Another common population is atopics in the second and third decades. Nummular dermatitis is rare in children. Lesions begin as papules or vesicles that coalesce to form confluent plaques with an erythematous base. Early lesions may be exudative and crusted, and due to the moist environment, often become colonized by staphylococci, which increases the severity and duration of the lesion. Secondary frank infection may occur, necessitating systemic antibiotics.
Late lesions are dry, scaly, and are often excoriated secondary to moderate pruritus.
Patients may report a burning sensation. The lower extremities and dorsum of the hand are the most frequently affected areas, though arms, trunk and thighs may also be affected. Irritant hand dermatitis may present as a nummular pattern. Local trauma, irritating conditions and venous stasis may play a role in the pathogenesis. Xerosis may also play a role.