ANCA-positive IgA nephropathy without necrotising or crescentic glomerulonephritis: a clinical conundrum.

IgA nephropathy, the most prevalent form of primary glomerular disease, usually portends a favourable outcome. Antineutrophil cytoplasmic autoantibodies (ANCAs) have been reported in association with IgA nephropathy in a small subset of patients, mostly presenting with rapidly progressive glomerulonephritis and necrotising crescentic lesions. Herein, we describe a case of IgA nephropathy, positive serum cytoplasmic and perinuclear ANCAs with anti-myeloperoxidase antibody, and preserved renal function without any histological evidence of necrotising or crescentic glomerulonephritis. Based on available mechanistic and clinical data, we opine that such patients could benefit from close monitoring of renal function. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.