# Investigation of the Relationship Between Neutrophil/Lymphocyte, Platelet/Lymphocyte, IgA/C3, IgA/C4, and C3/C4 Ratios and Proteinuria in Patients With Immunoglobulin A (IgA) Nephropathy

## TL;DR

This study explores how blood markers like NLR and IgA/C4 ratios relate to proteinuria in patients with IgA nephropathy, a common kidney disease.

## Contribution

The study identifies specific correlations between IgA/C4 ratio and proteinuria, suggesting new insights into IgA nephropathy.

## Key findings

- Proteinuria showed significant negative correlations with urine pH and IgA/C4 ratio.
- PLR correlated positively with C4 and negatively with IgA/C4 ratio.
- NLR and CRP did not show significant correlations with proteinuria.

## Abstract

Background

Immunoglobulin A nephropathy (IgAN) is the most common primary glomerular disease, characterized by IgA-containing immune complexes in the mesangium and mesangial cell proliferation. Proteinuria is a strong indicator of the progression of chronic kidney disease. This study aimed to evaluate the relationship between systemic inflammation markers, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), IgA/complement (C)3, IgA/C4, and C3/C4 ratios, and proteinuria in IgAN patients.

Methods

This retrospective study involved 38 patients diagnosed with IgAN between 2002 and 2011. We assessed various serum markers such as leukocyte count, NLR, PLR, C-reactive protein (CRP), C3, C4, IgA, and IgM, as well as proteinuria. The correlation between these markers and proteinuria was examined.

Results

The mean age of the patients was 37.8 ± 2 years, with 68.42% male. No significant correlation was found between the NLR and proteinuria (p=0.3) or CRP (p=0.3). However, a moderate positive correlation was observed between the NLR and sedimentation rate (R=0.38, p=0.07). Significant negative correlations were found between proteinuria and both urine pH (R=-0.5, p=0.002) and IgA/C4 ratio (R=-0.5, p=0.013). There were positive correlations between the PLR and C4 (R=0.45, p=0.02) and negative correlations between the PLR and IgA/C4 ratio (R=-0.56, p=0.003) and IgA/C4 and C3 (R=-0.48, p=0.008). No significant differences in proteinuria and leukocyte count were observed between the two sexes.

Conclusion

Although no significant relationship was found between the NLR, PLR, and proteinuria in IgAN, correlation between the IgA/C4 ratio and C4 warrants further investigations in larger studies.