West Nile Virus IgM, CSF
Test Mnemonic
CWESTM
CPT Codes
- 86788 - QTY (1)
LOINC ®
39573-1
Includes
- West Nile Virus IgM
Performing Laboratory
ARUP
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Cerebrospinal fluid (CSF) | Sterile container | Refrigerated |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.3 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | 8 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year (Avoid repeated freeze/thaw cycles) |
Days Performed
Sun, Tues, Fri
Turnaround Time
2 - 7 days
Methodology
| Name | Description |
|---|---|
| Semi Quantitative Enzyme Linked Immunosorbent Assay |
Reference Range
| West Nile Virus IgM | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| 0.89 IV or less: Negative - No significant level of West Nile virus IgM antibody detected. | 0.90-1.10 IV: Equivocal - Questionable presence of West Nile virus IgM antibody detected. Repeat testing in 10-14 days may be helpful. | 1.11 IV or greater: Positive - Presence of IgM antibody to West Nile virus detected, suggestive of current or recent infection. |
Special Info
Bacterially contaminated, heat-inactivated, hemolyzed or xanthochromic specimens will be rejected. If possible, specimens from New York clients will be sent out to a New York DOH approved laboratory.
Clinical Info
This test is intended to be used as a semi-quantitative means of detecting West Nile virus-specific IgM in CSF specimens in which there is a clinical suspicion of West Nile virus infection. This test should not be used solely for quantitative purposes, nor should the results be used without correlation to clinical history or other data. Because other members of the Flaviviridae family, such as St. Louis encephalitis virus, show extensive cross-reactivity with West Nile virus, serologic testing specific for these species should be considered. The detection of antibodies to West Nile virus in cerebrospinal fluid may indicate central nervous system infection. However, consideration must be given to possible contamination by blood or transfer of serum antibodies across the blood-brain barrier.