The Clinical Characteristics, Treatment, and Outcomes of Giant Cell Arteritis are Dependent on Histological Subtype

Objective: To determine the clinical outcomes of the two histopathological patterns considered positive for giant cell arteritis (GCA): active arteritis and healed arteritis. Methods: A retrospective chart review was performed of 22 patients with biopsy-proven GCA. Eleven patients had active arteritis and eleven patients had post-inflammatory alterations consistent with healed arteritis. We sought to compare presenting symptoms, ischemic ocular events, inflammatory markers (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and platelet count), relapses, and dosage requirements of long-term steroids between the two groups. Results: 7 of 11 patients with active arteritis had an initial ocular ischemic event while 3 of the 11 patients with healed arteritis had an initial ischemic event to the eye. There was no statistical difference in initial ESR between the two groups, but CRP and platelet counts on initial presentation were statistically higher in the active group (p = 0.0002 and p <0.0001 respectively). Patients with active arteritis on biopsy required higher doses of steroids over a 2-year follow-up compared to the healed group: on average 11 mg/day to 1 mg/day at 1 year (p = 0.0008), and 7 mg/day to 0.5 mg/day at 2 years (p = 0.0208), respectively. During the follow-up period, 2 of the 11 patients in the active group demonstrated a recurrent ischemic event to the eye same or fellow eye while in the healed group there were no recurrent ischemic events. Conclusions: Patients with healed arteritis on pathological examination of temporal artery biopsy appear to have better prognoses and may require less aggressive treatment than those with active inflammation.