Acute megakaryoblastic leukemia (acute "malignant" myelofibrosis): an unusual cause of osteosclerosis.

Acute megakaryoblastic leukemia or acute "malignant" myelosclerosis is an acute and rapidly progressive myeloproliferative syndrome characterized by minimal or absent splenomegaly, pancytopenia, diffuse marrow fibrosis, and circulating blasts of megakaryocytic origin. The disease must be differentiated from other hematologic malignancies especially myelofibrosis with myeloid metaplasia. The radiographic changes of osteosclerosis in our patient have not been previously reported in the literature.