8 Acute autoimmune thrombocytopenia

Abstract

Childhood acute autoimmune thrombocytopenia is defined as a bleeding disorder in otherwise healthy children caused by transient destruction of platelets. It is benign, presenting mostly with skin purpura and minor bleeds. The diagnosis requires information about previous infections or immunizations, a physical examination looking for signs or symptoms for other causes of thrombocytopenia and a complete blood count with examination of the peripheral blood smear focusing on the number and morphology of platelets. Bone marrow examination is indicated only when in doubt and should be considered if prednisone therapy is planned. A threshold platelet count dividing high- and low-risk groups in immune thrombocytopenia (ITP) is not known because of problems with platelet counting in thrombocytopenia and the lack of clinical data. Immunoglobulins or glucocorticoids increase the platelet count, probably by blockage of the phagocytic monocyte-macrophage system. However, it is unclear whether this increase influences bleeding or mortality or whether the disadvantages of these medications might outweigh their benefits.