White Blood Cell (WBC) Peripheral Blood Count (Automated)

What Does This Test Measure?

The test counts five main types of white blood cells: neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Each type plays a role in immune defense, such as fighting bacteria, viruses, or responding to allergies. The total count and individual counts can provide clues about your health status.

Why Might You Need This Test?

Doctors may order this test to diagnose or monitor conditions like infections (e.g., pneumonia, urinary tract infections), autoimmune diseases (e.g., lupus, rheumatoid arthritis), blood disorders (e.g., leukemia, anemia), or to check for signs of inflammation.

How Is This Test Done?

A small blood sample is drawn from a vein, usually in your arm. The blood is then analyzed automatically in a lab to count white blood cells and their subtypes. No special preparation is needed, but fasting may not be required unless instructed by your doctor.

What Are Common Results?

Results are typically reported as a total WBC count (in thousands of cells per microliter) and individual counts for each cell type. While reference ranges vary by lab, abnormal counts may suggest infections, immune disorders, or other health concerns.