A 44-year-old white woman presented with an 8-week history of increasing bilateral (right more than left) ankle pain with progressive periarticular edema and inflammation. The right wrist and both elbows were additively and mildly involved. She had intermittent fever with no clear pattern, malaise, mild thoracic spine pain, and intermittent limb muscle aches. Dry cough was present 4 days before hospital admission. The patient was treated with nonsteroidal antiinflammatory drugs and morphine at another hospital for 4 days before being transferred to our institution for management of asymmetric large-joint polyarthritis of unclear etiology. She denied sputum production, dyspnea, chest pain, syncope, headaches, visual disturbances, nausea, vomiting, abdominal pain, diarrhea, history of bleeding, dysuria, night sweats, weight loss, and skin rash. She was a resident of a small rural town, had a stable monogamous relationship with her husband, and had one healthy son. She worked for a local home health-care agency and denied tobacco, ethanol, drug abuse, recent exposure to animals, and recent travel. No drug allergies were noted. Home medications included glyburide/metformin (2.5/500 mg po bid), lisinopril (10 mg/d po), and ibuprofen as needed.