Serum levels of soluble interleukin-2 receptor in patients with ANCA-associated vasculitis

Serum soluble interleukin-2 receptor (sIL-2R) concentrations were determine d using the ELISA method in 19 cases of ANCA-associated vasculitis. These p atients were classified as 7 cases of Wegener's granulomatosis (WG) and 12 cases of microscopic polyangiitis (MPA). Elevated levels of sIL-2R were pre sent in the sera of these patients. Levels of serum sIL-2R were not signifi cantly different in patients with WG and MPA either in the active or inacti ve phase, so the results were expressed as a unified ANCA associated vascul itis group. Concentrations of serum sIL2R were significantly higher in ANCA -associated vasculitis during the active phase than during the inactive pha se (p<0.05), and serum sIL-2R levels were significantly increased in these patients, in the active or inactive stage, compared with a group of healthy subjects (p<0.05). In patients with vasculitis, serum sIL2R levels correla ted with serum levels of C-reactive protein (p<0.05). In the active phase, concentrations of serum sIL2R correlated to creatinine concentrations. No c orrelation was found between sIL-2R and ANCA levels in any of the stages of the disease. These findings suggest cellular immune activation in ANCA ass ociated vasculitis.