HLA‐B27 prevalence in axial spondyloarthritis patients and in blood donors in a Lebanese population: Results from a nationwide study

Abstract

Aim:To calculate the prevalence of human leukocyte antigen (HLA)-B27 in axial spondyloarthritis patients (axSpA) compared to blood donors (BD) in Lebanon, to identify the clinical and radiological findings associated with HLA-B27 and to estimate the proportion of patients fulfilling the clinical arm of the Assessment of the Spondyloarthritis International Association (ASAS) criteria. Method:Consecutive Lebanese adult axSpA patients fulfilling the ASAS classification criteria were included from 12 rheumatology clinics across Lebanon. BD served as controls. A binary logistic regression was used to study the association between HLA-B27 and the disease features.Results: A total of 247 individuals were included (141 axSpA patients and 106 BD).The prevalence of HLA-B27 was 3.8% in BD and 41.1% in axSpA. Overall, 39.7% of the axSpA patients fulfilled the clinical arm of the ASAS classification criteria.Sensitivity of HLA-B27 for axSpA was 41.1%, specificity was 96.2%, positive predictive value was 93.6%, and negative predictive value was 55.13%. Positive likelihood ratio (LR) was 10.9 and negative LR was 1.63. We found a positive association of HLA-B27 with family history of SpA and psoriasis. Conclusion:Our study confirmed a low prevalence of HLA-B27 in axSpA patients and BD in this Lebanese population, However, we found a high specificity and positive LR, as well as the same number of axSpA patients fulfilling the clinical arm of the ASAS criteria as in European studies. HLA-B27 is therefore valuable for identification of axSpA in Lebanese patients despite the overall low prevalence in this population.Our results may guide future evaluations the role of HLA-B27 in planning local referral strategies.

Prevalence of HLA-B27 in Turkish Patients with Ankylosing Spondylitis and Non-radiographic Axial Spondyloarthritis

“…In a recent study, Ziade et al calculated the prevalence HLA-B27 in axSpA in Lebanon. 18 With the agreement of our findings, they found that the low prevalence of HLA-B27 (41.1%) in axSpA.…”

Comparison of Clinical Features in HLA-B27 Positive and Negative Patients With Axial Spondyloarthritis: Results From a Cohort of 4,131 Patients

“…Furthermore, the distribution of HLA-B27 population is various. Higher rates of HLA-B27 were found in ax-SpA patients of North America and Western Europe (80-95%) (8) than in Japan and Arab countries (41-84%) (9,10). Meanwhile, the data for China is limited.…”

Younger age of onset and uveitis associated with HLA-B27 and delayed diagnosis in Thai patients with axial spondyloarthritis

“…Conversely, arthritis, enthesitis, and relevant family history had no association with HLA-B27, which differed from the Chung et al study 8 . These characteristics were not found to significantly associate with HLA-B27 in studies conducted in Turkey 32 and Lebanon 28 . This may be due to different duration of disease, ethnicity, and/or genetics, including HLA-B27 subtype.…”

“…The prevalence in our study was comparable to previously reported rates from countries that have comparable HLA-B27 frequency in general population (2–9%) 6 , such as 62% among French combined nr-axSpA and r-axSpA patients 8 , 72.3% among Chinese nr-axSpA patients 27 , and 82% among German AS patients 24 . In contrast, the prevalence among axSpA in the Middle East and among Arab AS patients varies widely from 26% in Lebanon to 91% in Turkey 5 , 28 , and the HLA-B27 frequency in general population in these countries ranges from 3 to 14% 6 . Moreover, there was a higher frequency of HLA-B27 among r-axSpA than among nr-axSpA 24 , and AS had a higher prevalence of HLA-B27 than any other SpA diseases 6 , which is consistent with the present study.…”