18F-Fluorodeoxyglucose positron emission tomography and serum cytokines and matrix metalloproteinases in the assessment of disease activity in Takayasu's arteritis

Abstract

© 2015 Elsevier Editora Ltda. Objective: To evaluate18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography-computed tomography (PET-CT)-and serum levels of different cytokines and matrix metalloproteinases (MMPs) in patients with Takayasu's arteritis (TA) and associations with disease activity. Methods: Serum levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-2, IL-6, IL-8, IL-12, IL-18, MMP-3 and MMP-9 were measured in 36 TA patients and 36 controls. Maximum standard uptake value (SUVmax) of 18F-FDG in arterial walls was determined by PET-CT scans. TA patients were classified as active disease, inactive disease and possible active disease. Results: Serum IL-6 and MMP-3 levels were higher in TA patients than in controls (p < 0.001). Serum IL-6 was higher in patients with active disease and in patients with possible active disease than in inactive disease (p < 0.0001). Patients with active disease had higher serum TNFα levels than patients with inactive disease (p = 0.049) while patients with possible active disease presented higher IL-18 levels than patients with inactive disease (p = 0.046). Patients with active disease had higher SUVmaxvalues than those with inactive disease (p = 0.042). By ROC curve SUVmaxwas predictive of active disease in TA and values ≥1.3 were associated with disease activity (p = 0.039). Serum TNF-α levels were higher in patients with SUVmax≥1.3 than < 1.3 (p = 0.045) and controls (p = 0.012). Serum IL-6 levels were higher in patients with SUVmax≥1.3 than in controls (p < 0.001). No differences regarding other biomarkers were found between TA patients and controls. Conclusions: Higher serum IL-6 and TNFα levels as well as higher arterial 18F-FDG uptake are associated with active TA.