Case Report
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 21, 2022; 10(3): 992-999
Published online Jan 21, 2022. doi: 10.12998/wjcc.v10.i3.992
Occurrence of human leukocyte antigen B51-related ankylosing spondylitis in a family: Two case reports
Mie Jin Lim, Eul Noh, Ro-Woon Lee, Kyong-Hee Jung, Won Park
Mie Jin Lim, Eul Noh, Kyong-Hee Jung, Won Park, Rheumatology/Internal Medicine, Inha University, Incheon 22332, South Korea
Ro-Woon Lee, Radiology, Inha University, Incheon 22332, South Korea
Author contributions: Lim MJ and Noh E were the attending doctors; Noh E, Lim MJ, and Jung KH reviewed the literature; Lim MJ and Lee RW contributed to manuscript drafting; Lee RW interpreted the radiologic imaging; Lim MJ and Park W were responsible for the revision of the manuscript; and all authors issued final approval for the version to be submitted.
Informed consent statement: This study was approved by the Institutional Review Board of Inha University Hospital (Incheon, Korea; IRB 2020-03-003), and written informed consent was obtained from all participants.
Conflict-of-interest statement: The authors have no potential conflicts of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Won Park, MD, PhD, Doctor, Professor, Rheumatology/Internal Medicine, Inha University, Inhangro 27, JungGu, Incheon 22332, South Korea. parkwon@inha.ac.kr
Received: February 26, 2021
Peer-review started: February 26, 2021
First decision: October 16, 2021
Revised: October 27, 2021
Accepted: December 25, 2021
Article in press: December 25, 2021
Published online: January 21, 2022
Processing time: 323 Days and 1.8 Hours
Abstract
BACKGROUND

Ankylosing spondylitis (AS) is strongly associated with the human leukocyte antigen (HLA) B27 haplotype. In regions where conventional polymerase chain reaction for HLA typing is available for antigens such as HLA B27 or HLA B51, it is common to perform the HLA B27 test for evaluation of AS. While HLA B27-associated clustered occurrences of AS have been reported in families, we report the first case series of HLA B51-related occurrences of AS in a family.

CASE SUMMARY

A father and his daughters were diagnosed with AS and did not have the HLA B27 haplotype. Although they were positive for HLA B51, they exhibited no signs of Behçet’s disease (BD). Of the five daughters, one had AS, and three, including the daughter with AS, were positive for HLA B51. The two daughters with the HLA B51 haplotype (excluding the daughter with AS) exhibited bilateral grade 1 sacroiliitis, whereas the daughters without the HLA B51 haplotype did not have sacroiliitis. Thus, this Korean family exhibited a strong association with the HLA B51 haplotype and clinical sacroiliitis, irrespective of the symptoms of BD.

CONCLUSION

It is advisable to check for HLA B51 positivity in patients with AS/spondyloarthropathy who test negative for HLA B27.

Keywords: Ankylosing spondylitis; Spondyloarthropathy; Human leukocyte antigen B51; Human leukocyte antigen B27; Sacroiliitis; Case report

Core Tip: Ankylosing spondylitis (AS) is strongly associated with human leukocyte antigen (HLA) B27. In certain regions, the testing of HLA genotyping, such as HLA B27 or HLA B51, is an available medical service. Here, we report the first case series of HLA B51-related inheritance of AS in a family. No one in this family tested positive for HLA B27, and additional testing for HLA B51 revealed that family members with HLA B51 haplotype had either AS or clinical sacroiliitis without symptoms compatible with Behçet’s disease. Thus, it is advisable to perform HLA B51 testing as a genetic marker for HLA B27 negative AS/spondyloarthropathy.