Wu EY, et al. - Ninety-eight patients with ANCA vasculitis were included by the researchers in a case-control study in order to examine complement activation in MPO-ANCA and PR3-ANCA vasculitis post-ascertainment of the optimal methods for measurement of the activated complement factors in circulation. Higher levels of C5a and sC5b-9 were noted in active MPO-ANCA vasculitis and in remission. C3a and C4d were also noticed higher in remission. On comparing paired active and remission disease samples within patients, significant difference sC5b-9 were noted. Also, amongst patients in long-term remission off therapy C5a was significantly inferior. In comparison to futhan, patient samples processed without futhan had considerably higher median levels and individual values of Bb, C5a, and sC5b-9. Hence, the occurrence of complement activation both MPO-ANCA and PR3-ANCA vasculitis was observed. Further, the difference in the complement activation profile via disease activity and possibly ANCA serotype was noted. Furthermore, futhan decreased in vitro complement activation and presented a more accurate measurement. .