 in 37 (84%) patients. By multivariate analysis, factors associated with FD were a CIRS-G score >7, palms and soles involvement and anti-BP180 antibodies level. Fifty (38.2%) patients experienced a worsening of their pre-existing comorbidities or a new one.

CONCLUSION

FD is often observed in patients with BP, especially in those with severe symptoms, palms and soles involvement and comorbidities. A comprehensive, multidisciplinary approach involving geriatric assessments should be adopted to manage these patients.

Identification of Risk Factors for Gliptin-associated Bullous Pemphigoid among Diabetic Patients

Drug-associated bullous pemphigoid has been shown to follow long-term gliptin (dipeptidyl-peptidase 4 inhibitors) intake. This study aimed at identifying risk factors for gliptin-associated bullous pemphigoid among patients with type 2 diabetes. A retrospective study was conducted in a tertiary centre among diabetic patients exposed to gliptins between the years 2008-2021. Data including demographics, comorbidities, medications, and laboratory results were collected using the MDClone platform. Seventy-six patients with type 2 diabetes treated with dipeptidyl-peptidase 4 inhibitors who subsequently developed bullous pemphigoid were compared with a cohort of 8,060 diabetic patients exposed to dipeptidyl-peptidase 4 inhibitors who did not develop bullous pemphigoid. Based on a multivariable analysis adjusted for age and other covariates, Alzheimer's disease and other dementias were significantly more prevalent in patients with bullous pemphigoid (p = 0.0013). Concomitant use of either thiazide or loop diuretics and gliptin therapy was associated with drug-associated bullous pemphigoid (p < 0.0001 for both). While compared with sitagliptin, exposure to linagliptin and vildagliptin were associated with bullous pemphigoid with an odds ratio of 5.68 and 6.61 (p < 0.0001 for both), respectively. These results suggest gliptins should be prescribed with caution to patients with type 2 diabetes with coexisting Alzheimer's and other dementias, or patients receiving long-term use of thiazides and loop diuretics. The use of sitagliptin over linagliptin and vildagliptin should be preferred in these patients.

Risk of bullous pemphigoid and pemphigus in patients on chronic dialysis: A nationwide population-based cohort study

Bullous pemphigoid has a high incidence among dialysis patients. However, whether or not chronic dialysis is an independent risk factor of bullous pemphigoid remains unclear. We aimed to investigate the effect of chronic dialysis on the development of bullous pemphigoid and pemphigus. We performed a retrospective cohort study using records from Taiwan's National Health Insurance Research Database between 2008 and 2019. We identified a dialysis cohort that included patients on chronic hemodialysis and peritoneal dialysis, and the hazard ratios (HRs) for bullous pemphigoid and pemphigus were compared with those of a sex-, age-, and index-matched cohort, then the results were adjusted for various confounding factors. Among 93 538 patients on chronic dialysis and 93 538 patients in the control group, 287 and 139 developed incident bullous pemphigoid, and 45 and 35 developed incident pemphigus after a median follow-up of 3.7 and 5.6 years, respectively. The incidence rates of bullous pemphigoid in the dialysis patients and the control group were 74.2 and 25.2 per 100 000 person-years, respectively (difference between groups, P < 0.0001). The incidence rates of pemphigus in the dialysis patients and the control group were 11.6 and 6.3 per 100 000 person-years, respectively (difference between groups, P < 0.01). Cox proportional hazard adjustment showed the HR for bullous pemphigoid in dialysis patients was 2.12 (95% confidence interval [CI] 1.64-2.74, P < 0.0001) compared with the control group. Dialysis patients aged <75 years had an even higher risk of bullous pemphigoid development (5- to 8-fold) than the control group. The adjusted HR for pemphigus was not elevated in dialysis patients (adjusted HR 1.52, 95% CI 0.87-2.67, P = 0.14). Chronic dialysis is an independent risk factor for developing bullous pemphigoid, but not a risk factor for pemphigus. Physicians should be aware of the predisposition of chronic dialysis patients to bullous pemphigoid.

Identification of gut microbiota dysbiosis in bullous pemphigoid under different disease activity

Bullous pemphigoid (BP) is a severe autoimmune blistering disease affecting patients' quality of life. Gut microbiota (GM) dysbiosis have been investigated to be associated with multiple autoimmune diseases. However, the relationship between GM and BP onset and remission remains to be established by a systematic study. We conducted a study that enrolled 24 patients with BP onset (BP group), 24 patients under remission stage (BP-R group) and 24 healthy controls (HC group). We applied 16S rRNA sequencing on faecal samples and revealed a separation of the microbiota structure. At the family level, Lachnospiraceae, Prevotellaceae and Veillonellaceae were more abundant in the HC and BP-R groups, while Bacteroidaceae, Ruminococcaceae and Enterobacteriaceae were more abundant in the BP group. Bugbase analysis revealed the potentially pathogenic bacteria had an increasing trend in the BP group compared with the HC group and this variation vanished in the BP-R group. At the amplicon sequence variants (ASV) level, Bacteroides ovatus (ASV40) and Veillonella dispar (ASV140) significantly decreased, while Prevotella copri (ASV54) increased in the BP group compared to the HC and BP-R groups. The HC group and BP-R group shared similar abundance. Furthermore, by correlation analysis, we investigated key ASVs correlated with clinical parameters and found some discriminate biomarkers between the BP and BP-R groups. Our study established a dynamic GM profile in BP patients under different disease activity, providing a new direction to understand the role of GM in BP pathogenesis and therapeutic effects.

Accurate diagnosis of bullous pemphigoid requires multiple health care visits

Introduction

Accurate use of diagnostic codes is crucial for epidemiological and genetic research based on electronic health record (EHR) data.

Methods

This retrospective study validated the International Classification of Diseases (ICD)-10 diagnostic code L12.0 for bullous pemphigoid (BP) using EHR data from two Finnish university hospitals. We found 1225 subjects with at least one EHR entry of L12.0 between 2009 and 2019. BP diagnosis was based on clinical findings characteristic of BP and positive findings on direct immunofluorescence (DIF), BP180-NC16A enzyme-linked immunosorbent assay (ELISA) or indirect immunofluorescence (IIF) assay.

Results

True BP was found in 901 patients; the positive predictive value (PPV) for L12.0 was 73.6% (95% CI 71.0-76.0). L12.0 was more accurately registered in dermatology units than any specialized health care units (p<0.001). Including patients with multiple L12.0 registrations (≥3), increased the accuracy of the L12.0 code in both dermatology units and other settings.

Discussion

One diagnostic code of L12.0 is not enough to recognize BP in a large epidemiological data set; including only L12.0 registered in dermatology units and excluding cases with <3 L12.0 record entries markedly increases the PPV of BP diagnosis.

Case Report: The many faces of bullous pemphigoid

The pemphigoid group comprises a number of bullous skin diseases with autoantibodies against different constituents of the basement membrane zone that result in subepidermal detachment and clinically characteristic tense blisters, erosions, urticarial erythema, and itching. Apart from the most frequent type of bullous pemphigoid with antibodies against BP180, which is found predominantly in elderly patients, the disease may present at other ages and different pathogenic conditions. Here, four cases are presented of young age (3 months and 25, 34, and 46 years) and in association with vaccination, pregnancy, or metastatic cancer. Though anti-BP180 was found in all cases, a different pathogenic background may be found in any of them, resulting in characteristic clinical manifestation, yet demanding specifically adapted therapeutic approaches.

Interventions for bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is the most common autoimmune blistering disease. Oral steroids are the standard treatment. We have updated this review, which was first published in 2002, because several new treatments have since been tried.

OBJECTIVES

To assess the effects of treatments for bullous pemphigoid.

SEARCH METHODS

We updated searches of the following databases to November 2021: Cochrane Skin Specialised Register, CENTRAL, MEDLINE, and Embase. We searched five trial databases to January 2022, and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs).

SELECTION CRITERIA

RCTs of treatments for immunofluorescence-confirmed bullous pemphigoid.

DATA COLLECTION AND ANALYSIS

At least two review authors, working independently, evaluated the studies against the review's inclusion criteria and extracted data from included studies. Using GRADE methodology, we assessed the certainty of the evidence for each outcome in each comparison. Our primary outcomes were healing of skin lesions and mortality.

