Bullous pemphigoid of childhood: autoantibodies target the same epitopes within the NC16A domain of BP180 as autoantibodies in bullous pemphigoid of adulthood

Pediatric Autoimmune Bullous Disease: A Literature Review and Update on Management

Pediatric autoimmune bullous disease is a rare group of blistering skin disorders in children that result from autoimmunity against intercellular and basement membrane antigens in the skin and mucous membranes. Most pediatric cases are treated with oral corticosteroids or longer-term immunosuppressants such as azathioprine or mycophenolate mofetil. Immunomodulating drugs such as rituximab are increasingly being considered as options for refractory disease.

Bullous pemphigoid in adolescence, a rare demographic

Bullous pemphigoid is rarely seen in adolescence, and its presentation, clinical course, and treatment can differ to that found in other age groups. We present a case of bullous pemphigoid in a 16-year-old with features of koebnerisation and oral mucosal involvement and provide a brief review of paediatric bullous pemphigoid.

Rare Vesiculopustular Eruptions of the Neonatal Period

Numerous disorders present with vesiculopustular eruptions in the neonatal period, ranging from benign to life-threatening. Accurate and prompt diagnosis is imperative to avoid unnecessary testing and treatment for benign eruptions, while allowing for adequate treatment of potentially fatal disorders. In this review, we highlight several rare blistering diseases of the newborn. A diagnostic approach is outlined to provide clinicians with a framework for approaching a neonate with vesicles, pustules, or ulcers.

Bullous pemphigoid

Bullous pemphigoid is the most frequent autoimmune bullous disease and mainly affects elderly individuals. Increase in incidence rates in the past decades has been attributed to population aging, drug-induced cases and improvement in the diagnosis of the nonbullous presentations of the disease. A dysregulated T cell immune response and synthesis of IgG and IgE autoantibodies against hemidesmosomal proteins (BP180 and BP230) lead to neutrophil chemotaxis and degradation of the basement membrane zone. Bullous pemphigoid classically manifests with tense blisters over urticarial plaques on the trunk and extremities accompanied by intense pruritus. Mucosal involvement is rarely reported. Diagnosis relies on (1) the histopathological evaluation demonstrating eosinophilic spongiosis or a subepidermal detachment with eosinophils; (2) the detection of IgG and/or C3 deposition at the basement membrane zone using direct or indirect immunofluorescence assays; and (3) quantification of circulating autoantibodies against BP180 and/or BP230 using ELISA. Bullous pemphigoid is often associated with multiple comorbidities in elderly individuals, especially neurological disorders and increased thrombotic risk, reaching a 1-year mortality rate of 23%. Treatment has to be tailored according to the patient's clinical conditions and disease severity. High potency topical steroids and systemic steroids are the current mainstay of therapy. Recent randomized controlled studies have demonstrated the benefit and safety of adjuvant treatment with doxycycline, dapsone and immunosuppressants aiming a reduction in the cumulative steroid dose and mortality.

Spectrum of Clinical Responses to Therapies in Infantile Bullous Pemphigoid

Infantile bullous pemphigoid (BP) is a rare autoimmune dermatosis characterized by the presence of antibodies against basal membrane zone proteins. Histologic and immunologic features are similar to those of the adult disease, but its clinical features may vary in children. We report here four cases of infantile BP whose atypical presentation or progression shed new light on the disease.

IgE-mediated mechanisms in bullous pemphigoid and other autoimmune bullous diseases

Autoimmune bullous diseases (AIBDs) are characterized by autoantibodies against structural proteins of the dermal-epidermal junction (in pemphigoid diseases) and the epidermal/ epithelial desmosomes (in pemphigus diseases). By far, the most common AIBD is bullous pemphigoid, which is immunopathologically characterized by autoantibodies against BP180 (type XVII collagen) and BP230. IgG and, to a lesser extent, IgA autoantibodies are the major autoantibody isotypes in these disorders. IgE autoantibodies are increasingly reported in particular in bullous pemphigoid. The development of specific and sensitive anti-BP180 IgE ELISA systems, the report of two experimental murine models employing IgE autoantibodies against BP180, and the successful treatment of bullous pemphigoid with the anti-IgE antibody omalizumab have raised interest in the role of IgE autoantibodies and the modulation of their production in AIBDs. Here, the relevance of IgE autoantibodies in the diagnosis, pathophysiology, and treatment decisions of AIBDs, with a focus on bullous pemphigoid, is reviewed.

