OBS'CEREVANCE: French Cohort of Pediatric Autoimmune Cytopenia

Study Overview
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Brief Summary
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From 2004, OBS'CEREVANCE is a national real-world prospective clinical cohort of patients with auto-immune cytopenia of pediatric-onset : Immune thrombocytopenia (ITP), Autoimmune Hemolytic anemia (AIHA), or Evans syndrome (all bi or tri cytopenias). Thanks to the collaboration of the 30 French pediatric hematologic centers, this cohort supports all of the Rare Disease Centre CEREVANCE (Centre de Référence National des Cytopénies Auto-Immunes de l'Enfant) missions for care, education and research. Specifically, this original unbiased database allows to describe the long-term health of adult patients, to identify the heterogenous genetic underlying pathophysiologic contexts, and to study the benefit-risk balance of treatments, including the growing development of targeted therapies.

Detailed Description
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Immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AHAI) are rare childhood diseases that involve autoimmune destruction of platelets and erythrocytes respectively. They may be associated with an even rarer entity, Evans syndrome (ES). These three conditions are referred to as autoimmune cytopenias (AIC). In association with CAI, patients may present with various immunopathological (IM) manifestations such as lymphoproliferation, autoimmune autoimmune/autoinflammatory organ diseases that may be absent at the time of at the time of diagnosis of CAI and develop during follow-up. Since 2004, the CEREVANCE reference center for childhood autoimmune CEREVANCE has been coordinating a national prospective cohort of patients with pediatric-onset CAI including over 1900 patients (data 05/2023). Thanks to the collaboration of the 30 French pediatric hematologic centers, this cohort supports all of the Rare Disease Centre CEREVANCE (Centre de Référence National des Cytopénies Auto-Immunes de l'Enfant) missions for care, education and research. Specifically, this original unbiased database allows to describe the long-term health of adult patients, to identify the heterogenous genetic underlying pathophysiologic contexts, and to study the benefit-risk balance of treatments, including the growing development of targeted therapies.

Official Title
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French National Cohort of Patients With Pediatric-onset of Autoimmune Cytopenia (OBS'CEREVANCE Cohort)

Conditions
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Immune Thrombocytopenia, Autoimmune Hemolytic Anemia, Evans Syndrome

Intervention / Treatment
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* Other: data collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of ITP, AIHA, Evans Syndrome Onset before the age of 18 Exclusion Criteria: Opposition of legal representative or to data collection

Ages Eligible for Study
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Maximum Age: 17 Years

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Immune thrombocytopenia (ITP)<br>Immune thrombocytopenia (ITP) : defined according to the international working group criteria (Rodeghiero et al., Blood 2009). | Other: data collection<br>* description of the long-term health of adult patients, identification of the heterogenous genetic underlying pathophysiologic contexts, study of the benefit-risk balance of treatments, including the growing development of targeted therapies.<br>|
| Autoimmune Hemolytic anemia (AIHA)<br>Autoimmune haemolytic anaemia (AIHA) : Hb < 110 g/L with a positive direct antiglobulin test (DAT) and at least one of the following haemolysis criteria: reticulocyte count > 120 G/L, free bilirubin > 17 mmol/L, or haptoglobin < 10 mg/dL. | Other: data collection<br>* description of the long-term health of adult patients, identification of the heterogenous genetic underlying pathophysiologic contexts, study of the benefit-risk balance of treatments, including the growing development of targeted therapies.<br>|
| Evans syndrome (all bi or tri cytopenias)<br>Evans syndrome (ES) : simultaneous (less than 1 month) or sequential association of at least two autoimmune cytopenia among ITP, AIHA and autoimmune neutropenia (AIN). | Other: data collection<br>* description of the long-term health of adult patients, identification of the heterogenous genetic underlying pathophysiologic contexts, study of the benefit-risk balance of treatments, including the growing development of targeted therapies.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AIC context | Number of patients with immunopathological manifestations (IM), systemic erythematosus lupus (SLE), primary immunodeficiency (PID). | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Treatment lines | Percentage of patients with each treatment by line of treatments | every 6 months after baseline up to 19 years | 
| Adverse drug reactions | Percentage of patients with adverse drug reaction reported by investigators | every 6 months after baseline up to 19 years | 
| Events | Percentage of patients with other events of interest like cancer, infection, thrombosis, death | every 6 months after baseline up to 19 years | 
| AIC context | Number of patients with immunopathological manifestations (IM), systemic erythematosus lupus (SLE), primary immunodeficiency (PID). | every 6 months after baseline up to 19 years |