Heart Arteries and Sickle Cell Disease / Coeur Artères DREpanocytose

Sickle cell disease (SCD), one of the lost common genetic diseases worldwide, is caused by a mutation in the β globin gene. Most patients with this disease are homozygous for the βS allele (SS), whereas others have inherited a βS allele with another mutation in the β globin gene. In addition to repeated acute ischemic insults due to the red blood cells sickling in the microcirculation, a chronic vasculopathy leads to organ injuries, such as kidney disease, stroke, pulmonary hypertension, retinopathy, bone infarcts, and leg ulcers. CADRE is a multinational prospective observational study undertaken in five countries in sub-Saharan Africa. Patients with SCD will be recruited through outpatients' clinics in public, university and private hospitals and research centers in five countries. The CADRE protocol was approved by the relevant national ethics committee in each of the participating countries. Primary endpoint is to measure the prevalence and the incidence of the main vascular complications in the main types of SCD: glomerulopathy, nephropathy, cardiopathy, pulmonary hypertension, retinopathy, strokes, osteonecrosis and leg ulcers. Secondary endpoints are: * to define the clinical and biological predictors of SCD vasculopathy in Africa * to search for genetic risk factors for the SCD-related cardiovascular complications, in particular alpha thalassemia, persistence of foetal hemoglobin and other candidate genetic polymorphisms * to search for functional risk factors (pulse wave velocity, capillary vasodilatation, blood visosity) for the SCD-related cardiovascular complications * to search for new biological determinant of SCD-related cardiovascular complications, in particular alternative markers of hemolysis (microparticules, free heme) and inflammation (cytokines, leucocytes phenotyping, NET (neutrophile extracellular traps))