A 23-year-old female presented with a 1-month history of a pruritic weeping lesion on her right leg, which started after scratching over this pruritic area. She did not mention any specific allergy. Examination revealed dry skin with round erythematous plaque with yellowish oozing and crusting over the right anterior tibial region. A clinical diagnosis of nummular (coin shaped) or discoid eczema was made. Treatment with a topical corticosteroid and an oral antibiotic was initiated which improved her symptoms. Maintenance of skin moisture was strongly advised.
Nummular eczema is an allergic disorder with pruritic coin-shaped patches on the skin (Fig. 1). It can sometimes be mistaken for ringworm or psoriasis. Men usually get nummular eczema late in their life while women get it at a younger age. Nummular eczema most commonly occurs on the extremities, particularly the legs, but may occur anywhere on the trunk, hands, or feet (1). The pathophysiology of this eczema is unclear; it is frequently associated with dryness of the skin, which may allow epidermal breach and permeation of allergens (2, 3). Severe, generalized nummular eczema has been reported in association with interferon and ribavirin therapy for hepatitis C (4) and tumor necrosis factor inhibitors (5).
Fig. 1.
Nummular eczema.
Conflict of interest and funding
The authors have not received any funding or benefits from industry or elsewhere to conduct this study.
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