Challenges of defining renal response in ANCA-associated vasculitis: call to action?

Abstract

Avoiding end-stage kidney disease in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) has a high therapeutic priority. Although renal response is a crucial measure to capture clinically relevant changes, clinal trials have used various definitions and no well-studied key surrogate markers to predict renal outcome in AAV exist. Differences in clinical features and histo-pathologic, and therapeutic approaches will influence the course of kidney function. Its assessment through traditional surrogates (i.e., serum creatinine, glomerular filtration rate, proteinuria, hematuria, or disease activity scores) has limitations. Refinement of these markers and the incorporation of novel approaches such as the assessment of histopathological changes using cutting-edge molecular and machine-learning mechanisms or new biomarkers could significantly improve prognostication. The timing is favorable, since large datasets of trials conducted in AAV are available and provide a valuable resource to establish renal surrogate markers and, likely, aim to investigate optimized and tailored treatment approaches according to a renal response score. In this review, we discuss important points missed in the assessment of kidney function course in patients with AAV and point towards the importance of defining renal response and clinically important short- and long-term predictors of renal outcome.

Evolution of Therapy for ANCA-Associated Vasculitis with Kidney Involvement

“…18 Stabilizing kidney function is a paramount therapeutic goal. 23,24 Glucocorticoids-A Double-Edged Sword for AAV Induction Therapy A 1958 retrospective description of 56 patients with WG (now GPA) documented an average survival of 5 months, with kidney and respiratory failure the leading causes of death. 25 A literature review in 1967 described improved survival in 26 patients with GPA who received glucocorticoids (GCs) compared with no treatment (12.5 versus 5 months).…”

ANCA-associated vasculitis—treatment standard

“…It is uncertain to what extent these urinary findings represent ongoing disease activity or persistent damage from the initial inflammation in the absence of repeat biopsy studies. New urine biomarkers such as soluble CD163 and MCP-1 have been investigated to gain insights into renal remission and treatment response [ 47 ]. An ongoing project by the ACR and EULAR is developing consensus composite response criteria for clinical trials [ 48 ].…”