Karyotype analysis, leukemic blood
24, 48 and/or 72 hour culture / G-banding
7.0 mL (min. 5.0 mL) blood (WBC >10,000) in sodium heparin
Ship with a cool pack (refrigerated).
Call before sending specimen on Friday
Ship Saturday for Monday delivery, and protect specimen from extreme temperature
Clotted specimen; Specimen exposed to extreme temperature; Anticoagulant toxic to cells; Insufficient number of cells
Chromosome count and morphology consistent with normal karyotype
In hematological malignant diseases, recognized recurring chromosomal abnormalities often correlate with particular subtypes of leukemia that have characteristic morphological and clinical features, such as response to therapy. The study of chromosomal abnormalities serves two functions. The first is to assist in diagnosis, thereby providing prognostic information and allowing the selection of therapy; and the second is to identify the sites of consistent rearrangements, providing the precise localization required for the isolation and cloning of DNA from these regions.
Peripheral blood can be used to study the cytogenetics of malignant conditions only if dividing leukemia cells, as in the leukemic stage of lymphoma or in blast crisis leukemia, are present. Blood samples are preferred only in a limited number of leukemias (such as CML and CLL) and lymphomas, respectively.