Jones Catherine, Levy Yair, Tong Alex W
Department of Hematology/Oncology, Baylor Charles A Sammons Cancer Center, Dallas, Texas, USA.
Department of Clinical Oncology Research, Baylor Charles A Sammons Cancer Center, Dallas, Texas, USA.
BMJ Case Rep. 2014 Dec 1;2014:bcr2014205663. doi: 10.1136/bcr-2014-205663.
Polycythaemia vera (PV) is a clonal disorder of bone marrow stem cells characterised by erythrocytosis. Diagnosis of PV requires exclusion of secondary causes of polycythaemia. It has been held that an elevated erythropoietin (Epo) level strongly indicates secondary erythrocytosis and excludes PV diagnosis, to the extent that the reduced serum Epo level is currently listed as a minor criterion in the WHO classification scheme for PV. However, patients with PV who co-present with Budd-Chiari syndrome have been documented with elevated serum Epo levels. For these patients, identification of the Janus kinase 2 (JAK2) V617F point mutation along with the transient nature of the Epo elevation provides certainty of PV diagnosis, as illustrated by the proband. In this case report, the patient's positive response to cytoreductive therapy (hydroxyurea 500 mg daily) and phlebotomy (750 mL over three phlebotomies) further supports validity of PV diagnosis with elevated Epo. The patient remains on rivaroxaban (Xarelto) for treatment of her portal vein thrombosis.
真性红细胞增多症（PV）是一种以红细胞增多为特征的骨髓干细胞克隆性疾病。PV的诊断需要排除红细胞增多症的继发原因。一直以来，人们认为促红细胞生成素（Epo）水平升高强烈提示继发性红细胞增多症，并排除PV诊断，以至于血清Epo水平降低目前被列为WHO PV分类方案中的一个次要标准。然而，已有文献记载，合并布加综合征的PV患者血清Epo水平升高。对于这些患者，如先证者所示，Janus激酶2（JAK2）V617F点突变的鉴定以及Epo升高的短暂性为PV诊断提供了确定性。在本病例报告中，患者对细胞减灭疗法（每日500毫克羟基脲）和放血疗法（三次放血共750毫升）的阳性反应进一步支持了Epo升高时PV诊断的有效性。该患者继续服用利伐沙班（拜瑞妥）治疗门静脉血栓形成。
