Thrombocytosis in Children and Adolescents: Does This Need Separate Approach? - A Review

Abstract

In childhood inflammation and infection, secondary thrombocytosis is frequent finding. Primary thrombocytosis is often hereditary and may occur due to germline mutations in genes which encode key thrombopoiesis regulators such as receptor’s effector kinase Januskinase2 (JAK2), thrombopoietin (THPO) or receptor c-MPL. Additionally, somatic mutations within MPL, JAK2 and calreticulin (CARL) may act as driver mutations in Philadelphia – negative myeloproliferative neoplasms including polycythemia vera, essential thrombocythemia and primary myelofibrosis. Enhanced and detailed knowledge on clinical complications and molecular mechanisms are such disease are echoed by recommendations of European LeukemiaNet (ELN) and World Health Organization diagnostic criteria on adult myeloproliferative neoplasms. Although data on thrombocytosis in children is rare and does not contain any guidelines for thrombocytosis in pediatric age group. Additionally, complications according to age and specificity of pharmacology advise that recommendations personalized to children population is essential in routine practice. In this review, we recapitulated literature related to classification, diagnostic modalities, and management of thrombocytosis in children.