Chronic myeloproliferative diseases (MPDs) are heterogenous group of haematological malignant disorders. It is now a well recognized fact that the JAK2 (V617F) mutation occurs in majority of the patients with polycythaemia vera (PV) and half of those with myelofibrosis and essential thrombocythaemia. The presence of JAK2 (V617F) mutation is considered an important criterion for the exclusion of secondary-reactive from clonal disorders. In the present uni-institutional study, we analyzed the JAK2 (V617F) mutation status in the ethnic Malay and Chinese patients who were diagnosed as MPDs.
Chronic Myeloid Leukemia (CML) is a clonal disorder thought to originate in a single abnormal haematopoietic stem cell. This myeloproliferative fatal stem cell disorder comprises
approximately 14% of all leukemias. In most cases, CML runs a triphasic course, which includes an initial chronic phase that transforms eventually into a blastic phase resembling acute leukemia. In 60%- 80% of patients, an intermediate or accelerated phase precedes the terminal blastic phase. Accelerated phase and blastic phase sometimes are lumped together and considered to be
advanced phase CML. The entire continuum from chronic phase to blastic phase lasts a median of 3 to 5 years . This time period can be broken down in to the chronic phase which if untreated,
lasts for 2 to 5 years and finally the fatal blastic phase, which lasts from 3 to 6 months. A patient can present in any of these 3 stages.
Transient abnormal myelopoeisis (TAM) is a haematological phenomenon commonly seen in newborns with Down syndrome. Although the majority show spontaneous resolution, this condition should not be dismissed too readily as there have been associated fatalities. Furthermore, even for those who do show spontaneous resolution, a significant percentage will develop acute megakaryoblastic leukaemia within the next few years of life. We report a series of four patients with TAM who presented with hepatosplenomegaly and leucocytosis detected on preliminary investigations.
Introduction: It is mandatory that every blood donor must have their haemoglobin (Hb) values measured before blood donation. High Hb may indicate an underlying hidden pathological condition. The aim of this study is to investigate the occurrence of the JAK2 V617F gene mutation in blood donors with erythrocytosis. Methods: A cross-sectional study was conducted over a nine-month period involving blood donors with high pre-donation Hb. A total of 45 blood donors with total white cell (TWC) > 12.0x 109/l, platelet > 450x109/ l and Hb > 18g/dL were subjected to JAK2 V617F gene mutation analysis. Samples were collected and analysed for haematological tests and detection of JAK2 V617F mutation. Results: From a total of 2238 blood donors, 175 blood donors had high haemoglobin value. Samples from forty-five of these donors were then analysed for JAK2 V617F using allele-specific polymerase chain reaction (PCR). The prevalence of blood donors with erythrocytosis was 7.8%. All samples were negative for the JAK2 V617F mutation. Conclusions: Erythrocytosis can be relative or absolute and the different causes can be distinguished on the basis of clinical signs and symptoms. An absence of the JAK2 V617F mutation cannot by itself excludes the diagnosis of polycyhaemia vera (PV) since erythrocytosis is the single clinical feature that sets PV apart from other types of myeloproliferative neoplasm (MPN). Further study is required for the detection of other gene mutations that activates the JAK-STAT signalling pathway that could be identified in JAK2 V617F-negative MPN patients.
Extramedullary hematopoiesis (EH) is a rare but well-known compensatory mechanism of red blood cell production when the normal site of red bone marrow is unable to produce sufficient number of red blood cells. When the body demands for erythrocyte cells is high this lead to EH. This occurs mainly outside the bone marrow, usually paraspinally and sites which are normally observed in the fetus as in the liver, spleen, lymph nodes and less frequently at other sites such as adrenal, thymus, kidneys, pleura, breast, skin, gastrointestinal tract, dura mater and brain.This is more frequent in thalassaemia major (incidence up to 15% of cases), in myelofibrosis, myeloproliferative diseases (polycythemia rubra vera, chronic myeloid leukemia,), hemolytic anemias such as hereditary spherocytosis, pyruvate-kinase deficiency, medullary tuberculosis and in Paget’s disease of the bone. In some cases the cause of the EH are not identified [3]. We describe a case of EH in the presacral space that mimicked an ovarian mass on ultrasound in a patient with beta-thalassaemia intermedia.