Test Code LAB7464 Arbovirus Antibody Panel, IgG and IgM, Serum
Additional Codes
ARBOP
Useful For
Aiding the diagnosis of arboviral encephalitis (California [LaCrosse], St. Louis, Eastern equine, and Western equine encephalitis)
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
CAVP | Calif Virus (LaCrosse)IgG and IgM,S | Yes | Yes |
EEEP | East Equine Enceph Ab, IgG and IgM, S | Yes | Yes |
STLP | St. Louis Enceph Ab, IgG and IgM, S | Yes | Yes |
WEEP | West Equine Enceph Ab,IgG and IgM,S | Yes | Yes |
Method Name
Immunofluorescence Assay (IFA)
Specimen Type
SerumOrdering Guidance
This panel tests for 4 arboviruses; to test for a specific arbovirus, the following tests are individually orderable:
-CAVP / California Virus (La Crosse) IgG and IgM, Serum
-EEEP / Eastern Equine Encephalitis Antibody, IgG and IgM, Serum
-STLP / St. Louis Encephalitis Antibody, IgG and IgM, Serum
-WEEP / Western Equine Encephalitis Antibody, IgG and IgM, Serum
Specimen Required
Supplies: Sarstedt Aliquot Tube 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Specimen Minimum Volume
0.15 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 14 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Reference Values
CALIFORNIA VIRUS (La CROSSE) ENCEPHALITIS ANTIBODY
IgG: <1:10
IgM: <1:10
Reference values apply to all ages.
EASTERN EQUINE ENCEPHALITIS ANTIBODY
IgG: <1:10
IgM: <1:10
Reference values apply to all ages.
ST. LOUIS ENCEPHALITIS ANTIBODY
IgG: <1:10
IgM: <1:10
Reference values apply to all ages.
WESTERN EQUINE ENCEPHALITIS
IgG: <1:10
IgM: <1:10
Reference values apply to all ages.
Interpretation
In patients infected with these or related viruses, IgM class antibody is reliably detected within 1 to 3 weeks of onset, peaking and rapidly declining within 3 months. Results from a single serum specimen can differentiate early (acute) infection from past infection with immunity if IgM is positive (suggests acute infection).
IgG antibody is generally detectable within 1 to 3 weeks of onset, peaking within 1 to 2 months, and declining slowly thereafter. A single serum specimen IgG of 1:10 or greater indicates exposure to the virus. A 4-fold or greater rise in IgG antibody titer in acute and convalescent sera indicates recent infection.
In the United States, it is unusual for any patient to show positive reactions to more than 1 of the arboviral antigens, although Western equine encephalitis and Eastern equine encephalitis antigens will show a noticeable cross-reactivity.
Method Description
The indirect immunofluorescent antibody (IFA) assay is a 2-stage "sandwich" procedure. In the first stage, the patient serum is diluted in Pretreatment Diluent for IgM and phosphate buffered saline (PBS) for IgG, added to appropriate slide wells in contact with the substrate, and incubated. Following incubation, the slide is washed in PBS, which removes unbound serum antibodies. In the second stage, each antigen well is overlaid with fluorescein-labeled antibody to IgM and IgG. The slide is incubated allowing antigen-antibody complexes to react with the fluorescein-labeled anti-IgM and anti-IgG. After the slide is washed, dried, and mounted, it is examined using fluorescence microscopy. Positive reactions appear as cells exhibiting bright apple-green cytoplasmic fluorescence against a background of red negative control cells. Semi-quantitative endpoint titers are obtained by testing serial dilutions of positive specimens.(Package inserts: Arbovirus IFA IgM and Arbovirus IFA IgG Instructions for Use; Focus Diagnostics; Rev. 03, 02/17/2023)
Day(s) Performed
Monday through Friday
Report Available
Same day/1 to 4 daysSpecimen Retention Time
2 weeksPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
86651 x 2-California virus (La Crosse) encephalitis antibody, IgG and IgM
86652 x 2-Eastern equine encephalitis antibody, IgG and IgM
86653 x 2-St. Louis encephalitis antibody, IgG and IgM
86654 x 2-Western equine encephalitis antibody, IgG and IgM
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ARBOP | Arbovirus Ab Panel IgG and IgM, S | 49093-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
8764 | Calif (LaCrosse) Encep Ab, IgG, S | In Process |
83354 | East Equine Enceph Ab, IgG, S | In Process |
8182 | St. Louis Enceph Ab, IgG, S | In Process |
8193 | West Equine Enceph Ab, IgG, S | 6957-5 |
87279 | West Equine Enceph Ab, IgM, S | In Process |
87268 | St. Louis Enceph Ab, IgM, S | In Process |
83355 | East Equine Enceph Ab, IgM, S | In Process |
87280 | Calif (LaCrosse) Encep Ab, IgM, S | In Process |
Forms
If not ordering electronically, complete, print, and send Infectious Disease Serology Test Request (T916) with the specimen.