Bullous pemphigoid and amyotrophic lateral sclerosis: a new clue for understanding the bullous disease?

Strategies to Improve Outcomes of Bullous Pemphigoid: A Comprehensive Review of Clinical Presentations, Diagnosis, and Patients' Assessment

Bullous pemphigoid (BP) is the most frequent autoimmune bullous disease mainly affecting elderlies. Diagnosis usually results from clinical features, histological examination, and the quantification of circulating typical autoantibodies, due to its higher incidence in elderly patients, bullous pemphigoid treatment and management still represents a challenge due to the higher frequency of several comorbidities in this group of patients, which may also be linked to a reduced tolerance to BP treatments. Hence, an early diagnosis and a prompt correct treatment are mandatory to reach better clinical outcomes and improve as much as possible BP outcomes. Herein, we carried out a comprehensive literature review about the known clinical presentations, diagnosis, assessment and monitoring procedures used in daily clinical practice in patients with BP, to better define strategies to improve as much as possible BP clinical outcomes.

Mortality among family members of patients with amyotrophic lateral sclerosis - a Swedish register-based study

Objective: To test two hypotheses: (1) partners of ALS patients have higher mortality due to outcomes related to psychological distress, and (2) parents and siblings of ALS patients have higher mortality due to diseases that co-occur with ALS.Methods: We performed a nationwide, register-based cohort study in Sweden. We included ALS-free partners, biological parents and full siblings (N = 11,704) of ALS patients, as well as ALS-free partners, biological parents and full siblings (N = 14,460,150) of ALS-free individuals, and followed them during 1961-2013. Hazard ratios (HRs) and 95% confidence intervals (CIs) of overall and cause-specific mortality were derived from Cox regression.Results: Partners of ALS patients, compared to partners of ALS-free individuals, displayed higher mortality due to external causes (HR 2.14; 95% CI 1.35-3.41), including suicide (HR 2.44; 95% CI 1.09-5.44) and accidents (HR 2.09; 95% CI 1.12-3.90), after diagnosis of the ALS patients. Parents of ALS patients had a slightly higher overall mortality (HR 1.03; 95% CI 1.00-1.07), compared with parents of ALS-free individuals. This was driven by mortality due to dementias and cardiovascular, respiratory, and skin diseases. Parents of ALS patients had, however, lower mortality than parents of ALS-free individuals due to neoplasms. Siblings of ALS patients had higher mortality due to dementias, and digestive and skin diseases.Conclusions: Increased mortality due to suicide and accidents among partners of ALS patients is likely attributable to severe psychological distress following the ALS diagnosis. Increased mortality due to dementias among parents and full siblings of ALS patients suggests shared mechanisms between neurodegenerative diseases.

Young-onset Amyotrophic Lateral Sclerosis with Rare Skin Manifestation: Case Report and Literature Review

Amyotrophic lateral sclerosis (ALS) is one of the most common motor neuron diseases (MND), which presents as muscle weakness, atrophy, spasticity, and, in extreme cases, may result in death due to respiratory failure. ALS has been reported with dermatological conditions such as bullous pemphigoid and decreased collagen. Hyperpigmentation usually occurs due to underlying adrenal or metabolic disorder, but no case of hyperpigmentation has been associated with MND. We report a case of a 25-year-old man who presented with signs of young-onset ALS (progressive weakness of both upper limbs) with hyperpigmentation of limbs. The patient did not have any other underlying etiology, which could have led to the development of hyperpigmentation Biopsy was negative for polymyositis and dermatomyositis. The patient was counseled about the nature of the disease and was advised regular follow-ups.

