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HelpTest Code VZM Varicella-Zoster Virus (VZV) Antibody, IgM, Serum
Reporting Name
Varicella-Zoster Ab, IgM, SUseful For
Diagnosing acute-phase infection with varicella-zoster virus
Method Name
Immunofluorescence Assay (IFA)
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Specimen Type
SerumSpecimen Required
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 a plastic vial.
Specimen Minimum Volume
0.2 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 |
| Heat-inactivated specimen | Reject |
Reference Values
Negative
Reference values apply to all ages.
Day(s) Performed
Monday through Sunday
CPT Code Information
86787
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| VZM | Varicella-Zoster Ab, IgM, S | 43588-3 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 80964 | Varicella-Zoster Ab, IgM, S | 43588-3 |
Clinical Information
Varicella-zoster virus (VZV), a herpes virus, causes 2 distinct exanthematous (rash-associated) diseases: chickenpox (varicella) and herpes zoster (shingles). Chickenpox is a highly contagious, though typically benign, disease, usually contracted during childhood. Chickenpox is characterized by a dermal vesiculopustular rash that develops in successive crops approximately 10 to 21 days following exposure.(1) Although primary infection with VZV results in immunity and protection from subsequent infection, VZV remains latent within sensory dorsal root ganglia and upon reactivation, manifests as herpes zoster or shingles. During reactivation, the virus migrates along neural pathways to the skin, producing a unilateral rash, usually limited to a single dermatome. Shingles is an extremely painful condition typically occurring in older nonimmune adults or those with waning immunity to VZV and in patients with impaired cellular immunity.(2)
Several populations are at risk of suffering unusually severe reactions to VZV infections. The infection in pregnant women may spread through the placenta to the fetus causing congenital disease in the infant. Immunocompromised patients in hospitals may contract severe nosocomial infections from others who have active VZV infections and are at risk for developing severe VZV-related complications, which include cutaneous disseminated disease and visceral organ involvement.(2,3) Therefore, serologic screening of direct healthcare providers (physicians, allied healthcare personnel) and individuals in high-risk groups is necessary to avoid uncontrolled spread of infection.
While the clinical presentation of VZV infection is generally characteristic, serologic evaluation of patients with atypical and systemic infections is often required. For example, it is extremely important to serologically evaluate patients for the early detection of VZV infections in hospital settings. Nosocomial spread of VZV infection can be life-threatening to immunocompromised patients susceptible to infection.
Interpretation
A positive IgM result indicates a recent infection with varicella-zoster virus (VZV).
A negative result does not rule out the diagnosis of VZV infection. The specimen may have been drawn before the appearance of detectable antibodies. Negative results in suspected early VZV infection should be followed by testing a new specimen in 2 to 3 weeks.
Cautions
The performance characteristics with individuals vaccinated with varicella-zoster virus (OKA strain) have not been established.
The test must be performed on serum. The use of whole blood, plasma, or cord blood has not been established.
Positive results from cord blood or neonates should be interpreted with caution.
Results from immunocompromised patients should be interpreted with caution.
Method Description
The presence or absence of IgM-class antibody to varicella-zoster virus (VZV) is determined by an indirect immunofluorescence assay. Serum is incubated with VZV antigen that is adhered to a glass microscope slide. Antibodies, if present, will bind to the antigen forming stable antigen-antibody complexes. If no antibodies are present, the complexes will not be formed, and the serum components will be washed away. Fluorescein-labeled antihuman-IgM antibody is added to the reaction side and binds to IgM antibodies if present. This results in a positive reaction of bright apple-green fluorescence when viewed with a fluorescence microscope.(Package insert: Bion Varicella Zoster Antigen Substrate Slide. Bion Enterprises; 09/2019)