Giant Cell Arteritis With Normal Inflammatory Markers and Progressive Visual Disturbance.

Giant cell arteritis (GCA) is a large vessel vasculitis classically presenting with headache, jaw claudication, visual disturbance, and raised inflammatory markers. However, atypical presentations occur, and a delay in recognition can lead to irreversible visual loss. We report a 75-year-old male with sequential ocular involvement in whom erythrocyte sedimentation rate and C-reactive protein remained within normal limits. Carotid/vertebrobasilar imaging showed atherosclerotic change without critical stenosis, and 18F-fluorodeoxyglucose PET demonstrated vertebral arterial uptake consistent with cranial GCA. High-dose corticosteroids were commenced with rheumatology input. Normal inflammatory indices do not exclude GCA. Clinicians should maintain a high index of suspicion when visual symptoms evolve and initiate treatment without delay where clinical probability is high.