MAIN RESULTS

We identified 14 RCTs (1442 participants). The main treatment modalities assessed were oral steroids, topical steroids, and the oral anti-inflammatory antibiotic doxycycline. Most studies reported mortality but adverse events and quality of life were not well reported. We decided to look at the primary outcomes 'disease control' and 'mortality'. Almost all studies investigated different comparisons; two studies were placebo-controlled. The results are therefore based on a single study for each comparison except azathioprine. Most studies involved only small numbers of participants. We assessed the risk of bias for all key outcomes as having 'some concerns' or high risk, due to missing data, inappropriate analysis, or insufficient information. Clobetasol propionate cream versus oral prednisone Compared to oral prednisone, clobetasol propionate cream applied over the whole body probably increases skin healing at day 21 (risk ratio (RR 1.08, 95% confidence interval (CI) 1.03 to 1.13; 1 study, 341 participants; moderate-certainty evidence). Skin healing at 21 days was seen in 99.8% of participants assigned to clobetasol and 92.4% of participants assigned to prednisone. Clobetasol propionate cream applied over the whole body compared to oral prednisone may reduce mortality at one year (RR 0.73, 95% CI 0.53 to 1.01; 1 study, 341 participants; low-certainty evidence). Death occurred in 26.5% (45/170) of participants assigned to clobetasol and 36.3% (62/171) of participants assigned to oral prednisone. This study did not measure quality of life. Clobetasol propionate cream may reduce risk of severe complications by day 21 compared with oral prednisone (RR 0.65, 95% CI 0.50 to 0.86; 1 study, 341 participants; low-certainty evidence). Mild clobetasol propionate cream regimen (10 to 30 g/day) versus standard clobetasol propionate cream regimen (40 g/day) A mild regimen of topical clobetasol propionate applied over the whole body compared to the standard regimen probably does not change skin healing at day 21 (RR 1.00, 95% CI 0.97 to 1.03; 1 study, 312 participants; moderate-certainty evidence). Both groups showed complete healing of lesions at day 21 in 98% participants. A mild regimen of topical clobetasol propionate applied over the whole body compared to the standard regimen may not change mortality at one year (RR 1.00, 95% CI 0.75 to 1.32; 1 study, 312 participants; low-certainty evidence), which occurred in 118/312 (37.9%) participants. This study did not measure quality of life. A mild regimen of topical clobetasol propionate applied over the whole body compared to the standard regimen may not change adverse events at one year (RR 0.94, 95% CI 0.78 to 1.14; 1 study, 309 participants; low-certainty evidence). Doxycycline versus prednisolone Compared to prednisolone (0.5 mg/kg/day), doxycycline (200 mg/day) induces less skin healing at six weeks (RR 0.81, 95% CI 0.72 to 0.92; 1 study, 213 participants; high-certainty evidence). Complete skin healing was reported in 73.8% of participants assigned to doxycycline and 91.1% assigned to prednisolone. Doxycycline compared to prednisolone probably decreases mortality at one year (RR 0.25, 95% CI 0.07 to 0.89; number needed to treat for an additional beneficial outcome (NNTB) = 14; 1 study, 234 participants; moderate-certainty evidence). Mortality occurred in 2.4% (3/132) of participants with doxycycline and 9.7% (11/121) with prednisolone. Compared to prednisolone, doxycycline improved quality of life at one year (mean difference 1.8 points lower, which is more favourable on the Dermatology Life Quality Index, 95% CI 1.02 to 2.58 lower; 1 study, 234 participants; high-certainty evidence). Doxycycline compared to prednisolone probably reduces severe or life-threatening treatment-related adverse events at one year (RR 0.59, 95% CI 0.35 to 0.99; 1 study, 234 participants; moderate-certainty evidence). Prednisone plus azathioprine versus prednisone It is unclear whether azathioprine plus prednisone compared to prednisone alone affects skin healing or mortality because there was only very low-certainty evidence from two trials (98 participants). These studies did not measure quality of life. Adverse events were reported in a total of 20/48 (42%) participants assigned to azathioprine plus prednisone and 15/44 (34%) participants assigned to prednisone. Nicotinamide plus tetracycline versus prednisone It is unclear whether nicotinamide plus tetracycline compared to prednisone affects skin healing or mortality because there was only very low-certainty evidence from one trial (18 participants). This study did not measure quality of life. Fewer adverse events were reported in the nicotinamide group. Methylprednisolone plus azathioprine versus methylprednisolone plus dapsone It is unclear whether azathioprine plus methylprednisolone compared to dapsone plus methylprednisolone affects skin healing or mortality because there was only very low-certainty evidence from one trial (54 participants). This study did not measure quality of life. A total of 18 adverse events were reported in the azathioprine group and 13 in the dapsone group.

AUTHORS' CONCLUSIONS

Clobetasol propionate cream applied over the whole body is probably similarly effective as, and may cause less mortality than, oral prednisone for treating bullous pemphigoid. Lower-dose clobetasol propionate cream applied over the whole body is probably similarly effective as standard-dose clobetasol propionate cream and has similar mortality. Doxycycline is less effective but causes less mortality than prednisolone for treating bullous pemphigoid. Other treatments need further investigation.

Targeting type 2 inflammation in bullous pemphigoid: current and emerging therapeutic approaches

Bullous pemphigoid (BP) is one of the most common autoimmune bullous diseases and mainly affects an elderly population with multi-morbidity. Due to the frailty of many BP patients, existing treatment options are limited. The blisters associated with BP result from IgG and IgE autoantibodies binding to the central components of hemidesmosome, BP180, and BP230, stimulating a destructive inflammatory process. The known characteristic features of BP, such as intense pruritus, urticarial prodrome, peripheral eosinophilia, elevated IgE, as well as recent expanding evidence from in vitro and in vivo studies implicate type 2 inflammation as an important driver of BP pathogenesis. Type 2 inflammation is an inflammatory pathway involving a subset of CD4+ T cells that secrete IL-4, IL-5, and IL-13, IgE-secreting B cells, and granulocytes, such as eosinophils, mast cells, and basophils. It is believed that effectors in type 2 inflammation may serve as novel and effective treatment targets for BP. This review focuses on recent understandings of BP pathogenesis with a particular emphasis on the role of type 2 inflammation. We summarize current clinical evidence of using rituximab (B-cell depletion), omalizumab (anti-IgE antibody), and dupilumab (anti-IL-4/13 antibody) in the treatment of BP. The latest advances in emerging targeted therapeutic approaches for BP treatment are also discussed.

Effect of early initiation of steroid-sparing drugs in patients with bullous pemphigoid

Introduction

Bullous pemphigoid (BP) can be treated using systemic and topical glucocorticoids and/or other immunomodulatory agents. However, the long-term use of systemic glucocorticoids causes severe adverse side effects. This study was aimed at investigating whether the early initiation of corticosteroid-sparing therapy (CST) in BP patients results in better outcomes than late or no CST.

Method

We retrospectively identified all BP patients referred to the tertiary center, of the Department of Dermatology and Venerology, Aarhus University Hospital, Denmark, from 2015 to 2021. Patients' demographics, comorbidities, treatment, remission of BP, length of admission, relapse, and 1-year mortality were recorded. All patients who received CST were dichotomised into two groups: initiated with CST <28 or >28 days. The groups were compared using t-tests. Additionally, all patients who received CST were compared with those who received systemic glucocorticoids alone. Our cohort was compared with that of a previous study (2006-2013) performed in our department. In 2015, we revised our BP treatment guidelines to include the early initiation of CST.

Results

On comparing the group of patients initiated with CST <28 versus >28 days, we found no significant differences in the complications or mortality between the groups (p = 0.63 and p=0.79, respectively). The <28 days group had a lower rate of relapse (p < 0.05). On comparing data from this study with those from the previous study, conducted before we revised our treatment guideline, we found a reduced initial dose of prednisolone and reduced admission time in this study. No significant differences were found between patients treated with CST and those treated with systemic glucocorticoids alone.

Conclusion

The rate of complications and 1-year mortality did not differ significantly between the two subgroups in this study. The relapse rate was lower in the CST <28 days group than in the CST >28 days group. The initial dose of prednisolone and admission time were reduced in this study compared with those in the previous study performed before the implementation of a local treatment guideline recommending the early initiation of CST.

The Role of Sex and Gender in Dermatology - From Pathogenesis to Clinical Implications

BACKGROUND

Sex and gender have increasingly been recognized as significant risk factors for many diseases, including dermatological conditions. Historically, sex and gender have often been grouped together as a single risk factor in the scientific literature. However, both may have a distinct impact on disease incidence, prevalence, clinical presentation, severity, therapeutic response, and associated psychological distress.

OBJECTIVES AND PROJECT DESCRIPTION

The mechanisms that underlie differences in skin diseases between males, females, men, and women remain largely unknown. The specific objectives of this review paper are:To highlight the biological differences between males and females (sex), as well as the sociocultural differences between men and women (gender) and how they impact the integumentary system.To perform a literature review to identify important sex- and gender-related epidemiological and clinical differences for various skin conditions belonging to a range of disease categories and to discuss possible biological and sociocultural factors that could explain the observed differences.To discuss dermatological skin conditions and gender-affirming treatments within the transgender community, a population of individuals who have a gender identity which is different than the gender identity they were assigned at birth.

FUTURE IMPACT

With the rising number of individuals that identify as non-binary or transgender within our increasingly diverse communities, it is imperative to recognize gender identity, gender, and sex as distinct entities. By doing so, clinicians will be able to better risk-stratify their patients and select treatments that are most aligned with their values. To our knowledge, very few studies have separated sex and gender as two distinct risk factors within the dermatology literature. Our article also has the potential to help guide future prevention strategies that are patient-tailored rather than using a universal approach.

