IgA
IgA (immunoglobulin A) is an antibody that plays a crucial role in mucosal immunity, protecting the surfaces of the mouth, airways, digestive tract, and urinary tract from infections.
Category: Inflammation & Immune
Also known as: iga, immunoglobulin a, serum iga, Immune globulin A
Reference range: 70–400 mg/dL (Source: ABIM)
Standard unit: mg/dL
High values may indicate
High IgA levels may indicate IgA myeloma (multiple myeloma), chronic infections, liver cirrhosis, autoimmune diseases, or IgA nephropathy.
Low values may indicate
Low IgA levels may indicate selective IgA deficiency (the most common immunodeficiency), common variable immunodeficiency, or conditions causing protein loss such as nephrotic syndrome.
Frequently asked questions
- What is a normal IgA level?
- A typical reference range for IgA is 70–400 mg/dL (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is IgA measured in?
- IgA is most commonly reported in mg/dL. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do IgA reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track IgA over time?
- Yes. Upload results from any lab and BloodId charts your IgA over time against its reference range, so you can see whether the trend is rising, falling, or stable.