Bullous pemphigoid in infants: characteristics, diagnosis and treatment

BACKGROUND

Bullous pemphigoid (BP) in infants is a rare but increasingly reported autoimmune blistering skin disease. Autoantibody reactivity is usually poorly characterized. Current guidelines do not address specific aspects of the infantile form of BP. The objectives of this study are to define clinical and diagnostic characteristics of infantile BP and develop a treatment algorithm.

METHODS

Detailed characterization of a current case series of five infants with BP from our departments. Comprehensive analysis of all reported cases (1-12 months) with respect to clinical and laboratory characteristics, treatment and outcome.

RESULTS

In total 81 cases were identified (including our own). The mean age was 4.5 months. Moderately severe and severe disease was seen in 84% of cases. Involvement of hands and feet was present in all cases. Immunofluorescence microscopy was comparable with BP in adults. Where analyzed, the NC16A domain of bullous pemphigoid 180 kDa antigen/collagen XVII (BP180) was identified as the major target antigen. BP180 NC16A ELISA values in our cohort were significantly higher than in a control cohort of 28 newly diagnosed adult patients. 50% of patients were treated with systemic corticosteroids, 20% with a combination of systemic corticosteroids and dapsone or sulfapyridine and 10% with topical corticosteroids alone. 14% of patients needed a combination of multiple immunosuppressants. All but one patient reached remission. Relapses were rare.

CONCLUSIONS

Presentation of infantile BP is often severe with blistering of hands and feet present in all cases. Pathogenesis and diagnostic criteria are comparable to adult BP, yet BP180 NC16A ELISA levels seem to be significantly higher in infants. The overall disease outcome is favorable. Based on the results of this study we propose a treatment algorithm for infantile BP.

Childhood Bullous Pemphigoid: Report of Three Cases

Bullous pemphigoid (BP) is a disorder that rarely occurs in children. We hereby describe three cases of childhood BP aged 2-4 months, which are among the youngest reported in the literature. BP was confirmed by histopathology, direct and indirect immunofluorescence with salt-split skin test and immunoblotting. These patients were successfully treated with systemic corticosteroids with a complete clinical remission.

Childhood Bullous Pemphigoid Successfully Treated with Diaminodiphenyl Sulfone

Bullous pemphigoid (BP) is an acquired autoimmune blistering disease which predominantly affects the elderly. It is rare in children and infants. We reported a 14-year-old girl presenting with a month history of relapsing tense bullae on the face and extremities. Histopathological examination of the lesional skin revealed a subepidermal bulla with infiltration of eosinophils, neutrophils, and lymphocytes. Direct immunofluorescence showed linear deposits of IgM and C3 at the basement membrane zone. Indirect immunofluorescence using normal human skin sections as a substrate detected IgG anti-basement membrane zone antibodies in the patient's serum and that using 1M NaCl split skin sections showed that the patient's antibodies bound to the epidermal side of the split skin. Immunoblot analysis using normal human epidermal extracts demonstrated the presence of autoantibodies against the 230-kDa BP antigen. Furthermore, the patient's serum reacted with the recombinant protein of the NC16a domain of the 180-kDa BP antigen by immunoblot analysis and enzyme-linked immunosorbent assay. Our patient showed significant improvement of the skin lesions with systemic administration of diaminodiphenyl sulfone.

