Medical Laboratory Scientist (MLS) ASCP Practice Exam

The type of leukemia characterized by immature cells that are sensitive to Sudan black B is Acute Myelomonocytic Leukemia (AML). Sudan black B is a stain that identifies the presence of myeloblasts and granulocytes in a sample, making it particularly useful in diagnosing AML, which involves both myeloid and monocytic lineage cells.

In the context of AML, the presence of immature myeloid cells in peripheral blood and bone marrow is a hallmark, and the sensitivity to this stain indicates the myeloid differentiation. The Sudan black B stain reacts positively in myeloblasts, providing a clear distinction that is vital for the diagnosis of AML.

Other types of leukemia have different cellular characteristics: Acute Lymphoblastic Leukemia (ALL) typically involves lymphoblasts and does not usually yield a positive result with Sudan black B, as it is specific for myeloid cells. Chronic Myeloid Leukemia (CML) involves more mature cells and chronic features rather than the high proportion of immature cells found in acute presentations. Chronic Lymphocytic Leukemia (CLL) primarily involves small, mature lymphocytes and would not respond positively to Sudan black B staining.

Understanding the specificity of Sudan black B helps in identifying