Arbovirus IgM EIA, St. Louis Encephalitis and West Nile
Laboratory Fee Schedule
Procedure: MZZ0085A
CPT: 86653, 86789
| Synonym(s): |
Flavivirus, Arbovirus IgM, SLEV IgM, WNV IgM |
| Requisition Form |
G-2A. |
| Test Description |
Capture Enzyme Immunoassay for the detection of IgM Antibodies to West Nile and St. Louis Encephalitis Viruses. |
| Pre-Approval Needed |
N/A |
| Supplemental Information Required |
N/A |
| Supplemental Form(s) |
N/A |
| Performed on Specimens from (sources) |
Human |
| Sample/Specimen Type for Testing |
- Serum 1.0 ml
- Cerebral Spinal Fluid (CSF) 400 uL
|
| Minimum Volume/Size Required |
- Serum 1.0 mL
- Cerebral Spinal Fluid (CSF) 400 µL
|
| Storage/Preservation Prior to Shipping |
- Store specimens at 2°C to 8°C for up to 48 hours.
- For storage longer than 48 hours, store at -20°C or below.
|
| Transport Medium |
N/A |
| Specimen Labeling |
- Two patient-specific identifiers required on specimen (e.g., patient full name, date of birth, medical record number).
- Three patient identifiers are preferred.
- Patient identifiers on specimen label must exactly match identifiers on submission form (e.g., abbreviated name on label and full name on form is not acceptable.)
- Additional DSHS Laboratory specimen labeling guidelines available online here.
|
| Shipping and Specimen Handling Requirements |
- Ship according to Dangerous Goods Regulations, IATA, and/or CFR 49.
- Category B Biological Substance, UN3373 shipping requirements apply.
- Handle as infectious agent using universal precautions.
- Triple' contain in accordance with federal shipping regulations for infectious agents.
- Submitters are responsible for packaging and shipping specimens according to regulatory requirements.
- Additional DSHS Laboratory specimen shipping guidelines online here.
- If specimens will arrive at the Lab within 48 hours of collection, refrigerate at 2°C –8°C and ship overnight on cold packs.
- If specimens will arrive at the Lab more than 48 hours after time of collection, freeze at -20°C or colder, and ship overnight on dry ice.
|
| Method |
IgM Antibody Capture Enzyme-Linked Immunosorbent Assay (MAC-ELISA). |
| Turn-around Time |
8 working days. |
| Interferences/Limitations |
- Reliable results are dependent on adequate specimen collection.
- Cross-reactions can occur between flaviviruses.
- Specific IgG can compete with IgM and may result in a false negative.
- Rheumatoid factor in presence of specific IgG may result in a false positive.
|
| Common Causes for Rejection |
- Insufficient quantity
- Unacceptable specimen type or source
- Improper shipping conditions
- Expired media or collection container
- Expired reagents/media/collection container.
- Discrepancies between G-2V submission form and specimen label.
- Missing/incomplete/illegible submission form or label.
|
| Additional Information |
- Results serve only as an aid in diagnosis and should be interpreted in relation to patient travel history, clinical symptoms, other diagnostic findings, and epidemiological data.
- The absence of detectable IgM antibody does not rule out the possibility of recent or current infection.
- Convalescent serum specimen should be tested if an early acute CSF or serum is negative.
- For most, IgM is detectable 8 days post-onset of symptoms and can persist for at least 45 days and sometimes for up to 90 days.
- Reactive samples will be forwarded to CDC for confirmatory testing by Plaque Reduction Neutralization Test (PRNT).
- Minimum volume for CDC confirmation testing is 0.5 mL.
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