IgA pemphigus occurring in a 1-month-old infant

IgA Pemphigus in a Child – a Case Report

IgA pemphigus (IGAP) is a rare autoimmune bullous disease characterized by IgA deposits on keratinocyte cell surfaces. The IGAP is classified into: 1) subcorneal pustular dermatosis (SPD) type, and 2) intraepidermal neutrophilic (IEN) IgA dermatosis type. So far, only 9 children with IGAP have been described in the literature, of whom only 3 with SPD type. We report a 3-year-old boy with SPD type of IGAP. Clinically, he presented with pruritic vesicles, pustules and erosions on the face, trunk, groin area, and extremities. Histopathology showed subcorneal pustules containing a few acantholytic cells. Direct immunofluorescence (DIF) test of Tzanck smear showed intercellular IgA deposits on the surface of the groups of epidermal cells. Oral dapsone and prednisone induced remission after two weeks; the treatment was discontinued 11 months later, and complete remission was achieved during 19 months without any treatment. Direct immunofluorescence of Tzanck smear is a simple, sensitive, rapid and non-aggressive test, very suitable for the diagnosis of IGAP in children.

Two Brazilian Cases of IgA Pemphigus

IgA pemphigus is a rare, neutrophilic, acantholytic skin disorder with approximately 70 cases described in the literature. We report two patients with the subcorneal pustular dermatosis (SPD) type of IgA pemphigus. Initially, both patients were misdiagnosed as subcorneal pustular dermatosis of Sneddon and Wilkinson. The correct diagnosis was only made after detecting intercellular IgA depositions in the epidermis by direct immunofluorescence. Immunoblotting (IB) of normal human epidermal extracts, performed on both sera, was negative for Dsg 1, Dsg 3, BP 230, BP 180, 210 kDa envoplakin, and 190 kDa periplakin. ELISA for desmogleins (Dsg 1 and Dsg 3) showed that neither of the cases had IgA antibodies to Dsg. The c-DNA transfection test for desmocollins (Dsc) revealed that the IgA antibodies of both patients reacted with desmocollin 1. This result supports the hypothesis that the autoantigen in SPD type IgA pemphigus is desmocollin 1.

[Efficacy of acitretin in IgA pemphigus]

BACKGROUND

IgA pemphigus is a particular entity among autoimmune blistering intraepidermal diseases. IgA pemphigus is subdivided into two types: intraepidermal neutrophilic IgA dermatosis and subcorneal pustular dermatosis.

PATIENTS AND METHODS

We report the case of an 82-year-old woman with intraepidermal neutrophilic IgA pemphigus associated with IgA gammopathy. The histopathological findings were unusual, with numerous large subcorneal pustules, a few pustules in the stratum spinosum, and basal IgA deposition. A favourable outcome was achieved with acitretin.

DISCUSSION

This observation is significant in that it highlights the difficulty of classification of IgA pemphigus, which is currently based on clinical and histopathological findings. There is currently no therapeutic consensus attitude but simply a set of empirical data.

Current approaches to diagnostics and treatment of IgA pemphigus

The authors describe a case of a rare type of pemphigus - IgA pemphigus. They also discuss issues related to pathogenesis, classification, diagnostics and treatment of the disease.

A unique case of intra-epidermal neutrophilic dermatosis-type IgA pemphigus presenting with subcorneal pustules

BACKGROUND

While subcorneal pustular dermatosis-type IgA pemphigus shows subcorneal pustules, intra-epidermal neutrophilic dermatosis (IEN)-type IgA pemphigus is characterised by pustule formation throughout the entire epidermis.

OBJECTIVE

We analysed an unusual case of IEN-type IgA pemphigus showing subcorneal pustules.

METHODS

Indirect immunofluorescence, immunoblot analysis, auto-antibody-specific ELISAs, and double-labelling immuno-electron microscopy were performed.

RESULTS

IgA antibodies bound to the surface of keratinocytes distributed throughout the epidermis were detected by indirect immunofluorescence. IgA from the patient's serum failed to react with COS-7 cells expressing desmocollins (Dsc) 1, 2 or 3. IgG or IgA antibodies against desmogleins 1 and 3 were also found to be absent by ELISA. Double-labelling immuno-electron microscopy using an anti-Dsc monoclonal antibody showed localisation in the desmosomes, while IgA from the patient's serum was found in non-desmosomal regions.

CONCLUSION

The patient in the present study most likely suffers from IEN-type IgA pemphigus.

Erfolgreiche Therapie des IgA-Pemphigus vom subkorneal pustul�sen Typ

IgA pemphigus is a rare autoimmune intraepidermal blistering disease characterized by in vivo bound, and circulating IgA autoantibodies that target cell surface components (cadherins) of epidermal keratinocytes. The average age of onset is approximately 50 years. Histological hallmarks of IgA pemphigus are epidermal acantholysis, subcorneal or intraepidermal pustulosis, and neutrophilic infiltration. The main clinical characteristics are erythematous skin lesions with vesiculopustules, erosions, crusts and desquamation, favoring the trunk, groins, auxiliaries, and proximal extremities. The drug of choice for treating IgA pemphigus is diaminodiphenylsulfone. In this case study, we describe a patient who suffered from IgA pemphigus and responded well to diaminodiphenylsulfone.