Erosive Pustular Dermatosis of the Scalp: A Clinicopathologic Study of Fifty Cases

Abstract

Erosive pustular dermatosis of the scalp (EPDS) is an uncommon, pustular, idiopathic disorder typically occurring on the scalp of the elderly, whose diagnosis requires close clinicopathologic correlations. Recently, the primary histopathologic characteristic of EPDS has been identified in some biopsies from hair-bearing scalp lesions as a sterile, vesiculo-pustule involving the infundibulum of hair follicles. To further delineate the clinicopathologic spectrum of the disease, we led a retrospective study of 50 patients (36 males and 14 females) with a diagnosis of EPDS between 2011 and 2021, reviewing clinical and histopathological data. Androgenetic alopecia was present in 32 patients. Triggering factors were present in 21 patients. The vertex was the most common location; one patient also had leg involvement. Two cases were familial. Disease presentation varied markedly from tiny, erosive, scaly lesions to crusted and hemorrhagic plaques, mimicking pustular pyoderma gangrenosum (PPG). Biopsies of patients with severe androgenetic or total baldness produced specimens showing nonspecific pathologic changes (39/50), while in 11 patients with a hair-bearing scalp histopathologic examination, changes were specific. The clinicopathologic similarities between EPDS and PPG suggest that EPDS should be included in the spectrum of autoinflammatory dermatoses. Clinicians could consider the possibility of associated disorders rather than managing EPDS as a sui generis skin disorder.

Erosive pustular dermatosis of the scalp and multiple sclerosis: just a coincidence?

“…4 Up to date, the pathogenesis of EPDS remains unknown, though a possible role of immunological senescence and autoimmunity has been suggested. [1][2][3][4][5][6] Interestingly, in a patient with EPDS and myasthenia gravis, Yu Sawada et al found high levels of neutrophil-stimulating cytokines and chemokines, (G-CSF, IL-6, and IL-8), which might be involved in the activation of an aberrant systemic neutrophilic reaction, shedding a light on the possible involvement of neutrophilic hyperactivation in the pathogenesis of EPDS, which seems to be in common with MG. 4 Furthermore, the role of neutrophils has been recently highlighted also in the pathogenesis of MS: spikes in plasma levels of CXCL5, have been associated with the development of new lesions in relapsing remitting MS. 5 The presented case is noteworthy suggesting a possible common immunological etiology of MS and EPDS, conceivably involving the hyperactivation of neutrophils, though this thesis would need to be confirmed by further studies.…”

Erosive pustular dermatosis of the scalp: a pathogenetic мystery and therapeutic challenge

“…The histopathological findings of the disease could be of a mixed type and is often confusing (2), but could include: 1) epidermal ulceration, epidermal atrophy, 2) sterile pustules with variable localization, 3) reduced to completely absent hair follicles, as well as 4) nonspecific mixed inflammatory infiltrate (3,4). According to other authors, the histopathological findings could be even more extensive or nonspecific, such as: 1) perifollicular granulomas, including remnants of hair follicles and giant multinucleated cells, 2) intrafollicular spongiform pustules, 3) neutrophilic microabscesses in the epidermis, 4) granulation tissue, 5) aggregates of macrophages and foreign body type giant cells, 6) diffuse dermal fibrosis, 7) dermal inflammatory infiltrate of lymphocytes and neutrophils (5). The problems in the treatment of this dermatosis arise, secondly, from the non-specific clinical picture, which makes clinicians quickly think in the direction of actinic keratoses and decide starting a radically different therapy.…”

“…Erosive pustular dermatosis of the scalp is a disease of unclear entity that predominantly affects the non-hairy area of the scalp in adults. 1 The pathogenetic mechanisms underlying this rare dermatosis remain unclear. 2 …”

“…According to other authors, the histopathological findings could be even more extensive or non-specific, such as: i) perifollicular granulomas, including remnants of hair follicles and giant multinucleated cells, ii) intrafollicular spongiform pustules, iii) neutrophilic microabscesses in the epidermis, iv) granulation tissue, v) aggregates of macrophages and foreign body type giant cells, vi) diffuse dermal fibrosis, vii) dermal inflammatory infiltrate of lymphocytes and neutrophils. 1 …”

Nonmelanoma skin cancer in the setting of erosive pustular dermatosis of the scalp: A case series and comment on management implications

“…Uplifting of the hyperkeratotic crusts reveals a copious purulent exudate underneath, a clinical finding suggestive of EPDS 1 . The condition is typically recalcitrant to treatment, with permanent cure being only exceptionally reported 3 . Although the pathogenesis of this condition is unknown, it is considered to be a neutrophilic inflammatory reaction associated with trauma, although chronic actinic damage and autoinflammatory conditions have also been implicated 1,4 .…”