Total Immunoglobulin G (IgG) Profile (Serum/Plasma Mass Concentration)

What Does This Test Measure?

IgG is the most abundant antibody in your blood, playing a critical role in long-term immunity. This test quantifies the total concentration of IgG in your serum or plasma, which can help assess immune function, diagnose conditions like hypogammaglobulinemia, or monitor treatment responses in patients with immune-related disorders.

Why Might You Need This Test?

Your healthcare provider may order this test if you have symptoms of weakened immunity (e.g., frequent infections), a history of recurrent infections, or if you’re receiving treatments that affect your immune system (e.g., chemotherapy, immunosuppressive drugs). It may also be used to evaluate immune-related conditions or monitor immune responses.

How Is the Test Performed?

A blood sample is drawn from a vein in your arm. The blood is then processed to separate serum or plasma, which is sent to a lab for analysis using a specialized immunoassay or nephelometry method to measure IgG concentration.

What Do the Results Mean?

Results are typically reported in grams per deciliter (g/dL) or milligrams per milliliter (mg/mL). While reference ranges vary by lab, lower-than-expected IgG levels may indicate immune deficiencies, while higher-than-expected levels could be associated with certain autoimmune conditions or chronic infections.