Frequently Asked Questions
What differentiates HerpeSelect from
other test kits?
Many laboratories offer HSV-1 or HSV-2 IgG antibody testing, but their tests are not able to deliver reliable type-specific results. Reactivity with shared, type-common antigens is almost always present to some degree, causing inaccurate results to be reported in up to 70% of positive patients. HerpeSelect 1 and 2 kits use glycoprotein G antigens -- gG1 (from HSV-1) and gG2 (from HSV-2) – the major antigens known to elicit type-specific antibody responses. HerpeSelect® HSV-1 and HSV-2 type-specific tests are for in vitro diagnostic use.
What is the difference between HerpeSelect
ELISA, Plexus HerpeSelect, HerpeSelect Immunoblot and HerpeSelect Express?
ELISA
HerpeSelect ELISA system consists of two micro-plate assays, one for detecting HSV-1 (gG1) IgG, and the other for HSV-2 (gG2) IgG. These tests are appropriate for high volume testing on automated platforms and individual antibody type testing.
- 2 separate kits for HSV-1 or HSV-2
- 96 test wells per kit in breakaway strips
- Numerical result
- CLIA highly complex
Immunoblot
HerpeSelect 1 & 2 Immunoblot IgG is like a simplified Western Blot with gG1 and gG2 bands, a type-common HSV band, and a serum control band all arrayed on a single strip. The test is read visually for HSV-1 and HSV-2 results so that instrumentation is not required. It is well suited for lower volume laboratory testing.
- 1 kit for both HSV-1 & HSV-2
- 24 test strips per kit
- Positive/Negative result visually read on nitrocellulose
strip
- CLIA rated moderately complex
Plexus HerpeSelect Multiplex
Plexus HerpeSelect is a multiplexed immunoassay for the qualitative detection and differentiation of human IgG antibodies to HSV-1 and HSV-2. The assay utilizes beads that fluoresce at different wavelengths and/or intensities: two distinct HSV glycoprotein G antigen beads (gG1 for HSV-1 and gG2 for HSV-2), as well as control beads. It is well suited for higher volume laboratories that have Luminex instrumentation.
- 1 kit for both HSV-1 & HSV-2
- Both results from 1 sample
- 96 tests per kit
- Positive/Negative result reported by Luminex system
HepeSelect Express
HerpeSelect Express is a rapid HSV-2 test that provides a lab quality serology result from a finger stick in about 15 minutes. Each single test cassette that provides a visual read of positive or negative HSV 2 test results. - Control included in cassette
- Buffer and sample pipette included with cassette
- CLIA rate moderately complex (Waiver pending)
What type of equipment is needed for HerpeSelect testing?
For the ELISA tests, 10uL, 100uL, 1mL and 5mL pipettes are needed. A microplatereader (450nm) is needed to read the ELISA test result. HerpeSelect is for in vitro diagnostic use on automated instrumentation. Performance characteristics should be established by the user for their equipment.
For the Immunoblot test, 15uL and 5mL pipettes are needed, as well as a platform rocker.
Plexus kits require a Luminex reader to calculate the median fluorescence intensity(MFI)
HerpeSelect Express requires lancets.
How long does it take to perform HerpeSelect testing?
Both ELISA and Immunoblot tests are performed in less than 3 hours. HerpeSelect Plexus HSV 1 and 2 results are available in less than 2 ½ hours. HerpeSelect Express HSV 2 results are available in about 15 minutes.
Is HerpeSelect Immunoblot a confirmatory test for HerpeSelect
ELISA?
No. Both formats exhibit sensitivity and specificity values ranging
from 91-100% in clinical trials with sexually active adults and
pregnant women.
How much does a HerpeSelect test cost?
For information on kit prices contact Focus Diagnostics at (800)
838-4548 for international customer.
Email dxcs@focusdx.com For information on HerpeSelect testing services from Focus Diagnostics clinical laboratory, call (800) 445-4032.
Is HerpeSelect reimbursed by payors?
Herpes type specific serology has established CPT codes for billing. Please check with your local Medicare branch or private payers for exact reimbursement amounts.
Medicare Part B, 2004
HSV-1 CPT Code 86695
HSV-2 CPT Code 86696
Can a patient order HerpeSelect Kits?
No. But, for more information on how to get HerpeSelect testing patients may contact Focus Diagnostics Customer Service at (800) 445-4032 (within the US), (714) 220-1900 or fax (714) 220-1820.
How long after infection will HerpeSelect detect IgG antibodies?
Recent studies show that HerpeSelect can detect HSV IgG antibodies as quickly as 3 weeks after onset of symptoms. However, it is important to note that all patients seroconvert at different rates. Some patients do not seroconvert for 6 months or longer.
What about HSV IgM testing?
The presence of IgM antibodies in HSV infections is difficult to interpret and may be confusing because unlike IgG, IgM is not type-specific. The presence of IgM may indicate a true primary infection however the test has low sensitivity and negative predictive value (NPV).(10) Additionally, the presence of IgM may be due to the reactivation of a latent HSV-1 or HSV-2 infection. For this reason, IgM testing is not recommended as a differential diagnostic tool, but may offer information about a particular patient’s antibody response.
What confirmatory testing is necessry for HepeSelect ELISA, Immunoblot and/or Express?
There is not supplemental or confirmatory testing required for HSV testing. Clinical judgment should always be considered when providing a patient with a diagnosis. It is the laboratory director’s decision which procedures should be followed if an unexpected result is given.
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