Division of Pediatric Hematology/Oncology, Department of Pediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
Department of Hematology, University Hospital/Inselspital Bern and University of Bern, Bern, Switzerland.
Hamostaseologie. 2019 Nov;39(4):404-408. doi: 10.1055/s-0039-1679929. Epub 2019 Mar 20.
Essential thrombocythemia is a chronic myeloproliferative neoplasm. It is extremely rare in children below 15 years of age with an estimated annual incidence of only 0.09 per million. Usually, clinical symptoms associated with essential thrombocythemia are mild or absent.
Here, we present the case of a 14-year-old female patient fulminantly presenting with acute symptoms comprising visual impairment, palmar and plantar stabbing pain. Blood count revealed massive thrombocytosis of 2373 × 10/L. Bone marrow morphology showed elevated numbers of mature megakaryocytes. Von Willebrand factor activity/antigen ratio was significantly reduced compatible with an acquired Von Willebrand syndrome associated with high platelet counts. Molecular analyses for driver mutations of myeloproliferative neoplasms including , were negative. Acute therapy comprising hyperhydration and oxygen supply complemented by acetylsalicylic acid led to amelioration of symptoms. Medication with hydroxycarbamide maintained a significant reduction of platelet counts but had to be reduced or withheld several times due to neutropenia. Repeated bleeding episodes observed in the course were clearly associated with increases in platelet counts above 1200 × 10/L explained by acquired von Willebrand syndrome. Sixteen months after diagnosis, therapy was switched to pegylated interferon and platelet counts could be stabilized without significant side effects.
特发性血小板增多症是一种慢性骨髓增殖性肿瘤。在 15 岁以下的儿童中极为罕见，估计年发病率仅为每百万分之 0.09。通常，与特发性血小板增多症相关的临床症状较轻或不存在。
这里，我们报告了一例 14 岁女性患者的暴发性病例，表现为急性症状，包括视力障碍、手掌和足底刺痛。血常规显示血小板计数高达 2373×10/L。骨髓形态学显示成熟巨核细胞数量增加。血管性血友病因子活性/抗原比值显著降低，符合与高血小板计数相关的获得性血管性血友病综合征。包括 在内的骨髓增殖性肿瘤驱动突变的分子分析为阴性。急性治疗包括水化和供氧，辅以阿司匹林，症状得到改善。羟基脲治疗可显著降低血小板计数，但因中性粒细胞减少而多次减少或停药。在病程中观察到的反复出血事件明显与血小板计数超过 1200×10/L 有关，这可由获得性血管性血友病综合征解释。诊断后 16 个月，改为聚乙二醇干扰素治疗，血小板计数可稳定，无明显副作用。
