A 77 year-old woman was admitted with progressive general malaise, weight loss, fever, productive cough and nasal bleeding. Physical examination revealed icterus and moderate hepatosplenomegaly. Hematological study showed pancytopenia with erythroblastosis and conspicuous dysplasia of trilineage blood cells. Bone marrow, aspirated with moderate difficulty, was erythroblastically hypercellular and almost consisted of megaloblastoid immature cells. Disseminited intravascular coagulation developed soon after the admission and she was treated with transfusion, heparin and low dose Ara-C. However, she died of bleeding from gastric ulcer on the 29th hospital day. An Autopsy disclosed moderate bone marrow fibrosis with proliferation of atypical megakaryocytes, erythroblasts and immature cells. Similar cells proliferated also in the liver, spleen, kidneys and para-aortic lymph nodes. In vitro hematopoietic colony formation from bone marrow and peripheral blood was markedly decreased, but some CFU-GEMM and BFU-E-derived colonies developed without exogenous erythropoietin. Erythroid cells in the mixed colonies and erythroid bursts were mostly immature megaloblasts. Cytogenetic analysis was performed on single mixed colonies and pooled erythroid bursts, and a same abnormal karyotype of 47, XX, +C was revealed as in the direct analysis on the peripheral blood cells.
These results show that this patient had a clonal disorder originated from a multipotent stem cell, which coincides with the clinical features of acute mylodysplasia with myelofibrosis, a type of acute myelofibrosis.
