Objective: We investigated the diagnostic value of inflammation limited to the adventitia (ILA), and isolated vasa vasorum or small-vessel vasculitis (VVV, SVV) in temporal artery biopsies (TAB) for giant cell arteritis (GCA).
Methods: Two pathologists reviewed consecutive first TAB. Using the clinical diagnoses as the gold standard, positive predictive values (PPV) were calculated.
Results: Among the 75 patients without classic TAB features of GCA, 8 had GCA diagnoses. The PPV of ILA, VVV, and SVV seen by either or both pathologists were 17%, 0%, and 7%, and 17%, 0%, and 10%, respectively.
Conclusion: (Peri)adventitial infiltrates in TAB poorly predict GCA.
Keywords: GIANT CELL ARTERITIS; SMALL-VESSEL VASCULITIS; TEMPORAL ARTERY BIOPSY.