When should a temporal artery biopsy be performed on a patient with Polymyalgia Rheumatica?
A temporal artery biopsy in PMR is not necessary unless the patient’s symptoms or signs suggest the presence of GCA.
Therefore, the history in a patient suspected of having PMR should always include questions regarding fever, current or recent headache, jaw or tongue claudication, visual disturbance, and scalp tenderness. The arteries of the head, neck, torso, and extremities should be examined for tenderness, enlargement, bruits, decreased pulsation, and the blood pressure in both arms should be measured for discrepancy. Constitutional symptoms and laboratory values in PMR and GCA are similar and, therefore, do not distinguish between the two. However, the failure of prednisone (20 mg/day) to significantly improve symptoms or to normalize the ESR/CRP within 1 month should suggest the presence of GCA and prompt temporal artery biopsy and/or search for another diagnosis (e.g., malignancy or infection).
