A 59-year-old woman had a 1-month history of polyarthralgia and swelling in the joints of her hands and feet. She then developed lower back pain and confusion. On examination, she was pyrexic and tachycardic. Edema and tenderness of the wrists and interphalangeal joints were noted.
Investigations showed an increased C-reactive protein level of 265 mg/L (to convert to nanomoles per liter, multiply by 9.524). Blood culture results were positive for Staphylococcus aureus. A chest x-ray, urine culture results, transthoracic echocardiogram, and abdominal ultrasonography scan were normal. Treatment with broad-spectrum intravenous antibiotics was commenced.