Bilateral sequential vision loss from giant cell arteritis with persistently low inflammatory markers
Authors: Hillary Chan1, Jonathan Micieli2. 1University of Toronto, 2Kensington Vision and Research Centre.
Author Disclosures: Hillary Chan: None Jonathan Micieli: None
Abstract Body:
Purpose: To describe a rare case of sequential vision loss with persistently normal erythrocyte sedimentation rate (ESR) and C‐Reactive protein (CRP) separated by 3 months in biopsyproven giant cell arteritis.
Study Design: Case report.
Methods: Chart review.
Results: An 86‐year‐old woman was referred for left eye vision loss. She had a past medical history of dementia, type 2 diabetes, hypothyroidism, previous stroke and hypertension. She woke up with left eye vision loss two weeks prior to presentation. She denied headache, jaw claudication, scalp tenderness, neck pain, fever, loss of appetite, fatigue or muscle stiffness or pain. Examination reviewed a visual acuity of 20/25 OD and 20/40 OS with a left relative afferent pupillary defect and left optic disc edema. There was a right disc at risk. She was diagnosed with a left anterior ischemic optic neuropathy without any concerning features for GCA based on history. Investigations revealed an ESR of
47mm/hr, C‐reactive protein of 4.9mg/L (normal less than 5.0mg/L) and platelet count of 379 (normal 150‐400x E9/L). She was diagnosed with left non‐arteritic anterior ischemic optic neuropathy (NAION) and a 3 month follow‐ was arranged. She returned for the 3‐month follow‐up and her caregiver reported that she had been complaining of headache for the past month and it seemed as if her vision was worse. Her visual acuity was light perception in the right eye and counting fingers OS. She had bilateral tonic pupils and dilated fundus examination showed right diffuse retinal edema, a cherry red spot and significant attenuation of the retinal arterioles OD and left optic disc pallor. Repeat blood work was obtained that day and showed a platelet count of 523 xE9/L, ESR of 25mm/hr and CRP of 1.7mg/L. A temporal artery biopsy was performed and confirmed the diagnosis of giant cell arteritis since there was an inflammatory infiltrate centered on the internal elastic lamina. She was treated with Prednisone 1mg/kg and her caregiver reported that she no longer complained of headaches.
Conclusions: Giant cell arteritis may rarely present with normal inflammatory markers and these may remain normal even months after initial presentation. Platelets may be the only hematological parameter that increases over time. A temporal artery biopsy remains an important diagnostic test to confirm the diagnosis when there are low inflammatory markers but still a reasonable suspicion of GCA.
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