Recurrent ANCA-associated small vessel vasculitis after transplantation: A pooled analysis

Background. Recurrent antineutrophil cytoplasmic antibody (ANCA)- associated small vessel vasculitis (ANCA-SVV) after renal transplantation has been described in case series. However, general information regarding the frequency, character, and predictors of recurrent disease after transplantation is currently lacking. We considered the rate of relapse, whether a positive ANCA at the time of transplantation predicted relapse, and whether cyclosporine A prevented recurrent disease. Methods. We performed a pooled analysis of published data, added to the experience at the Universities of North Carolina (14 patients) and Lund, Sweden (11 patients). To avoid reporting bias, only case series were included for analysis. Subgroup analysis was performed by disease category (Wegener's granulomatosis, microscopic polyangiitis, or necrotizing crescentic glomerulonephritis) and ANCA staining pattern. Results. ANCA-SVV recurred in 17.3% of all patients (N = 127), in 20% of cyclosporine A-treated patients (N = 85), and in 25.6% of patients with circulating ANCA at the time of transplantation (N = 39). There was no statistically significant difference in the relapse rate between patients treated and those not treated with cyclosporine A (P = 0.45), between those with and without circulating ANCA at the time of transplant (P = 0.75), or between patients with Wegener's granulomatosis and those with microscopic polyangiitis or necrotizing crescentic glomerulonephritis alone (P = 0.62). Conclusion. There is a substantial relapse rate in the ANCA-SVV population. Therapy with cyclosporine A does not protect against recurrent ANCA-SVV, and the presence of a positive ANCA at the time of transplantation does not preclude transplantation. These conclusions must be substantiated with a prospective study of renal transplantation in patients with ANCA-SVV so as to optimize their management.