Immunoglobulin G (IgG), plasma or serum

Alternate test name

IgG

Lab area

Clinical Biochemistry - General

Method and equipment

Equipment : Roche Cobas Pro c503

Method: Immunoturbidimetric assay.
Anti‑IgG 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 G (IgG) measurements performed with this assay in human serum and plasma are used as an aid in diagnosis of clinical conditions associated with increased IgG levels, such as infections and inflammatory diseases, and with decreased IgG levels, such as IgG deficiencies.

Increases of polyclonal immunoglobulins (including IgG) in serum/plasma are the normal response to infections. IgG increases may additionally be
associated with chronic inflammatory conditions, including systemic lupus erythematosus, cystic fibrosis, cirrhosis and autoimmune hepatitis. Monoclonal IgG increases in diseases where neoplastic proliferation of secretory B cells is present, such as multiple myeloma.

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