Study of a Deformability Parameter of Red Blood Cell
- Conditions
- Drepanocytosis
- Interventions
- Procedure: basal blood collectionProcedure: blood collection M6Procedure: blood collection M12
- Registration Number
- NCT05850156
- Lead Sponsor
- Assistance Publique Hopitaux De Marseille
- Brief Summary
Sickle-cell disease is one of the most common severe monogenic disorders in the world, it results in the synthesis of abnormal hemoglobin (HbS) instead of hemoglobin A. When deoxygenated, the sickle haemoglobin (HbS) polymerizes inducing the sickling of red blood cells (RBCs) and leading to decreased deformability and increased fragility. Therefore, sickle RBCs exhibit a reduced lifespan associated with intravascular hemolysis, hemolytic anemia and low tissue oxygenation. Sickle RBCs, which exhibit abnormal adhesive properties to endothelial cells, can block the microcirculation, causing the occurrence of painful vaso-occlusive crisis (VOC), acute chest syndrome (ACS), acute and chronic organ damage (heart, lung, liver, spleen, kidney, bone...) and shortened life span.
A preliminary study performed on RBC from sickle cell patients (Hb SS) has shown an alteration of a parameter measuring the overall deformability of RBCs by evaluating the nature of their movement in a shear flow. This parameter is significantly lower in sickle cell patients in steady state compared to a population of healthy individuals. The parameter is also significantly lower in sickle cell patients during VOC when compared to patient in steady state.
The main objective of this study is to evaluate the performance of the method for measuring the deformability of RBCs on an experimental prototype. Measurements will be performed on blood samples from subjects with a normal hemoglobin electrophoretic profile, from heterozygous carriers of sickle cell disease and from patients with sickle cell disease. Samples from paediatric patients will also be tested to study any specificity in comparison to adult subjects.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 130
- Repeatability of ftt (mechanical marker of deformability) measurements
- Effect of ambient temperature on ftt measurements
- Effect of sample processing time on ftt measurements
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Adult sickle cell patients blood collection M12 In the context of routine care, 3 blood collection will be performed on adult sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. pediatric sickle cell patients blood collection M6 In the context of routine care, 3 blood collection will be performed on pediatric sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. Adult sickle cell patients basal blood collection In the context of routine care, 3 blood collection will be performed on adult sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. Adult sickle cell patients blood collection M6 In the context of routine care, 3 blood collection will be performed on adult sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. pediatric sickle cell patients blood collection M12 In the context of routine care, 3 blood collection will be performed on pediatric sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. Adult sickle cell carriers (heterozygous patients) basal blood collection In the context of neonatal screening for sickle cell disease, the parents will be called altogether with their children in order to check if they are sickle cell carriers or not. Only 1 blood collection will be performed for this group. pediatric sickle cell patients basal blood collection In the context of routine care, 3 blood collection will be performed on pediatric sickle cell patients for the analysis of hemoglobin fractions. For each blood collection, an additional volume of blood will be taken for the research purposes. Control patients basal blood collection In the context of neonatal screening for sickle cell disease, the parents will be called altogether with their children in order to check if they are sickle cell carriers or not. Only 1 blood collection will be performed for this group.
- Primary Outcome Measures
Name Time Method repeatability of fTT measurements 14 months A series of 10 measurements of a deformability of red blood cells parameter (fTT) on the same blood sample will be performed successively within 24 hours for 4 samples (2 from sickle cell patient and 2 from control or heterozygous patients). The repeatability of the measurements will be determined from these measurements and the effect of a variation in the total number of red blood cells will be analyzed.This study will be reproduced on several blood samples and the measurements will be repeated under the same conditions 24 hours later.
- Secondary Outcome Measures
Name Time Method Correlation of ftt with the collected data 14 months A correlation study of ftt with socio-demographic (age and sex), biological (results of hemogram and hemoglobin electrophoresis) and clinical (number of vaso-occlusive crises and treatment with Hydroxyurea) will be conducted.
Effect of ambient temperature during fTT measurement 14 months Tests will be conducted to evaluate the effect of ambient temperature on the measurement of a series of 4 samples at ambient temperature (from 18 to 30°C).
Effect of the processing time on fTT measurement 14 months test will be conducted to measure the fTT on a series of 10 samples, twice a day during the 2 first days an then every day for 5 days.