Lab Test

Human Immunodeficiency Virus Genotyping for Drug Resistance (HIV-1)

Test Codes

EPIC: LAB6883, Beaker: XHIVG, Warde: HIVTO


Send Outs


Note: HIV-1 Viral Load must be at least 1000 copies/mL to perform this test.

Specimen Collection Criteria

Collect: Two Lavender-top EDTA tubes.

Physician Office/Draw Specimen Preparation

Centrifuge to separate plasma from cells within 24 hours of collection. Transfer plasma to a plastic transport tube and freeze (-20°C/-4°F or below).

Preparation for Courier Transport

Transport: 4.0 mL plasma, frozen (-20°C/-4°F or below). (Minimum: 1.2 mL)

Rejection Criteria

Specimens not collected and processed as indicated.

  • Gross hemolysis
  • Whole blood
  • Gross lipemia
  • Heparinized blood
  • Serum

In-Lab Processing

Centrifuge to separate plasma from cells within 24 hours of collection. Transfer plasma to a plastic transport tube and freeze (-20°C/-4°F or below).

Transport: 4.0 mL plasma, frozen (-20°C/-4°F or below). (Minimum: 1.2 mL) 

NOTE: Send to Royal Oak on "RYO CPPRO Frozen Packing List" to be sent to Warde.


Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 24 hours
Refrigerated (2-8°C or 36-46°F): 6 days
Frozen (-20°C/-4°F or below): 42 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.


Sent to Warde Medical Laboratory, Ann Arbor, MI. Forwarded to Quest Diagnostics Lab.


Monday – Saturday.
Results available in 7-12 days.

Reference Range

By report.

Test Methodology

Reverse Transcription – Polymerase Chain Reaction (RT-PCR) and DNA Sequencing.


The recent availability of potent antiretroviral drugs has greatly improved the treatment of individuals infected with HIV. However, due to the high mutation rate of the virus, resistance to these drugs may develop, correlating with clinical progression as defined by commonly accepted endpoints, such as increased viral loads and decreased CD4+ cell counts. As drug resistance becomes more common so does the percentage of newly positive people infected with viral strains already drug resistant.

Clinical Utility

This test is useful for monitoring the drug resistance profiles in patients undergoing antiviral therapy for HIV-1 infection. This assay detects mutations in the HIV viral genes that encode the HIV protease, reverse transcriptase, and integrase.

Clinical Disease

Primary HIV infections are symptomatic in 50 - 70% of patients. These patients present with a variety of symptoms including Influenza-like or mononucleosis-like illness to more severe neurological symptoms. These symptoms may persist for a few days or up to two months. Rapid progression to AIDS is seen in patients that experience a longer acute illness. Most patients however, remain asymptomatic for 1 to greater than 10 years before the clinical symptoms of AIDS present.

Disease Reporting

This is a reportable infection and positive results will be reported to the Oakland County Health Department. For more information on reportable diseases, contact the Epidemiology Department at 248-551-4040.


HIV-1 causes a worldwide pandemic of acquired immunodeficiency syndrome and AIDS-related complex. In 1995, the World Health Organization estimated that 18 million adults and 1.5 million children are infected with HIV resulting in 4.5 million AIDS cases worldwide.

Incubation Period

The median time from HIV infection to AIDS is 8 – 10 years. Homosexual men and some neonates may progress to AIDS more rapidly than other groups.


HIV-1 is transmitted by blood, blood products, and body fluids. Major modes of HIV-1 transmission include sexual intercourse, parenteral transmission through shared or inadequately sterilized needles, transfusion of HIV-1 infected blood and blood factor concentrates, and mother - to - child transmission either in utero, at birth, or through breast feeding.

CPT Codes

87900, 87901, 87906.
LOINC:  48558-1


Last Updated


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