Bullous Pemphigoid: A Review of its Diagnosis, Associations and Treatment

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease in Western countries, and typically affects the elderly. BP is immunologically characterized by tissue-bound and circulating autoantibodies directed against either the BP antigen 180 (BP180, or BPAG2) or the BP antigen 230 (BP230, or BPAG1e), or even both, which are components of hemidesmosomes involved in the dermal-epidermal cohesion. Risk factors for BP include old age, neurologic diseases (dementia, Parkinson's disease, cerebrovascular disease), and some particular drugs, including loop diuretics, spironolactone and neuroleptics. The spectrum of clinical presentations is extremely broad. Clinically, BP is an intensely pruritic erythematous eruption with widespread blister formation. In the early stages, or in atypical, non-bullous variants of the disease, only excoriated, eczematous or urticarial lesions (either localized or generalized) are present. The diagnosis of BP relies on immunopathologic findings, especially based on both direct and indirect immunofluorescence microscopy observations, as well as on anti-BP180/BP230 enzyme-linked immunosorbent assays (ELISAs). BP is usually a chronic disease, with spontaneous exacerbations and remissions, which may be accompanied by significant morbidity. In the past decade, potent topical corticosteroids have emerged as an effective and safe first-line treatment for BP, but their long-term feasibility is still controversial. Newer therapeutic agents targeting molecules involved in the inflammatory cascade associated with BP represent future alternatives to classical immunosuppressant drugs for maintenance therapy.

Frequency of Neurological Disorders in Bullous Pemphigoid Patients: A Cross-Sectional Study

Background

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering skin disorder which occurs mostly in the elderly. Several studies have reported an association between BP and neurological disorders (ND).

Objective

The purpose of this study was to evaluate the association between BP and neurological disorders in Iranian patients.

Methods

In this cross-sectional study, 87 patients with BP were enrolled. They were compared to 184 controls. Statistical analysis was done by SPSS statistical software version 19.

Results

Out of 87 patients with BP, 17 (19.5%) had at least one neurological disease. Cerebrovascular accident (CVA) was the most common neurological disease that was seen in 7 patients (8.0%) in the case group and 4 (2.1%) in the control group. The incidence of CVA was significantly different between BP patients and the control group (P = 0.022). Dementia was observed in 6 patients in the case group (16.8%) and 2 (1.0%) in the control group. The incidence of dementia was significantly different between BP patients and the control group (P = 0.008). In this study, the incidences of Parkinson's disease (P = 0.830), epilepsy (P = 0.067), and multiple sclerosis (P = 0.326) were not statistically significant between the two groups.

Conclusion

The incidence of CVA and dementia in patients with BP compared to the control group was significantly higher.

Pemphigus vulgaris and amyotrophic lateral sclerosis

Pemphigus vulgaris (PV) is an autoimmune bullous and erosive mucocutaneous disease. Rarely, it occurs in patients with other autoimmune disease. The relation between PV and neurological disorders is unclear and needs to be more studied. Here, we report a case of amyotrophic lateral sclerosis (ALS), followed by dermatologic involvement. Histopathological evidence and direct immunofluorescence are consistent with PV. Systemic corticosteroid and azathioprine were effective in the treatment of mucocutaneous lesions. PV seems to be accidentally associated with ALS. Expression of major histocompatibility complex Class II in autoimmune disease and production of autoantibodies have been proposed to describe the association of PV with ALS.

A Potential Link between Amyotrophic Lateral Sclerosis and Bullous Pemphigoid: Six New Cases and a Systematic Review of the Literature

Objective Bullous pemphigoid in amyotrophic lateral sclerosis (BP-ALS) is rare and poorly understood. We herein assessed the association between ALS and BP using clinical and biological findings. Methods The clinical features of six new BP-ALS cases were described and collated with cases from a systematic literature review. Results Our six cases were combined with three other published cases. The mean disease duration (from ALS onset to the occurrence of BP) was 5.6±3.1 years. All patients had limb-onset ALS. Four of the 9 patients received riluzole, with the use of riluzole ranging from a few days to 3 years. When BP occurred, the status of the ALS patients was paretic and/or bedridden in all cases. BP occurred throughout the body, and we confirmed that the bullous lesions were located not only at the compression site, but also at the anterior part of the chest, abdomen, and limbs. Treatment for BP was successful, as oral prednisone and/or local corticosteroids were effective in 8 cases. Conclusion These six new cases, in combination with previous cases, expand our knowledge of the relationship between dermatological lesions and ALS. The pathogenesis of BP-ALS is poorly understood, however, some immunological aberrance is likely.

