Clinical and pathological characteristics and outcomes of Chinese patients with primary anti‐neutrophil cytoplasmic antibodies‐associated systemic vasculitis with immune complex deposition in kidney

Abstract

To analyse the clinical and pathological characteristics of Chinese patients with immune complex deposition in kidney in anti-neutrophil cytoplasmic antibodies (ANCA)-positive vasculitis. Enrolled in this study are patients with immune complex deposition in kidney in ANCA-positive vasculitis diagnosed in Peking University First Hospital. Their clinical and pathological data were collected and analysed. Twenty-three patients were eligible. Fifteen patients were with microscopic polyangiitis and eight patients were with Wegener's granulomatosis. The mean age was 48.8 years and with a male/female ratio of 10/13. The interval, between onset of disease and the diagnosis of disease, was 429.6 +/- 693.3 days. All patients had clinical evidence of renal involvement. The major immunoglobulin deposited was IgM and the main locations were mesangial and sub-epithelial area. Four patients also presented features of membranous nephropathy and six patients presented features of IgA nephropathy. About 52.2% of patients had hypocomplementaemia. All patients received immunosuppressive therapy and all of them achieved clinical remission. Patients were followed for about 28.8 +/- 25.3 months. Nine patients kept clinical remission, nine patients progressed to end-stage renal disease and five patients died. When these patients are compared with patients who had classical pauci-immune vasculitis, they had greater proteinuria (P < 0.05), higher prevalence of hypocomplementaemia (P < 0.05) and greater glomerular cellularity (P < 0.05). The present study showed that the features of patients with ANCA-associated vasculitis with immune complex deposition in kidney were similar with classical 'pauci-immune' vasculitis except for more proteinuria, more hypocomplementaemia and greater glomerular hypercellularity.