Immunoglobulin A (IgA), plasma or serum

Alternate test name

IgA

Lab area

Clinical Biochemistry - General

Method and equipment

Equipment : Roche Cobas Pro c503

Method: Immunoturbidimetric assay
Anti‑IgA antibodies react with antigen in the sample to form an antigen/antibody complex. Following agglutination, this is measured turbidimetrically. Addition of PEG allows the reaction to progress rapidly to the end point, increases sensitivity, and reduces the risk of samples containing excess antigen producing false negative results

Expected turn-around time

STAT/ Urgent: 4 Hours Routine: 24 Hours

Shipping information

Background and clinical significance

Immunoglobulin A (IgA) measurements performed with this assay in human serum and plasma are used as an aid in diagnosis of clinical conditions associated with increased IgA levels, such as infections and inflammatory diseases, and with decreased IgA levels, such as IgA deficiencies. Immunoglobulins (Ig) or antibodies are glycoproteins produced by plasma cells to protect the human body against invading organisms and agents.

Increases of polyclonal immunoglobulins (including IgA) are the normal response to infections. IgA is increased in skin, gut, respiratory, and renal infections.
IgA increases may additionally be associated with chronic inflammatory conditions, including cirrhosis, rheumatoid arthritis, systemic lupus erythematosus and Wiscott‑Aldrich syndrome. Monoclonal IgA increases in diseases where neoplastic proliferation of secretory B cells is present, such as multiple myeloma.

Decreased levels of IgA can be due to reduced synthesis, increased loss, hypercatabolism or a combination of causes. IgA deficiencies occur in congenital and acquired immunodeficiency syndromes, inherited deficiencies, hematologic malignancies.