Cutaneous Adverse Effects of Neurologic Medications

Life-threatening and benign drug reactions occur frequently in the skin, affecting 8 % of the general population and 2-3 % of all hospitalized patients, emphasizing the need for physicians to effectively recognize and manage patients with drug-induced eruptions. Neurologic medications represent a vast array of drug classes with cutaneous side effects. Approximately 7 % of the United States (US) adult population is affected by adult-onset neurological disorders, reflecting a large number of patients on neurologic drug therapies. This review elucidates the cutaneous reactions associated with medications approved by the US Food and Drug Administration (FDA) to treat the following neurologic pathologies: Alzheimer disease, amyotrophic lateral sclerosis, epilepsy, Huntington disease, migraine, multiple sclerosis, Parkinson disease, and pseudobulbar affect. A search of the literature was performed using the specific FDA-approved drug or drug classes in combination with the terms 'dermatologic,' 'cutaneous,' 'skin,' or 'rash.' Both PubMed and the Cochrane Database of Systematic Reviews were utilized, with side effects ranging from those cited in randomized controlled trials to case reports. It behooves neurologists, dermatologists, and primary care physicians to be aware of the recorded cutaneous adverse reactions and their severity for proper management and potential need to withdraw the offending medication.

[Impact of neurological diseases on the prognosis of bullous pemphigoid: A retrospective study of 178 patients]

BACKGROUND

Bullous pemphigoid (BP) mainly affects elderly patients. It is often associated with neurological disorders, which constitute a major risk factor of the disease. The aim of our study was to determine whether neurological disorders, particularly dementia, influence outcome and mortality in BP patients.

PATIENTS AND METHODS

We conducted a retrospective study of all patients with BP seen in our dermatology department consecutively between 1997 and 2011. Clinical, immunological and therapeutic data, number of relapses and survival status were compared according to the presence at diagnosis of neurological disorders, particularly dementia.

RESULTS

Among the 178 patients included, an associated neurological disease was present in 84 (47.2%) and dementia in 43 (24.2%) at the time of diagnosis of BP. Patients with associated dementia were older and had a lower Karnofsky index. Sixty-four patients (37.8%) had had at least one clinical relapse of BP, chiefly within the first 18 months after starting therapy. Coexistent neurological disease was not associated with BP relapse (P=0.55) contrary to an extensive BP phenotype at diagnosis (P=0.008). Coexistent neurological disease and/or dementia were associated with higher mortality (P=0.03 and P<0.001, respectively), but did not modify the type or the total duration of BP treatment.

CONCLUSION

A coexistent neurological disease or dementia at the time of diagnosis of BP significantly increase the risk of mortality and shortens the duration of clinical follow-up of patients with BP, thus limiting the analysis of their influence on the outcome of BP itself.

A Novel F45S SOD1 Mutation in Amyotrophic Lateral Sclerosis Coexisting with Bullous Pemphigoid

Background

The coexistence of an autoimmune disease and amyotrophic lateral sclerosis (ALS) has led to the hypothesis that immune-mediated pathological mechanisms are overlapping in the two diseases. We report herein a rare coexistence of bullous pemphigoid (BP) in a novel mutation (F45S) of the gene encoding Cu/Zn superoxide dismutase (SOD1) in an ALS patient, and discuss a role for the SOD1 mutation in this unusual overlap.

Case Report

A 57-year-old male with familial ALS, including vesicles and tense bullae on erythematous bases, was diagnosed with BP. Direct immunofluorescence revealed deposits of C3 and immunoglobulin G in the basement membrane zone. Direct sequencing of SOD1 in the patient revealed a novel mutation (c.137T>C; F45S).

Conclusions

We report a novel SOD1 mutation in ALS, which was combined with BP. This novel SOD1 mutation could affect the phenotype of a combined autoimmune disease and matrix metalloproteinase-9. There may therefore be common factors linking BP and ALS with the SOD1 mutation.

