Initial Evaluation and Laboratory tests
Physical examination reveals bruising on the extremities, and palpation of the spleen shows slight splenomegaly. A complete blood count and blood chemistry tests are performed, the results of which follow:
Results of blood chemistry testing reveal elevated serum levels of uric acid, lactic dehydrogenase, alkaline phosphatase, and bilirubin.
Eleanor’s physician decides to conduct the following tests: bone marrow biopsy to assess the bone marrow histology for fibrosis, appearance of megakaryocytes, and proliferation of myeloid cell lineages; blood test and smear to check for abnormal cell appearance; and genetic testing for BCR-ABL to rule out chronic myelogenous leukemia, and for JAK2V617F and MPL mutations to facilitate a more accurate diagnosis of a myeloproliferative neoplasm.
Results of the bone marrow biopsy show megakaryocyte proliferation and atypia with evidence of reticulin fibrosis, and the blood test and smear shows leukoerythroblastosis. Eleanor is JAK2V617F-positive and BCR-ABL‒negative.