Introduction: Temporal artery biopsy is the gold standard for the diagnosis of giant cell arteritis (GCA). There is disagreement over how long the temporal artery specimen should be, i.e. 0.5 cm or over 2.5 cm to increase diagnostic sensitivity.

Objective: To investigate the relationship between temporal artery biopsy length and diagnostic sensitivity for giant cell arteritis (GCA).

Methods: A retrospective observational study among a consecutive cohort of all individuals who underwent temporal artery biopsy at Cruces Universitary Hospital between 1st January 2000 and 31st December 2007, was performed. A biopsy was considered positive for GCA if there was a rupture of internal elastic lamina with cell infiltrate predominating at the media–intima junction or in the media with or without giant cells. All biopsies were reviewed by a single, independent, blinded pathologist.

Results: 342 patients were included, 156 men and 186 women. The mean age of patients with GCA+ was 74.9 (DS6.7). All patients were over 50 years and the youngest affected of GCA+ was 57 years. The mean specimen size of biopsy was 1.26 cm (0.87–1.65). The mean length was 1.20 cm (0.82–1.58) in women and 1.35 cm (0.96–1.74) in men. 71 patients had a histological GCA (20.76%). The length was 1.28 cm (0.92–1.64) in GCA+ and 1.23 cm (0.89–1.57) in GCA−. There was no significant difference (ANOVA).

Conclusion: An artery specimen of 1 cm is sufficient for the histological diagnosis of GCA.

Conflict of interest: None declared.