Temporal artery biopsies: do they make the cut?

Abstract

Temporal artery biopsy is the gold standard investigation for giant cell arteritis. Guidelines recommend that specimens should measure no less than 1 cm and ideally more than 2 cm in length, as this influences the likelihood of biopsy positivity. This audit investigates the extent to which temporal artery biopsies acquired in our hospital meet these guidelines. Histopathology reports for all temporal artery biopsies performed at University Hospital Ayr between January 2011 and June 2013 were examined. Fifty-six temporal artery biopsy specimens showed a range in length from 0.5 cm to 3.1 cm, with a mean of 1.4 cm. Thirty-seven biopsies measured ≥1 cm (66%) and 13 were ≥2 cm (23%). Therefore, 19 samples (34%) did not meet the recommended standard. Just seven biopsies showed features of giant cell arteritis, with six of these measuring ≥1 cm in length (86%). The guidelines for temporal artery specimens are not being met at our centre. Furthermore, biopsies measuring ≥1 cm are much more common in the small group of positive results. This validates the minimum recommended biopsy length and displays the importance of achieving this standard. We suggest changes to increase the number of biopsies meeting these guidelines, improving the accuracy of this invasive test.