Rheumatoid Arthritis HLA Association

Casandra

Casandra Test Code LC39434Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 167418CPT Code 81382

Rheumatoid Arthritis HLA Association

Clinical Use

Use

Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects the joints. Worldwide, the pervalence ranges between 0.5 to 1 percent and genetic factors play a role in RA risk, severity, and progression. The most important gene conferring risk for Anti-Citrullinated Protein Antibody positive (ACPA+) RA resides in the class II major histocompatibility complex (MHC) at the HLA-DRB1 locus. The HLA-DRB1 alleles that predispose to RA are the DRB1*04:01, *04:04, *04:05, *04:08, *01:01, *01:02, *09:01, *10:01 and *14:02 alleles, most of which possess a shared epitope (SE). These alleles increase the risk of RA in all populations, but the degree of predisposition may vary with different populations.

Special Instructions

If you have questions, please call 800-533-1037 (HLA customer service) for assistance selecting the proper HLA test for the patient.

Limitations

This test was developed and its performance characteristics were determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration, meaning its results should be interpreted in the context of clinical findings and not solely used to make a diagnosis. A negative result for the RA-associated DRB1 alleles does not preclude a diagnosis of RA in the individual tested. Testing schedules may vary, and in some cases, additional time should be allowed for reflex tests.

Test Details