A 58-Year-Old Woman With Urticaria, Fever, and Joint Pain

A 58-year-old woman with no allergies or rheumatic disease had a 2-year history of spontaneous wheals that occurred daily, accompanied by pruritus, arthralgia, and intermittent fevers; the wheals resolved after several hours without residual hyperpigmentation or bruising. C-reactive protein level was elevated, and skin biopsy showed dermal neutrophilic infiltration. What is the diagnosis and what would you do next?