ACCEPTABLE SPECIMEN:
1. Dermal lesion/vesicle, mucosal lesion/vesicle, or eye swab.
2. Spinal fluid collected by lumbar puncture, ventricular or suboccipital tap, or through shunt.

Causes for Rejection:
1. Specimen not labeled with patient's name, MRN, date/time of collection, collector's initials.
2. Insufficient volume of CSF.
3. Patient over 2 y.o. with CSF protein <= 50 mg/dL and leukocyte count <= 5. Specimens from patients <= 2 y.o. will be tested regardless.
4. Specimens previously used by other laboratories - "shared" specimen not acceptable.
5. Calcium Alginate swab or any swab with a wooden shaft, or swab transported in gel.

Collect specimen as follows:
LESION:
1. Aseptically unroof lesion.
2. Firmly sample the base of lesion with a plastic shaft polyester swab moistened with sterile saline to collect infected epithelial cells.
3. Place swab into the tube of Viral Transport Media (VTM) breaking off shaft of swab, if necessary. Cap tube tightly.
4. Double-bag the labeled VTM tube and submit to the laboratory.

VESICLE:
1. Cleanse vesicle with sterile saline.
2. Carefully aspirate vesicle fluid with syringe. Alternatively, open the vesicle with a needle or a scalpel blade and use a plastic shaft polyester swab to collect fluid and cellular material by vigorously sampling the base of the lesion.
3. Place aspirated fluid into VTM tube. Alternatively, break off swab into VTM tube. Cap tube tightly.
4. Double-bag the labeled VTM tube and submit to the laboratory.

EYE:
1. Collect material from the lower conjunctiva with a flexible, fine-shafted polyester swab moistened with sterile saline.
2. Place the swab into the VTM tube and cap tightly.
3. Double-bag the labeled VTM tube and submit to the laboratory.

SPINAL FLUID:
1. Decontaminate skin with povidone iodine.
2. Perform sterile lumbar puncture; ventricular or suboccipital tap.
3. Send 1-5 mL of spinal fluid in a screw-capped, sterile collection tube.
4. Submit immediately to the laboratory.

SHUNT FLUID - CSF:
1. Decontaminate skin and catheter with povidone iodine.
2. Aseptically aspirate fluid through shunt.
3. Send 1-5 mL of shunt fluid in a screw-capped, sterile collection tube.
4. Submit immediately to the laboratory.


Note: Submit CSF in sterile specimen container (not VTM).

DELIVER IMMEDIATELY TO MICROBIOLOGY IN A TIGHTLY SEALED CONTAINER WITH NO EXTERNAL SPILLAGE. Refrigerate specimen if transport is delayed.

Causes for Rejection:
1. Specimen container leaking, contaminated, or delayed in transit.

Test is indicated for the evaluation of patients with signs or symptoms of aseptic meningitis and/or encephalitis. It is also indicated as an aid to diagnose VZV infection in patients with skin, mucosal, or ocular lesions. This assay should be used with other criteria including symptoms and clinical presentation.

Varicella zoster virus can cause a variety of diseases including chickenpox and shingles (skin lesions), ocular infections, encephalitis, meningitis, and disseminated disease in immunocompromised patients. Molecular methods are now the diagnostic gold standard owing to superior sensitivity and a more rapid turn around time as compared to culture.  The diagnosis of VZV infection is predicated on the clinical presentation in conjunction with detection of viral DNA in clinical specimens.  Early clinical recognition is important, because antiviral therapy should be initiated within 72 hours of symptom onset in order to maximize the potential benefits of treatment including relief of post-herpetic pain.
Occasionally, results will not be available due to inhibitory substances in the specimen (see limitations).

A negative result does not preclude active disease. Specimen collection technique in addition to the age of the lesion is likely to influence test performance.
Specimens grossly contaminated with blood, oral washes, or other substances may inhibit the PCR and produce false negative results. The high sensitivity of PCR amplification requires that the specimens be processed in an environment where contamination of the specimens by VZV DNA is not likely to occur.

Real-Time Polymerase Chain Reaction (PCR)

The performance of this PCR test was verified in the Clinical Microbiology Laboratory at Duke University Medical Center. This test is run in accordance with the Diasorin MDX package insert and as approved by the U.S. Food and Drug Administration.