Effect of hydroxyurea on extramedullary haematopoiesis in thalassaemia intermedia: case reports and literature review

Abstract

Extramedullary haematopoiesis (EH) is the production of blood cell precursors outside the bone marrow that occurs in various disorders, such as thalassaemia, sickle cell anaemia, hereditary spherocytosis, polycythaemia vera, myelofibrosis and other haematological diseases. In chronic anaemia, it is a physiological response to increased erythropoietin. In some other conditions, such as myeloid metaplasia, polycythaemia vera or chronic myeloid leukaemia, EH is due to a clonal disorder of haematopoiesis that enables progenitor cells to escape from the marrow and lodge in other organs. EH usually involves the liver, spleen and lymph nodes or it can be paravertebral, intrathoracic, pelvic. It is often asymptomatic but can sometimes lead to symptomatic tumour-like masses. Treatment options are still controversial and limited, including hypertransfusion regimen, surgical treatment, radiotherapy and hydroxyurea (HU). We describe intrathoracic and symptomatic pelvic EH masses in a 48-year-old woman and intrathoracic bilateral masses causing respiratory insufficiency with pleural effusion in a 42-year-old male, both affected by thalassaemia intermedia. Both patients showed a clinical improvement with hydroxyurea therapy and occasional blood transfusions.

Spinal cord compression due to extramedullary hematopoiesis in a patient with E-beta-thalassemia managed without radiation or surgery

“…The successful use of hydroxyurea as monotherapy has been reported in the management of EMH masses [8–10]. These patients either had autoimmune hemolytic anemia limiting the use of transfusion [9], hemoglobin level was above 7 g/dL [11], hemoglobin level was at baseline [8], or clinical presentations involving sites other than the spinal cord lessening the urgency of mass shrinkage [12]. Hydroxyurea monotherapy was also the treatment of choice in a patient with cirrhosis when there was a concern for volume overload from transfusion [13], but the response was short lived.…”

Hemoptysis as a presentational finding of intrathoracic paravertebral mass of extramedullary erythropoiesis in a patient with β-thalassemia intermedia

“…Regular erythrocyte transfusion programme is the first line treatment of EME (5). Radiotherapy can be chosen in conditions when rapid response is needed like spinal cord compressions with considering its toxic effects.…”

New Experimental Anemic Model by Using a Nitrogen- Containing Bisphosphonate

“…Extramedullary erythropoiesis occurs in various organs, including the lungs, heart, thymus, and hemal nodes, under abnormal conditions such as acute anemia [31][32][33][34][35][36][37][38].…”