Autoimmune bullous diseases associations

The presence of one autoimmune disorder helps lead to the discovery of other autoimmune conditions. It is thought that diseases in which autoimmunity is a feature tend to be associated together more often than one can ascribe to chance. A variety of diseases have been implicated in the onset of intraepidermal and subepidermal autoimmune diseases. The presence of one autoimmune disease should alert the physician to watch for a second immunologic disorder. A list of autoimmune bullous diseases associations includes autoimmune bullous diseases, pemphigus, pemphigoid, epidermolysis bullosa acquisita, dermatitis herpetiformis (Duhring), linear immunoglobulin A disease, and multiple autoimmune syndrome.

Management of bullous pemphigoid with topical steroids in the clinical practice of a single center: outcome at 6 and 12 months

BACKGROUND

The efficacy of topical steroids in bullous pemphigoid (BP) was assessed by prospective therapeutic trials. Systemic corticosteroids and immunosuppressant agents are indicated in situations of failure or relapses.

OBJECTIVES

To report our experience in the management of BP outside therapeutic trials focusing on the outcome of the patients at 6 and 12 months, compliance and follow-up difficulties.

METHODS

Monocenter retrospective study with collection of clinical, therapeutic and follow-up data after 6 and 12 months.

RESULTS

Ninety-six patients, mean age 84 years, 65 females, 54% had neurological impairment. The initial dose of clobetasol propionate was 30 g/day, followed by a progressive decrease. In the first 6 months, 14% were lost to follow-up and 17.7% died; 62% were controlled with topical steroids alone, and 25% had adjunctive systemic treatment. Difficulties of compliance were mentioned in 34.4%, without significant difference between controlled and noncontrolled patients. After 12 months, 23% were lost to follow-up and 27.1% died. The mean duration of the treatment was 11.7 ± 8.4 months. After the stop, 18.9% of patients relapsed within 3 months.

CONCLUSION

We emphasize the frequent recourse to systemic treatments in the first few months, the difficulties of compliance and of follow-up in our day-to-day experience.

Concomitant rheumatoid arthritis and amyotrophic lateral sclerosis: report of two new cases and review of literature

To describe a rare association between rheumatoid arthritis (RA) and amyotrophic lateral sclerosis (ALS). Two new cases of patients with RA who developed amyotrophic lateral sclerosis (ALS), one receiving anti-TNFα agents, were reported. Only other five cases of this rare association have been previously described in literature. The simultaneous presence of the two diseases represents a difficult diagnostic challenge because RA may mimic some musculoskeletal symptoms of ALS. There is no evidence in favor of a common pathophysiologic mechanism, and thus the possibility of a fortuitous association must be raised. A neurotoxic side effect of various drugs for RA treatment could be considered. Casual or causal association remains a difficult choice. The possibility of a coincidental association must be raised but neurologic side effects of TNFα blockers lead to discussion.

Zebrafish type XVII collagen: gene structures, expression profiles, and morpholino "knock-down" phenotypes

The human COL17A1 gene encodes type XVII collagen (also known as the 180-kDa bullous pemphigoid antigen), an integral component of hemidesmosomes, attachment complexes providing integrity to the dermal-epidermal junction. Zebrafish, a useful model system to study skin development, displays fully developed hemidesmosomes at approximately 5 days post-fertilization (dpf). We have identified two COL17A1 orthologues in the zebrafish genome, col17a1a and col17a1b, which are expressed in the skin and the neural system, respectively. The proteins coded by these genes have structural module organizations homologous to the human type XVII collagen. "Knock-down" of the expression of col17a1a with a specific morpholino targeting the 5' UTR of the gene resulted in a blistering phenotype and in perturbations in the basement membrane zone. "Knock-down" of col17a1b expression resulted in ablation or in marked reduction of neuromasts in the lateral line. Thus, zebrafish has two COL17A1 orthologues which may have evolved tissue-specific functions during vertebrate development. Collectively, zebrafish provides a model system to study the molecular aspects of skin development and offers insights into the corresponding human diseases.

