Scout is a 10-month-old girl brought in by her parents for review of an intermittently itchy and swollen skin lesion on her right deltoid region.

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<p>Scout is a 10-month-old girl brought in by her parents for review of an intermittently itchy and swollen skin lesion on her right deltoid region.</p><p>Her parents report the 1.5cm lesion has been present since around three months of age.</p><p>When it first developed, it looked flat and brownish, but in the past few months Scout has started to scratch it, after which it becomes raised and red for about 15 minutes.</p><p>She has no other similar lesions. Scout is otherwise well, with normal growth and development and reaching milestones as expected.</p><p>There is no family history of note. All immunisations are up to date and have been administered to the thighs.</p><p>On physical examination, a well demarcated, flesh-coloured macule is seen on the right arm (figure 1).</p><p>The lesion is rubbed firmly for five seconds, and within a few minutes becomes oedematous with a flare of surrounding erythema (figure 2). </p><p>Dermatological and systems examinations are otherwise unremarkable.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.