Test Code LAB4884 Varicella-Zoster Virus (VZV) DNA Detection by PCR
Methodology
Polymerase Chain Reaction (PCR) performed on the DiaSorin Molecular - Liason Dx Integrated Cycler
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Specimen Requirements
Acceptable Specimens:
Whole blood (lavender-top/EDTA tube), Swab in viral transport medium, or CSF
Collection Procedure:
Blood
1. Draw blood into lavender-top/EDTA tube. Avoid hemolysis.
2. Maintain sterility and forward promptly at ambient temperature only.
For BJH Patients: Laboratory medicine resident review and approval is required for blood specimen requests.
Swab
1. Obtain a vial of universal/viral transport medium (UTM) with collection swab
2. Collect specimen
3. Place the swab in labeled UTM vial, break off shaft of swab and discard excess piece of shaft. To prevent leaking, make sure the swabs do not interfere with tightening cap on vial.
Note:
1. Specimen source is required
CSF
1. Aseptically collect ≥1 mL of CSF.
2. Place in a leak-proof screw-capped, sterile container.
3. Maintain sterility and forward promptly.
4. If transport is delayed, refrigerate specimen.
For BJH Patients: Laboratory medicine resident review and approval is required for CSF specimen requests.
Specimen Requirements Additional Information
Blood- Ambient/Refrigerate/Frozen OK
Swabs- Ambient/Refrigerate/Frozen OK
CSF- Ambient/Refrigerate/Frozen OK
Refrigerated specimens must be tested within 7 days
Frozen specimens must be tested within 30 days
Reference Values
Negative
Day(s) Test Set Up
Monday through Sunday
Turnaround Time:
STAT: not available
Routine: 1- 3 days, Final report available the day of testing
Test Classification and CPT Coding
Test Classification:
This assay is FDA cleared for performance on lesion swabs and CSF and has also been evaluated by the Barnes Jewish Molecular Infectious Disease Laboratory for performance on whole blood.
Assay Limit of Detection:
Whole Blood: 500 copies/mL
CSF: 1,500 copies/mL
Swabs: 3,500 copies/ml
Limitations:
-The detection of viral nucleic acid is dependent upon proper sample collection, transport, handling and storage. Failure to observe proper procedures in any one of these steps can lead to incorrect results.
-False-negative results may occur if the viruses are present at a level that is below the analytical sensitivity of the assay or if the virus has genomic mutations, insertions, deletions, or rearrangements or if performed very early in the course of illness.
-Most adults have been exposed to VZV at some point during their lifetime and can transiently have detectable virus from different sample types with or without symptomatology. Positive results should be interpreted in the appropriate clinical context.
CPT Code:
87798
Additional Information
For BJH Laboratory Use Only
Minimum Volume:
Blood: 1 mL of EDTA
CSF: 0.5 mL
Laboratory Processing Instructions:
BJH Microbiology will forward to the performing laboratory.