Clinicopathological Characteristics of Adult IgA Nephropathy in the United States
Kidney International Reports – 2023
KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)
Journal article
Published on September 18, 2025
Contributors:
KDIGO Glomerular Diseases Work Group
KDIGO Glomerular Diseases Work Group
DOI:
10.2215/CJN.0000000000000135
10.2215/CJN.0000000000000135
Summary
Overview
The Kidney Disease: Improving Global Outcomes (KDIGO) 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV) is an update to Chapter 2 of the 2021 KDIGO Guideline for the Management of Glomerular Diseases.1
The update incorporates evidence from randomized controlled trials through August 2024 and provides recommendations on diagnosis, prognosis, treatment, and special situations.1
Guidance is based on systematic evidence reviews and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.1,2
Explore our KDIGO IgAN 2025 infographic
Diagnosis
IgA nephropathy can only be diagnosed with a kidney biopsy, as no validated serum or urine biomarkers exist.1
Biopsy is recommended in adults with proteinuria ≥0.5 g/day (or equivalent) when IgA nephropathy is suspected and no contraindications for biopsy are present.1
Prognosis
Risk stratification in IgA nephropathy is based on clinical and histologic findings, supported by validated prediction tools1:
- The International IgAN Prediction Tools estimate the risk of a 50% decline in estimated glomerular filtration rate (eGFR) or kidney failure up to seven years after biopsy.1 Versions are available for adults and children, both at the time of biopsy and one to two years later1
- These tools incorporate clinical information and biopsy features to guide prognosis and support shared decision-making1
- No prognostic biomarkers are validated beyond proteinuria and eGFR1
Treatment goals and targets
Patients with IgA nephropathy who have proteinuria ≥0.5 g/day (or equivalent) are at risk of progressive kidney function loss and should start or escalate therapy.1
The goal of treatment is to slow kidney function decline to <1 mL/min per year.1
Clinical decision-making can be guided by urine protein excretion, which should be maintained at <0.5 g/d at a minimum, but ideally at <0.3 g/d.1
Strategies to achieve treatment targets
For patients who are at risk of progressive kidney function loss, management of IgA nephropathy focuses on both addressing the consequences of nephron loss and preventing or reducing immune complex-mediated injury.1
Managing the responses to IgAN-induced nephron loss
Interventions for all patients with IgA nephropathy1:
- Lifestyle measures, where appropriate, including dietary sodium restriction (<2 g/d), smoking and vaping cessation, weight control, and regular exercise1
- Blood pressure control to a target of ≤120/70 mm Hg1
- Cardiovascular risk assessment with initiation of appropriate preventive interventions1
Reduction of glomerular hyperfiltration and the impact of proteinuria with1:
- An optimized maximally tolerated dose of an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin II receptor blocker (ARB) (GRADE: 1B)1
- Sparsentan (not to be used in combination with a renin-angiotensin system inhibitor [RASi]) (GRADE: 2B)1
- A sodium-glucose cotransporter-2 inhibitor (SGLT2i) (GRADE: 2B)1
Sparsentan may be an appropriate first-line approach in contrast with the RASi-first approach as it1:
- Is a Dual Endothelin Angiotensin Receptor Antagonist (DEARA)
- Demonstrated greater proteinuria reduction and eGFR preservation in the
Phase 3 PROTECT trial compared with maximally tolerated irbesartan
The guideline notes that measures to reduce glomerular hyperfiltration and the impact of proteinuria may include combination therapy approaches, such as first-line sparsentan or ACEi/ARB used together with an SGLT2i.1 Immunomodulation therapy should also be considered simultaneously as necessary.1
Preventing or reducing immune complex-mediated injury
Treatments that lower pathogenic forms of IgA are recommended in combination with anti-inflammatory and/or antifibrotic therapies:
- A 9-month course of Nefecon is suggested (GRADE: 2B)1
- If Nefecon is unavailable, a limited course of a reduced-dose systemic glucocorticoids combined with antimicrobial prophylaxis is suggested (GRADE: 2B)1
Special situations, such as IgA nephropathy with nephrotic syndrome, acute kidney injury, rapidly progressive disease, pregnancy, or pediatric presentation, are addressed in detail in the full guideline.1
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Footnotes
This publication was not funded by Travere Therapeutics, Inc.
ACEi, angiotensin-converting enzyme inhibitor; ARB, angiotensin II receptor blocker; DEARA, Dual Endothelin Angiotensin Receptor Antagonist; eGFR, estimated glomerular filtration rate; GRADE, Grading of Recommendations Assessment, Development, and Evaluation; IgAN, immunoglobulin A nephropathy; IgAV, immunoglobulin A vasculitis; KDIGO, Kidney Disease: Improving Global Outcomes; MEST-C, mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis, tubular atrophy/interstitial fibrosis, and crescents; RASi, renin-angiotensin system inhibitor; SGLT2i, sodium-glucose cotransporter-2 inhibitor.
- Kidney Disease: Improving Global Outcomes (KDIGO) Glomerular Diseases Work Group. Kidney Int. 2025;108(Suppl 4S):S1-S71.
- Guyatt GH et al. J Clin Epidemiol. 2011;64:380-382.
MA-SP-25-0174 | November 2025