Abstract
Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) have become recently useful as predictive and prognostic tools in patients with various medical conditions.
To evaluate NLR and PLR in systemic lupus erythematosus (SLE) and their relation to disease clinical characteristics, nephritis, disease activity and damage.
The study involved 110 Egyptian SLE patients; 80 with lupus nephritis (naive and relapsing) and 30 without as well as 50 matched control. Patients were subjected to full clinical examination, SLE disease activity index (SLEDAI) scoring, and damage using Systemic Lupus International Collaborating Clinics Damage Index (SLICC-DI). Laboratory and immunology profiles included the complete blood count (CBC) with differential white blood cell counts and estimation of both NLR and PLR, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), protein/creatinine ratio, anti-nuclear antibody (ANA), anti-double stranded deoxyribonucleic acid (anti-dsDNA), serum complements and interleukin-6 (IL-6) levels.
Both NLR and PLR were significantly higher in SLE patients (4.8 ± 1.4 and 281.7 ± 66.7 respectively) compared to controls (3.8 ± 2 and 138.2 ± 50.4). Both ratios were significantly elevated in patients with active lupus nephritis (at presentation or as a flare) and were comparable between naive and relapsing lupus nephritis patients. In lupus nephritis patients, NLR and PLR significantly correlated with proteinuria, ESR, hypocomplementemia, IL6, SLEDAI and SLICC-DI. The best NLR cut-off value to predict nephritis activity was 5.65, whereas the best PLR cut-off value was 316.5.
NLR and PLR appear to be potentially useful cheap parameters of activity, relapse and severity in SLE patients with nephritis.