Human leukocyte antigen-B alleles in spondyloarthritides: A single-center, prospective, cross-sectional study

Abstract

Objective: The objective of this study is to study distribution of human leukocyte antigen (HLA)-B alleles in Spondyloarthritis (SpA) and to find its clinical relevance in the patient management.Materials and Methods: A prospective, cross-sectional, pilot study was carried out on 100 participants at the single center of Northern India (Sir Ganga Ram Hospital, New Delhi). Assessment in ankylosing spondylitis (ASAS) classification criteria for axial/peripheral spondyloarthritis (SPA) (conventionally AS-ankylosing spondylitis), classification criteria for reactive arthritis (ReA), and CASPAR (classification criteria for psoriatic arthritis) criteria for psoriatic arthritis were used to sub-classify patients. Inflammatory bowel disease (IBD) patients who classified for ASAS criteria for SPA were classified as IBD-related SPA. Demographic data, disease characteristics, and relevant investigations were noted. HLA-B genotyping was carried out by the polymerase chain reaction method. HLA-B genotyping of 100 healthy kidney transplant donors were taken as controls. Fisher's exact test was used. P < 0.05 was considered as statistically significant.Results: Out of 100 patients, 58 were male and 42 were female. SPA (AS), ReA, PSA, and IBD-related SPA were 65, 12, 16, and 07, respectively. HLA-B 27+ve participants were 57. HLA-B40 and HLA-B52 were present in 25 and 19 participants, respectively. HLA-B27 allele was associated with SPA, PSA, and IBD-related SPA (P < 0.01, 0.034, and 0.037, respectively). In HLA-B27-ve cases, the frequency of HLA-B40 was increased (P value – 0.033, odds ratio [OR] with 95% confidence interval-2.44, [1.09, 5.48]). Similarly, the frequency of HLA-B15 and HLA-B13 were increased in PSA (P value – 0.034, 0.020 with OR – 4.09, 6.33, respectively). The presence of HLA-B27 allele favored axial ± peripheral disease while its absence favored peripheral disease (P value– 0.019). HLA-B27+ve participants had more active disease compared to HLA-B27-ve and HLA-B40+ve cases (P < 0.01 and 0.013, respectively).Conclusion: The utility of HLA-B alleles other than HLA-B27 is limited in SpA patients' management. To find their use in diagnosis, prognosis and treatment need further studies.xs