The relationship between neutrophil-lymphocyte ratio and early renal affection in patients with lupus nephritis

Lupus nephritis (LN) remains one of the most severe manifestations of systemic lupus erythematosus, driven by immunecomplex deposition, complement activation, and persistent glomerular inflammation. Renal involvement develops in approximately 30.5% of SLE patients and significantly influences long-term morbidity and mortality. Early detection of renal injury is essential, yet conventional markers such as serum creatinine and proteinuria may not capture early inflammatory changes. The neutrophil-lymphocyte ratio (NLR), a simple and inexpensive marker derived from routine blood counts, reflects the combined effects of neutrophilia and lymphopenia associated with systemic inflammation. NLR correlates with classical inflammatory biomarkers including CRP, ESR, IL-6, and TNF-α, and is influenced by heightened neutrophil activation, impaired lymphocyte regulation, and cytokine-driven immune dysregulation characteristic of LN. The aim of this review is to evaluate the relationship between NLR and early renal affection in lupus nephritis, highlighting its pathophysiologic basis, its association with renal activity and fibrosis, and its potential utility as a predictive marker for early renal involvement.