The clinical and histopathological spectrum of IgA-pemphigus-report of two cases

Abstract

Two new cases of neutrophilic bullous disease exhibiting bound and circulating intercellular IgA in vivo in both direct and indirect immunofluorescence (IF), for which the term IgA-pemphigus was recently proposed, are presented. The first case showed a unique constellation of clinical and histopathological features not previously described for IgA-pemphigus, resembling both dermatitis herpetiformis and pemphigus, for which the designation IgA-herpetiform pemphigus seems most appropriate. The second case showed clinical and histopathological features mimicking subcorneal pustular dermatosis for which the previously used term IgA-pemphigus foliaceus seems most appropriate. The previously reported 11 cases showing similar direct IF findings, as well as our two patients, illustrate the main differences between IgA-pemphigus and classic forms of this condition: (a) different clinical manifestations with the absence of Nikolsky's sign; (b) scanty acantholysis; an abundance of neutrophils, with occasional neutrophilic spongiosis; (c) absence of C3 on direct IF; (d) the lower sensitivity of indirect IF and low levels of circulating antibodies; (e) the relatively benign course of the disease; (f) the apparent responsiveness to sulphones in many cases. It is suggested that IgA pemphigus should be considered as an entity separate from, but closely related to, classic pemphigus.

IgA pemphigus associated with monoclonal gammopathy completely resolved after achievement of complete remission of multiple myeloma with bortezomib, cyclophosphamide and dexamethasone regimen

“…IgA immunoglobulin deposits have been reported in a number of syndromes, some of them overlapping, including intraepidermal Ig pustulosis (or IgA pemphigus), intercellular IgA dermatosis and intercellular IgA vesicopustulous dermatosis [4]. Th e term intercellular IgA dermatosis has been proposed for the group of vesiculobullous dermatologic conditions with cutaneous IgA deposits detectable by immunofl uorescence [5].…”

Non-classical forms of pemphigus: pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus

“…48 There are many synonyms for IgA pemphigus: intraepidermal neutrophilic IgA dermatosis, intercellular IgA dermatosis, intercellular IgA vesiculopustular dermatosis, intraepidermal IgA pustulosis, IgA pemphigus foliaceus, and IgA herpetiform pemphigus. 47,49-57 …”

Pemphigus foliaceus masquerading as IgA pemphigus and responding to dapsone

“…The IEN variant is characterized by deep epidermal pustules and intercellular IgA deposits in the entire epidermis. [5] In the SPD variant, desmocollin 1 has been identified as the target autoantigen,[6] while in the IEN type, the autoantigen may be desmoglein 1 and 3 as reported by few studies. [7]…”