Serum or Plasma Substance Concentration for Neutrophil Count (Absolute Neutrophil Count, ANC-related marker)

What This Test Measures

This test detects a specific substance in your serum or plasma that correlates with the activity or presence of neutrophils. Neutrophils are a key part of your immune system, helping your body fight off bacteria and infections. The substance measured may be released during inflammation or infection, providing insight into your body’s response to these conditions.

Why It Might Be Ordered

Your healthcare provider may order this test if you have symptoms of infection, such as fever, redness, or swelling, or if you’re at higher risk for infections due to conditions like chemotherapy, diabetes, or immune disorders. It can also be used to monitor treatment progress or check for signs of infection in people with weakened immune systems.

Sample Collection and Preparation

A blood sample is drawn from a vein, usually in your arm. The blood is then processed to separate the serum or plasma from the cells. This test requires a fresh sample, as the substance being measured can change over time.

What to Expect Before the Test

There are no special preparations needed for this test. You can eat, drink, or take medications as usual. If you’re on blood-thinning medications, let your provider know before the test to avoid unnecessary bleeding.