Attenuation of OX40 signaling suppression by age disrupts peripheral deletion of CD4+ T cells specific for the epidermal autoantigen desmoglein 3

Various autoimmune responses increase with age, but the underlying mechanism is not clear. In this study, we used CD4⁺ T cells expressing a transgenic T cell receptor specific for desmoglein 3 (Dsg3), which is the target antigen of the autoimmune bullous disease pemphigus vulgaris, to examine how peripheral immunological tolerance against pathogenic autoreactive CD4⁺ T cells changes with age. Dsg3-specific T cells were deleted within 14 days after adoptive transfer into young mice (8 weeks old), while they escaped deletion when transferred into older mice over 42 weeks old. Dsg3-specific T cells produced higher levels of the proinflammatory cytokine IFN-γ in aged mice than in young mice. In addition, the expression levels of both OX40 and Birc5, which are important for cell survival in T cell clonal proliferation, were higher in aged than in young mice. The dysfunction in suppressing proinflammatory cytokine secretion and Birc5 upregulation in Dsg3-specific autoreactive T cells may reflect an aspect of the preliminary steps in autoimmune disease development in the aged population. Understanding this mechanism may lead to better risk evaluation of autoimmune disease development and to onset prevention.

Worldwide epidemiologic factors in pemphigus vulgaris and bullous pemphigoid

Autoimmune blistering diseases such as bullous pemphigoid (BP) and pemphigus vulgaris (PV) are complex, multifactorial, and polygenic diseases, whose exact pathogenesis is difficult to pinpoint. Research aimed at elucidating the associated epidemiologic risk factors of these two diseases has been hampered by their rare disease status. Further, a lack of centralization and standardization of available data makes the practical application of this information challenging. In order to collate and clarify the available literature we comprehensively reviewed 61 PV articles from 37 different countries and 35 BP articles from 16 different countries addressing a range of disease relevant clinical parameters including age of onset, sex, incidence, prevalence, and HLA allele association. The reported incidence of PV ranged from 0.098 to 5 patients per 100,000 people, while BP ranged from 0.21 to 7.63 patients per 100,000. Prevalence of PV ranged from 0.38 to 30 per 100,000 people and BP ranged from 1.46 to 47.99 per 100,000. The mean age of onset in patients ranged from 36.5 to 71 years for PV and 64 to 82.6 years for BP. Female-to-male ratios ranged from 0.46 to 4.4 in PV and 1.01 to 5.1 in BP. Our analysis provides support for the reported linkage disequilibrium of HLA DRB1*0402 (an allele previously shown to be associated with PV) and DQB1*0302 alleles in Europe, North America, and South America. Our data also highlight that HLA DQB1*0503 (also known to be associated with PV) appears in linkage disequilibrium with DRB1*1404 and DRB1*1401, mainly in Europe, the Middle East, and Asian countries. The HLA DRB1*0804 allele was only associated with PV in patients of Brazilian and Egyptian descent. Only two HLA alleles were reported as associated with BP more than twice in our review, DQB1*0301 and DQA1*0505. Collectively, our findings provide detailed insights into the variation of disease parameters relevant to PV and BP that can be expected to inform future work aimed at unraveling the complex pathogenesis of these conditions across the globe.

Association between bullous pemphigoid and atopic dermatitis: a population-based case-control study in Taiwan

Although bullous pemphigoid (BP) and atopic dermatitis (AD) share pathogenic mechanisms, their relationship remains controversial. Therefore, we conducted a population-based case-control study to investigate the association between BP and AD in Taiwan. Based on the Taiwan National Health Insurance Research Database, 9344 patients with BP and 18,688 age- and sex-matched controls were enrolled between 2000 and 2013. Furthermore, the study included 7,196 BP patients and 14,392 controls, matched for age, sex, and propensity score of comorbidities, with a case to controls ratio of 1:2. Logistic regression analysis was performed to examine the association between AD and BP. In the age- and sex-matched cohorts, AD (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.50-1.95) was independently associated with BP. In the age, sex, and comorbidities-matched cohorts, AD (OR 1.76, 95% CI 1.55-2.00) remained a significant risk factor for BP. Other significant risk factors included psoriasis, hypertension, diabetes mellitus, chronic kidney disease, chronic obstructive pulmonary disease, neuropsychiatric diseases, and autoimmune connective tissue disease. Limitations of this study include the lack of information on disease severity and phenotypes of BP and misclassification of diseases as potential sources of bias. In conclusion, AD increased the risk of developing BP by 76%, and this association was independent of many BP comorbidities. Further studies are warranted to investigate the clinical and pathophysiological relevance of factors contributing to BP and AD.

Can Methotrexate Be Employed as Monotherapy for Bullous Pemphigoid? Analysis of Efficiency and Tolerance of Methotrexate Treatment in Patients with Bullous Pemphigoid

The European Academy of Dermatology and Venerology (EADV) consensus states that the treatment of choice for bullous pemphigoid is systemic glucocorticosteroid therapy. Bearing in mind that long-term steroid therapy is associated with numerous side effects, an effective and safer treatment regimen for these patients is still being sought. A retrospective analysis was performed of the medical reports of patients with diagnosed bullous pemphigoid. The study included 40 patients with moderate or severe disease, and who had continued ambulatory treatment for at least six months. The patients were divided into two groups: one treated with methotrexate in monotherapy, or with combined methotrexate and systemic steroid therapy. A slightly better survival rate was noted in the methotrexate group. No significant differences were observed between the groups in time to achieve clinical remission. The combination therapy group demonstrated more frequent disease recurrence and exacerbations during treatment, and a higher mortality rate. None of the patients in either group presented with severe side effects related to methotrexate treatment. The treatment of bullous pemphigoid with methotrexate in monotherapy is an effective and safe therapeutic method for elderly patients.

What's new in the pathogeneses and triggering factors of bullous pemphigoid

Bullous pemphigoid (BP) is a subepidermal blistering disease induced by autoantibodies to type XVII collagen (COL17, also called BP180) and BP230. Previous studies using patients' samples and animal disease models elucidated the complement-dependent and complement-independent pathways of blister formation, the pathogenic roles of immune cells (T and B cells, macrophages, mast cells, neutrophils, eosinophils), and the pathogenicity of IgE autoantibodies in BP. This review introduces the recent progress on the mechanism behind the epitope-spreading phenomenon in BP, which is considered to be important to understand the chronic and intractable disease course of BP, and the pathogenicity of anti-BP230 autoantibodies, mainly focusing on studies that used active disease models. To clarify the pathogenesis of BP, the mechanism behind the breakdown of immune tolerance to BP antigens should be investigated. Recent studies using various experimental models have revealed important roles for regulatory T cells in the maintenance of self-tolerance to COL17 and BP230 as well as in the suppression of inflammation triggered by the binding of antibodies to COL17. Notably, physical stresses such as trauma, thermal burns, bone fractures, irradiation and ultraviolet exposure, some pathologic conditions such as neurological diseases and hematological malignancies, and the use of dipeptidyl peptidase-IV inhibitors and immune checkpoint inhibitors have been reported as triggering factors for BP. These factors and certain underlying conditions such as genetic background, regulatory T-cell dysfunction or aging might synergistically affect some individuals and eventually induce BP. Further studies on the breakdown of self-tolerance and on the identification of key molecules that are relevant to blister formation and inflammation may expand our understanding of BP's etiology and may lead to the development of novel therapeutic approaches.

Autoimmune pre-disease

Approximately 5% of the world-wide population is affected by autoimmune diseases. Overall, autoimmune diseases are still difficult to treat, impose a high burden on patients, and have a significant economic impact. Like other complex diseases, e.g., cancer, autoimmune diseases develop over several years. Decisive steps in the development of autoimmune diseases are (i) the development of autoantigen-specific lymphocytes and (often) autoantibodies and (ii) potentially clinical disease manifestation at a later stage. However, not all healthy individuals with autoantibodies develop disease manifestations. Identifying autoantibody-positive healthy individuals and monitoring and inhibiting their switch to inflammatory autoimmune disease conditions are currently in their infancy. The switch from harmless to inflammatory autoantigen-specific T and B-cell and autoantibody responses seems to be the hallmark for the decisive factor in inflammatory autoimmune disease conditions. Accordingly, biomarkers allowing us to predict this progression would have a significant impact. Several factors, such as genetics and the environment, especially diet, smoking, exposure to pollutants, infections, stress, and shift work, might influence the progression from harmless to inflammatory autoimmune conditions. To inspire research directed at defining and ultimately targeting autoimmune predisease, here, we review published evidence underlying the progression from health to autoimmune predisease and ultimately to clinically manifest inflammatory autoimmune disease, addressing the following 3 questions: (i) what is the current status, (ii) what is missing, (iii) and what are the future perspectives for defining and modulating autoimmune predisease.

Researching trends in pemphigoid diseases: A bibliometric study of the top 100 most cited publications

Background

In the field of autoimmune and inflammatory disorders, different approaches were applied to provide information regarding disease activity, comorbidities, epidemiological reports and risk factors. However, no previous studies had thoroughly analyzed the research trend in the field, and the bibliometric analysis focusing on pemphigoid diseases was available. The objective of the current study was to evaluate the current research trend in the field.

