Laboratory Medicine
Test Directory / Immunoglobulins
Immunoglobulins
Brown clotted serum, gel barrier or lithium heparin
| Test | Immunoglobulins |
|---|---|
| Common Abbreviations | IgA / IgG / IgM |
| Profile | NA |
| Tube type | Brown clotted serum, gel barrier or lithium heparin |
| Clinical Indication | Changes in immunoglobulin concentrations can be classified as hypogammaglobulinaemias (e.g. in autoimmune disorders such as SCID), polyclonal gammopathies (e.g. autoimmune disease, chronic liver disease or infection) and monoclonal gammopathies (e.g. in multiple myeloma or Waldenstrom's macroglobulinaemia). |
| Specimen Type | Blood |
| Sample type | Serum or plasma |
| Minimum Volume | 0.5mL If requesting more than 10 tests please send an additional brown clotted serum sample. |
| Special Precautions | No special requirements |
| Stability | 2 months at15-25°C and 4 months at 2-8°C |
| Turnaround Time | Inpatient: 6 hours Outpatient/ GP: 24 hours |
| Laboratory | York and Scarborough |
| Reference Interval | IgM: 6 years to 45 years: 0.5-1.9g/L >45 years = 0.5-2.0g/L IgG: Adults: 6-16g/L IgA: <45 years = 0.8-2.8g/L >45 years = 0.8-4.0g/L |
| Limitations | The assay has been optimised to reduce the risk of prozone occurrence in the presence of abnormally high immunoglobulin concentrations. Patients with suspected paraproteinaemia should also be tested by electrophoresis. Samples with very high IgM concentrations (>100g/l polyclonal) can generate falsely low results due to excess antigen in the sample. Samples with extremely abnormal optical characteristics, especially turbidity, may produce atypical results. High concentrations of protein (IgG >70 g/L, IgA >13 g/L, IgM >10 g/L) may cause interference in the vitamin D assay leading to falsely high results. Interpret in clinical context and contact duty biochemist to discuss if concerned. |
| Notes |
