What is Total IgA?
Total IgA measures the concentration of Immunoglobulin A in the blood, an antibody that plays a crucial role in immune defense—particularly in the mucous membranes of the respiratory, gastrointestinal, and urogenital tracts. It is the body’s first line of defense against inhaled, ingested, and sexually transmitted pathogens.
Why is Total IgA important?
IgA provides immune protection by neutralizing viruses and bacteria before they penetrate deeper into the body. It is also involved in maintaining a healthy balance of immune tolerance in the gut. Abnormal IgA levels can signal underlying immune disorders or chronic inflammatory conditions.
Low Total IgA may indicate:
-
Selective IgA deficiency – the most common primary immunodeficiency
-
Increased susceptibility to respiratory or gastrointestinal infections
-
Celiac disease, even when asymptomatic
-
Certain autoimmune or inflammatory conditions
-
Protein-losing conditions, such as nephrotic syndrome
High Total IgA may indicate:
-
Chronic infections, especially those affecting mucosal surfaces
-
Liver disease, such as cirrhosis
-
Autoimmune diseases, like lupus or rheumatoid arthritis
-
Inflammatory bowel diseases, such as ulcerative colitis or Crohn’s disease
-
Monoclonal gammopathies, like IgA myeloma
Who should consider testing Total IgA?
This test is useful for individuals with frequent respiratory or digestive infections, unexplained inflammation, or suspected immune deficiency. It is also commonly included in celiac disease screening panels.
Clinical note:
Since IgA is involved in mucosal immunity, a low level may impair the body’s ability to defend against infections and tolerate harmless antigens, potentially leading to increased inflammation or autoimmunity.
Total IgA
Every lab result you’ve ever had, charted and explained.
Healthmatters is a tracker for your lab results. Upload a report from any lab, any country — every marker charted and explained.
Start with my report →
All our content is backed by peer-reviewed studies, academic research, and trusted medical sources. We’re committed to accuracy and transparency — see our editorial policy for details.