Atypical Neutrophilic Dermatosis With Subcorneal IgA Deposits

Abstract

A 26-year-old woman had a chronic vesiculopustular and ulcerating skin disease associated with fever and arthritis. Cutaneous biopsy specimens showed an extensive infiltration of the dermis and epidermis by neutrophils. Direct immunofluorescence (IF) revealed linear subcorneal IgA deposits. Indirect IF showed IgA antibodies reactive with the subcorneal zone of normal epidermis. The disease responded to dapsone therapy. The association between neutrophilic dermatoses, including pyoderma gangrenosum, subcorneal pustular dermatosis, and related entities, and IgA involvement, either IgA gammopathies and/or intraepidermal IgA deposits, is emphasized. Intraepidermal IgA deposits are possibly involved in the pathogenesis of our patient's condition and of other cases of unusual neutrophilic dermatoses.

Intra-Epidermal Immunoglobulin A Pustulosis

“…In the majority of the reported cases, IgA is located on the so-called intercellular substance of the epi dermis. This obviously resembles the pemphigus immu- [5][6][7] may constitute a distinct entity. This is however not a defi nite conclusion.…”

“…It is interesting to note that there is already some heterogeneity among these observations, and this results in some controversy about the denomina tion of the disease and its nosology. Zillikens et al pro pose to classify these patients into three subgroups; IgA pemphigus, as proposed by Beutneret al [3], is itself sub divided into a subcorneal type and an intra-epidermal type; the third subgroup includes 3 cases with subcorneal IgA deposits [5][6][7].…”

“…A careful reading of the published clinical descriptions of IEAP shows that, in contrast to pemphi gus foliaceus, it is in nature a pustular disease, sometimes identical to typical Sneddon-Wilkinson disease, some times different. The pustules in IEAP may also form a part of a more complex neutrophilic dermatosis [6].…”

Subcorneal Pustular Dermatosis and IgA Myeloma

“…T he associ ation between IgA gammopathy and SCPD, a neutrophilic dermatosis, is probably not coincidental [2]. Wallach et al [13] suggest a pathological link between IgA dysfunction and neutrophilic disorders.…”

“…There have been reports of SCPD with intraepidermal deposits of IgA, and few of these have been associated with IgA paraprotcinaemias [10], There have also been reports of intra-cpidermal pus tules and acantholysis as opposed to subcorneal pustules associated with intra-epidermal IgA deposits [10,13], At present there is a controversy as to whether they constitute a different clinical entity. The term intra-epidermal immu noglobulin A pustulosis has been recently suggested [ 15].…”