Methods

A search has been conducted for the Web of Science database based on various subcategories of pemphigoid diseases. Detailed information including articles' publication types, Author information, citation, and publication information was attained for further analysis.

Results

Within the 6,995 studies, the top 100 most-cited articles were extracted for analysis. Among the top 100 studies, 70% of the studies focused on bullous pemphigoid. More than 60% of the top 100 studies were studies with original data. Furthermore, 30% of the studies were guidelines and narrative reviews. For the issues primarily focused on, most of the high-impact studies described the molecular mechanism of pemphigoid diseases (26%), managements (19%), risk factors of pemphigoid diseases (17%). Additionally, some other studies provided general review or discussed about the issue of epidemiology, diagnosis/definition, comorbidities and clinical characteristics of pemphigoid diseases.

Conclusion

This comprehensive bibliographic study of pemphigoid diseases provided an overview of current research focuses in the field. Topics such as disease management, molecular mechanism of pathogenesis, and drug-inducing pemphigoid diseases were highly mentioned in the most-cited studies. For researchers and clinicians, the researching trend and study focus in the top-100 cited studies could serve as a potential reference for future investigation and patient management.

Analysis of the clinical characteristics of pembrolizumab-induced bullous pemphigoid

Background

Pembrolizumab, a programmed cell death protein 1 checkpoint inhibitor, is a novel drug used to treat a variety of advanced malignancies. However, it can also result in many immune-related adverse events, with cutaneous toxicities being the most frequent. Regarding pembrolizumab-induced skin adverse reactions, bullous pemphigoid (BP) has the worst effects on quality of life. Recently, there have been more and more reports of BP incidents resulting from pembrolizumab therapy in patients with cancer. This study aimed to define the clinical characteristics, diagnosis and management of pembrolizumab-induced BP and identify potential differences between classical BP and pembrolizumab-induced BP.

Methods

Case reports, case series, and case analyses of pembrolizumab-induced BP up to 10 December 2022 were collected for retrospective analysis.

Results

Our study included 47 patients (33 males and 14 females) from 40 studies. The median age was 72 years (range 42-86 years). The median time to cutaneous toxicity was 4 months (range 0.7-28 months), and the median time to bullae formation was 7.35 months (range 0.7-32 months). The most common clinical features were tense bullae and blisters (85.11%), pruritus (72.34%), and erythema (63.83%) on the limbs and trunk. In 20 of the 22 cases tested, the serum anti-BP180 autoantibodies were positive. However, in 10 cases (91.90%, 10/11) the circulating autoantibodies of anti-BP230 were negative. 40 patients had skin biopsies and the skin biopsy revealed subepidermal bullae or blister eosinophil infiltration in 75.00% of patients with pembrolizumab-induced BP, 10.00% of patients with lymphocyte infiltration and 20.00% of patients with neutrophil infiltration. There were 20 patients (50%) with eosinophilic infiltration around the superficial dermis vessels, 8 patients (20.00%) with lymphocyte infiltration around the superficial dermis vessels, and 4 patients (10.00%) with neutrophil infiltration around the superficial dermis vessels. Direct immunofluorescence detected linear immunoglobulin G (IgG) IgG and/or complement C3 along the dermo-epidermal junction in 36 patients (94.74%) with BP. IgG positivity was detected by indirect immunofluorescence in 81.82% of patients with BP. All patients were in complete remission (95.65%,44/46) or partial remission (4.35%, 2/46) of BP, whereas 9/46 patients had a relapse or refractory. The majority of patients achieved BP remission after discontinuation of pembrolizumab with a combination of topically and systemically administered steroid treatments, or other medications. The median duration of BP remission was 2 months (range 0.3-15 months).

Conclusion

A thorough diagnosis of pembrolizumab-induced BP should be made using clinical signs, biochemical markers, histopathological and immunopathological tests. Pembrolizumab-induced BP had similar clinical characteristics to classic BP. Temporary or permanent discontinuation of pembrolizumab therapy may be required in patients with perbolizumab-induced BP depending on the severity of BP and the response to medication. Pembrolizumab-induced BP may be effectively treated using topical and systemic steroid treatments in combination with other medications (e.g., doxycycline, niacinamide, dapsone, rituximab, intravenous immunoglobulins, dupilumab, cyclophosphamide, methotrexate, mycophenolate mofetil, and infliximab). Clinicians should provide better management to patients with BP receiving pembrolizumab to prevent progression and ensure continuous cancer treatment.

Checkpoint inhibitor-associated bullous cutaneous immune-related adverse events: a multicentre observational study

BACKGROUND

Checkpoint inhibitor (CPI) therapy has significantly improved overall survival in several cancers including metastatic melanoma (MM) and in the adjuvant setting. Cutaneous immune-related adverse events (irAEs) secondary to CPIs are commonly observed; however, autoimmune blistering disorders such as bullous pemphigoid (BP) are rare.

OBJECTIVES

To review the prevalence, incidence risk, clinicopathological features and management of toxicity in bullous cutaneous irAEs associated with CPI therapy.

METHODS

A multicentre, retrospective, observational study of CPI-associated bullous irAEs in adults with all cancers across four UK specialist centres between 2006 and 2019.

RESULTS

In total, 7391 patients were identified. CPI-associated bullous irAEs including BP (n = 16) occurred in 0·3% (n = 22). The median age of onset was 76 years, and there was a male predominance. Most patients had cutaneous melanoma (73%, n = 16), of which 81% (13 of 16) were BRAF wildtype. Grade 1, 2, 3 and 4 skin toxicity occurred in 9%, 45%, 41% and 5%, respectively. The mucosae were involved in 27%, and 25% of confirmed cases of BP did not present with bullae. The median time to onset of bullous irAEs was 12 months, with a median total symptom duration of 6 months. Single PD-1/PD-L1 agents had a longer time to onset of symptoms than combination therapy (median 12 vs. 7 months, respectively). Overall, 91%, 64% and 9% of patients required one, two or three lines of treatment, respectively. Two cases occurred after completion of CPIs (1 and 3 months). Of the 20 cases that presented while on CPIs this was permanently discontinued in 55% (11 of 20) and temporarily held in 20% (four of 20). In the four held cases of CPI, bullous eruption reflared in 50%.

CONCLUSIONS

CPI-associated bullous skin toxicity is a rare cutaneous irAE occurring in approximately 0·3% of cases over 13 years of treated patients in this series. Not all cases are diagnostic of BP, but management remains the same. There is a prolonged latency of onset compared with other cutaneous irAEs, with a median time of 12 months, and they can occur after cessation of therapy. Discontinuation of CPIs may be required. Recognizing bullous irAEs promptly and referral to dermatology are essential to optimize management and improve patient outcomes and tumour responses. What is already known about this topic? Checkpoint inhibitor (CPI)-associated bullous pemphigoid is a rare dermatological immune-related adverse event (irAE) that has been reported in small case series and reports. What does this study add? This is the largest multicentre, observational study conducted in the UK over the longest period of 13 years, which demonstrates an overall incidence of bullous cutaneous irAEs secondary to CPIs of 0·3%. Clinical presentation is variable, with one-quarter of patients with bullous pemphigoid presenting without bullae, and mucosal involvement was noted in 27%. Prolonged pruritus is frequently a prodromal symptom. The median time to diagnosis is 12 months and irAEs rarely present after cessation of treatment. Time to onset of symptoms is longer with a single CPI, but with a shorter duration of symptoms compared with combination CPI therapy. Most patients had cutaneous melanoma, of which 81% were BRAF wildtype.

Type XVII collagen: Relevance of distinct epitopes, complement-independent effects, and association with neurological disorders in pemphigoid disorders

Pemphigoid diseases (PD) are autoimmune skin blistering diseases characterized by autoantibodies directed against proteins of the cutaneous basement membrane zone (BMZ). One of the major antigens is type XVII collagen (BP180), a transmembrane glycoprotein, which is targeted in four PDs: bullous pemphigoid, mucous membrane pemphigoid, linear IgA dermatosis, and pemphigoid gestationis. To date, different epitopes on BP180 have been described to be recognized by PD disease patients’ autoantibodies. Different BP180 epitopes were associated with distinct clinical phenotypes while the underlying mechanisms are not yet fully understood. So far, the main effects of anti-BP180 reactivity are mediated by Fcγ-receptors on immune cells. More precisely, the autoantibody–antigen interaction leads to activation of complement at the BMZ and infiltration of immune cells into the upper dermis and, by the release of specific enzymes and reactive oxygen species, to the degradation of BP180 and other BMZ components, finally manifesting as blisters and erosions. On the other hand, inflammatory responses independent of Fcγ-receptors have also been reported, including the release of proinflammatory cytokines and internalization and depletion of BP180. Autoantibodies against BP180 can also be found in patients with neurological diseases. The assumption that the clinical expression of PD depends on epitope specificity in addition to target antigens, autoantibody isotypes, and antibody glycosylation is supported by the observation that epitopes of PD patients differ from those of PD patients. The aim of the present review is to describe the fine specificities of anti-BP180 autoantibodies in different PDs and highlight the associated clinical differences. Furthermore, the direct effects after binding of the autoantibodies to their target are summarized.

