Erosive Pustular Dermatosis of the Scalp

Clinicopathological Correlation Leading to a Definition of Diagnostic Criteria

Robin Reschke, MD; Sonja Grunewald, MD; Uwe Paasch, MD; Marco Averbeck, MD; Jan C. Simon, MD; Tino Wetzig, MD

Disclosures

Wounds. 2021;33(6):143-146. 

In This Article

Results

The analyzed cohort consisted of 21 patients (18 men, 86%; 3 women, 14%) with EPDS. Typically, patients displayed thick crusts. After removing the crusts, pus and a shiny, glass-like layer of hypertrophic granulation tissue surfaced (Figure 1). Dermatopathological evaluation revealed a dermal infiltrate of lymphocytes and plasma cells in all 21 patients. These lymphoplasmacytic infiltrates were predominantly located in a perivascular pattern in the superficial and mid-dermis. In severe cases of EPDS, plasma cells formed dense infiltrates in the entire dermis (Figure 2) and appeared polyclonal. Neutrophils were detectable around the ulceration in 8 of 21 patients (38%). Name-giving pustules were not observed in any case, most likely owing to the removal of purulent crusts before the biopsy. In the punch biopsies residual hair follicles were rarely observed, and those that existed were located mainly in the marginal areas. The latter finding corresponds to the clinical observation of hair loss caused by EPDS.

Figure 1.

Clinical images of erosive pustular dermatosis of the scalp: (A) thick crusts; (B) crusts often adhered to hairs and were typically purulent underneath; (C) following the complete removal of crusts and pus, a shiny "granulation tissue" appeared; and (D) magnification of C to emphasize the shiny aspect of the tissue.

Figure 2.

Histopathology. Ulcerated epidermis with neutrophils within the ulceration; a dense, mixed infiltrate of lymphocytes and plasma cells spread over the entire dermis (hematoxylin-eosin, original magnification x40).

Triggers for EPDS in the patients in this study were cryotherapy, PDT, 5-fluorouracil, diclofenac gel, surgery, donor sites of split-thickness skin grafts, and trivial injuries of the scalp. In all cases, the skin had been damaged by actinic keratoses and skin atrophy. Fifteen of 21 patients (71%) developed EPDS in areas of the scalp affected by androgenetic alopecia. The condition existed between 3 and 24 months prior to the first consultation with a health care professional. Previous therapeutic attempts with disinfection and modern wound dressings were unsuccessful. Some patients had positive microbiological smears, showing colonization with Staphylococcus aureus or with Pseudomonas or Candida species. Although local antibiotic and antimycotic therapies achieved the eradication of bacteria and Candida species, the lesions did not heal. Seven patients also had diabetes mellitus. However, the vascular supply to the skin was intact in all patients. None of the patients were immunosuppressed. Erythrocyte sedimentation rate (ESR) was elevated in all 5 patients investigated. Elevated ESR seemed to correlate with disease severity as well as with the density of plasma cell infiltrates in the biopsies. These factors must be controlled in larger patient cohorts, however. In contrast, C-reactive protein was within normal range or only mildly elevated. Differential diagnoses that are associated with an elevated ESR, such as lymphoma, plasmocytoma, leukemia, other malignancies, severe anemia, hemolytic syndrome, nephrotic syndrome, de Quervain disease, polymyalgia rheumatica, giant cell arteritis, systemic lupus erythematosus, and severe systemic infections, were excluded in these patients.

All patients were treated with topical glucocorticoids (class III or IV), topical disinfection, and, if necessary, a topical antibiotic. This treatment resulted in complete healing within a few weeks (mean, 2.5 weeks) (Figure 3, Figure 4) as well as normalization of the ESR in all patients. One patient experienced recurrence; however, the patient responded well to additional treatment with topical steroids.

Figure 3.

Treatment response. (A) Shiny glass-like skin layer with peripheral crusts. (B) Completely healed skin with alopecia.

Figure 4.

Treatment response: (A) erosions and crusts; and (B) healed skin with alopecia.

Secondary alopecia was a typical effect of EPDS, notably owing to the inflammatory destruction of hair follicles (Figure 5). However, most patients in this study initially presented with androgenetic alopecia.

Figure 5.

Clinical-pathological correlation: (A) clinical images; (B) histological images; and (C) details of B.

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