(BMJ)—A 74-yo woman w/ hx of bowel CA and HTN presented w/ a constant HA lasting several wks, jaw pain, and intermittent blurring of vision in her L eye that culminated in complete vision loss 3 days before presentation. She felt generally unwell, w/ increasing lethargy and myalgia. Exam: Tender, pulseless temporal arteries. CRP = 256 mg/L. Despite the fact that appropriate tx was instituted promptly, the opposite eye deteriorated 3 days later. Fundoscopy, OD: swollen, pale, “chalky white” optic nerve. What was the dx?
Endocarditis
Acute angle-closure glaucoma
Giant cell arteritis
Retinal vein occlusion
Wegener granulomatosis
You are correct. The pt’s sx, fundoscopy findings, and raised CRP suggested giant cell arteritis (GCA). Temporal artery bx confirmed the dx. Arteritic anterior ischemic optic neuropathy, as seen in this case, occurs in 20% to 50% of pts w/ untreated GCA. The 2nd eye is also affected in 30% of pts, often w/in the 1st wk. The pt was treated w/ 1 g/day IV methylprednisolone x4 days, then 60 mg/day oral prednisolone thereafter. Although her sx and blood test results improved, the changes in her vision were irreversible, and her vision remained poor.

BMJ 2016;353:i3055