HIV resistance testing

Indications

• HIV1 infection
  • all HIV1 patients who enter care
    • even if immediate treatment is not planned
• HIV1 treatment failure

Laboratory

• see ARUP consult
• HIV phenotype may linke to Loincs of interest

Procedure

• genotype testing
  • identifies mutations present in HIV genes
    • reverse transcriptase
    • retroviral protease
    • integrase
  • identifies about 80% of resistant forms of HIV1
  • results available in about 1-2 weeks
  • generally 1st test: faster & cheaper than phenotype testing
• phenotype testing
  • measures ability of HIV to multiply in the presence of varying concentrations of drugs
  • involves recombination of genetic material in specimen obtained from patient with HIV laboratory clone
  • results available in 2-3 weeks

Notes

• may not be reliable if patient is not on antiretroviral therapy because resistance may not manifest without selective pressure of antiretroviral agents
• Sentosa SQ HIV Genotyping Assay is the first FDA-authorized test for HIV mutations that uses next-generation sequencing
  • > 95% sensitive & specific for detecting 342 HIV drug resistant mutations

More general terms

• HIV1 nucleic acid
• antibiotic sensitivity (Kirby-Bauer susceptibility testing)

More specific terms

• HIV integrase inhibitor mutation
• HIV nonnucleoside reverse transcriptase gene mutation
• HIV nucleoside reverse transcriptase gene mutation
• HIV protease gene mutation

Additional terms

• HIV phenotype [Susceptibility]
• HIV-1 coreceptor tropism (Trofile)
• human immunodeficiency virus-1 (HIV-1)