Description
Why It’s Done
The test is ordered to:
• Evaluate immune system function, particularly B cell activity.
• Diagnose or monitor immunodeficiencies, such as:
o Common Variable Immunodeficiency (CVID)
o X-linked agammaglobulinemia (XLA)
• Monitor immune recovery after chemotherapy, bone marrow, or stem cell transplantation.
• Assess autoimmune conditions, lymphomas, or leukemias affecting B cells.
• Guide treatment decisions in patients receiving B-cell-depleting therapies (e.g., rituximab).
Preparation
• Fasting: Not necessary.
• Medications: Inform your doctor of any medications, especially immunosuppressants or biologics.
• Timing: Can be done at any time of day.
• Hydration: Drink plenty of water before the blood draw.
