A Study of 8 Patients with Polycythaemia Vera: The Impact of JAK2 (V617F) Mutation on Diagnosis

Background: The discovery of the Janus Kinase 2 (JAK2) gene mutation provides a new molecular approach for the diagnosis of polycythaemia vera (PV). We studied retrospectively patients with a diagnosis of PV at initial presentation to the hospital. They were followed up for an initial period of 2 months. Objective: The objectives were to access the clinicopathological characteristics, impact of identification of JAK2 mutation on diagnosis and treatment strategies. Result: Of the 6 patients with complete medical records, 3 were males (50%). The mean haematocrit values were 59.7%, males had a value of 60.3% while females a values of 59.0%. The total WBC count was 8.8 x 109/L while the platelet count was 463.5 x 109/L. None of the patients’ had splenomegaly, all had pruritus. During follow up the mean haematocrit values were 52.3%, males had a value of 55.8% while females a values of 48.7%. The total WBC count was 11.1 x 109/L while the platelet count was 652.1 x 109/L. There was a reduction in the haematocrit value but the white blood cell and platelet counts remained high. Of the 5 patients who had molecular analysis done, 4(80%) had the JAK2 mutation while in 1 (20%) the mutation was not detected. The results of the molecular analysis done in a regional laboratory were received after an average of 21 days. The patients were treated with phlebotomy and hydroxyurea. One patient with increasing thrombocytosis had clopidogrel initiated. 3 patients were lost in the follow-up period once there was clinical improvement, at 6 months and 1 year only 1 patient was left in follow-up. Conclusion: The lag time for obtaining results of molecular analysis was long, which made diagnosis and management on clinicalbasis. This highlights the need for the upgrading of more laboratories to acquire molecular technology for improved patients care and diagnostic accuracy