Chronic neutrophilic leukemia with acute myeloblastic transformation

We report a rare case of chronic neutrophilic leukemia (CNL) which terminat ed in acute myeloblastic transformation 3 years after the onset of the dise ase. The increased leukocytes were mainly neutrophils at various maturation al stages until 1 month before transformation without dysplastic hematopoie tic cells or other myeloproliferative disorders. Repeated analyses for the Philadelphia chromosome (Ph1), rearrangement of the BCR gene or chimeric BC R/ABL mRNA, major, minor and mu, were negative. Genomic analysis of granulo cyte colony-stimulating factor (G-CSF) receptor did not reveal any abnormal ity. The clinical manifestations were characterized by hyperleukocyte syndr ome with respiratory distress and ischemic legs with gangrene.