HIV Genotypic Resistance Assay

General Information

Lab Name

Lab Code

HIVGRA

Epic Name

HIV Genotypic Resistance Assay

Description

Sanger sequencing is used to determine the nucleotide sequence of amplified HIV target regions, specifically the protease and reverse transcriptase (RT) genes. These genes are critical for HIV genotyping because mutations within the protease gene are associated with resistance to protease inhibitors, while mutations in the RT gene are linked to resistance to nucleoside and non-nucleoside reverse transcriptase inhibitors. The resulting sequence data are analyzed and submitted to the Stanford HIV Drug Resistance Database, which identifies known resistance-associated mutations and generates a genotype report. This report provides clinically relevant information to guide antiretroviral therapy selection by indicating which drugs the virus may be resistant or susceptible to.

Specimens with RNA levels below 20 copies/mL are rejected prior to RNA extraction. The assay has an approximate sensitivity of 1,000 copies/mL at a 95% confidence level.

This test was developed and its performance characteristics determined by the University of Washington Department of Laboratory Medicine and Pathology. It has not been cleared or approved by the US Food and Drug Administration.

For ordering: HIV Genotypic Resistance Assay for the integrase inhibitors (INSTIs).

HVINTA, HIV Integrase Resistance Assay [HVINTA]

Synonyms

HIV Antiviral Resistance Testing, HIVGRR

Components

Code	Name
HVGPAA	HIVGR, Protease Amino Acids
HVGPRM	HIVGR, Prot: Resist Mutations
HVGPOM	HIVGR, Prot: Other Mutations
HVGTAA	HIVGR, RT: Amino Acids
HVGTRM	HIVGR, RT: Resist Mutations
HVGTOM	HIVGR, RT: Other Mutations
HIVGRI	HIV Interp of Genotype
HGATV	Atazanavir (Reyataz) ATV
HGDRV	Darunavir (Prezista) DRV
HGLPV	Lopinavir_ritonavir (Kaletra) LPV
HGABC	Abacavir (Ziagen) ABC
HGAZT	Zidovudine (Retrovir) ZDV/AZT
HGFTC	Emtricitabine (Emtriva) FTC
HG3TC	Lamivudine (Epivir) 3TC
HGTDF	Tenofovir (Viread) TDF/TAF
HGDOR	Doravirine (Pifeltro) DOR
HGEFV	Efavirenz (Sustiva) EFV
HGETR	Etravirine (Intelence) ETR
HGNVP	Nevirapine (Virammune) NVP
HGRPV	Rilpivirine (Edurant) RPV
HGCOM	HIVGR, Comment

Interpretation

Method: Sequencing/Real-time Polymerase Chain Reaction.
Reference Range: See individual components

Ordering & Collection

Specimen Type: Blood
Collection: Blood: 6 mL blood in EDTA (LAVENDER TOP), SST, RED, or PEARL TOP (PPT).

Note: HIVGRA and HVINTA all test can be done on same 2 mL aliquot.

Unacceptable: GREEN TOP, Extracted nucleic acid from an outside laboratory.

Minimum sample requirement: 2 mL
Quantity: Requested: 2 mL plasma/serum
Minimum: 2 mL plasma/serum

Processing

Receiving Instructions: Blood: Separate plasma/serum from whole blood within 24 hours of collection. Freeze at -10°C or colder and ship on dry ice. If freezer and/or dry ice is not available, ship immediately at 2-8°C (ice pack). Sample may be stored at 2-8°C (ice pack) for up to 48 hours of collection. Samples stored at 2-8°C greater than 48 hours old may be rejected. Do not freeze/thaw.

Outside Laboratories: Centrifuge sample and remove plasma/serum. Send Frozen plasma/serum at -10°C or colder and ship on dry ice.

Misc Sendout

Performance

Lab Department

Central Lab Virology(RVIR)

Frequency

Wednesday set up. Results 14-21 days later.

Available STAT?

Performing Location(s)

CL	Infectious Disease Division (IDD) - Virology 1601 Lind Ave SW Renton, WA 98057	Phone: 206-685-6656 option 8 Hours of Operation: Mon–Fri: 7:00 AM–7:00 PM Sat: 9:00 AM–4:00 PM

Billing & Coding

CPT Codes: 87901
LOINC: 49660-4
Interfaced Order Code: UOW1051