NOTE: The effect of nucleated erythrocytes and blood megakaryocytes on the apparent WBC
count varies with the system used for analysis. Each laboratory should evaluate its system(s) and
develop appropriate detection and correction procedures. This is important to prevent reporting a
falsely high WBC concentration. With some automated CBC instruments, nucleated erythrocytes
or megakaryocytes may present themselves histographically or cytographically, and this can
serve as an indicator for careful stained blood film inspection. The laboratory must establish if
its particular instrument(s) includes some or all nucleated non-leukocytes in its apparent WBC
"count".
Evidence of Compliance:
✓ Records showing actions taken to verify CBC concentration prior to reporting