Longitudinal Cohort of Pediatric Primary Immune Thrombocytopenia (ITP)

Study Overview
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Brief Summary
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Immune thrombocytopenic purpura (ITP) is a kind of rare childhood disease that involve autoimmune destruction of platelets.The current Pediatric ITP cohorts are mostly based on single-center or multi-center cases, or cohorts with limited sample size in China. There is a lack of comprehensive and large-scale prospective cohort studies in pediatric ITP. The purpose of this study is to analyze the clinical characteristics of Pediatric ITP, the treatment methods, prognosis and prognostic model of these patients in China.

Detailed Description
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Immune thrombocytopenia (ITP) is an organ-specific autoimmune disease, which is characterized by decreased platelet count and skin and mucosal bleeding. ITP is a kind of disease with increased platelet destruction and impaired platelet production caused by autoimmunity. Conventional treatment of adult ITP includes first-line glucocorticoid and immunoglobulin therapy, second line TPO and TPO receptor agonist, splenectomy and other immunosuppressive treatments (such as rituximab, vincristine, azathioprine, etc.). ITP is one of the most common hemorrhagic diseases. At present, the treatment response of ITP is not good, and a considerable number of patients need drug maintenance treatment, which seriously affects the quality of life of patients and increases the economic burden of patients. Longitudinal Cohort allows to describe the long-term clinical characteristics of pediatric ITP patients, to study the benefit-risk balance of treatments, including the growing development of targeted therapies and to analyze the prognostic factors and attempts to establish prognostic models. The study will include pediatric patients diagnosed with primary immune thrombocytopenia in the investigating hospitals, and collect basic information, diagnostic and treatment information from medical records. The study will use questionnaire to measure the exposure of patients, and prospectively follow-up to collect the prognosis information.

Official Title
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Clinical Characteristics, Prognosis and Prognostic Model of Pediatric Immune Thrombocytopenia: a Prospective, Multicenter, Observational Cohort Study

Conditions
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Primary Immune Thrombocytopenia

Intervention / Treatment
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* Other: data collection


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 6-17 years old (including both ends), male and female; Diagnosis of ITP. Exclusion Criteria: Secondary thrombocytopenia caused by various reasons, such as connective tissue disorders, bone marrow hematopoietic failure disease, myelodysplastic syndrome, malignancy, drugs, inherited thrombocytopenia, common variable immune deficiency, lymphoma, etc.; The expected follow-up period is less than 3 months.

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 17 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pediatric Primary Immune Thrombocytopenia<br>Immune thrombocytopenia (ITP) : defined according to the international working group criteria | Other: data collection<br>* The study will collect basic information, diagnostic and treatment information from medical records and use questionnaire to measure the exposure of patients, and prospectively follow-up to collect the prognosis information.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall response rate | Overall response rate defined as proportion of subjects with a platelet count ≥ 30 × 10^9/L and at least 2-fold from baseline without bleeding | 3 years | 
| Time to onset response | Time to onset response defined as the time needed for subjects to have a platelet count ≥ 30 × 10^9/L and at least 2-fold from baseline without bleeding | 3 years | 
| Duration of response | Duration of response defined as the longest duration for which the subject sustained a platelet count ≥ 30 × 10^9/L and at least 2-fold from baseline without bleeding | 3 years | 
| Sustained response rate | Sustained response rate defined as proportion of subjects who keep a platelet count ≥ 30 × 10^9/L and at least 2-fold from baseline without bleeding at 6, 12, 24, 36 months after initial administration of certain treatment in absence of rescue therapy | 3 years | 
| Emergency treatment | Percentage of subjects who received emergency treatment after initial administration of certain treatment | 3 years | 
| Number of subjects with clinically significant bleeding as assessed using the bleeding scale for pediatric patients with ITP after initial administration of certain treatment | Changes of the subjects' numbers in bleeding score after administration of certain treatment according to the reported bleeding scale for pediatric patients with ITP. The bleeding scale for pediatric patients with ITP is a measure of bleeding severity with the following grades: Grade 1 (minor) Minor bleeding, few petechiae (≤100 total) and/or ≤5 small bruises (≤3 cm in diameter), no mucosal bleeding；Grade 2 (mild) Mild bleeding, many petechiae (>100 total) and/or >5 large bruises (>3 cm in diameter), no mucosal bleeding；Grade 3 (moderate) Moderate bleeding, overt mucosal bleeding, troublesome lifestyle；Grade 4 (severe) Severe bleeding, mucosal bleeding leading to decrease in Hb>2 g/dL or suspected internal hemorrhage； | 3 years | 
| Number of subjects with clinically significant bleeding as assessed using the world health organization (WHO) bleeding scale after initial administration of certain treatment | Changes of the subjects' numbers in WHO bleeding score after administration of certain treatment according to the reported World Health Organization's Bleeding Scale. The WHO Bleeding Scale is a measure of bleeding severity with the following grades: grade 0 = no bleeding, grade 1= petechiae, grade 2= mild blood loss, grade 3 = gross blood loss, and grade 4 = debilitating blood loss. | 3 years | 
| Recurrence-free survival rate | Time from the start of treatment to the occurrence of a relapse or death event | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence | The incidence of pediatric primary immune thrombocytopenia in China will be described | 3 years | 
| Distribution | The population characteristics of pediatric primary immune thrombocytopenia in China will be described | 3 years | 
| Prognosis related factors selected from transcriptome data | The prognosis related factors will be selected from transcriptome data and be used to establish prognosis prediction model | 3 years | 
| Prognosis related factors selected from proteomics data | The prognosis related factors will be selected from proteomics data and be used to establish prognosis prediction model | 3 years | 
| Prognosis related factors selected from metabolomics data | The prognosis related factors will be selected from metabolomics data and be used to establish prognosis prediction model | 3 years | 
| Prognosis related factors selected from microbiome data | The prognosis related factors will be selected from proteomics data and be used to establish prognosis prediction model | 3 years | 
| Incidence, severity, and relationship of treatment emergent adverse events after treatment | Incidence, severity, and relationship of treatment emergent adverse events after treatment will be analyzed | 3 years |