From March 2016, a trend to increased lactate dehydrogenase (LDH) levels was noticed, and from February 2019, a mild macrocytic anemia developed ( Figure 1). Once-daily acetylsalicylic acid (ASA) and low-dose hydroxyurea (HU) were started with adequate control of platelet count. Bone marrow (BM) evaluation showed normocellularity (40%), increased mature megakaryocytes, slight increase of reticulin fibers (MF-1), and normal karyotype. His medical history was unremarkable, except for moderate arterial hypertension on regular treatment no previous thrombotic events were registered. Case DescriptionĪ 62-year-old Caucasian male was diagnosed with Janus kinase (JAK)2-negative essential thrombocythemia (ET) in May 2007 due to isolated asymptomatic thrombocytosis ( Table 1). In detail, we reviewed data about the coexistence of clinically overt PNH and MPN, the prevalence of PNH clones in MPN patients, and the prevalence of MPN driver mutations in PNH subjects. In addition, we searched for the available evidence in literature about the association of PNH and MPN, collecting data over the last 40 years in MEDLINE via PubMed and the National Library of Medicine. Here, we provide the description of a patient with MPN who was subsequently diagnosed with PNH and required specific treatment for hemolytic anemia. ![]() Moreover, these two conditions share an overlapping clinical presentation, represented by thrombotic events at usual and unusual sites ( 3, 10– 13). The coexistence of PNH and myeloproliferative neoplasms (MPNs) has been reported, but its clinical/prognostic significance and therapeutic management are still poorly known. However, with the development of more sensitive cytofluorimetric techniques ( 5), PNH clones of various sizes are increasingly being detected in various onco-hematologic and autoimmune disorders ( 6– 9). PNH has been described in the context of bone marrow failure (BMF) syndromes, namely, aplastic anemia (AA) and myelodysplastic syndrome (MDS) ( 4). With the advent of complement inhibitors, PNH patients significantly ameliorated their quality of life and survival ( 4). The natural history of PNH was burdened by high morbidity due to chronic anemia and considerably increased mortality, mainly related to fatal thrombotic events ( 3). ![]() The consequent defect of glycosyl phosphatidylinositol (GPI)-anchored proteins on red blood cell (RBC) surface increases the susceptibility of PNH cells to complement-mediated destruction, leading to intravascular hemolytic anemia, which is the main clinical feature of the disease ( 1, 2). Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder caused by the somatic mutations of phosphatidylinositol glycan A ( PIGA). The latter showed only partial effectiveness in controlling hemolytic anemia and, due to the paucity of data, should be taken in consideration after a careful risk/benefit evaluation in this peculiar setting. Thrombotic events were a common clinical presentation (35% of subjects), sometimes refractory to combined treatment with cytoreductive agents, anticoagulants, and complement inhibitors. The prevalence of PNH clones in MPN patients is about 10%, mostly in association with JAK2V617F-positive myelofibrosis. ![]() Moreover, we performed a review of the literature regarding the clinical and pathogenetic significance of the association of PNH and MPN. The patient started eculizumab, obtaining good control of intravascular hemolysis but without amelioration of transfusion-dependent anemia. Here, we describe a 62-year-old man who developed a highly hemolytic PNH more than 10 years after the diagnosis of MPN. ![]() The therapeutic management of this rare combination has not been defined so far. Rarer associations include myeloproliferative neoplasms (MPNs), which are also burdened by increased thrombotic tendency. Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by intravascular hemolytic anemia and thrombosis and is notoriously associated with aplastic anemia and myelodysplastic syndromes.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |