A 6-year-old boy is brought to the accident and emergency department by his parents with a 5-day history of worsening eczema associated with malaise and lethargy. History In addition to worsening pruritus and sleeplessness, he complains of painful skin, particularly around his face, neck, chest and forearms. He quantifies the level of pain as 8 out of 10. His current flare is not responding to diligent application of his usual eczema treatments according to his ‘step-up’ management plan.

The onset of his eczema was at the age of 4 months, and although moderately severe in infancy it has been reasonably controlled since starting primary school, with regular use of emollients and mild to moderately potent topical steroids. His background history includes egg allergy (now partially outgrown in that he tolerates well-cooked egg in cakes) and asthma, currently stable. He has never been…