Characterization of early IgA nephropathy.

Area of Science:

• Nephrology
• Pathology
• Immunology

Background:

• Immunoglobulin A (IgA) nephropathy is a common cause of glomerulonephritis.
• Early clinical detection of IgA nephropathy is crucial for prognosis.
• Histological grading aids in understanding disease severity and progression.

Purpose of the Study:

• To correlate histological grading of early IgA nephropathy with long-term disease progression.
• To evaluate the predictive value of specific histological features for IgA nephropathy outcomes.
• To identify subsets of patients with minimal risk of disease progression.

Main Methods:

• Retrospective analysis of 45 patients with early IgA nephropathy.
• Correlation of clinical parameters (serum creatinine, proteinuria, hypertension) with histological findings.
• Application of a chronicity-based histological grading system and assessment of acute glomerular lesions.
• Long-term follow-up (median 123 months) to assess disease progression.

Main Results:

• Disease progression occurred in 44.4% of patients.
• Standard glomerular grading (GG1, GG2) did not correlate with progression.
• Subclassification of GG1 into GG1a (sclerosis <10%) identified a non-progressive disease group.
• Tubulointerstitial grade correlated with progression but had low sensitivity for non-progression.
• Hyaline arteriolosclerosis and acute glomerular lesions showed no correlation with progression.

Conclusions:

• Chronicity-based histological grading is applicable to early IgA nephropathy.
• GG1a subgroup signifies a very low risk of IgA nephropathy progression, representing genuine early disease.
• Histological assessment refines prognostication beyond initial clinical parameters.