Steroid use triggers severe psoriatic reaction

A 69-year-old man with well-controlled plaque psoriasis who presented to the emergency department for unilateral wrist pain was found to have calcium pyrophosphate deposition disease.Symptoms improved with a 7-day course of oral prednisone 30 mg twice daily without tapering.Attempts were made to control his symptoms with other recommended treatments for calcium pyrophosphate deposition disease, including colchicine and intra-articular steroid injection, but the pain recurred and only prednisone provided relief.Nonsteroidal anti-infl ammatory drugs were not started because the patient was on long-term anticoagulant therapy.Two rounds of prednisone 20 mg twice daily for 5 days with a 5-day taper to 7.5 mg daily were prescribed, with an intention to continue until a follow-up visit with a rheumatologist could be scheduled.After tapering the second round of prednisone, the patient developed a circular plaque bordered with