Case 2: Diagnostic Testing

Case 2 Index

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Initial results


Choose the three most high yield diagnostic test to perform next!
ANCA panel
Incorrect. This patient’s distribution of symptoms suggests a large-vessel vasculitis. ANCA-associated vasculidities classically affect small vessels. Check out our vasculitis schema to learn more!
Carotid Doppler Ultrasound
Correct! The patient’s symptoms of transient visual changes in the days prior to her complete vision loss suggests she was experiencing amaurosis fugax, which is considered a TIA. Both Carotid US Doppler and transthoracic ECHO are part of the routine workup for TIA and should be obtained in this patient. She does have a history of hypertension and hemorrhagic stroke. Evaluation for atherosclerotic plaque, as well as for thromboembolic phenomenon due to occult atrial fibrillation, are reasonable low-cost steps in this patient’s workup.
Correct! Elevated inflammatory markers would further support the diagnosis of an active vasculitis in this patient.
Temporal Artery Biopsy
Precisely! The patient’s age, symptoms, and retinal exam findings are concerning for cranial GCA. Temporal artery biopsy is the gold standard for diagnosis. While temporal artery ultrasound could be considered, our pre-test probability of the disease is high enough, such that if the US was negative, it would not rule out GCA. The biopsy would still need to be pursued to help establish definitive diagnosis of GCA and help exclude mimics, such as endocarditis.
Incorrect. This patient’s clinical history and age make SLE very unlikely. The prevalence of positive ANA increases with age (~35% positive in adults over 50), so we almost expect it to be positive and not diagnostically helpful. 


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Case 2 Index
Case 2 Introduction
Case 2 Review of Systems

Case 2 Physical Exam