Complications of therapy for ANCA-associated vasculitis

The introduction of immunosuppressive therapies has transformed ANCA-associated vasculitis (AAV) from a largely fatal condition to a chronic relapsing disorder. However, progressive organ damage and disability, both from the disease process itself and from therapies used for treatment, eventually affect the majority of patients. Infection, rather than uncontrolled vasculitis, is the greatest cause of early mortality and remains a major problem thereafter. Increased rates of malignancy and cardiovascular disease are additional important long term sequelae. This review focuses on the complications associated with the immunosuppressive therapies most commonly used to treat ANCA-associated vasculitis, and considers prophylactic and monitoring strategies to minimize these risks. Achieving a balance between immunosuppression to reduce relapse risk and minimizing the adverse effects associated with therapy has become key. The contribution of glucocorticoids to treatment toxicity is increasingly being recognized, and future therapeutic strategies must concentrate on glucocorticoid minimization or sparing strategies. Development of robust predictors of an individual's future clinical course is needed in order to individually tailor treatment regimens.