THE ROLE OF HLA TYPING IN RHEUMATIC DISEASES

Luca Mascaretti; Elena Bevilacqua

doi:10.33602/mebm.3.1.1

Luca Mascaretti HLA Typing Laboratory, Transfusion Medicine Department, Ospedale di Cattinara, Azienda Sanitaria Universitaria Giuliano Isontina
Elena Bevilacqua HLA Typing Laboratory, Transfusion Medicine Department, Ospedale di Cattinara, Azienda Sanitaria Universitaria Giuliano Isontina

DOI: https://doi.org/10.33602/mebm.3.1.1

Keywords: HLA, rheumatoid arthritis, spondyloarthritis, juvenile idiopathic arthritis

Abstract

Association between HLA-DR4 and rheumatoid arthritis (RA) has been known for 4 decades, and amino acid sites within HLA-DRB1 (11/13, 71, 74) are highly associated with RA. HLA is not useful for diagnosis or prognosis, but it may help predict severe and erosive disease. Since 90% of patients with ankylosing spondylitis (AS) and 50-70% of other spondyloarthritis (SpA) patients are HLA-B*27 positive, HLA is a stronghold of diagnostic algorithms. Genetic predisposition to juvenile idiopathic arthritis (JIA) is mainly due to HLA class II, and to a lesser extent to HLA class I. Although HLA plays a role in rheumatic disorders, its clinical relevance is not homogeneous. When classical biomarkers are lacking or in complex cases, HLA typing may provide support for the management of patients.