An Introduction to the Complete Blood Count for Clinical Chemists: White Blood Cells

Abstract Background The most frequently ordered laboratory test worldwide is the complete blood count (CBC). As clinical chemists are increasingly assigned to assist or direct laboratories outside of the traditional clinical chemistry sections, such as the automated hematology section, expertise must be established. This review article is a dedication to that ongoing effort. Content In this primer, the white blood cell (WBC) test components of the CBC are introduced, followed by a discussion of the laboratory evaluation of leukopenia and leukocytosis. Summary The laboratorian's approach to consult cases should be guided by the patient's clinical history and presentation while being able to provide key laboratory-based insights to assist in resolving result discrepancies that may otherwise go unnoticed.