Lyme Central Nervous System Infection IgG with Antibody Index Reflex, Serum and CSF
Test Mnemonic
LYMCNS
CPT Codes
- 86618 - QTY (1)
Includes
- Lyme CNS Infection IgG, CSF
- Lyme CNS Infection IgG Interp
- Lyme CNS Infection IgG, S
Performing Laboratory
Mayo Clinic Dpt of Lab Med & Pathology
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1.2 mL | Cerebrospinal fluid (CSF) | Sterile container | Refrigerated | Both CSF and serum are required for this test and must be collected within the same 24-hour period. Aliquot CSF from tube 2, 3, or 4. Rubber band together with serum if collected at the same time. | |
| 1.2 mL | Serum | SST (Gold) | Refrigerated | Both CSF and serum are required for this test and must be collected within the same 24-hour period. Rubber band together with CSF if collected at the same time. |
Stability
| Environmental Condition | Description |
|---|---|
| Refrigerated | 11 days |
| Frozen | 35 days |
| Ambient | Unacceptable |
Days Performed
Mon, Wed, Fri
Turnaround Time
1 - 5 days
Methodology
| Name | Description |
|---|---|
| Enzyme-Linked Immunosorbent Assay (ELISA) |
Reference Range
Special Info
Both CSF and serum are required for this test. CSF and serum must be collected within 24 hours (maximum) of each other and be rubber banded together prior to being sent to the performing laboratory. This test begins with IgG screening of the CSF specimen. If the screen is negative, no additional testing will be performed. If the screen is positive, the paired CSF and serum specimens will be used to establish the antibody index at additional cost. The additional quantitative assays determine levels for anti-Borrelia species IgG levels in CSF and serum, total IgG in CSF and serum, and albumin in CSF and serum. Grossly hemolyzed or lipemic specimens will be rejected. CSF contaminated with blood will be rejected. This test is New York state approved.
Clinical Info
This test is useful for aiding in the diagnosis of neuroinvasive Lyme disease or neuroborreliosis due to Borrelia species associated with Lyme disease. It compares the level of IgG antibodies to Lyme disease-causing Borrelia species in spinal fluid (CSF) and serum. The level of anti-Borrelia species IgG is normalized to total IgG and albumin in CSF and serum. This test can help identify whether the presence of IgG to Borrelia species in the CSF is due to true intrathecal antibody synthesis, suggesting neuroinvasive Lyme disease, versus antibody presence due to passive diffusion through the blood-brain barrier or, possibly, due to blood contamination of the CSF as a result of a traumatic lumbar puncture.
Clinical Limitation
A single negative result should not be used to exclude the diagnosis of neuroinvasive Lyme disease in a patient with appropriate exposure history and symptoms suggestive of infection.
Reflex Tests
The following additional test(s) may be ordered depending on results: