Immunoglobulin G (IgG) Subclass 2 Concentration in Serum

What Does This Test Measure?

IgG2 is one of five subclasses of Immunoglobulin G (IgG), the most common type of antibody in your blood. IgG2 antibodies are particularly important for defending against certain types of bacteria, such as those causing respiratory infections. Your body produces IgG2 in response to repeated exposure to certain pathogens. This test helps assess your immune system’s ability to fight specific infections and may be used in conditions where IgG2 levels are known to be important, such as certain autoimmune diseases or immune deficiencies.

Why Might You Need This Test?

Doctors may order an IgG2 test to evaluate immune function, especially in cases where IgG2 levels are suspected to be low or abnormal. This can occur in conditions like common variable immunodeficiency (CVID), certain autoimmune diseases, or after treatments that affect antibody production.

Preparation for the Test

No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw a blood sample. If you are on blood thinners or have a history of bleeding issues, let your healthcare provider know before the test.

What to Expect After the Test

After the blood is drawn, you may feel a slight pinch or bruising at the site. Most people recover quickly without complications. If you experience excessive bleeding, pain, or signs of infection (like redness or swelling), contact your healthcare provider.