Jalowiec Katarzyna Aleksandra, Vrotniakaite-Bajerciene Kristina, Jalowiec Jakub, Frey Noel, Capraru Annina, Wojtovicova Tatiana, Joncourt Raphael, Angelillo-Scherrer Anne, Tichelli Andre, Porret Naomi Azur, Rovó Alicia
Department of Haematology and Central Haematology Laboratory, University Hospital/Inselspital Bern, University of Bern, 3010 Bern, Switzerland.
Independent Researcher, 02-776 Warsaw, Poland.
J Clin Med. 2022 Jun 13;11(12):3393. doi: 10.3390/jcm11123393.
(1) Background: Polycythaemia is defined by an increase in haemoglobin (Hb) concentration, haematocrit (Hct) or red blood cell (RBC) count above the reference range adjusted to age, sex and living altitude. JAK2 unmutated polycythaemia is frequent but under-investigated in original publications. In this retrospective cohort study, we investigated the clinical and laboratory data, underlying causes, management and outcomes of JAK2 unmutated polycythaemia patients. (2) Methods: The hospital database was searched to identify JAK2 unmutated patients fulfilling WHO 2016 Hb/Hct criteria for PV (Hb >16.5 g/dL in men and >16 g/dL in women, or Hct > 49% in men and >48% in women, or RBC mass > 25% above mean normal predicted value) between 2008 and 2019. Clinical and laboratory data were collected and analysed. (3) Results: From 727,731 screened patients, 294 (0.04%) were included, the median follow-up time was 47 months. Epo and P50 showed no clear pattern in differentiating causes of polycythaemia. In 30%, the cause remained idiopathic, despite extensive work-up. Sleep apnoea was the primary cause, also in patients under 30. Around 20% had received treatment at any time, half of whom had ongoing treatment at the end of follow-up. During follow-up, 17.2% developed a thromboembolic event, of which 8.5% were venous and 8.8% arterial. The mortality was around 3%. (4) Conclusions: Testing for Epo and P50 did not significantly facilitate identification of underlying causes. The frequency of sleep apnoea stresses the need to investigate this condition. Idiopathic forms are common. A diagnostic flowchart based on our data is proposed here. NGS testing should be considered in young patients with persisting polycythaemia, irrespective of Epo and P50 levels.
（1）背景：真性红细胞增多症的定义是血红蛋白（Hb）浓度、血细胞比容（Hct）或红细胞（RBC）计数高于根据年龄、性别和居住海拔调整后的参考范围。JAK2未突变的真性红细胞增多症很常见，但在原始文献中研究不足。在这项回顾性队列研究中，我们调查了JAK2未突变真性红细胞增多症患者的临床和实验室数据、潜在病因、治疗及预后情况。（2）方法：检索医院数据库，以确定2008年至2019年间符合世界卫生组织2016年真性红细胞增多症（PV）Hb/Hct标准（男性Hb>16.5 g/dL，女性Hb>16 g/dL，或男性Hct>49%，女性Hct>48%，或红细胞量高于正常预测平均值的25%）的JAK2未突变患者。收集并分析临床和实验室数据。（3）结果：在727731名筛查患者中，纳入了294名（0.04%），中位随访时间为47个月。促红细胞生成素（Epo）和P50在区分真性红细胞增多症病因方面无明显规律。尽管进行了广泛检查，但30%的病因仍为特发性。睡眠呼吸暂停是主要病因，30岁以下患者中也是如此。约20%的患者曾在任何时间接受过治疗，其中一半在随访结束时仍在接受治疗。随访期间，17.2%的患者发生了血栓栓塞事件，其中8.5%为静脉血栓，8.8%为动脉血栓。死亡率约为3%。（4）结论：检测Epo和P50并不能显著有助于确定潜在病因。睡眠呼吸暂停的发生率强调了对此疾病进行调查的必要性。特发性类型很常见。本文基于我们的数据提出了一个诊断流程图。对于持续性真性红细胞增多症的年轻患者，无论Epo和P50水平如何，都应考虑进行二代测序（NGS）检测。
