IgA stands for immunoglobulin A, one of the classes of immunoglobulins (also called antibodies) that are in the blood. IgA is important in protecting 'mucosal surfaces' – the linings of the tracts of the body, e.g. the lungs, and is secreted in saliva and tears. It protects against infections of the mucous membranes lining the mouth, airways, and digestive tract.
Causes and Development
Low levels of IgA
occur in some types of leukemia
damage (nephrotic syndrome), a problem with the intestines (enteropathy), and a rare inherited disease that affects muscle coordination (ataxia-telangiectasia). Some people are born with low or absent levels of IgA antibodies
, which increases their chances of developing an autoimmune disease
Diagnosis and Tests
The 'low', 'normal' and 'high' ranges vary with age, and are also lab-specific. However, a reasonable normal range is 80-350mg/dl.