Blasenbildende Autoimmundermatosen – Klinik, Diagnostik und neue Therapieansätze

Diese Arbeit gibt eine Übersicht über die Gruppe blasenbildender Autoimmundermatosen und stellt deren wichtigste Vertreter, das bullöse Pemphigoid, den Pemphigus vulgaris sowie den Pemphigus foliaceus, vor. Die häufigste der insgesamt seltenen blasenbildenden Autoimmundermatosen ist das bullöse Pemphigoid (BP). Es betrifft vor allem Patienten jenseits des 60. Lebensjahrs. Charakterisiert ist es typischerweise durch das Auftreten praller Blasen, die mit einem heftigen Juckreiz einhergehen. Ein längeres, sogenanntes prämonitorisches Stadium ohne Blasenbildung ist nicht ungewöhnlich. Es gibt außerdem Varianten mit anderem Erscheinungsbild wie das lokalisierte BP. Der diagnostische Goldstandard ist die direkte Immunfluoreszenzmikroskopie einer periläsional entnommenen Hautbiopsie, welche lineare Ablagerungen von IgG und C3 an der Basalmembran zeigt. Vervollständigt wird die Diagnostik durch die indirekte Immunfluoreszenzmikroskopie sowie weiterführende ELISA-Untersuchungen, mittels derer zirkulierende Autoantikörper im Patientenserum nachgewiesen werden können. Das wichtigste Zielantigen ist BP180, ein hemidesmosomales, von Keratinozyten exprimiertes Protein. Ergänzend kann eine histopathologische Untersuchung erfolgen, die allerdings nur Hinweise zur Spaltebene und zum (meist Eosinophilen-dominierten) Infiltratmuster geben kann und alleine nicht zur Diagnosestellung ausreicht. Die Pathogenese des BP ist Gegenstand der wissenschaftlichen Diskussion. Medikamente wie Dipeptidylpeptidase-4-Inhibitoren können Auslöser sein; Assoziationen zu neurologischen Erkrankungen finden sich häufig. Entsprechend aktueller Leitlinien wird das BP mit topischen bzw. systemischen Glukokortikoiden ggf. in Kombination mit Doxyzyklin, Dapson oder einem Immunsuppressivum behandelt. Bei Therapieresistenz werden intravenöse Immunglobuline oder der anti-CD-20-Antikörper Rituximab eingesetzt. Aufgrund einer vergleichsweise hohen Mortalität bedingt durch Patientenalter und iatrogener Immunsuppression werden neue Therapieansätze gesucht. Fallserien, Kohortenanalysen und Phase 1-/2-Studien mit anti-IgE-Antikörpern und Inhibitoren der eosinophilen Granulozyten sowie des Komplementsystems zeigen teils vielversprechende Effekte. Die wichtigsten Vertreter der Pemphiguserkrankungen sind der Pemphigus vulgaris (PV), der Pemphigus foliaceus (PF) und der sehr seltene paraneoplastische Pemphigus (PNP). Klinisch präsentiert sich der PV mit meist enoralen Schleimhauterosionen und teilweise zusätzlichen Erosionen an der freien Haut. Der PF manifestiert sich nur an der freien Haut. Wie beim BP wird die Diagnose mittels direkter Immunfluoreszenzmikroskopie gestellt, welche beim PV und PF netzförmige Ablagerungen von IgG und C3 innerhalb der Epidermis zeigt. Die häufigsten Zielantigene sind die Desmogleine 1 und 3. Genetische Prädispositionen für den PV und PF sind bekannt und Grund für eine global unterschiedliche Häufigkeit. Der PNP ist immer mit einer malignen Erkrankung assoziiert und von einem progredienten Verlauf mit hoher Mortalität geprägt. Therapeutisch erfordern die Pemphiguserkankungen oft aggressivere Ansätze als das BP. Neben systemischen Glukokortikoiden und Immunsuppressiva wird für den PV und PF der anti-CD-20-Antikörper Rituximab empfohlen. Neue Therapieansätze sind die Hemmung der Bruton-Tyrosinkinase sowie des neonatalen Fc-Rezeptors (FcRN). In einer Phase 2-Studie zeigte Efgartigimod, ein Antagonist des FcRN, eine hohe Therapieeffektivität für Patienten mit PV und PF.

Improving Care in Eosinophil-Associated Diseases: A Charter

Eosinophil-associated diseases (EADs) are a range of heterogeneous conditions in which eosinophils are believed to play a critical pathological role. EADs include common illnesses such as eosinophilic asthma and chronic rhinosinusitis and rare conditions such as hypereosinophilic syndromes (HES) and eosinophilic gastrointestinal disorders (EGIDs). EADs are associated with substantial burdens for the patient, including chronic, debilitating symptoms, increased financial burden, decreased health-related quality of life, and the need for repeated visits to multiple different healthcare professionals (HCPs), emergency departments, and/or hospitals. Poor EAD recognition by HCPs often contributes to delayed diagnoses, which further delays patient access to appropriate care and effective treatments, contributing to poor health outcomes. The objective of this charter is to outline key patient rights and expectations with respect to the management of their condition(s) and to set forth an ambitious action plan to improve health outcomes for patients with EADs: (1) people with EADs, their caretakers, HCPs, and the public must have greater awareness and education about EADs; (2) people with EADs must receive a timely, accurate diagnosis; (3) all people with EADs must have access to an appropriate multidisciplinary team, when necessary; and (4) people with EADs must have access to safe and effective treatment options without unnecessary regulatory delays. The principles described in this charter demonstrate the core elements of quality care that people with EADs must receive, and they represent clear steps by which to reduce patient and caregiver burden and improve patient outcomes. We urge HCPs, healthcare systems, and policymakers worldwide to swiftly adopt these principles to ensure patients with EADs have an accurate diagnosis in a timely manner and access to high-level care and treatment in an appropriate setting.

Clinical Effectiveness and Safety of Initial Combination Therapy with Corticosteroids and Rituximab in Bullous Pemphigoid: A Retrospective Cohort Study

BACKGROUND

Rituximab is a potential initial adjuvant therapy for bullous pemphigoid, yet clinical experience is scarce.

OBJECTIVE

We aimed to examine the clinical outcomes and safety of initial combination therapy with systemic corticosteroids and adjuvant rituximab for the treatment of bullous pemphigoid.

METHODS

A retrospective cohort study was performed on 84 patients with bullous pemphigoid, who received systemic corticosteroids with or without initial adjuvant rituximab therapy (defined as rituximab use within 12 weeks after initiation of systemic corticosteroids).

RESULTS

Among the 84 patients included (37 received systemic corticosteroids with rituximab and 47 were treated with systemic corticosteroids without rituximab), the median time to complete remission on minimal therapy or off therapy was 215 days (95% confidence interval 176.9-253.1) in patients receiving rituximab vs 529 days (95% confidence interval 338.6-719.4) in those not receiving rituximab. A Cox regression analysis showed an increased probability of reaching complete remission on minimal therapy or off therapy with the combined therapy (hazard ratio = 2.28 [1.28-4.07], p = 0.005) after age, Bullous Pemphigoid Disease Activity Index score, and underlying diseases were controlled. In multivariate logistic/linear regressions, initial adjuvant rituximab therapy was associated with a higher complete remission rate (odds ratio = 6.63 [2.09-21.03]) and lower cumulative prednisolone (mg)/body weight (kg) (B = -24.86 [-44.06 to -8.29]) within 48 weeks. Risk of hospitalization for infection was not elevated in the group treated with adjuvant rituximab.

CONCLUSIONS

Rituximab use as adjuvant therapy within 12 weeks after initiation of systemic corticosteroids was associated with a faster and higher rate of achieving complete remission on minimal therapy or off therapy, as well as a significant corticosteroid-sparing effect and a comparable safety profile in this retrospective study. Hence, initial combination therapy with corticosteroids and adjuvant rituximab could serve as an effective treatment option for bullous pemphigoid, but this requires confirmation in randomized controlled studies.

A blistering eruption of the head and neck in an 18-year-old

An 18-year-old presented with an atypical blistering eruption. Direct immunofluorescence microscopy of perilesional skin showed strong linear deposition of IgG and C3 at the dermoepidermal junction. Her presentation was unusual and posed a diagnostic challenge, as this condition is very rare in this age group.

Bullous pemphigoid: Its incidence, mortality and clinical outcome in New Zealand

BACKGROUND/OBJECTIVES

Bullous pemphigoid (BP) is an uncommon autoimmune bullous disorder, with significant morbidity and mortality. Mortality may be as high as 23.5% in the first year after diagnosis. Clear epidemiologic data across Australasia are lacking.

METHODS

A retrospective, multi-centred cohort study was designed to determine the incidence and mortality of bullous pemphigoid in New Zealand. Data from all histopathologically diagnosed patients with bullous pemphigoid between 2009 and 2015 from the Auckland region were obtained. Demographics, clinical characteristics and outcome 3 years from diagnosis (until 31 December 2018) were collected. Demographic data were compared against a denominator year-matched New Zealand Census population.

