Intraoperative findings during temporal artery biopsy: keys to optimise the diagnosis of giant cell arteritis.

The objective of this study was to describe the perioperative findings during temporal artery biopsy (TAB) and the characteristics associated with a diagnosis of giant cell arteritis (GCA). Perioperative findings were prospectively described by a single operator blinded to the clinical and laboratory characteristics of the patients on 40 consecutive TABs, of which 21 were positive (53%) for GCA. Patients with a TAB positive for GCA (TAB+) more frequently had abnormalities on palpation of the temporal artery than negative TAB (TAB-) patients (mainly pulse abolition (p=0.007), indurated artery (p=0.002), and painful artery (p=0.021)). The appearance of a big artery (p<0.001), a thickened artery (p<0.001), and an indurated artery at incision (p<0.001) was significantly associated with a positive TAB. A multivariate model identified a big artery, no local bleeding, and pain during artery traction as being associated with TAB positivity (sensitivity 71.4% and specificity 89.5%). The appearance of the temporal artery during TAB is important in predicting the positivity of the biopsy. Whether this should influence the optimal length of the TAB warrants a prospective study.