Factors predicting progression of IgA nephropathies

Area of Science:

• Nephrology
• Immunology
• Pathology

Background:

• Defining the natural history of primary IgA nephropathy (IgAN) is challenging due to patient variability, differing lesion classifications, and statistical methods.
• Long-term studies reveal a wide range of progression rates (5-25% at 10 years, 25-50% at 20 years) and complete remission (5-30%).
• Geographic variability exists, partly explained by referral patterns.

Purpose of the Study:

• To identify key factors predicting the progression of IgA nephropathy.
• To elucidate the prognostic value of clinical and histological features in IgAN.
• To understand the role of proteinuria, blood pressure, and renal damage in long-term outcomes.

Main Methods:

• Multivariate statistical analyses, including Cox regression, were employed.
• Long-term natural history data from patient cohorts were analyzed.
• Clinical data (creatinine, blood pressure, proteinuria, hematuria) and histological features (glomerular sclerosis, interstitial fibrosis, crescents) were assessed.

Main Results:

• Advanced renal damage markers (increased creatinine, hypertension, nephrotic proteinuria) predict progression.
• Proteinuria and mean blood pressure during follow-up are independent predictors of end-stage CKD.
• Severity of glomerular sclerosis and interstitial fibrosis are strong histological predictors.
• The association of crescents with tuft adhesions is a significant risk factor, unlike crescents alone.

Conclusions:

• Proteinuria and mean blood pressure during follow-up are crucial independent predictors of IgA nephropathy progression and CKD.
• Histological features like glomerular sclerosis and interstitial fibrosis severity are vital prognostic indicators.
• While crescents can be a risk factor, their association with other features like tuft adhesions is more predictive.