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Test Code INDEX CSF Cerebrospinal Fluid (CSF) IgG Index

Reporting Name

Cerebrospinal Fl, CSF, IgG Index

Useful For

As an aid in the diagnosis of multiple sclerosis

Specimen Required

Serum and spinal fluid are required. Specimens must be obtained within 1 week of each other.


Specimen Type: Serum

Container/Tube: Red top or serum gel

Specimen Volume: 1 mL

Collection Instructions: Label specimen as serum.


Specimen Type: Spinal fluid

Container/Tube: Sterile vial

Specimen Volume: 1 mL

Collection Instructions: Label specimen as spinal fluid.

Seattle Children's Hospital Note:

Collect 2.0 mL whole blood in Red top.

Specimen Type


Specimen Minimum Volume

Serum: 0.5 mL
Spinal Fluid: 0.5 mL

Specimen Stability Information

Specimen Type Temperature Time
CSF Refrigerated (preferred) 14 days
  Ambient  14 days
  Frozen  14 days
Serum Refrigerated (preferred) 14 days
  Ambient  14 days
  Frozen  14 days

Day(s) and Time(s) Performed

Monday through Saturday; 2 p.m.

Seattle Children's Hospital Note:

TAT: 3 - 4 days

Performing Laboratory

Mayo Medical Laboratories in Rochester

Method Name


Method Description

The cerebrospinal fluid (CSF) and serum IgG and albumin are determined by immunonephelometry on a Siemens Nephelometer II. The CSF IgG index and synthesis rate are calculated and reported. In addition, the serum IgG and albumin, CSF IgG and albumin, and serum and CSF IgG/albumin ratios are reported.(Instruction manual: Siemens Nephelometer II Operations. Siemens, Inc., Newark, DE)

Reference Values

CSF index: 0.00-0.85

CSF IgG: 0.0-8.1 mg/dL

CSF albumin: 0.0-27.0 mg/dL

Serum IgG

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

Serum albumin: 3,200-4,800 mg/dL

CSF IgG/albumin: 0.00-0.21

Serum IgG/albumin: 0.0-0.4

CSF IgG synthesis rate: 0-12 mg/24 hours

Test Classification

This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions.

CPT Code Information

82040-Albumin, serum

82042-Albumin, spinal fluid

82784 x 2-IgG, serum and spinal fluid

LOINC Code Information

Test ID Test Order Name Order LOINC Value
SFIN Cerebrospinal Fl, CSF, IgG Index In Process


Result ID Test Result Name Result LOINC Value
INDEX IgG Index, CSF 14117-6
IGG_S IgG, S 2465-3
ALB_S Albumin, S 1751-7
IGG_C IgG, CSF 2464-6
ALB_C Albumin, CSF 1746-7
AIGAS IgG/Albumin, S 6782-7
AIGAC IgG/Albumin, CSF 2470-3
SRATE Synthesis Rate, CSF 14116-8

Reject Due To



Serum: Mild OK; Gross OK



Serum: Mild OK; Gross reject



Serum: Mild OK; Gross OK



Profile Information

Test ID Reporting Name Available Separately Always Performed
SFINC IgG Index, CSF No Yes