RESULTS

One hundred sixty-one patients had confirmed bullous pemphigoid, with an incidence rate of 3.03/100 000 person-years [95% CI 2.58-3.54]; 70% were of European ethnicity; 12.4% were Pacific peoples; 11.2% were Asian; and 6.8% were Māori. 45.3% had associated cognitive impairment and/or stroke. In the 3-year follow-up, 25% had treatment complications mostly from prednisone therapy. The mortality rate was 40%, highest in the first year of diagnosis, with age at diagnosis a predictor.

CONCLUSION

The incidence and mortality rates are comparable to the UK/Northern Europe. Knowledge of the epidemiology of bullous pemphigoid in New Zealand and within an international settling informs the provision of future care and treatments.

Global Incidence and Prevalence of Bullous Pemphigoid: a Systematic Review and meta-analysis

BACKGROUND

Integrated information on the global prevalence and incidence of bullous pemphigoid (BP) is lacking.

OBJECTIVE

To estimate the incidence and prevalence of BP in a systematic review and meta-analysis.

METHODS

Observational studies were included by using databases of Medline, EMBASE and Cochrane Library. Subgroup analysis was by continent, age, sex and country income level. Random-effects model was used. Between-study heterogeneity was assessed using the I² statistic.

RESULTS

The global incidence was 0.0419 per 1000 person-years (95% CI: 0.0414-0.0424). The incidence was 0.047 per 1000 person-years (95% CI: 0.0462-0.0477), 0.0419 per 1000 person-years (95% CI: 0.0411-0.0426), 0.0072 per 1000 person-years (95% CI: 0.0067-0.0078), 0.003 per 1000 person-years (95% CI: 0.0023-0.0039) in North America, Europe, Asia and Africa, respectively; 0.0202 per 1000 person-years (95% CI: 0.0196; 0.0208) and 0.0181 per 1000 person-years (95% CI: 0.0175; 0.0188) females and males; 0.001 per 1000 person-years (95% CI: 0.001-0.001), 0.002 per 1000 person-years (95% CI:0.001-0.002), 0.004 per 1000 person-years (95% CI: 0.004-0.004); 0.007 per 1000 person-years (95% CI: 0.007-0.008), 0.011 per 1000 person-years (95% CI: 0.011-0.012), 0.017 per 1000 person-years (95% CI: 0.015-0.018) for age < 50, 50-59, 60-69, 70-79, 80-89 and ≥90 years. 0.0038 per 1000 person-years (95% CI:0.0036-0.004112) (I2 = 99%, p<.05) and 0.0456 per 1000 person-years (95% CI:0.0450-0.0462) (I2 = 100%, p<.05). The pooled clinic-based prevalence was 0.79 % (95% CI: 0.75%-0.84%), and 1.13% (95% CI: 1.06%-1.21%), 0.21% (95% CI: 0.17%-0.26%), 0.13% (95% CI:0.1%-0.15%) for Asia, Africa and Europe.

CONCLUSIONS

This study identified the global incidence and prevalence of BP in terms of spatial and population distributions and among various income level. A relatively higher incidence was in Europe, females, older people and high-income level country. The prevalence was higher in Asia. These findings should be interpreted with caution due to high heterogeneity of included studies.

Long-term oral prednisolone exposure in primary care for bullous pemphigoid: population-based study

BACKGROUND

Oral prednisolone is the mainstay treatment for bullous pemphigoid, an autoimmune blistering skin disorder affecting older people. Treatment with moderate-to-high doses is often initiated in secondary care, but then continued in primary care.

AIM

To describe long-term oral prednisolone prescribing in UK primary care for adults with bullous pemphigoid from 1998 to 2017.

DESIGN AND SETTING

A prospective cohort study using routinely collected data from the Clinical Practice Research Datalink, a primary care database containing the healthcare records for over 17 million people in the UK.

METHOD

Oral prednisolone exposure was characterised in terms of the proportion of individuals with incident bullous pemphigoid prescribed oral prednisolone following their diagnosis, and the duration and dose of prednisolone.

RESULTS

In total, 2312 (69.6%) of 3322 people with bullous pemphigoid were prescribed oral prednisolone in primary care. The median duration of exposure was 10.6 months (interquartile range [IQR] 3.4-24.0). Of prednisolone users, 71.5% were continuously exposed for >3 months, 39.7% for >1 year, 14.7% for >3 years, 5.0% for >5 years, and 1.7% for >10 years. The median cumulative dose was 2974 mg (IQR 1059-6456). Maximum daily doses were ≥10 mg/day in 74.4% of prednisolone users, ≥20 mg/day in 40.7%, ≥30 mg/day in 18.2%, ≥40 mg/day in 6.6%, ≥50 mg/day in 3.8%, and ≥60 mg/day in 1.9%.

CONCLUSION

A high proportion of people with incident bullous pemphigoid are treated with oral prednisolone in UK primary care. Action is required by primary and second care services to encourage use of steroid-sparing alternatives and, where switching is not possible, ensure prophylactic treatments and proactive monitoring of potential side effects are in place.

Drug eruptions with novel targeted therapies - immune checkpoint and EGFR inhibitors

Given the increasing use of novel targeted therapies, dermatologists are constantly confronted with novel cutaneous side effects of these agents. A rapid diagnosis and appropriate management of these side effects are crucial to prevent impairment of the patients' quality of life and interruptions of essential cancer treatments. Immune checkpoint and EGFR inhibitors are frequently used targeted therapies for various malignancies and are associated with a distinct spectrum of cutaneous adverse events. Exanthematous drug eruptions represent a particular diagnostic challenge in these patients. Immune checkpoint inhibitors can elicit a plethora of immune-related exanthemas, most commonly maculopapular, lichenoid, and psoriasiform eruptions. Additionally, autoimmune bullous dermatoses and exanthemas associated with connective tissue diseases may arise. In cases of severe, atypical or therapy-resistant presentations an extensive dermatological investigation including a skin biopsy is recommended. Topical and systemic steroids are the mainstay of treatment. Papulopustular eruptions represent the major cutaneous adverse effect of EGFR inhibitor therapy, occurring in up to 90 % of patients within the first two weeks of therapy, depending on the agent. Besides topical antibiotics and steroids, oral tetracyclines are the first choice in systemic treatment and can also be used as prophylaxis.

Hospital Admission Trends Due to Viral Infections Characterised by Skin and Mucous Membrane Lesions in the Past Two Decades in England and Wales: An Ecological Study

Objectives: This study aimed to investigate the trends in hospital admissions due to viral infections characterized by skin and mucous membrane lesions in England and Wales between 1999 and 2019. Methods: This is an ecological study using publicly available databases in England and Wales; the Hospital Episode Statistics database in England and the Patient Episode Database for Wales. Hospital admissions data were collected for the period between April 1999 and March 2019. Hospital admissions due to viral infections characterized by skin and mucous membrane lesions were identified using the tenth version of the International Statistical Classification of Diseases system, diagnostic codes B00–B09. The trend in hospital admissions was assessed using a Poisson model. Results: Hospital admissions for different causes increased by 51.9% (from 25.67 (95% CI 25.23–26.10) in 1999 to 38.98 (95% CI 38.48–39.48) in 2019 per 100,000 persons, trend test, p < 0.01). The most prevalent viral infections characterized by skin and mucous membrane lesions hospital admissions causes were zoster (herpes zoster), varicella (chickenpox), herpesviral (herpes simplex) infections, and viral warts, which accounted for 26.9%, 23.4%, 18.7%, and 17.6%, respectively. The age group below 15 years accounted for 43.2% of the total number of admissions. Females contributed to 50.5% of the total number of admissions. Hospital admission rate in males increased by 61.1% (from 25.21 (95% CI 24.59–25.82) in 1999 to 40.60 (95% CI 39.87–41.32) in 2019 per 100,000 persons). The increase in females was 43.2% (from 26.11 (95% CI 25.49–26.72) in 1999 to 37.40 (95% CI 36.70–38.09) in 2019 per 100,000 persons). Conclusion: Our study demonstrates an evident variation in hospital admission of viral infections characterized by skin and mucous membrane lesions based on age and gender. Efforts should be directed towards vaccinating high-risk groups, particularly the elderly and females. Moreover, efforts should be focused on vaccinating the young population against varicella, particularly females who are more susceptible to acquiring the infection. Further observational and epidemiological studies are needed to identify other factors associated with increased hospital admission rates.

DPP-4 Inhibitors and Increased Reporting Odds of Bullous Pemphigoid: A Pharmacovigilance Study of the FDA Adverse Event Reporting System (FAERS) from 2006 to 2020

BACKGROUND

In recent years, an association between dipeptidyl peptidase-4 (DPP-4) inhibitors and bullous pemphigoid has been detected in pharmacovigilance studies in European and Asian countries; however, no pharmacovigilance data have been published yet in the USA.

OBJECTIVE

The objective of this study was to examine the relationship between bullous pemphigoid and DPP-4 inhibitors and other oral diabetes mellitus medications in the FDA Adverse Event Reporting System (FAERS).

METHODS

Case/non-case analyses were performed in the FAERS using data from 2006 to 2020 to examine the reporting odds ratio (ROR) signal for bullous pemphigoid for all classes of oral diabetes medications. These analyses were performed under multiple conditions to control for bias: (1) comparison to all other drugs in the FAERS; (2) comparison to other diabetes medications; and (3) comparison to all other diabetes medications where only a single agent was implicated.

RESULTS

A statistically significant ROR for bullous pemphigoid was found for DPP-4 inhibitors under all conditions: (1) 109.79 (95% confidence interval [CI] 101.61-118.62); (2) 74.46 (95% CI 60.58-91.52); and (3) 35.94 (95% CI 27.91-46.28). A larger signal was seen for non-US Food and Drug Administration (FDA)-approved (anagliptin, vildagliptin, teneligliptin) vs FDA-approved DPP-4 inhibitors (alogliptin, linagliptin, saxagliptin, sitagliptin), likely because of an overestimation of the ROR for non-FDA-approved drugs. The largest signal was seen under conditions 1 and 2 with vildagliptin (1) 1022.83 (95% CI 909.45-1150.35) and (2) 158.84 (95% CI 127.01-198.66) followed by anagliptin (1) 628.63 (95% CI 221.36-1785.24) and (2) 60.64 (95% CI 20.98-175.26), alogliptin, teneligliptin, linagliptin, sitagliptin, and saxagliptin. Under condition 3, the largest signal was seen with linagliptin 122.25 (95% CI 93.96-159.07). Both metformin and the sulfonylureas had a significant ROR under condition 2 [3.42 (95% CI 3.01-3.89) and 2.07 (95% CI 1.66-2.57) respectively]; however, this association was not present under condition 3 as only confounded cases occurred, and a large majority of reported cases had concurrent exposure to a DPP-4 inhibitor.

CONCLUSIONS

Our findings support an association between DPP-4 inhibitors and bullous pemphigoid. This association was maintained under controls to limit bias and falsely elevated signal, including controlling for disease state and cases with multiple drug exposures. Non-FDA-approved DPP-4 inhibitors had a larger ROR compared with FDA-approved DPP-4 inhibitors, likely owing to fewer reported adverse effects overall for non-FDA-approved drugs in FAERS.

A multicentre prospective analysis of the incidence of pemphigoid diseases in Turkey

BACKGROUND

The differentiation between the pemphigoid diseases is essential for treatment and prognosis. In Turkey, data on the incidence of these diseases are insufficient. Our aim in this study is to determine the incidence, demographics and clinical characteristics associated with diseases of the pemphigoid group.

METHODS

We prospectively analysed 295 patients with pemphigoid who visited dermatology clinics of tertiary referral hospitals in 12 different regions of Turkey within a year. The diagnosis was based on clinical, histopathological, direct immunofluorescence (DIF) and serological (multivariant enzyme-linked immunosorbent assay [ELISA], indirect immunofluorescence and mosaic-based BIOCHIP) examinations. Clinical and demographic findings, aetiological factors and concomitant diseases observed in the patients were recorded.

RESULTS

A total of 295 (female/male ratio: 1.7/1) patients with pemphigoid were diagnosed in 1-year period. The overall incidence rate of pemphigoid diseases was found to be 3.55 cases per million-years. The ratio of pemphigoid group diseases to pemphigus group diseases was 1.6. The most common pemphigoid type was bullous pemphigoid (BP, 93.2%). The others were epidermolysis bullosa acquisita (3.1%), pemphigoid gestationis (2.4%), linear IgA disease (1%) and mucous membrane pemphigoid (0.3%). The most common (26.8%) possible trigger of the bullous pemphigoid was gliptin derivative drugs. The most common concomitant diseases with pemphigoid were cardiovascular (27.8%) and neurological diseases (23.7%).

CONCLUSIONS

This study showed that the increased frequency of bullous pemphigoid reversed the pemphigoid/pemphigus ratio in Turkey. Further studies are warranted regarding the reasons for this increase.

A blistering new era for bullous pemphigoid: A scoping review of current therapies, ongoing clinical trials, and future directions

Bullous pemphigoid (BP) is a severe autoimmune blistering skin disorder that primarily causes disease in the older population and is the most prevalent subepidermal variant of the pemphigoid diseases. It manifests as exquisitely pruritic vesiculobullous eruptions and is associated with significant morbidity and mortality. Studies are reporting an increase in prevalence, and, among the elderly, BP is no longer considered to be as rare as previously thought. The pathogenesis involves autoantibodies directed against proteinaceous components of hemidesmosomes, with consequent autoimmune destruction of the dermal-epidermal junction. In recent times, more complex elements of the underlying inflammatory orchestra have been elucidated and are being used to develop targeted immunotherapies. The primary treatment modalities of BP include the use of topical and systemic corticosteroids, certain non-immunosuppressive agents (tetracyclines, nicotinamide, and sulfone), and immunosuppressants (methotrexate, azathioprine, cyclophosphamide, and Mycophenolate). However, in the long term, most of these agents are associated with substantial toxicities while recurrence rates remain high. Such egregious prospects led to significant efforts being directed towards developing newer targeted therapies which work by attenuating specific newly discovered pillars of the inflammatory pathway, and these efforts have garnered hope in providing safer alternatives. Our review focuses on presenting the various therapeutic options that are currently in trial since December 2019, as well as on summarizing presently established treatment guidelines to provide readers with the latest exciting updates.

•

Bullous pemphigoid (BP) is a severe autoimmune blistering skin disorder that primarily causes disease in the older population and is the most prevalent subepidermal variant of the pemphigoid diseases.

•

In recent times, more complex elements of the underlying inflammatory orchestra have been elucidated and are being used to develop targeted immunotherapies.

•

The present review focuses on presenting the various therapeutic options that are currently in trial since December 2019, as well as on summarizing presently established treatment guidelines to provide readers with the latest exciting updates.

The global incidence of bullous pemphigoid: a systematic review and meta-analysis

BACKGROUND

Bullous pemphigoid (BP) is an autoimmune blistering disorder that mainly affects older people. Although the disease is associated with considerable morbidity and mortality, the burden of disease worldwide is unclear.

OBJECTIVES

The study aim is to pool the global incidence of BP and determine whether this varies according to geographic area, age group, setting and study quality.

METHODS

Ovid MEDLINE, Ovid Embase and grey literature were systematically searched on 7 April 2020. Two reviewers independently screened, extracted data and appraised each study's quality using the Joanna Briggs Institute critical appraisal tool. Two domains, indicative of selection and survey bias, were used to identify high-quality studies. The cumulative incidence was standardized to 1 year and pooled in a random-effects meta-analysis. Subgroup and sensitivity analyses were conducted.

RESULTS

Twenty-seven studies were identified, of which 23 provided cumulative incidence and four provided incidence rates. The cumulative incidence of BP was 8·2 [95% confidence interval (CI) 4·8-13.7] per million people whereas the incidence rate was 34·2 (95% CI 19·2-60·7) per million person-years. Of the continents that contributed more than one study, the cumulative incidence was 10·3 (95% CI 5·8-18·2) and 5·6 (95% CI 3·5-9·0) per million people in Europe and Asia, respectively. The incidence was highest in studies including adults only (n = 2), in population-based studies (n = 9) and in more recent years. The cumulative incidence was higher (13·3 per million people, 95% CI 6·0-29·5) when restricting the analysis to higher-quality studies (n = 11). High heterogeneity (I² > 82%) was observed across all pooled estimates.

CONCLUSIONS

The incidence of BP varies globally, is generally low but appears to be increasing over time. The burden of disease is likely to be underestimated.

Bullous Autoimmune Dermatoses–Clinical Features, Diagnostic Evaluation, and Treatment Options

BACKGROUND

Bullous autoimmune dermatoses are a clinically and immunopatho - logically heterogeneous group of diseases, characterized clinically by blisters or erosions of the skin and/or mucous membranes. In Germany, their prevalence is approximately 40 000 cases nationwide, and their incidence approximately 20 new cases per million people per year.

METHODS

This review is based on publications that were retrieved by a selective search of the literature focusing on the current German and European guidelines.

RESULTS

Recent years have seen the publication of guidelines, controlled prospective clinical trials, and multicenter diagnostic studies improving both diagnosis and therapy. Specific monovalent and multivariate serological test systems and pattern analysis of tissue-bound autoantibodies allow identification of the target antigens in 80-90% of patients. This enables the precise classification of disease entities, with implications for treatment selection and disease outcome. In 2019, the anti-CD20 antibody rituximab was approved by the European Medicines Agency for the treatment of moderate and severe pemphigus vulgaris, with an ensuing marked improvement in the care of the affected patients. To treat mild and moderate bullous pemphigoid, topical clobetasol proprionate is recommended, in severe disease, combined with systemic treatment, i.e. usually (a) prednisolone p.o. at an initial dose of 0.5mg/kg/d , (b) an immunomodulant, e.g. dapsone or doxycycline, or (c) prednisolone plus an immunomodulant.

