Test Code SFIGS LAB9766 IgG, Serum
Additional Codes
LAB9766
SFIGS
Specimen Required
Only orderable as part of a profile. For more information see SFIG / Cerebrospinal Fluid IgG Index Profile, Serum and Spinal Fluid.
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Within 2 hours of collection, centrifuge and aliquot serum into a plastic vial.
DRAW 2 TUBES
Secondary ID
610784Useful For
Aiding in the diagnosis of multiple sclerosis and other central nervous system inflammatory conditions as a part of a profile
Method Name
Only orderable as part of a profile. For more information see SFIG / Cerebrospinal Fluid IgG Index Profile, Serum and Spinal Fluid.
Nephelometry
Specimen Type
SerumDRAW 2 TUBES
Specimen Minimum Volume
0.5 mL
SEND 2.0 mL total serum in 2 plastic vials, each vial containing 1.0 mL Serum
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 14 days |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |
Reference Values
Only orderable as part of a profile. For more information see SFIG / Cerebrospinal Fluid IgG Index Profile, Serum and Spinal Fluid.
0-4 months: 100-334 mg/dL
5-8 months: 164-588 mg/dL
9-14 months: 246-904 mg/dL
15-23 months: 313-1,170 mg/dL
2-3 years: 295-1,156 mg/dL
4-6 years: 386-1,470 mg/dL
7-9 years: 462-1,682 mg/dL
10-12 years: 503-1,719 mg/dL
13-15 years: 509-1,580 mg/dL
16-17 years: 487-1,327 mg/dL
≥18 years: 767-1,590 mg/dL
Interpretation
Cerebrospinal fluid (CSF) IgG synthesis rate indicates the rate of increase in the daily CSF production of IgG in milligrams per day. A result greater than 12 mg/24 h is elevated.
A CSF IgG index greater than 0.70 is elevated and indicative of increased synthesis of IgG.
Method Description
Serum IgG:
The serum IgG is determined by immunonephelometry.(Instruction manual: Siemens BN II Nephelometer Operations. Siemens, Inc.; V 2.3, 2008; Addendum to the Instruction Manual 2.4 07/2019)
Serum albumin:
Serum albumin is measured by colorimetry. The dye, bromocresol green (BCG), is added to serum in an acid buffer. The color intensity of the blue-green albumin-BCG complex is directly proportional to the albumin concentration and is determined photometrically.(Package insert: ALB2. Roche Diagnostics; V 8.0, 06/2024)
Day(s) Performed
Monday through Friday
Report Available
Same day/1 to 2 daysSpecimen Retention Time
2 weeksPerforming Laboratory
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CPT Code Information
82784
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SFIGS | IgG, S | 2465-3 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
IGG_S | IgG, S | 2465-3 |
AIGAS | IgG/Albumin, S | 6782-7 |
ALBQ | Albumin Quotient, CSF/Serum | 1756-6 |