The Sudan Black B (SBB) stain aids in differentiation of the immature cells of acute leukemias, especially acute myeloblastic leukemia. The SBB stains a variety of fats and lipids that are present in myeloid leukemias but are not present in the lymphoid leukemias.
Obtain bone marrow aspirate.
Prepare slide, stain with SBB, and scan microscopically. Use normal smear control.
Positive staining of primitive (blast) cells indicates myelogenous origin of cells. SBB is positive in acute myelocytic leukemia (AML).
SBB is negative in acute lymphocytic leukemia (ALL), monocytic leukemia, plasma cell leukemia, and megakaryocytic leukemia.
SBB is weak to negative in acute monocytic leukemia.
Pretest Patient Care
Explain test purposes and procedures. If bone aspiration is performed, refer to “Bone marrow” entry for information regarding pre and posttest care.
Follow guidelines in Chapter 1 for safe, effective, informed pretest care.
Posttest Patient Care
Review test results; report and record findings. Modify the nursing care plan as needed.
Counsel the patient regarding abnormal findings; explain the need for possible follow-up testing and treatment. Monitor for leukemia, amyloid disease, anemia, and infection.
Follow guidelines in Chapter 1 for safe, effective, informed posttest care.
There are cases of acute leukemia in which the cytochemical stains are not useful and fail to reveal the differentiating features of any specific cell line.
Positive Reactions
Granulocytic cells (neutrophils and eosinophils)
Myeloblasts
Promyelocytes
Neutrophilic myelocytes
Metamyelocytes, bands, and segmented neutrophils
Eosinophils at all stages
Monocytes and precursors
Variable Reactions
Basophils
Negative Reactions (Sudanophobia)
Lymphocytes and lymphocytic precursors
Megakaryocytes and thrombocytes (platelets)
Erythrocytes
Erythroblasts may display a few granules that represent mitochondrial phospholipid components.