Molecular diagnosis in autoimmune skin blistering conditions

Blister formation in skin and mucous membranes results from a loss of cell-cell or cell-matrix adhesion and is a common outcome of pathological events in a variety of conditions, including autoimmune and genetic diseases, viral and bacterial infections, or injury by physical and chemical factors. Autoantibodies against structural components maintaining cell-cell and cell-matrix adhesion induce tissue damage in autoimmune blistering diseases. Detection of these autoantibodies either tissue-bound or circulating in serum is essential to diagnose the autoimmune nature of disease. Various immunofluorescence methods as well as molecular immunoassays, including enzyme-linked immunosorbent assay and immunoblotting, belong to the modern diagnostic algorithms for these disorders. There is still a considerable need to increase awareness of the rare autoimmune blistering diseases, which often show a severe, chronic-relapsing course, among physicians and the public. This review article describes the immunopathological features of autoimmune bullous diseases and the molecular immunoassays currently available for their diagnosis and monitoring.

Trauma-associated juvenile bullous pemphigoid in a teenager with Crohn's disease

Bullous pemphigoid is an autoimmune blistering disorder rarely seen in the pediatric population. We report a case of trauma-associated bullous pemphigoid presenting in a 15-year-old boy with Crohn's disease while on immunosuppressive therapy.

Infantile bullous pemphigoid treated with intravenous immunoglobulin therapy

A 3-month-old boy presented with a 2-week history of rapidly spreading skin rashes. Physical examination revealed generalized urticarial plaques with tense bullae and small vesicles. Histologic examination and immunofluorescence established the diagnosis of bullous pemphigoid. The disease was resistant to conventional therapies with the combination of corticosteroids, dapsone, and erythromycin. Finally, intravenous immunoglobulin therapy brought about a remarkable improvement. We suggest that intravenous immunoglobulin therapy is a valuable treatment option for intractable bullous pemphigoid in infants as well as in adults.

Childhood bullous pemphigoid treated by i.v. immunoglobulin

Bullous pemphigoid is an acquired autoimmune subepidermal blistering disorder mostly seen in the elderly. Childhood bullous pemphigoid is very rare. For the first time we report a case of childhood bullous pemphigoid associated with infantile eczema. Two weeks after a routine vaccination, a 3.5-month-old boy with infantile eczema developed a generalized blistering disorder. Histopathology revealed a subepidermal blister. Direct immunofluorescence showed linear depositions of C3 along the basement membrane zone. Indirect immunofluorescence studies demonstrated the presence of circulating immunoglobulin G antibodies directed against the epidermal side of salt-split skin. Enzyme-linked immunosorbent assay demonstrated serum level of anti-BP180 antibody elevated. The patient was successfully treated by high-dose i.v. immunoglobulin.

Métodos diagnósticos en las enfermedades ampollosas subepidérmicas autoinmunes

There is considerable clinical and histological overlap among the subepidermal autoimmune bullous diseases. The knowledge at the molecular level of the dermo-epidermal junction is essential to understand this group of diseases. The immune-based techniques have contributed to increase the knowledge of these entities and have been progressively incorporated into clinical practice. In this review of the diagnostic methods of subepidermal autoimmune bullous diseases we summarize the most recent advances on the molecular biology of the dermo-epidermal junction, focusing on the immune-based diagnostic techniques. We distinguish two main groups of diagnostic methods: those that detect autoimmune deposits in the skin (direct immunofluorescence and its variants including confocal microscopy) and those that detect antibodies in serum or in other fluids (indirect immunofluorescence and its variants, ELISA, immunoblot and immunoprecipitation). We explain the methodology and diagnostic keys of the techniques most widely applied in our milieu.

Absence of anti-BP180 antibodies in mothers of infants with bullous pemphigoid

BACKGROUND

It is not clear whether bullous pemphigoid (BP) of infancy is linked to maternal transmission of pathogenic autoantibodies. Objectives To search for anti-BP180 antibodies in the sera of infants with BP and their mothers, using sensitive and specific methods.

