Aim of the workTo investigate the value of neutrophil- lymphocyte ratio (NLR), platelet- lymphocyte ratio (PLR), red blood cell distribution width (RDW), mean platelet volume (MPV) as biomarkers of disease severity and clinical manifestations in systemic sclerosis (SSc). Patients and methodsThis study included 35 SSc patients, together with 45 controls. Disease severity was assessed by Medsger severity score (MSS). NLR, PLR, MPV, RDW were measured by COULTER LH 750 assay analyzer. ResultsThe mean age of SSc patients and controls was 42.8 ± 12.6 and 40.8 ± 9.7 years respectively. MPV, RDW, NLR, PLR were significantly higher in patients compared to controls (p = 0.03, < 0.001, <0.001, 0.02). NLR, PLR were significantly higher in patients presenting with myositis (p = 0.002, 0.004), and proximal muscle weakness on MSS (p = 0.009, 0.02). NLR was significantly higher in patients with severe peripheral vascular ischemia (p = 0.02). RDW was significantly higher in patients with higher general MSS (p = 0.03) NLR, PLR were significantly positively correlated with severity of muscle weakness (p = 0.001, 0.004), RDW was significantly associated with general MSS (p = 0.002). NLR and PLR were the valuable predictors of muscle involvement (p = 0.003, 0.005) and severity of muscle weakness (p = 0.001, 0.003). ConclusionMPV, RDW, NLR, PLR were significantly higher in SSc patients suggesting their role as biomarkers reflecting the enduring inflammatory process in SSc. Increased NLR and PLR were related to muscular involvement, and severity of muscular weakness. Increased NLR predicted severity of peripheral vascular ischemia and elevated RDW predicted general severity, MPV did not predict severity or disease manifestations of SSc.