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HelpTest Code NSAIP Neurosyphilis IgG Antibody Index with VDRL, Serum and Spinal Fluid
Ordering Guidance
This test should be ordered in patients with suspected neurosyphilis who are confirmed seropositive in blood.
For syphilis testing on serum, order SYPH1 / Syphilis IgG with Reflex, Enzyme Immunoassay, Serum or SYPH2 / Syphilis IgG with Reflex, Enzyme Immunoassay, Serum.
Additional Testing Requirements
Although a small percentage of patients with neurosyphilis may be seronegative, it is recommended that all patients tested by this assay are first confirmed seropositive for syphilis in blood.
Specimen Required
Both spinal fluid (CSF) and serum are required for this test. CSF and serum must be collected within a maximum of 24 hours of each other.
Specimen Type: Spinal fluid
Container/Tube: Sterile vial
Specimen Volume: 2.2 mL
Collection Instructions:
1. The spinal fluid (CSF) specimen must be collected within 24 hours of the serum specimen, preferably at the same time.
2. The CSF aliquot should be from the second, third, or fourth CSF vial collected during the lumbar puncture. Do not submit CSF from the first vial due to the possibility of blood contamination, which will cause specimen rejection.
3. Label vial as spinal fluid or CSF.
4. Band CSF specimen together with the serum sample.
Specimen Type: Serum
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 2.2 mL
Collection Instructions:
1. Within 24 hours of collection of the spinal fluid specimen, a serum specimen must also be collected, preferably at the same time.
2. Centrifuge and aliquot serum into a plastic vial.
3. Label tube as serum.
4. Band serum specimen together with the CSF sample.
Useful For
Aid in the diagnosis of neuroinvasive syphilis
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| NSCSF | Neurosyphilis IgG Screen, CSF | No | Yes |
| NSSER | Neurosyphilis IgG, S | No | No |
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| NSAI | Neurosyphilis IgG, Ab Index | No | No |
| VDSFT | VDRL Titer,CSF | No | No |
Testing Algorithm
Testing begins with syphilis IgG screening of the spinal fluid (CSF) specimen. If the screen is negative, no additional testing will be performed.
If the CSF screen is reactive, the paired CSF and serum specimens will be used to establish the antibody index. To do this, the paired serum and CSF samples (collected within 24 hours of each other) are tested on the same run using quantitative assays to determine levels for the following analytes:
1. Anti-Treponema pallidum IgG in CSF and serum
2. Total IgG in CSF and serum
3. Albumin in CSF and serum
These additional tests are necessary to normalize the level of anti-T pallidum antibodies to total IgG and albumin in the CSF and establish the antibody index ratio of anti-T pallidum antibodies in CSF-to-serum. This testing is performed at an additional charge.
Samples that result as Syphilis Antibody Index negative do not undergo additional testing.
Samples that result as Syphilis Antibody Index positive or equivocal will be reflexed for VDRL testing to establish a semi-quantitative titer.
Reporting Name
Neurosyphilis IgG Ab Indx w/VDRLSpecimen Type
CSFSerum
Specimen Minimum Volume
Spinal fluid: 1.5 mL; Serum: 1.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| CSF | Refrigerated (preferred) | 10 days |
| Frozen | 10 days | |
| Serum | Refrigerated (preferred) | 10 days |
| Frozen | 10 days |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Spinal fluid (CSF) contaminated with blood | Reject |
Reference Values
NEUROSYPHILIS SCREEN, IgG, SPINAL FLUID:
Negative
Reference values apply to all ages.
NEUROSYPHILIS IgG ANTIBODY INDEX:
Antibody Index: 0.6-1.2
Reference values apply to all ages.
VDRL TITER, SPINAL FLUID:
Negative
Reference values apply to all ages.
Day(s) Performed
Monday through Sunday
Report Available
2 to 4 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86780
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| NSAIP | Neurosyphilis IgG Ab Indx w/VDRL | 58031-6 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| NSSER | Neurosyphilis IgG, S | 69048-7 |
| NSY1 | Neurosyphilis IgG, CSF | 58031-6 |
| NSY2 | Neurosyphilis IgG Interp | 69048-7 |