AMCmiddle twist
A 72-year-old woman has developed a new unilateral temporal headache over three weeks. She reports pain when chewing and two recent episodes in which vision in the right eye became grey for several minutes. Her temporal artery is tender, the erythrocyte sedimentation rate is 88 mm/hour (reference range 1–30), and the C-reactive protein is 112 mg/L (reference range less than 5). Which one of the following should be undertaken immediately?