Treatment of IgA nephropathy and Henoch–Schönlein nephritis

Abstract

Treatment options for primary IgA nephropathy (IgAN) and Henoch–Schönlein nephritis are still largely based on opinion or weak evidence. Consequently, the recent KDIGO Clinical Practice Guidelines for Glomerulonephritis have assigned low levels of evidence for almost all recommendations and suggestions related to these two diseases. In this Review, we describe an algorithm for structuring the treatment of IgAN depending on the clinical scenario. Key to therapeutic decision making is assessment of the individual's prognosis. Clinical parameters (such as proteinuria, hypertension, and impaired glomerular filtration rate [GFR]) are used to estimate risk, but the clinical value of the novel histological Oxford-MEST classification remains to be determined. If these parameters indicate a risk of progressive GFR loss, comprehensive supportive care remains the mainstay of therapy. Two large trials, STOP-IgAN and TESTING, are underway to evaluate the value of adding corticosteroids after initiating such supportive care. At present, little evidence exists to suggest that any other immunosuppressive therapy beyond corticosteroids is effective in either IgAN or Henoch–Schönlein nephritis.

Key Points

  • Only a fraction of patients with IgA nephropathy require treatment in order to prevent or reduce progressive loss of glomerular filtration rate (GFR)

  • Proteinuria, hypertension and any evidence of established renal damage enable a relatively reliable estimation of patient risk

  • The 'low-risk' patient with minor urinary abnormalities, normal GFR and normotension requires regular follow-up only

  • The 'intermediate-risk' patient with 'significant' proteinuria, hypertension and/or a slow reduction in GFR (including those with an estimated GFR below 30 ml/min/1.73 m2) will benefit from comprehensive supportive care

  • Several ongoing studies will re-evaluate the role of systemic or enteric corticosteroids in 'intermediate-risk' patients

  • The 'high-risk' patient with a rapid loss of GFR may require more aggressive immunosuppression

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Figure 1: Suggested treatment algorithm for patients with primary IgAN depending on their initial presentation.

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Correspondence to Jürgen Floege.

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J. Floege declares an association with the following company: Pharmalink (consultant). J. Feehally declares no competing interests.

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Floege, J., Feehally, J. Treatment of IgA nephropathy and Henoch–Schönlein nephritis. Nat Rev Nephrol 9, 320–327 (2013). https://doi.org/10.1038/nrneph.2013.59

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