Expression of collagen XVII and ubiquitin-binding protein p62 in motor neuron disease

Collagen involvement in motor neuron disease has been suggested by several earlier studies. Recently, we found collagen XVII to be expressed in locations in the human brain that include those damaged in motor neuron disease. In this study, we examined the extent of motor neuron disease-related changes in the brain of 9 subjects using ubiquitin-binding protein p62/sequestosome 1 (p62) immunohistochemistry. We then assessed whether or not the expression of collagen XVII was altered in relation to the p62 immunoreactive lesions. We found that neuronal collagen XVII expression in motor neuron disease remains similar to that seen in the normal human brain and thus a change in collagen XVII expression is not an immunohistochemically detectable feature of motor neuron disease. We also found that the regional distribution of p62 varied according to clinical presentation: p62 immunoreactive inclusions were found in the frontal cortex, hippocampus and cerebellum only in subjects with a history of psychiatric morbidity. Our study supports the re-definition of motor neuron disease as a multisystem disorder with a wide clinicopathological spectrum, and we advocate addressing psychiatric symptomology in future studies of motor neuron disease.

Neurological Disorders in Patients with Bullous Pemphigoid

BACKGROUND

Unexpected cases of bullous pemphigoid (BP) have been reported in adult patients with various neurological disorders suggesting a possible relationship between these diseases.

OBJECTIVES

(1) To determine the prevalence and types of neurological disorders in patients with BP, (2) to assess patients' functional impairment, and (3) to compare the clinical and biological findings as well as prognosis of BP patients presenting with or without neurological disorders.

METHODS

BP patients with neurological disorders were selected in a series of 341 consecutive BP patients treated in 20 French Dermatology Departments. Functional impairment was prospectively assessed using the Karnofsky score which is a measure of patients' general condition.

RESULTS

At least one neurological disorder was present in 123 of the 341 BP patients (36%). They primarily consisted of dementia (n = 68; 20%; 95% CI: 16-25%), cerebral stroke (n = 52; 15%; 95% CI: 4-19%), and/or Parkinson's disease or parkinsonism (n = 32; 9%; 95% CI: 7-13%). BP patients with neurological disease were older than patients without neurological disease (83.8 +/- 7.5 years vs. 79.3 +/- 10.3 years, p < 10(-4)). They also had a lower Karnofsky score (47 +/- 19% vs. 74 +/- 20%, p < 10(-4)). One-year overall survival rates of the two groups were 50.8% (95% CI: 41.8-59.7) and 78.7% (95% CI: 73.0-84.2), respectively (p < 10(-4)). In contrast, the number of bullae and main biological features at baseline were not different between the two groups of patients.

CONCLUSION

This study demonstrated a high frequency of neurological disorders, particularly dementia, in BP patients. Most of these patients had a severe functional impairment and a poor prognosis.

Distribution of collagen XVII in the human brain

We have recently discovered collagen XVII to be present in neurons of the human central nervous system. Collagen XVII has previously been primarily studied in the field of dermatopathology since it is abundantly expressed in the skin, which, like the nervous system, is ectodermal in origin. A link between dermatopathological and neurological entities has been implied due to clinical case studies revealing an association between bullous pemphigoid and age-related neurodegenerative disorders. The objective of this study was to assess the distribution of collagen XVII in the human brain in relation to normal ageing. Post-mortem brain tissue was obtained from 11 neurologically unimpaired subjects who had died from cardiovascular causes at the age of 17 to 78 years. Collagen XVII expression in various neuroanatomical regions, representing essentially the entire human brain, was then assessed using immunohistochemistry. We found collagen XVII to be expressed widely in the brain and to be located primarily in the soma and proximal axons of neurons. In contrast, glial cells did not express collagen XVII. The expression varied strikingly between different neuroanatomical regions, being most notable in motor nuclei and Betz cells followed by pyramidal neurons. There was no correlation between collagen XVII expression and variables such as gender, age at death, post-mortem delay and fixation time whereas a mode of death leading to notable neuronal ischemia depleted the protein expression. Many neurodegenerative disorders display a specific pattern of neuroanatomical involvement, thus the regionally variable expression of collagen XVII offers new prospects for research.

