Immunoglobulin Subclass IgG4, Serum
Reporting Name
Immunoglobulin Subclass IgG4, SSCH Clinical System Name: Miscellaneous Lab Test
Useful For
Supporting the diagnosis of IgG4-related disease
Performing Laboratory

Specimen Type
SerumOrdering Guidance
This test only quantitates the IgG4 protein. If quantitation of all IgG subclass types is wanted, order IGGS / IgG Subclasses, Serum.
Specimen Required
Patient Preparation: Fasting preferred but not required
Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Specimen Volume: 1 mL
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Ambient | 14 days | ||
Frozen | 14 days |
Reference Values
0-<5 months: ≤19.8 mg/dL
5-<9 months: ≤20.8 mg/dL
9-<15 months: ≤22.0 mg/dL
15-<24 months: ≤23.0 mg/dL
2-<4 years: 0.4-49.1 mg/dL
4-<7 years: 0.8-81.9 mg/dL
7-<10 years: 1.0-108.7 mg/dL
10-<13 years: 1.0-121.9 mg/dL
13-<16 years: 0.7-121.7 mg/dL
16-<18 years: 0.3-111.0 mg/dL
≥18 years: 2.4-121.0 mg/dL
Day(s) Performed
Monday through Friday
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
82787
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
IGGS4 | Immunoglobulin Subclass IgG4, S | 2469-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
IGGS4 | Immunoglobulin Subclass IgG4, S | 2469-5 |
Method Description
In this Siemens Nephelometer II method, the light scattered onto the antigen-antibody complexes is measured. The intensity of the measured scattered light is proportional to the amount of antigen-antibody complexes in the sample under certain conditions. If the antibody volume is kept constant, the signal behaves proportionally to the antigen volume.
A reference curve is generated by a standard with a known antigen content on which the scattered light signals of the samples can be evaluated and calculated as an antigen concentration. Antigen-antibody complexes are formed when a sample containing antigen and the corresponding antiserum are put into a cuvette. A light beam is generated with an LED, which is transmitted through the cuvette. The light is scattered onto the immuno-complexes that are present. Antigen and antibody are mixed in the initial measurement, but no complex is formed yet. An antigen-antibody complex is formed in the final measurement.
The result is calculated by subtracting value of the final measurement from the initial measurement. The distribution of intensity of the scattered light depends on the ratio of the particle size of the antigen-antibody complexes to the radiated wavelength.(Unpublished Mayo method; Instruction manual: Siemens Nephelometer II, Version 3, Siemens, Inc., Newark, DE, 2008)
Report Available
1 to 2 daysReject Due To
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |
Method Name
Nephelometry