Unilateral or Bilateral Temporal Artery Biopsy for Suspected Giant Cell Arteritis?

Giant cell arteritis (GCA) is a patchy disease; pathologic findings in temporal artery biopsies are distributed unevenly. To determine the incidence of discordance between left and right temporal artery biopsies, Israeli researchers reviewed 173 consecutive cases in which biopsies were performed for suspected GCA.

Of 132 patients who underwent simultaneous bilateral biopsies, 51 had positive findings. Biopsy results were positive bilaterally in 38 cases and unilaterally in 13 cases. If only unilateral biopsies had been performed in the 13 discordant cases, half the diagnoses — 6 or 7 of the 51 positive cases, or 13% — could have been missed, assuming random choice of the right or left side.