ABSTRACT
This chapter presents the case study of a 26-year-old woman attends the dermatology clinic complaining of a 4-month history of an itchy eruption. She describes the eruption as ‘cloud-like’. She previously suffered from eczema as a child but this rash is different. She tells you that although the eruption waxes and wanes, with individual lesions lasting 8 to 12 hours, she is rarely clear of lesions for more than half a day. Sometimes she goes to bed with the eruption and wakes clear, but the opposite can also occur. She has never experienced angioedema. The eruption is partially attenuated by cetirizine 10 mg daily, which she is taking for her hayfever. Her only other medication is occasional ibuprofen for dysmenorrhoea. The patient is suffering from urticaria, which is characterized by wheals or ‘hives’ that represent areas of cutaneous mast cell degranulation, releasing histamine and other mediators, followed by transient oedema and erythema.
