Renal vasculitis causes damage to the small blood vessels inside the kidneys and - when untreated - can lead to a rapid loss of kidney function. Therapies that block the immune system to switch off the vasculitis process are available but can lead to serious infections and other long-term complications. The Cochrane Review of treatments to induce and maintain disease remission for renal vasculitis was updated in January 2020 and we asked lead author, Giles Walters from Canberra Hospital in Australia to bring us up-to-date with the findings.