IgA Vasculitis: a Review and Update on the Management of Renal and Extrarenal Disease, Highlighting What’s New for Biomarkers and Treatment

Abstract

Purpose of ReviewThis review summarizes recent advances in biomarker discovery and treatment of renal and extrarenal IgA vasculitis (IgAV), formerly known as Henoch-Schönlein purpura. Recent Findings Elevated levels of urinary IgA and serum galactose-deficient IgA1 at presentation are associated with risk of developing renal involvement. Elevated neutrophil to lymphocyte ratios at presentation may also indicate increased risk of renal but also gastrointestinal involvement. Rituximab has been beneficial in retrospective studies in the treatment of corticosteroid refractory IgAV nephritis. Although large studies have not conclusively demonstrated the superiority of any one steroid-sparing agent, MMF has emerged as a common steroid-sparing agent to help with disease control, while many other patients initially treated with steroids have also been switched to calcineurin inhibitors to control the glomerular disease. Summary Candidate biomarkers at presentation, specifically urinary IgA and neutrophil to lymphocyte ratios, may be helpful in risk stratifying patients at risk of developing IgAV nephritis. Further research is required in order to determine any recommendations for change in monitoring or management based on information gained from biomarkers. Guidelines recommend treatment of IgAV nephritis with corticosteroids, oral or intravenous depending on severity, renin-angiotensin-aldosterone system blockade, and the addition of cyclophosphamide for severe nephritis. For second-line therapies, in addition to azathioprine and mycophenolate mofetil, there is growing evidence to consider rituximab and calcineurin inhibitors.