Clinical features and outcomes of ANCA-associated renal vasculitis

To determine the patterns and outcomes of the pauci-immune vasculitis in the nephrology department at hospital La Conception in Marseille, we conducted a retrospective study including all patients with diagnosis of pauci-immune renal vasculitis between January 1, 2000 and December 31, 2007. Among 33 cases, 25 were diagnosed as Wegener granulomatosis (WG), seven as microscopic polyangitis (MPA) and one as Churg-Strauss syndrome (SCS). The median age of the patients was 57.7 years and the sex-ratio (M/F) was 1.6. The visceral manifestations included kidneys (100% of patients), lungs (75%), ENT (52% of WG), and nervous system (57% of MPA). The mean serum creatinine at admission was 3.3 mg/dL. Renal biopsies revealed a pauci-immune crescentic gromerulonephritis in 96% of the cases. Two patients with WG received plasmapheresis and seven patients required emergency hemodialysis. Induction therapy comprised cyclophosphamide IV and corticosteroids, while maintenance therapy included azathioprine for the majority of patients. Eighty four percent of the patients experienced complete remission after induction therapy. During maintenance therapy relapses were more frequent among patients with MPA (28%) compared to WG cases (12%). After 35 months of follow-up, eight patients ended on chronic hemodialysis, and five patients died. ANCA associated vasculitis are frequent in our patients. Long-term outcomes are relatively good despite a mortality rate of 15% and 25% of the patients entering dialysis after three years of follow-up.