IgA pemphigus: a case report and its characteristic clinical features compared with subcorneal pustular dermatosis

Superficial and Bullous Neutrophilic Dermatoses: Sneddon-Wilkinson, IgA Pemphigus, and Bullous Lupus

Sneddon-Wilkinson disease (SWD), IgA pemphigus, and bullous systemic lupus erythematosus (BSLE) are superficial and bullous neutrophilic dermatoses. They are all characterized by sterile neutrophilic infiltrate but differ in the level of skin affected and presence of autoantibodies. Both SWD and IgA pemphigus present with grouped flaccid pustules and have epidermal involvement; it is unclear whether they are distinct or exist on a spectrum of the same disease. IgA pemphigus is distinguished from SWD by positive direct immunofluorescence showing intercellular IgA deposition. BSLE presents with tense bullae, dermal neutrophilic infiltrate, and direct immunofluorescence showing linear IgG deposition along the dermal-epidermal junction.

The expanding spectrum of IgA pemphigus: a case report and review of the literature

IgA pemphigus (IGAP) is a rare, distinct variant of pemphigus, currently classified, depending upon the histological features, immunofluorescence staining pattern and autoantibody profile, into two types: subcorneal pustular dermatosis (SPD) and intraepidermal neutrophilic IgA dermatosis. In a patient with a widespread blistering disease of the skin resembling SPD-type IGAP, we demonstrate the coexistence of IgA reactivity to both epidermal (desmocollins 2 and 3) and basement membrane-associated (BP180) proteins, suggesting the coexistence of atypical IGAP and linear IgA bullous dermatosis, respectively. This case, together with 20 previous reports of atypical IGAP, underscores the limitations of current classification schemes. Therefore, we suggest reclassifying these cases under the general term 'IGAP spectrum'.

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.

Disulone

For 60 years, dapsone has been used as a both antibacterial and anti-inflammatory agent. Dapsone (4,4'-diaminodiphenylsulfone, DDS) continues to be used successfully to treat a wide range of dermatologic disorders, notably those characterized by abnormal neutrophil and eosinophil polynuclear accumulation. A considerable number of other inflammatory as well as bullous dermatoses, of which dermatitis herpetiformis is the best known, have been shown to respond in varying degrees to dapsone, although the indication for the molecule has not been demonstrated in of them all. This article reviews current knowledge on the pharmacokinetics, mechanism of action and side effects of dapsone in dermatology. Despite the lack of controlled studies, the aim of this study is to specify and classify the pathological states in which disulone could be indicated.

The pustular disorders

The pustular disorders constitute a subgroup of the vesiculobullous disorders defined by the presence of eosinophils or neutrophils with prominent accompanying intercellular edema or a canthelysis involving various levels of the epithelium. Herein, we describe the clinical and pathologic attributes of the subcorneal, infectious, neonatal, papulosquamous, drug-induced and miscellaneous pustular conditions.

Juvenile subcorneal pustular dermatosis: a case report

Subcorneal pustular dermatosis is a chronic, relapsing, pustular dermatosis that usually develops in elderly women. It is rarely seen in childhood and adolescence. The hallmark of the disease is formation of a subcorneal pustule detected on histopathologic examination. Herein we present a 13-year-old girl diagnosed with subcorneal pustular dermatosis based on the typical clinical and histologic findings. Direct and indirect immunofluorescence and serum protein electrophoresis had negative results. The patient partially recovered after 5 weeks of treatment consisting of oral dapsone and a topical steroid ointment.

Pemphigus herpetiformis with IgA and IgG antibodies to desmoglein 1 and IgG antibodies to desmocollin 3

We describe a case with clinical and histologic features of pemphigus herpetiformis associated with IgG and IgA anti-keratinocyte cell surface antibodies to desmoglein 1 (Dsg1) and exclusively IgG antibodies to desmocollin 3 (Dsc3). The clinical presentation was somewhat similar to IgA pemphigus; the main difference was the prevailing association with IgG antibodies to Dsg1. The presence of IgA anti-Dsg1 antibodies was confirmed by IgA enzyme-linked immunosorbent assay and IgG anti-Dsc3 antibodies were detected by a novel enzyme-linked immunosorbent assay with the use of baculovirus expressing recombinant Dscs for IgG and IgA. The reactivity of IgG antibodies with Dsc3 was confirmed by COS-7 cell cDNA transfection method using cDNA of human Dsc1 to Dsc3. We discuss the differentiation of pemphigus herpetiformis, associated with both IgG and IgA antibodies, from IgA pemphigus, particularly in regard to the autoimmune reaction with Dsgs and Dscs.