Reference range, target level, or decision threshold
0.7-5.0 g/L!
Interpretation of results
↑ Polyclonal: chronic inflammation, parasitic diseases, cirrhosis, AIDS, autoimmune diseases, sarcoidosis, malignancies; monoclonal: IgA myeloma, other monoclonal gammopathies (including monoclonal gammopathy of undetermined significance [MGUS]), lymphomas
↓ Primary: X-linked agammaglobulinemia (Bruton syndrome), common variable immunodeficiency, hyper IgM syndrome, IgA deficiency, IgG subclass deficiency, severe combined immunodeficiency, ataxia-telangiectasia; secondary: lymphoid neoplasms (myeloma, chronic lymphocytic leukemia), histiocytosis, malnutrition, protein-losing enteropathies, nephrotic syndrome, burns, chemotherapy and radiotherapy, glucocorticoid therapy, posttransplant immunosuppression, splenectomy, thymoma, viral infections (Epstein-Barr virus [EBV] infection, rubella, measles)