Varicella-Zoster Virus DNA Detection by Real-Time PCR

CERNER / EPIC MNEMONIC:

VZVPCRRT

CPT CODE:

87798

TEST INFORMATION:

This test includes detection of Varicella-zoster virus.  Varicella-zoster virus in CSF.

DAYS PERFORMED:

Monday, Wednesday, and Friday

TURNAROUND TIME:

Maximum of 72 hours

SPECIAL INSTRUCTIONS:

Specimen should be received by the laboratory as soon as possible.

CONTAINER TYPE:

CSF collection tube ; M4 transport medium for swabs

COLLECTION:

Vesicular lesions:  Wash the surface of the vesicles with sterile saline.  Carefully open several vesicles and soak up the vesicular fluid with a clean sterile swab.   The specimen should be collected in the first three days of eruption.  Place the swab into M4 transport medium immediately after collection.
CSF:  Cerebrospinal fluid should be collected by a physician via lumbar puncture using standard sterile technique.

SPECIMEN REQUIREMENTS:

1 ml of CSF in a sterile tube from the lumbar puncture kit
Vesicular fluid on a swab in M4 viral transport media

REJECTION CRITERIA:

Dry swab; swab specimen not in M4 transport media; specimen not refrigerated prior to transport; specimen not received in a sterile sealed container; specimen not closed properly and leaked into transport bag; excessive delay in transport; inappropriate specimen container; specimen unlabeled or mislabeled.

MINIMUM VOLUME:

1 mL of CSF or one swab in M4 transport media

HANDLING INSTRUCTIONS:

The specimen should be transported to the lab as soon as possible.  When transportation is delayed, refrigerate.

REFERENCE RANGE:

No VZV detected.

LIMITATIONS OF TEST:

Reliable results are dependent on appropriate specimen collection, transport storage, and processing procedures.  No detection limits have been established for other specimen types or transport media.

METHODOLOGY:

Isolation of target and control DNA, real time PCR with detection by target specific probes for VZV and internal control.

ADDITIONAL INFORMATION:

The detection of Varicella-Zoster virus DNA is based upon the real-time amplification and detection of specific VZV genomic DNA sequences by PCR from total DNA extracted from the specimen.  Probes specific for VZV are used to identify and differentiate the products of the PCR amplification.
In house studies have shown the analytical sensitivity of this assay is 10 copies/PCR reaction and 250 copies/patient specimen.
The diagnosis of VZV infection should not rely solely upon the result of a PCR assay.  A positive PCR result should be considered in conjunction with clinical presentation and additional established diagnostic tests prior to establishing a diagnosis.  A negative PCR result indicates the absence of VZV DNA in a sample tested and does not exclude the diagnosis of disease.  
This test or one or more of its components was developed and its performance characteristics determined by RML Laboratories, Division of Clinical Microbiology.  It has not been cleared or approved by the U.S. Food and Drug Administration (FDA).  The FDA has determined that such clearance or approval is not necessary.  This test is performed pursuant to a license agreement with Roche Molecular Systems. Inc.

LAST UPDATED:

6-3-2014

TEST SYNONYM(S):VZV detection by real time PCR; VZV PCR; Varicella zoster virus by real time PCR; Herpes zoster