HLA-B5801 Genotype, Allopurinol Hypersensitivity
Label Mnemonic: HLA58
Epic Lab Code: LAB8426
Downtime Form: A-1a Miscellaneous Request
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
Whole Blood
Collection Medium:
Lavender top tube 3 mL (EDTA)
Minimum:
Preferred Minimum: 3 mL Whole Blood in in Lavender top (EDTA) tube
Absolute Minimum: 0.35 mL Whole Blood in in Lavender top (EDTA) tube
Turn Around Time:
1 day upon receipt at reference laboratory (Not reported Saturday or Sunday)
Reference Range:
An interpretive report will be provided.
Interpretive Data:
Positivity for HLA-B*58:01 confers increased risk for hypersensitivity to allopurinol.
Comments:
This test is to assess genetic risk for allopurinol hypersensitivity in patients of Han Chinese ancestry, or those with renal insufficiency of Korean ancestry.

Useful For: Identifying individuals with an increased risk of severe cutaneous adverse reactions to allopurinol based on the presence of the human leukocyte antigen HLA-B*58:01 allele.

Cautions: Samples may contain donor DNA if obtained from patients who received heterologous blood transfusions or allogeneic blood or marrow transplantation. Results from samples obtained under these circumstances may not accurately reflect the recipient's genotype. For individuals who have received blood transfusions, the genotype usually reverts to that of the recipient within 6 weeks. The impact of blood or marrow transplantation on risk of severe cutaneous adverse reactions with allopurinol is not defined in the literature.

Rare or novel variants may be present that could lead to false- negative or false-positive results. This assay also detects closely related rare alleles including HLA-B*57:05, *58:04, *58:05, *58:09, *58:10, *58:11, *58:12, *58:13, *58:15, *58:17, *58:19, *58:21, *58:22, *58:23, *58:24, and *58:28. There are currently no data indicating whether these or any other alleles or subtypes are associated with allopurinol-induced severe cutaneous adverse reactions.

Please print, complete and submit the Informed Consent for Genetic Testing from the Mayo Medical Laboratories with the specimen and the A-1a Miscellaneous Request.
Methodology:
Qualitative Allele-Specific Real-Time Polymerase Chain Reaction (PCR)
CPT Code:
81381