METHODS

Four infants (<6 months) with BP and their mothers were tested for anti-BP180 antibodies by indirect immunofluorescence, immunoblotting and enzyme-linked immunosorbent assay (ELISA).

RESULTS

We found anti-BP180 antibodies in the sera of the four infants with all methods. These antibodies reacted with the extracellular domain NC16A. In the serum of their mothers we found 180 and 160 kDa proteins, each in one case, but indirect immunofluorescence and ELISA were negative, suggesting the absence of anti-BP180 autoantibodies reacting with the extracellular domain NC16A.

CONCLUSIONS

BP of infants is not due to maternofetal transmission of pathogenic autoantibodies. Other hypotheses for the pathophysiology of BP are discussed.

Vesicular pemphigoid in a 16-year-old boy

We describe a case of a 16-year-old African-American boy with bullous pemphigoid (BP), an acquired autoimmune blistering disease that is rarely seen in children. The patient's lesions, however, were distinctly herpetiform, complicating initial diagnosis and therapy. A diagnosis of BP was made by direct and indirect immunofluorescence. Immunoblotting and enzyme-linked immunosorbent assay analysis confirmed the presence of autoantibodies directed against the BP180 antigen. The autoantibodies reacted with the same epitopes within the immunodominant BP180 NC16A domain that have previously been shown to be the target of autoantibodies in BP. This case describes an uncommon disease in the pediatric population and should be included in the differential diagnosis in young patients with an unusual generalized vesicular eruption.

[Blistering autoimmune diseases of childhood]

Autoimmune blistering skin diseases are exceedingly rare in children. In most cases, they are characterized by circulating autoantibodies directed against adhesion structures of the skin which subsequently induce blistering at the dermoepidermal junction or intraepidermally. The most frequent paediatric immunobullous disease is linear IgA dermatosis; all others such as pemphigoid, epidermolysis bullosa acquisita, dermatitis herpetiformis and pemphigus are less common than in adults. In children, mucous membranes are involved more frequently. Recent advances in the identification of the autoantigens have improved diagnostic approach and therapeutic management of blistering diseases. In most cases, treatment requires systemic immunosuppression. With respect to the chronic course of the diseases and potential complications of treatment, cooperation between dermatologists and paediatricians seems advisable.

Oral pemphigoid masquerading as necrotizing ulcerative gingivitis in a child

BACKGROUND

Cicatricial pemphigoid (benign mucous membrane pemphigoid) is an autoimmune vesiculobullous disease that affects mucosal tissues of adults and rarely presents in children. Only 9 cases in the English literature have reported cicatricial pemphigoid in children, primarily as oral mucosal lesions. This paper presents a case of childhood cicatricial pemphigoid that clinically manifested as necrotizing ulcerative gingivitis (NUG).

METHODS

A 9-year-old girl presented with gingival bleeding and discomfort for 2 weeks. NUG was suspected and the patient was treated with antibiotics and an oral hygiene regimen. When the condition did not improve after repeated treatment trials, routine hematoxylin and eosin (H&E) and direct immunofluorescence examinations were performed.

RESULTS

Microscopic examination of H&E stained sections showed a non-specific ulceration with chronic inflammation. Direct immunofluorescence studies of peri-lesional tissue showed linear deposition of C3 at the basement membrane zone that was consistent with a diagnosis of cicatricial pemphigoid.

CONCLUSION

Cicatricial pemphigoid is an autoimmune ulcerative condition that is rarely seen in children. Immunofluorescence studies are essential to differentiate this condition from other ulcerative oral lesions.

Bullous pemphigoid in two young infants

Bullous pemphigoid (BP) usually affects the elderly. The disease is uncommon in children and only a few cases have been described in infants < or =4 months of age. We describe two infants, ages 3 and 4 months, with BP. One infant had a recalcitrant course, and responded only to a combination of high-dose oral corticosteroids and dapsone.

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.