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Test ID: LHSVZ    
Herpes Simplex Virus (HSV) and Varicella-Zoster Virus (VZV), Molecular Detection, PCR

Method Description Describes how the test is performed and provides a method-specific reference

Herpes Simplex Virus (HSV):

Viral nucleic acid is extracted from genital, dermal, and ocular specimens. Primers directed to the DNA polymerase gene of HSV produce 215-bp and 239-bp amplicons, respectively. The LightCycler instrument amplifies and monitors by fluorescence the development of target nucleic acid sequences after the annealing step during PCR cycling. This is an automated PCR system that can rapidly (30-40 minutes) detect amplicon development through stringent air-controlled temperature cycling and capillary cuvettes. The detection of amplified products is based on the fluorescence resonance energy transfer (FRET) principle. For FRET product detection, a hybridization probe with a donor fluorophore, fluorescein, on the 3' end is excited by an external light source and emits light that is absorbed by a 2nd hybridization probe with an acceptor fluorophore, LC-Red 640, at the 5' end. The acceptor fluorophore then emits a light of a different wavelength that can be measured with a signal that is proportional to the amount of specific PCR product. LightCycler hybridization probes were designed for HSV type 2, and sequence differences between HSV type 2 and HSV type 1 are detected by melting curve analysis. Melting curve analysis is performed following PCR amplification. Starting at 54 degrees C, the temperature in the thermal chamber is slowly raised to 95 degrees C, and the fluorescence is measured at frequent intervals. Sequence differences between the PCR product and hybridization probes result in shifts in the melting temperatures. (66.7 degrees C for HSV type 1 and 74.7 degrees C for HSV type 2) that are detected. Analysis of the PCR amplification and probe melting curves is accomplished through the use of LightCycler software.(Espy MJ, Uhl JR, Svien KA, et al: Laboratory diagnosis of herpes simplex virus infections in the clinical laboratory by LightCycler PCR. J Clin Microbiol 2000;38:795-799)

 

Varicella-Zoster Virus (VZV):

Viral nucleic acid is extracted from dermal specimens. Primers directed to gene 28 of VZV produce a 287 bp amplicon. The LightCycler instrument amplifies and monitors by fluorescence the development of target nucleic acid sequences after the annealing step during PCR cycling. This is an automated PCR system that can rapidly (30-40 minutes) detect amplicon development through stringent air-controlled temperature cycling and capillary cuvettes. The detection of amplified products is based on the fluorescence resonance energy transfer (FRET) principle. For FRET product detection, a hybridization probe with a donor fluorophore, fluorescein, on the 3' end is excited by an external light source and emits light that is absorbed by a second hybridization probe with an acceptor fluorophore, LC-Red 640, at the 5' end. The acceptor fluorophore then emits a light of a different wavelength that can be measured with a signal that is proportional to the amount of specific PCR product. Analysis of the PCR amplification is accomplished through the use of LightCycler software.(Espy MJ, Uhl JR, Svien KA, et al: Laboratory diagnosis of herpes simplex virus infections in the clinical laboratory by LightCycler PCR. J Clin Microbiol 2000;38:795-799)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Monday through Sunday

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

1 day/same day

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result

3 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 Days

Performing Laboratory Location The location of the laboratory that performs the test

Rochester