Bullous pemphigoid: physiopathology, clinical features and management

There has been a considerable progress in the understanding of the physiopathology of BP during the past 2 decades. The insights into the humoral and cellular immune response against BP180 and BP230 have increased significantly. Nevertheless, the factors underlying the initiation of the disease leading to a disruption of self-tolerance remain unclear. Clinically, the disease shows protean presentations, and diagnostic delay is common. A practical, relevant, and unresolved question is how to identify patients suffering from BP at an early stage of the disease, when direct immunofluorescence microscopy findings still may be negative. The characterization of markers allowing the differentiation of BP from other pruritic eruptions occurring in the elderly population would be extremely helpful in daily practice. Finally, despite the knowledge that potent topical steroids are efficient in controlling the disease, management of BP sometimes remains difficult and requires systemic therapies. It is hoped that a better knowledge of the regulation of the autoimmune response in BP also will facilitate the design of novel immunomodulatory therapeutic approaches devoid of the severe side effects of current immunosuppressive treatments.

Corrélation entre présence d’anticorps anti-antigène de type 2 de la pemphigoïde et démence chez les sujets âgés sans manifestation clinique de pemphigoïde

BACKGROUND

Pemphigoid is a form of auto-immune bullous dermatosis characterised by the production of antibodies directed against components of hemidesmosomes in the basal membrane. The physiopathological process responsible for unmasking of these antigens is unknown. Pemphigoid is more common in elderly subjects and is most often seen in debilitated subjects. The prevalence of pemphigoid anti-pemphigoid antibodies (anti-PB) is not known in the elderly population presenting no dermatological signs evocative of the disease. We studied the prevalence of anti-PBAg2 antibodies in elderly subjects with no signs of pemphigoid as well as in the correlation between the presence of these antibodies and diagnosis of dementia.

PATIENTS AND METHODS

Elderly subjects (aged over 69 years) with no signs of pemphigoid were recruited consecutively in dermatology and geriatrics departments (138 subjects). Details of concomitant medication were recorded for all subjects and clinical examination was performed with calculation of MMS (Mini Mental Score). The subjects were then divided into two groups based on MMS score. The first group comprised subjects without dementia (MMS > 24) while the second comprised subjects with dementia. Serum anti-PBAg2 antibodies were determined by ELISA and indirect immunofluorescence with confirmation by Western blot. Antinuclear antibodies, used as a control for non-specific immune response, were assayed in all serum samples. The prevalence of these antibodies was compared between the two groups.

RESULTS

The two groups were comparable in terms of age, sex and presence of dermatological diseases (ulcers, bedsores, erysipelas). Each group comprised 69 subjects. The overall presence of anti-PBAg2 antibodies in subjects with no signs are suggestive of pemphigoid was 3.6%. Presence of anti-PBAg2 antibodies was associated with diagnosis of dementia (p=0.04; 0% and 7% in groups 1 and 2, respectively). No correlation was seen between the presence of anti-PBAg2 antibodies and concomitant medication or dermatological disease. The overall prevalence of antinuclear antibodies was 14.5% and the figure was similar between the two groups.

DISCUSSION

The presence of anti-PBAg2 could be associated with the diagnosis of dementia in elderly subjects.

Localized pemphigoid on the soles of both feet

An 80-year-old woman was referred to our hospital with a spontaneously appearing bullous dermatosis limited to the soles of both feet, causing an intense pruritus. She also suffered from Parkinson's disease and depression, and had been treated with levodopa, benserazide, and mirtazapine for several years. On clinical examination, we found several tense and hemorrhagic bullae, with a diameter of up to 3 cm, at both plantar sites and multiple, confluent, dyshidrotic vesicles ( Figs 1 and 2). The rest of the skin, including the mucous membranes and palms, was normal. The first clinical diagnosis was podopompholyx, but histopathologic findings and direct immunofluorescence revealed a diagnosis of bullous pemphigoid, showing subepidermal blisters (Fig. 3) and linear deposits of C3 and immunoglobulin G (IgG). Indirect immunofluorescence was positive, the IgG autoantibodies bound to the epidermal site of salt-split skin, and circulating antibodies against bullous pemphigoid antigens 1 and 2 were found. Because of this typical clinical picture, a diagnosis of dyshidrotic pemphigoid, a localized form of bullous pemphigoid, was made. Under systemic treatment with prednisolone, 40 mg/day, the skin healed completely within 2 weeks. Descriptions of dyshidrotic pemphigoid limited to the soles of both feet are very rare, and the clinical findings might easily lead to a misdiagnosis of podopompholyx.