CONCLUSION

The early recognition and precise diagnostic evaluation of bullous autoimmune dermatoses now enables improved, often interdisciplinary treatment, in accordance with the available guidelines. Current research projects are focused on new treatment approaches, an improved understanding of the underlying pathophysiology, and further refinements of diagnostic techniques.

Morphological Spectrum of Vesiculobullous Skin Lesions: An Institutional Perspective

Introduction

A vesiculobullous lesion of the skin encompasses a group of dermatological disorders with protean clinicopathological features. They usually occur as a part of the spectrum of various infectious, inflammatory, drug-induced, genetic, and autoimmune disorders. Therefore, accurate diagnosis of these lesions is essential for appropriate management and to reduce the associated morbidity and mortality. The conventional skin punch biopsy is the mainstay in the diagnosis of dermatological diseases, especially when combined with confirmatory tests, such as direct immunofluorescence (DIF). Our study evaluated the clinicopathological spectrum of vesiculobullous lesions.

Methods

We studied 150 cases of vesiculobullous lesions at the Department of Histopathology, Liaquat National Hospital and Medical College Karachi, Pakistan. Written and informed consent was taken from the patients followed by skin punch procedure in which three biopsies were obtained, which included one biopsy from the lesion and two peri-lesional biopsies. One peri-lesional biopsy was sent in cryomatrix for DIF studies, whereas the other two were sent in formalin to follow the standard tissue-processing protocol.

Results

Our results showed that most patients belonged to the geriatric age group of more than 50 years (44.7%), and 54.7% of the patients were females. Total 74.7% of the patients had generalized lesions, followed by lower limbs (9.3%) and trunk (7.3%) involvement. Most patients were diagnosed with bullous pemphigoid (31.3%), followed by pemphigus vulgaris (27.3%), dermatitis herpetiformis (15.3%), Darier’s disease (14.7%), pemphigus foliaceus (4.7%), epidermolysis bullosa (2%), linear immunoglobulin A dermatosis (2%), paraneoplastic pemphigus (0.7%), and drug reactions (0.7%). DIF studies were applied on 60 cases, out of which complement protein C3c was the most commonly deposited protein (53.3%).

Conclusion

Our study emphasized the diagnostic role of skin punch biopsy in the proper evaluation of vesiculobullous skin lesions. Histopathology is the cornerstone diagnostic tool in this regard, with DIF being a useful adjunct.

Defining dipeptidyl peptidase-4 inhibitors-related bullous pemphigoid: A single-centre retrospective study

BACKGROUND

Many studies have corroborated the association of dipeptidyl peptidase-4 inhibitors (DPP4i) use with bullous pemphigoid (BP). It has been speculated that this drug-induced variant presents with a different clinical spectrum than conventional BP.

OBJECTIVE

To determine the prevalence of DPP4i-induced cases of BP and to evaluate whether gliptin-related BP has specific clinicopathological and immunological features.

METHODS

We conducted a retrospective, observational study of BP cases attended at our centre between January 2000 and June 2020. Epidemiological, clinical, histopathological and laboratory data were collected.

RESULTS

A total of 257 cases of BP were collected; 51 (24.3%) were on treatment with DPP4i. When analysing DPP4i-induced BP cases, generalized BP was the predominant pattern and scalp/mucosal involvement was found in 13 patients. Gliptin-related BP cases were associated to a decrease in the eosinophilic infiltrate (p = 0.000) and both the detection rate and concentration of anti-BP180 IgG were lower (p = 0.004, p = 0.001, respectively) than non-DPP4i cases.

LIMITATIONS

Retrospective, single-centre study.

CONCLUSION

Our large DPP4i-induced BP case series has highlighted that DPP4i-induced BP is characterized by generalized lesions and scalp involvement. Lower titres of anti-BP180 antibodies and a decrease in eosinophils infiltrating into the skin may be distinct features of DPP4i-related BP.

Using electronic health records to inform trial feasibility in a rare autoimmune blistering skin disease in England

Background

Trials of novel agents are required to improve the care of patients with rare diseases, but trial feasibility may be uncertain due to concerns over insufficient patient numbers. We aimed to determine the size of the pool of potential participants in England 2015–2017 for trials in the autoimmune blistering skin disease bullous pemphigoid.

Methods

The size of the pool of potential participants was estimated using routinely collected healthcare data from linked primary care (Clinical Practice Research Datalink; CPRD) and secondary care (Hospital Episode Statistics; HES) databases. Thirteen consultant dermatologists were surveyed to determine the likelihood that a patient would be eligible for a trial based on the presence of cautions or contra-indications to prednisolone use. These criteria were applied to determine how they influenced the potential pool of participants.

Results

Extrapolated to the population of England, we would expect approximately 10,800 (point estimate 10,747; 95% CI 7191 to 17,239) new cases of bullous pemphigoid to be identified in a three-year period. For a future trial involving oral prednisolone (standard care), the application of cautions to its use as exclusion criteria would result in approximately 365 potential participants unlikely to be recruited, a further 5332 could be recruited with caution, and 5104 in whom recruitment is still possible. 11–17% of potential participants may have pre-existing dementia and require an alternative consent process.

Conclusions

Routinely collected electronic health records can be used to inform the feasibility of clinical trials in rare diseases, such as whether recruitment is feasible nationally and how long recruitment might take to meet recruitment targets. Future trials of bullous pemphigoid in England may use the data presented to inform trial design, including eligibility criteria and consent processes for enrolling people with dementia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01212-1.

Autoantibodies Against the Immunodominant Bullous Pemphigoid Epitopes Are Rare in Patients With Dermatitis Herpetiformis and Coeliac Disease

Dermatitis herpetiformis (DH) is an extraintestinal manifestation of coeliac disease (CD). Patients with DH have an elevated risk of development of another autoimmune blistering skin disease, bullous pemphigoid (BP). In this study we investigated whether patients with DH and CD (mean age for both 49 years) have circulating autoantibodies against BP180, the major BP autoantigen. ELISA tests showed that only a few DH (3/46) and CD (2/43) patients had BP180-NC16A IgG autoantibodies. Immunoblotting found that more than half of the DH samples contained IgG autoantibodies against full-length BP180. Epitope mapping with 13 fusion proteins covering the BP180 polypeptide revealed that in DH and CD patients, IgG autoantibodies did not target the NC16A or other epitopes typical of BP but recognized other intracellular and mid-extracellular regions of BP180. None of the analyzed DH and CD patients with either ELISA or immunoblotting positivity had IgG or IgA reactivity against the cutaneous basement membrane in indirect immunofluorescence analysis or skin symptoms characteristic of BP. Although only a minority of middle-aged DH patients had IgG autoantibodies against the immunodominant epitopes of BP180, our results do not exclude the possibility that intermolecular epitope spreading could explain the switch from DH to BP in elderly patients.

Assessment of the Characteristics and Associated Factors of Infectious Complications in Bullous Pemphigoid

Objectives: The clinical outcome of bullous pemphigoid appears worse in patients with infectious complications, and assessment of the prevalence and risk factors of infectious complications could be necessary to plan preventative strategies and to instruct the treatment plans. We sought to determine the risk factors of infection and compare associated factors in inpatients and outpatients with different system infections. Design: This is a single-centered retrospective study on the medical records of 252 patients from 2010 to 2018 at the dermatology department, Peking Union Medical College. Medical profiles of medical history, diagnosis, infectious complications, and treatment plans were analyzed. The associated factors were compared between the subgroups, including inpatients and outpatients, different body sites of infection. Results: Of the total 252 patients with bullous pemphigoid (BP), 81 patients (81/252, 32.1%) had infectious complications. Forty-eight patients died from pulmonary infections (11/48, 22.9%), cardiovascular diseases (6/48, 12.5%), and other diseases. Infections were most frequently found in skin/mucosa (44/252, 17.5%), respiratory system (32/252, 12.7%), and blood (10/252, 4.0%). On multivariate analysis, risk factors of infections in BP were maximal control dose of corticosteroids (OR 2.539, 95% CI 1.456-4.430, p = 0.001), low serum albumin level (OR 2.557, 95% CI 1.283, 5.092, p = 0.007), hospitalization (OR 4.025, 95% CI 2.289, 7.079, p < 0.001), comorbidities including respiratory disease (OR 4.060, 95% CI, 1.861, 8.858, p < 0.001), eye disease (OR 4.431, 95% CI 1.864, 10.532, p < 0.001), and diabetes (OR 2.667, 95% CI 1.437, 4.949, p = 0.002). The rate of infection was significantly higher in inpatients compared to that in outpatients (54.0 vs. 20.6%, p < 0.001), with diverse risk factors. Mucocutaneous infections were associated with a maximal control dose of corticosteroid and other dermatoses. Respiratory infections were related to respiratory disease and old age, and hematologic infection was associated with low serum hemoglobin levels and mucosal involvement of BP. Both of them were associated with mucosal involvement of BP and high titer anti-BP180 antibody. Conclusions: Infectious complications of bullous pemphigoid are common and are associated with mucosal involvement of BP, more comorbidities, the higher dose of corticosteroids, and the lower level of serum albumin.