Diagnostic Usefulness of the Janus Kinase 2 Mutation in non BCR/ABL Myeloproliferative Disorders
A 72 years-old woman presented with gangrene of the second and third fingers of her right hand in May 1997. The CBC revealed 12.3 g/dL of hemoglobin, 26,500/µL of WBC and 1,254,000/µL of PLT. The RBCs were micorcytic and hypochromic. Gastrofibroscopy showed a scar of the gastric ulcer. The cellularity and megakaryocyte were increased. Her initial diagnosis was essential thrombocythemia. During the long period of the follow-up (101 months), her hemoglobin level increased to 15.1g/dL, and the PLT count dropped to 300,000/µL in February 2002, and the PLT maintained was around the lower limit of the normal. Only hydroxyurea was prescribed, and its dosage was reduced to 500 mg/day since February 2002. The PLT and WBC showed a decreasing tendency, while the hemoglobin level was increasing upto 16.5g/dL. With a JAK2 mutation, the diagnosis was changed to PV.\nA 69 years-old woman was transferred to our hospital from a dental clinic in April 2001 due to an abnormal CBC. Her initial hemoglobin level was 16.4 g/dL, WBC 23,890/µL and PLT 1,116,000/µL. The patient had no symptoms or signs of bleeding. The BM aspiration and biopsy results showed an increased cellularity, megakaryocytes and an increased M:E ratio. The serum erythropoietin was below 1.7U/L. The CBC pattern was similar to that of the above mentioned 72 year old patient; the hemoglobin level was in excess of 16.5 g/dL twice over the period of 58 months. With a JAK2 result, her diagnosis was changed to PV.