Changes in complement activation in patients with ANCA vasculitis and paired samples from active and remission disease states. Changes in complement activation in patients with ANCA vasculitis and paired samples from active and remission disease states. Bb (A), properdin (B), C3a (C), C5a (D), sC5b-9 (E), C4d (F). Samples processed with futhan. Data were analyzed using the paired signed-rank test. A p-value <0.05 is considered statistically significant.