A 26-year-old man presented with a 15-year history of a nodule on the back of his neck (Figure 1, arrow). The lesion, which was occasionally swollen, was itchy when it was rubbed by a shirt collar and painful when it became edematous. The patient had been diagnosed as having allergic rhinitis and bronchial asthma since childhood. Episodic fever had occurred every 1 to 2 months in the past year. The fevers lasted for 1 to 9 days, with temperatures of 38°C to 39°C, until oral medication was prescribed. There was no flushing, headache, tachycardia, diarrhea, bone pain, or peptic ulcer. However, the patient had had constipation every 2 to 3 days for 14 years and constant malaise over the past 6 years.
Chang I, Yang C, Sung F, Ng K. A Red-Brown Plaque on the Nape—Quiz Case. Arch Dermatol. 2004;140(10):1275-1280. doi:10.1001/archderm.140.10.1275-e