Correlation Between C4/IgG with Macroproteinuria in Chronic Kidney Disease: A Pilot Study

Area of Science:

• Nephrology
• Immunology
• Biochemistry

Background:

• Proteinuria, particularly macroproteinuria, is linked to immunoglobulin G (IgG) loss.
• The complement system plays a role in kidney diseases that cause proteinuria.
• The association between complement and IgG ratios and macroproteinuria is not well understood.

Purpose of the Study:

• To investigate the relationship between complement C4/IgG ratio and macroproteinuria in chronic kidney disease (CKD) patients.
• To identify potential predictive biomarkers for macroproteinuria.

Main Methods:

• 1013 non-dialysis CKD patients were analyzed, with 268 undergoing kidney biopsy.
• Biomarkers were compared across CKD and proteinuria groups using ANOVA and t-tests.
• Correlation and binary logistic regression analyses identified factors influencing macroproteinuria, and ROC curves assessed predictive value.

Main Results:

• Complement C4 levels were higher in patients with macroproteinuria and positively correlated with proteinuria.
• The C4/IgG ratio was identified as an independent predictor of macroproteinuria, alongside gender, age, and diabetes history.
• ROC curve analysis demonstrated the predictive capability of the C4/IgG ratio for macroproteinuria, with specific cut-off values yielding significant sensitivity and specificity.

Conclusions:

• The complement C4/IgG ratio serves as a potential predictor for macroproteinuria in CKD patients.
• This ratio may aid in assessing kidney disease progression and identifying patients at risk for significant proteinuria.