Clinical Research Directory

Inclusion Criteria: * Minor patients aged 2 to 18 recruited at the Children's Hospital, in the service of Prof. Y. PEREL, Dr. N. ALADJIDI, CEREVANCE, * Adult patients (\> 18 years old) recruited at the Haut-Lévêque hospital, Pr JL PELLEGRIN, Pr JF VIALLARD, GECAI, * Patient with acute Immune thrombocytopenic purpura, seen at initial diagnosis or within 8 days (defined as thrombocytopenia \<100 G / L, after an infectious cause, drug or related to autoimmune disease, hematological malignancy or deficit Immune have been eliminated, Rodeghiero criteria, 2009). * Patient who received immunoglobulins more than 4 weeks before inclusion * Written consent given by the patient, if he is of age, or by the person (s) having parental authority * Patient affiliated or beneficiary of a social security scheme Exclusion Criteria: * Patient who has received specific treatment from an Immune thrombocytopenic purpura * Patient with secondary Immune thrombocytopenic purpura (hematological malignancy, autoimmune disease, immunodeficiency, pregnancy) * Patient placed under the protection of justice