Giant cell arteritis in a neuro-ophthalmology clinic in Saskatoon, 1998-2003

Background: We present a retrospective review of all biopsy-positive cases of giant cell arteritis (GCA) presenting to a neuro-ophthalmology practice in Saskatoon, Saskatchewan.Methods: Records of 141 consecutive patients who underwent temporal artery biopsy at the Saskatoon Eye Centre from July 1998 through June 2003 were reviewed. Patients that were biopsy-positive for GCA were studied and an estimated regional incidence was calculated. Study variables included age at diagnosis, sex, ethnicity, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) level.Results: Of 141 patients, 37 (26%) had a positive biopsy result for GCA; 11 underwent a second biopsy for a total of 152 biopsies. The average age of the biopsy-positive patients was 76.5 (SD 8.2) years, and the female-to-male ratio was 2.4:1. There were 35 patients (95%) of European descent and 2 patients (5%) of Aboriginal descent. Twenty-three patients had both ESR and CRP testing done before starting steroids. The ESR was elevated in 19 (83%) and the CRP in 22 (96%). The estimated incidence of GCA for Saskatoon and area was 9.4 per 100 000 for people over the age of 50 years.Interpretation: GCA occurs primarily in people of European descent; however, it can affect North American people of Aboriginal descent. Sensitivity for the detection of GCA is higher in CRP than in ESR. The estimated incidence of GCA in Saskatoon and surrounding referral area is moderate compared with other northern areas.