PDF(Pubmed)
Abstract：
Paroxysmal nocturnal hemoglobinuria (PNH) results from the loss of erythrocyte surface proteins, leading to complement activation and its spectrum of effects. We explore this case of a 57-year-old man with post-essential thrombocythemia (ET) myelofibrosis (MF) who developed symptomatic anemia with evidence of hemolysis on lab work. While hemolysis was localized to be intramedullary based on workup, the exact diagnosis was undetermined, leading to a prolonged course of steroid therapy to control anemia. The hemolysis was eventually attributed to PNH diagnosed on flow cytometry and the patient was treated with complement inhibitors with eventual failure of therapy. He ultimately underwent a successful hematopoietic cell transplant (HCT) with post-transplantation flow cytometry showing complete resolution of PNH. While PNH has been identified as a progression of myelodysplastic syndromes, the mechanisms of its rare development in myeloproliferative neoplasms are poorly elucidated. Furthermore, its rarity and often vague symptoms make diagnosis and treatment a challenge. This is the second reported case of a JAK2-negative, CALR-positive post-ET MF and the first reported case to be treated with HCT. This case probes for further insight into the clinical significance between MF and PNH, its impact on management, and further consideration for HCT as curative therapy in such patients who fail complement inhibitor therapy.
摘要：
阵发性睡眠性血红蛋白尿（PNH）是由于红细胞表面蛋白的丢失引起的，导致补体激活及其效应谱。我们探讨了一例57岁的原发性血小板增多症（ET）骨髓纤维化（MF）患者，该患者在实验室工作中出现有溶血证据的有症状性贫血。虽然根据检查，溶血局部为髓内，确切的诊断还不确定,导致长期的类固醇治疗以控制贫血。溶血最终归因于流式细胞术诊断的PNH,并且患者用补体抑制剂治疗,最终治疗失败。他最终成功进行了造血细胞移植（HCT），移植后流式细胞术显示PNH完全消退。虽然PNH已被确定为骨髓增生异常综合征的进展，其在骨髓增殖性肿瘤中罕见发展的机制尚不清楚。此外，它的稀有性和通常模糊的症状使诊断和治疗成为挑战。这是报告的第二例JAK2阴性病例，CALR阳性ET后MF和第一例报告的病例接受HCT治疗。此病例旨在进一步了解MF和PNH之间的临床意义，它对管理的影响，并进一步考虑将HCT作为补体抑制剂治疗失败的此类患者的治愈性治疗。
