Ordering Recommendation

Standard of care prior to abacavir therapy per FDA. Predicts risk of abacavir hypersensitivity syndrome. Relevant to most populations.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature


Unacceptable Conditions

Plasma or serum. Heparinized specimens. Frozen specimens in glass collection tubes.


Ambient: 72 hours; Refrigerated: 1 week; Frozen: 1 month.


Polymerase Chain Reaction/Fluorescence Monitoring




5-10 days

Reference Interval

By report

Interpretive Data

Background Information for HLA-B*57:01 for Abacavir Sensitivity:
Abacavir sulfate is a nucleoside reverse transcriptase inhibitor (NRTI) used for the treatment of HIV.
Abacavir hypersensitivity reaction is characterized by fever, rash, malaise, gastrointestinal, and respiratory symptoms.
Symptoms typically appear within the first six weeks of treatment, worsen with each subsequent abacavir dose, and may be severe or fatal.
Autosomal dominant.
Abacavir hypersensitivity is strongly associated with the HLA-B*57:01 allele. The mechanism is related to drug-specific activation of T lymphocyte killer cells.
Allele Tested:
Presence or absence of the HLA-B*57:01 allele.
Allele Frequency: Southwest Asian 11 percent, Other Asian 0-6.7 percent, European 6.8 percent, South American 2.6 percent, Middle Eastern 2.5 percent, Mexican 2.2 percent, African 1 percent.
Clinical Sensitivity: 100 percent for immunologically confirmed hypersensitivity reaction.
Polymerase Chain Reaction (PCR) and Fluorescence Monitoring.
Analytical Sensitivity and Specificity:
Greater than 99 percent.
Alleles other than HLA-B*57:01 will not be evaluated. This test does not distinguish between heterozygote and homozygote carriers. Diagnostic errors can occur due to rare sequence variations. Risk of therapeutic failure or adverse reactions with abacavir may be affected by genetic and non-genetic factors that are not detected by this test. This result does not replace the need for therapeutic drug or clinical monitoring.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Compliance Category

Laboratory Developed Test (LDT)


Hotline History


CPT Codes



Component Test Code* Component Chart Name LOINC
2002431 HLA-B*57:01 Specimen 31208-2
2002432 HLA-B*57:01 Allele 50956-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • Abacavir hypersensitivity genotyping
  • Abacavir Sensitivity
  • HLA-B 5701 Genotype, Abacavir Hypersensitivity, Saliva
HLA-B*57:01 for Abacavir Sensitivity