Is it giant cell arteritis? : a retrospective audit on temporal artery biopsy for giant cell arteritis

Abstract

Background: Giant cell arteritis (GCA) is the commonest of the vasculitides and should form part of the differential diagnosis of a new-onset headache in patients over 50 years with elevated inflammatory markers. Temporal artery biopsy (TAB) is the gold standard for its diagnoses. Aim: The aim of this audit was to determine whether patients referred for a TAB between 2010 and 2015 at Mater Dei Hospital qualified for a diagnosis of GCA and the significance of the TAB result in affecting management of GCA by correlating the clinical profile and biochemical criteria according to the guidelines based on the American College of Rheumatology (ACR) criteria. Results: The percentage of positive TABs in our cohort of 170 patients was 23%. The ESR (sensitivity - 100%) was shown to be a significant factor associated with a positive TAB when compared to CRP (sensitivity 90%). 79.5% of positive TAB results were patients aged between 70-89 years of age, proving age is also a significant factor. New onset headache was the most common complaint (66%). Only 45.9% of patients were started on steroids prior to TAB despite the clinical suspicion of GCA. This increased to 54.1% of patients on steroids after TAB was performed, pending a histology result. Conclusion:Our findings, which are similar to comparing studies, question the practicality of TAB in the clinical diagnosis of GCA. Clinical symptoms, raised ESR and increasing age proved to be significant factors contributing to the clinical diagnosis and management of GCA. Non-invasive ultrasonography can further confirm the diagnosis and is to replace TAB in the near future.