Concise semiquantitative histological scoring system for immunoglobulin A nephropathy

Area of Science:

• Nephrology
• Pathology
• Clinical Medicine

Background:

• Immunoglobulin A nephropathy (IgAN) is a common progressive glomerulonephritis with variable histological features.
• Histological findings in IgAN are crucial risk factors for predicting renal outcomes.
• A concise histological scoring system is needed for practical clinical application.

Purpose of the Study:

• To develop and validate a concise semiquantitative histological scoring system for IgAN.
• To establish prognostic and therapeutic indicators for IgAN patients based on histological findings.

Main Methods:

• A histological scoring system was developed using multivariate survival analysis.
• Data from 293 primary IgAN patients from two Chinese centers were analyzed.
• End-stage renal disease (ESRD) was used as the primary endpoint event.

Main Results:

• Four indices—extracapillary glomerular activity index (exGAI), mesangial proliferation index (MsI), glomerular chronicity index (GCI), and tubulointerstitial chronicity index (TCI)—independently predicted ESRD.
• A scoring system (Total I) was created by summing these indices.
• High scores on exGAI (≥4), GCI (≥4), MsI (≥2), and TCI (≥2) indicated increased risk of progression.
• An exGAI score of ≥4 identified patients who benefited from immunosuppressive therapy, showing a lower ESRD incidence.

Conclusions:

• The developed scoring system is a concise and valuable tool for IgAN prognosis.
• The scoring system provides important therapeutic indications for managing IgAN.
• This system can aid clinicians in risk stratification and treatment decisions for IgAN.