S1 E32 Understanding the Complete Blood Count (CBC) with Differential

Source: StatPearls via the National Center for Biotechnology Information (NCBI) Bookshelf

This comprehensive clinical reference explains the components of the Complete Blood Count (CBC) with differential, breaking down its critical role in patient assessment. It outlines:

• Key Components:

  • Red Blood Cell (RBC) Indices: Includes RBC count, hemoglobin, hematocrit, MCV, MCH, and MCHC.

  • White Blood Cell (WBC) Differential: Evaluates the relative percentages of neutrophils, lymphocytes, monocytes, eosinophils, and basophils.

  • Platelets (PLT): Count and morphology, including mean platelet volume (MPV).

• Normal Ranges: Standard reference intervals for each parameter, with reminders that values can vary based on the local laboratory.

• Clinical Interpretation:

  • Elevations: Potential causes such as infection, inflammation, malignancy, or chronic disease.

  • Decreases: Can suggest bone marrow suppression, autoimmune disease, nutritional deficiencies, or bleeding.

  • Spurious Results: Highlights common pitfalls in automated analysis—e.g., platelet clumping or cold agglutinins—requiring manual smear review.

• Clinical Integration: Stresses the need to interpret CBC values in the context of the whole patient, including symptoms, history, and other diagnostics.