Biopsy vs imaging for the diagnosis of giant cell arteritis. Viewpoint 2: in favour of biopsy.

Abstract

Objectives: Both temporal artery biopsy (TAB) and imaging are widely used to support the diagnosis of giant cell arteritis (GCA). The objective of this study was to compare the use of TAB and imaging.

Methods: This article was based on a debate presented at the 21st Vasculitis Meeting, discussing the advantages and disadvantages of using TAB with histology vs imaging for the diagnosis of suspected GCA.

Results: TAB is the diagnostic procedure with the highest specificity. Its sensitivity may be improved by removing an appropriate artery length, practice, examining multiple sections at various levels, and by recognizing incomplete histological findings (which may lead to a more definitive diagnosis by further sectioning or imaging or be related to other inflammatory diseases). TAB may provide histopathological clues useful for diagnosing GCA mimics that may produce similar imaging abnormalities. TAB is a useful research resource, and our current understanding of GCA physiopathology mostly relies on tissue immunopathology studies.

Conclusion: A suspected diagnosis of GCA should be supported by an objective test. TAB is the procedure with the highest specificity, and its sensitivity may be improved by training. Histopathologic examination provides data for an alternative diagnosis, when diseases other than GCA involve the temporal artery. Imaging is essential for the assessment of large-vessel involvement and allows follow-up studies.