Absolute Neutrophil Count (ANC), Whole Blood

What it is:
The Absolute Neutrophil Count (ANC) measures the number of neutrophils, a type of white blood cell that serves as the body’s first line of defense against bacterial and fungal infections, in the blood.

• ANC is usually calculated from a Complete Blood Count (CBC) with differential.

Uses of the Test

• Evaluate immune system health

• Monitor patients undergoing chemotherapy, radiation, or immunosuppressive therapy

• Diagnose bone marrow disorders, infections, or autoimmune diseases

• Assess infection risk in people with low white blood cell counts

Symptoms That May Lead to the Test

Doctors may order this test if a patient presents with:

• Frequent or severe infections

• Fever without an obvious cause

• Fatigue, weakness, or unexplained illness

• Signs of bone marrow suppression (e.g., after chemotherapy)

• Autoimmune or hematological disorders

Causes of Abnormal ANC

• High ANC (Neutrophilia):

  • Acute bacterial infections

  • Inflammation (e.g., rheumatoid arthritis, inflammatory bowel disease)

  • Stress, trauma, or recent surgery

  • Certain leukemias or bone marrow disorders

  • Corticosteroid use

• Low ANC (Neutropenia):

  • Chemotherapy or radiation therapy

  • Bone marrow failure (e.g., aplastic anemia, leukemia)

  • Autoimmune diseases (e.g., lupus, rheumatoid arthritis)

  • Viral infections (HIV, hepatitis, influenza)

  • Certain medications (antibiotics, anti-thyroid drugs, anticonvulsants)

  • Severe vitamin B12 or folate deficiency

Side Effects / Risks of the Test

• Mild pain, bruising, or bleeding at the puncture site

• Rarely dizziness or infection

Reference Ranges (Approximate; may vary by lab)

• Adults: 1,500 – 8,000 cells/µL (1.5 – 8.0 × 10⁹/L)

• Children: Similar range, slightly higher in newborns

Severity of Neutropenia (low ANC):

• Mild: 1,000 – 1,500/µL

• Moderate: 500 – 1,000/µL

• Severe: < 500/µL (high risk of life-threatening infection)