Varicella-Zoster Virus DNA, Quantitative Real-Time PCR

Test Code
VZPCRQT


Quest Code
19493


CPT Codes
87799

Preferred Specimen
1 mL whole blood collected in an EDTA (lavender-top) tube or
1 mL CSF collected in a sterile plastic leak-proof container


Minimum Volume
0.3 mL


Transport Temperature
Refrigerated (cold packs)


Specimen Stability
Whole blood
Room temperature: 48 hours
Refrigerated: 7 days
Frozen: Unacceptable

All other samples
Room temperature: 48 hours
Refrigerated: 7 days
Frozen: 30 days


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Heparin whole blood


Methodology
Real-Time Polymerase Chain Reaction

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Set up: Mon-Sat; Report available: 1-2 days


Reference Range
Varicella Zoster Virus DNA, QN RT PCRNot Detected (copies/mL)
Varicella Zoster Virus DNA, QN RT PCRNot Detected (Log copies/mL)


Clinical Significance
This test is used for detection and quantification of Varicella-Zoster Virus (VZV) DNA in spectrum of clinical samples in individuals suspected or presenting with signs and symptoms of clinical VZV infection. Quantitative VZV PCR results can aid in diagnosis and assessing treatment response of visceral varicella in immunocompromised patients, as well as determining the severity of neurological disease due to VZV infection.

VZV is a member of the Herpesviridae family that causes two distinct clinical diseases in the infected individual. Varicella, or more commonly chickenpox, is the primary infection and is characterized by a generalized exanthematous rash. After primary infection, VZV characteristically becomes latent. Reactivation of the virus results in herpes zoster, or shingles, which is characterized by a vesicular rash limited to single dermatomes and is often associated with pain and paresthesia. Noncutaneous sites of VZV involvement after chickenpox or reactivation most frequently involve the central nervous system (CNS) and are manifested as acute cerebellar ataxia, encephalitis, meningitis, transverse myelitis, or Reye syndrome. Varicella pneumonitis is a serious complication of chickenpox that may be manifested as tachypnea, cough, dyspnea, and fever. VZV infection in immunocompromised individuals often leads to progressive disease state with involvement of multiple organs, including the lungs, liver, eyes, and central nervous system.

This assay can measure viral loads as low as 500 copies/mL and as high as 2,000,000 copies/mL. The virus may also be detected at less than the measurable amount; these results will be reported as "<500, Detected".


Performing Laboratory
Quest Diagnostics Nichols Institute
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042



The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.