Pemphigoïde du sujet jeune

INTRODUCTION

Bullous pemphigoid usually affects elderly people. Only a few isolated cases among people younger than 65 years have been reported.

OBJECTIVES

Describe the clinical and biological characteristics of patients younger than 60 years suffering from bullous pemphigoid, compare them with the usual characteristics known among elderly people and search for potential pathological associations.

PATIENTS AND METHODS

Retrospective, national, multicenter study. Clinical, biological and histological characteristics were recorded with a standardised questionnaire as well as treatments and associated pathologies.

RESULTS

Seventy-four cases of bullous pemphigoid diagnosed between June 1970 and March 2002 were analyzed. Mean age at the beginning of the disease was 46 +/- 11.6 years. Further explorations by indirect immunofluorescence of separated skin and/or immuno-electron microscopy and/or immunoblotting were performed for 42 patients (56.8 p. 100). Clinical characteristics among this restricted population were comparable to those found among the 32 other cases. Compared to usual data on bullous pemphigoid in elderly people, we observed a greater proportion of extensive form of disease (75 p. 100), a more frequent head and neck involvement (39.2 p. 100) and an overexpression of anti-BP180 autoantibodies (48 p. 100). Neoplasm was notified for 7 patients (9.5 p. 100), 18 (24.3 p. 100) suffered from a pathology of the basement membrane zone (6 psoriasis, 6 atopic dermatitis and 6 lichen) and 13 from neurological disease, among which 4 were bedridden. Fourty-six patients (62.2 p. 100) received drugs for the long term (mean 2.12 +/- 2.43), 4 patients were treated by PUVAtherapy and 2 by radiotherapy.

DISCUSSION

Our results suggest that bullous pemphigoid among young people is more severe and more active than the usual form in the elderly. This particular form could be the result of a higher expression of anti-BP180 autoantibodies, which are considered as a marker of poor prognosis in this disease. We also found a high frequency of pathological associations and physical treatment, all responsible for damage to the basement membrane zone, which can involve auto-immunization against hemidesmosome components.

Bullous Pemphigoid

Bullous pemphigoid (BP) is a chronic, autoimmune, blistering disease observed primarily in the elderly population. Several clinical variants have been described, including classic (bullous), localised, nodular, vegetating, erythrodermic, erosive, childhood and drug-induced forms. Autoantibodies target the BP230 and BP180 antigens, located in the hemidesmosomal complex of the skin basement membrane zone. Subsequent complement activation recruits chemical and cellular immune mediators to the skin, ultimately resulting in blister formation. Both autoantibodies and complement may be detected by various immunofluorescent, immune electron microscopy and molecular biology techniques. Recent trials suggest that potent topical corticosteroids should be considered as first-line therapy. Tetracycline with or without nicotinamide may benefit a subset of patients with mild BP. Oral corticosteroids should rarely exceed 0.75 mg/kg/day and corticosteroid-sparing agents may be useful for recalcitrant disease.

Transglutaminases in disease

Transglutaminases (TGases) are enzymes that are widely used in many biological systems for generic tissue stabilization purposes. Mutations resulting in lost activity underlie several serious disorders. In addition, new evidence documents that they may also be aberrantly activated in tissues and cells and contribute to a variety of diseases, including neurodegenerative diseases such as Alzheimer's and Huntington's diseases. In these cases, the TGases appear to be a factor in the formation of inappropriate proteinaceous aggregates that may be cytotoxic. In other cases such as celiac disease, however, TGases are involved in the generation of autoantibodies. Further, in diseases such as progressive supranuclear palsy, Huntington's, Alzheimer's and Parkinson's diseases, the aberrant activation of TGases may be caused by oxidative stress and inflammation. This review will examine the role and activation of TGases in a variety of diseases.