Acquired perforating dermatosis treated successfully with co
Perforating dermatoses are a group of uncommon conditions characterized by transepidermal elimination of dermal material (collagen, elastic tissue, or necrotic connective tissue), divided into primary and secondary forms

A 68-year-old male presented with a 6-month history of a pruritic eruption on the lower extremities. Examination showed multiple papulonodules with central umbilication and firmly adherent keratotic plugs on the extensor surfaces of the legs, predominantly on the right side. No mucosal lesions were noted. Besides pruritus, the review of systems was innocent for any other associated symptomatology.

The patient had been prescribed high potency topical corticosteroids 1 month before, with no significant improvement. His medical history was irrelevant and the patient denied similar complaints in close contacts. General condition was normal. Routine laboratory investigations, including extended biochemistry and autoimmunity, were within normal limits or negative.

Skin biopsy showed a well-demarcated crater-like ulcer filled with a thick plug containing fragments of keratin, numerous neutrophils, and transepidermal elimination of degenerated collagen fibers. The underlying dermis exhibited a mixed inflammatory infiltrate of lymphomononuclear cells, occasional neutrophils, and plasma cells. These findings were consistent with acquired perforating dermatosis.

At this point, colchicine 1 mg twice daily was added to the topical corticosteroid. The lesions rapidly improved, with a very significant reduction of the pruritus, subsiding a residual postinflammatory hyperpigmentation after 2 months of treatment.