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.