KDIGO Releases Updated IgA Nephropathy, IgA Vasculitis Clinical Practice Guideline

Kidney Disease: Improving Global Outcomes (KDIGO) has released its 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV).1

Co-chaired by Jürgen Floege, MD, and Brad Rovin, MD, the guideline provides comprehensive, evidence-based recommendations for clinicians managing these kidney diseases, building upon the last update to the IgAN and IgAV management guideline published as part of the KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Based on new developments in IgAN assessment and therapy, a major update of the guideline was deemed necessary in 2024.1

"This guideline represents a fundamental shift in how we approach IgA nephropathy," Floege said in a statement.2 "For the first time, we can simultaneously target the immune mechanisms that drive IgA-containing immune complex injury and the maladaptive responses of the kidney to nephron loss. This dual strategy provides clinicians with a scientifically grounded roadmap to slow disease progression and extend kidney survival in ways that were not possible just a few years ago."

Regarding IgAN diagnosis, both versions of the guideline endorse similar approaches, although compared with the last version, the KDIGO 2025 IgAN guideline now encourages a more liberal kidney biopsy policy, suggesting it should be considered in all adults with proteinuria ≥0.5 g/d (or equivalent) in whom IgAN is suspected. Additionally, although the 2021 guideline recommended a treatment goal of proteinuria reduction to <1 g/d, guideline authors point to recent evidence suggesting a significant lifetime risk of kidney failure, therefore lowering this goal to <0.5 g/d while on or off treatment of IgAN, ideally <0.3 g/d (or equivalent), and a stable estimated glomerular filtration rate.1

A major new concept in the 2025 guideline is therefore a dual and concordant focus on treatments that aim to (i) prevent or reduce IgA-containing immune complex (IgA-IC) formation and IgA-IC–mediated glomerular injury and (ii) manage the consequences of existing IgAN-induced nephron loss.1

A major new concept in the 2025 guideline is to initiate treatment with therapies with a dual and concordant focus on the following:

• To prevent or reduce IgA-containing immune complex (IgA-IC) formation and IgA-IC–mediated glomerular injury
• To manage the consequences of existing IgAN-induced nephron loss

Approaches to achieve the first aim are currently limited to targeted-release budesonide (Nefecon). In settings where this is not available, the guideline suggests that patients who are at risk of progressive loss of kidney function with IgAN be treated with a reduced dose systemic glucocorticoid regimen combined with antimicrobial prophylaxis.1

As in the 2021 guideline, the 2025 guideline does not recommend treatment of IgAN with antiplatelet agents, anticoagulants, azathioprine, cyclophosphamide other than in the setting of rapidly progressive IgAN, calcineurin inhibitors, rituximab, or fish oil. While the guideline cites insufficient evidence to support the use of mycophenolate mofetil in non-Chinese patients, in Chinese patients, where trials have been conducted, it can be considered as a glucocorticoid-sparing agent.1

Approaches to managing the consequences of existing IgAN-induced nephron loss include healthy lifestyle education, reninangiotensin system blockers, sodium-glucose cotransporter-2 inhibitors, and/or dual endothelin angiotensin receptor blockers.1

The guideline authors noted little has changed for special situations of IgA-dominant immune complex glomerular diseases such as nephrotic syndrome, acute kidney injury, rapidly progressive glomerulonephritis, and pregnancy in IgAN, or children with IgAN or IgAV, citing the lack of major clinical trials in these patient populations.1

"The science is moving faster than ever, and the treatment landscape for kidney diseases driven by IgA has changed dramatically," Rovin said in a statement.2 "We now have multiple approved therapies such as targeted-release budesonide, sparsentan, and SGLT2 inhibitors that allow us to intervene earlier and tailor care to each patient's needs. What makes this guideline so important is that it shows clinicians how to integrate the latest evidence with practical strategies to preserve kidney function and improve lives. With this update, we are entering a new era where these conditions are no longer managed with a single approach but with a toolkit of therapies that can truly change outcomes for people with these complex diseases around the world."

References

1. Floege J, Barratt J, Cook HT, et al. Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV). Kidney International. doi:10.1016/j.kint.2025.04.004

2. KDIGO. KDIGO Announces Publication of IgAN/IgAV Guideline. September 18, 2025. Accessed September 18, 2025. https://myemail.constantcontact.com/KDIGO-Announces-Publication-of-IgAN-IgAV-Guideline.html?soid=1134196072483&aid=dvptZcsUezI