Discoid (nummular) eczema

 Discoid (nummular) eczema

Cause

No cause has been established but chronic stress is often present. A reaction to bacterial antigens has been suspected as the lesions often yield staphylococci on culture, and as steroid–antiseptic or steroid–antibiotic mixtures do better than either separately.

Presentation and course

This common pattern of endogenous eczema classi-cally affects the limbs of middle-aged males. The lesions are multiple, coin-shaped, vesicular or crusted, highly itchy plaques (Fig. 7.24), usually less than 5 cm across. The condition tends to persist for many months, and recurrences often appear at the site of previous plaques.

 

Investigations

None are usually needed.

Treatment

With topical steroid–antiseptic or steroid–antibiotic combinations .

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