Essential Thrombocythemia in Childhood

Abstract

In addition to the criteria of the Polycythemia Vera Study Group, positive markers for essential thrombocythemia (ET) include spontaneous BFU-E, splenomegaly, and megakaryocyte morphology in bone marrow smears and biopsy material. The hematologic features of 11 reported cases of ET in childhood showed platelet counts in excess of 1000 x 10(9)/L in all, slight leukocytosis in 8, and splenomegaly in 9. The presenting thrombohemorrhagic manifestations in 8 symptomatic cases were microcirculatory disturbances and transient neurologic ischemic attacks in 2, recurrent mucocutaneous bleedings in 6, and priapism in 1. There are no reports of ET in childhood complicated by microcirculatory disturbances at platelet counts below 1000 x 10(9)/L. Anagrelide and alpha-interferon, which are non-leukemogenic agents for the reduction of platelet counts, may become the treatment of choice in childhood ET. Anagrelide is tolerated better than alpha-interferon. The potential leukemogenic drugs hydroxyurea and busulfan should be used cautiously and withheld as long as possible.

Essential thrombocythaemia in children

“…As previously discussed, ET in children is not always a benign entity; the crucial question is how to identify patients who are at high risk of complications and need treatment. Most laboratory tests are of little help in predicting the clinical course of ET (Barbui et al , 1983; Michiels & Van Genderen, 1997). Occasional studies in adults (Fenaux et al , 1990), however, have shown a correlation between increased risk of haemorrhage if the platelet count is > 2000 × 10 9 /l.…”

Features of essential thrombocythaemia in childhood: a study of five children

“…However, with the advent of automated platelet counting, increased platelet counts and, in particular, ET are diagnosed with increasing frequency in young adults and even in childhood, although less commonly than in adults. The 11 cases of ET in children reported in the literature ( Michiels & Van Genderen, 1997) showed persistently elevated platelet counts over 1000 × 10 9 /l with thrombotic and haemorrhagic episodes occurring in eight out of 11 patients.…”

Cytogenetic and Molecular Genetic Aspects of Childhood Myeloproliferative/Myelodysplastic Disorders

“…Cases and reviews of cases reported in the literature indicate that the natural history, certainly in ET and PV, may be similar to that seen in adults [6, 9, 10]. The UK Childhood Myeloproliferative Diseases Registry will try to ascertain the incidence and natural history of these disorders in childhood.…”