Prognostic Factors of Acute Splenic Sequestration

Study Overview
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Brief Summary
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Acute splenic sequestration is a frequent and life threatening complication occurring in approximately 10 % of homozygous children. Maximal incidence is between 6 and 18 months. The investigators formulate the hypothesis that there are clinical, biological and genetic markers predictive of severe complications notably acute splenic sequestration in SCD children. The present research project thus aims at analyzing in a forward-looking way the profile of severity by analysing clinical, biological and genetic characteristics in a multicentric cohort of 60 SCD children

Detailed Description
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A prospective multicentric analysis will be conducted in a cohort of 150 SS or S ß ° children diagnosed at birth, included at 3 -5 months and followed up to the age of 24 months. Five visits, superimposed to the usual follow-up of SCD children, (Recommendations of the High Authority of Health) at 3 months, 6 months, 12 months, 18 months and 24 months will allow a clinical evaluation and an additional sampling of blood (5 mL) at each visit. The samples will allow 1.analysis of the red blood cell phenotype (adhesion and deformability) and densities 2. the genetic profile 3.to establish a cell bank, a sera bank and a DNA bank, Spleen function in the cohort will be estimated by spleen scintigraphy, coupled with blood markers (pitted cells, Howell-Jolly bodies counts)

Official Title
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Study of Prognostic Factors of Acute Splenic Sequestration in a Cohort of Sickle Cell Disease (SCD) Children Diagnosed at Birth

Conditions
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Anemia; Drepanocytic

Intervention / Treatment
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* Procedure: blood samples and scintigraphy


Participation Criteria
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Eligibility Criteria
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Inclusion criteria : Children aged 3 to 6 months homozygous (SS) or S beta° sickle cell disease diagnosed by neonatal screening With no history of acute splenic sequestration Signed parental consent Patient covered by national insurance scheme or CMU Exclusion criteria : Children with other SCD genotype Children with congenital anatomical asplenia Children with previous episode of acute splenic sequestration Absence of possible follow-up Simultaneous enrolment in another biomedical research

Ages Eligible for Study
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Minimum Age: 3 Months
Maximum Age: 6 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Intervention<br> | Procedure: blood samples and scintigraphy<br>* at 3 months, 6 months, 12 months, 18 months and 24 months will allow a clinical evaluation and an additional sampling of blood of 5 mL at each visit Scintigraphy at 6 months and 18 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Study of prognostic factors of acute splenic sequestration | Complete blood count, reticulocyte count, haemoglobin level, VGM, TGMH, CCMH, hematocrit, % foetal haemoglobin (HbF), red blood cell densities (2 mL) Deformability of red blood cells Expression study of the cell surface molecule: Phosphatidyl serine, CD 36, READ B-CAM, CD 47, ICAM 4, VLA 4. (Cellulotheque = red blood cells frozen in cryopreservative conditions) Total LDH, Bilirubine (stigmas of hemolysis) Genetic Profil ( DNAtheque) | after three years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Study of hematology parameters | Percentage of Howell Jolly's bodies (0,1 mL) Percentage of pitted cells (0,5 mL fixed in 4 %)formaldehyde Splenic volume, semi-quantitative measure in scintigraphy Antibody titers in answer to the antipneumococcic vaccination ( serotheque) | after three years |