What does a high white blood cell count usually indicate in CML?

A high white blood cell count in chronic myeloid leukemia (CML) is primarily attributed to the increased production of granulocyte precursors. CML is characterized by an overproduction of myeloid cells, particularly granulocytes, due to the proliferation of cells in the bone marrow. This overproduction leads to elevated levels of white blood cells in the bloodstream, which is a hallmark feature of the disease.

In CML, the abnormal proliferation of cells is typically caused by the Philadelphia chromosome, which results from a translocation between chromosomes 9 and 22. This genetic alteration leads to the fusion of the BCR and ABL genes, producing a tyrosine kinase that drives the proliferation of myeloid progenitor cells. As a result, patients often present with significantly elevated white blood cell counts, primarily consisting of mature and immature granulocytes.

The other options do not accurately reflect the standard implications of a high white blood cell count in the context of CML. Bone marrow suppression, for example, would typically lead to a low white blood cell count rather than a high one. Progression toward acute leukemia would involve different pathological changes and may present differently than the elevated counts seen in CML. While a response to infection can also lead to