Lack of sensitivity of indium-111 mixed leukocyte scans for active disease in Takayasu's arteritis.

Abstract

Currently, a reliable, noninvasive means of detecting the active vasculitic lesions of Takayasu's arteritis does not exist. Based on the cellular infiltrates seen in active lesions, we postulated that indium-111 labelled mixed leukocytes could be used to scintigraphically detect sites of active vasculitis. Fifteen In-111 mixed leukocyte scans were performed in 10 patients with Takayasu's arteritis and correlated with clinical, laboratory, and radiographic findings. Patients had either active, stable/smoldering, or inactive disease at the time when 8, 4, and 3 scans were performed, respectively. Two of the 8 scans performed in patients with active disease were positive for increased vessel uptake (sensitivity = 25%). All other scans were interpreted as negative for active arteritis. We conclude that In-111 mixed leukocyte scans have a low sensitivity for detection of active Takayasu's arteritis.