Purpose: Despite not yet explored, the serum lactate dehydrogenase (LDH) level in hemoglobinopathy SC (HbSC) patients could be a marker of disease severity as this association is strong in sickle cell patients. We hypothesized that the degree of hemolysis in HbSC patients is a key determinant influencing a spectrum of complications that reflect the severity of HbSC vasculopathy. The aim of this study was to analyze the associations between hemolytic parameters and chronic complications in adult SC patients. Findings: We demonstrated that LDH reflects the overall rate of hemolysis and presents a correlation with the complications related to the hemolytic subphenotype: retinopathy, venous thromboembolism and leg ulcers in HbSC patients. Remarkably, this simple biomarker was associated with a clinical subphenotype of complications in patients with HbSC disease. Conclusions: We propose that LDH elevation identifies HbSC patients with hemolysis, which could be a marker of endothelial dysfunction and end-organ vasculopathy. The use of this test as a marker of disease severity could complement the decisions taken during HbSC patient management. (C) 2016 Elsevier Inc. All rights reserved.59 119123