Coexistence of thalassemia syndrome with myeloproliferative neoplasias -- case series.

Introduction: Thalassemia and myeloproliferative neoplasias (MPNs) are two separate disease entities. Thal. is an inhereted congenital hemolytic anemia caused by abnormal globin gene synthesis. MPNs are acquired clonal hematopoietic stem cell diseases characterized by the proliferation of different hematopoietic stem cells. The coexistence of thal. and MPNS are rarely reported. Methods: We performed a single-center retrospective analysis of all cases known to have thal. including patients developing persistent high levels of hemoglobin or platelet. The diagnosis of MPN was confirmed by genetic testing from peripheral blood, bone marrow biopsy and blood film analysis. Results: In this case series, we report six cases with coexistence of alpha(α), beta(β) and delta-beta (δβ) thal. with different types of MPNs including essential thrombocytosis ( ET ) and polycythemia vera. Majority of these patients had positive Janus kinase (jak 2) mutation, except for one patient with diagnosis of ET who had calreticulin (CALR) gene mutation. Most of the patient in our case series are younger than average age for the diagnosis of MPNs.