Giant cell arteritis (GCA) is a systemic immune-mediated vasculitis characterized by granulomatous inflammation. Temporal artery biopsy (TAB) is performed in patients suspected of GCA. We investigated the ten-year results of TAB owing to a suspicion of GCA in a tertiary hospital in Iran.

In this retrospective study we reviewed the chart of all cases who underwent TAB during the last 10 years from 2006 to 2016. Patients were diagnosed with GCA based on clinical features that fulfilled the American College of Rheumatology (ACR) 1990 criteria. Baseline clinical and laboratory data, histopathological reports and TAB length were obtained from medical records.

From 110 patients with GCA, only 13 patients had positive TAB (11.8%). Forty one of patients (37.3%) were men. The mean age of patients was 65.08±9.97. Although the length of TAB (1.93±0.73 versus 1.56±0.84) was higher in positive ones in comparison with negative ones, it was not statistically significant (P=0.13). Also ESR (55.91±35.15 vs 51.60±28.69), CRP (8.01±18.97 vs 25.20±38.55), Hb (12.41±2.91 vs 11.95±1.82) and Platelet count (288.30±124.82 vs 267.05±97.52) were not statistically significantly different between positive and negative TAB groups. Mean age was significantly higher in positive TAB group (75.00±8.04 vs 63.57±9.35, P<0.001).

The lower rate of positive TAB among GCA diagnosed patients in comparison with other studies was found. As the length of TAB did not statistically significant different between positive and negative ones, the lower rate of positive sample did not associate with the length of the TAB.