HPA Antibodies and the Distribution of Antigen and Antibodies

Study Overview
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Brief Summary
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By detecting platelet antibodies of participants and then further to identify their genotype and analyzing laboratory examination, the investigators will obtain positive frequency of HPA antibodies, the distribution of HPA antigen and antibodies, effect of matching platelet transfusion, all of which in favor of draw a conclusion that it is very important to carry out HPA antibody detection and matching transfusion in early phase.

Detailed Description
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The investigators will detect platelet antibodies of participants who are according with the inclusive criteria. For participants with platelet antibodies, the investigators should screen out cases owning HPA antibodies and further to identify their genotype. Platelet infusion of same type will be applied to half of participants with HPA antibodies as experimental group, and the another half of participants with hematopathy will be infused ordinary platelets as control. The investigators will estimate the effect of matching transfusion through laboratory examination such as platelet count 1 hour and 24 hours after transfusion and clinical feature comparing to control group. Finally, the investigators will obtain several conclusions includes positive frequency of HPA antibodies, the distribution of HPA antigen and antibodies, effect of matching platelet transfusion by analyzing a bunch of relevant information. So, strong evidence will be provide to decide if it is very important to carry out HPA antibody detection and matching transfusion in early phase.

Official Title
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Multi-center Study in the Frequency of HPA Antibodies and the Distribution of Antigen and Antibodies in Chinese Blood Disease Patients

Conditions
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Blood Disease, Platelet Refractoriness, Antibody-mediated Rejection

Intervention / Treatment
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* Procedure: same type infusion of main HPA antigen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Blood disease patients with voluntary participation in creating records, no gender limitation, 0-99 years of age, first diagnosed or be hospitalized in our hospital with platelet transfusion more than once. Patients transfers from other hospitals which can be confirm the time (>1) of platelet transfusion. Patient be cured, discharged or dead with the time of platelet transfusion is between 1 to 10 should be included. Patient with HPA antibodies at admission could be considered to be included into same type transfusion group. - Exclusion Criteria: Patients informed but refuse to participate in; Patients with HPA antibodies quitting therapy or breaking off cooperation during research; Patients with many referrals and the time of platelet transfusion can not be confirmed; Patient without platelet transfusion; Patient with termination of treatment whatever active or passive. -
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: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: HPA antigen and antibodies<br>Investigate the positive rate of HPA antibodies, the distribution and the specificity of HPA antigen and antibodies in Chinese blood disease patients. | |
| No Intervention: necessity of HPA antibodies screening<br>Investigate the connection between times of platelet transplantation and HPA antibody titer, which providing statistical data for evaluating the necessity and setting screening time and standards of HPA antibodies screening. | |
| Experimental: matched platlet infusion<br>Enable platelet donors'common HPA antigen to be typed and blood disease patients to be same type infusion of main HPA antigen as possible as early.The investigators compare the differences of platelet count between patients with same type infusion of main HPA antigen and not. | Procedure: same type infusion of main HPA antigen<br>* Compare the differences of platelet count between participants with same type infusion of main HPA antigen and not<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The percentages (%) of hematopoietic patients with anti-HPA antibodies among all investigated hematopoietic patients who need long-term infusion of platelets. | The investigators will recruit about 25000 participants in total (anticipated) of different hospitals spread over the whole country and divide them into two categories, patients with and patients without platelet antibodies, by detecting antibodies through solid-phase agglutination (qualitative analysis). The investigators screen out the positive ones and then distinguish participants with antibodies against human platelet antigens (HPA) from those with antibodies against human leukocyte antigens (HLA) by using LIFECODES PAKPLUS (qualitative analysis). At the same time, subtype of anti-HPA antibodies (such as anti-HPA-1a antibodies) are detected. The analyzation of large sample data will present investigators the most important findings, the percentages (%, the primary outcome measure) of hematopoietic patients with anti-HPA antibodies (include the total and the various subtypes) among all investigated hematopoietic patients who need long-term infusion of platelets. | From one participant first enrolled in this study to the moment of HPA antibodies could be detected or death, up to 6 months. The investigators will calculate the percentages after all participants are done with trace. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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HPA, Blood disease