Correlation of HLA B27 subtypes with clinical features of ankylosing spondylitis

Authors


Dr Rohini Samant, Department of Rheumatology, P. D. Hinduja National Hospital and Medical Research Centre, Veer Savarkar marg, Mahim, Mumbai-400016, India. Email: drrohinisamant@gmail.com

Abstract

Aim:  The aim of the present study was to identify the B*27 subtypes associated with ankylosing spondylitis (AS) in our population and correlate them with clinical features of AS.

Method:  Whole blood samples were collected from 81 HLA-B27 positive AS patients and 29 controls (asymptomatic healthy unrelated individuals) positive for HLA-B27. Clinical details of the patients were recorded which included history of inflammatory back pain, sacroiliitis, spine involvement, enthesitis, peripheral arthritis and uveitis. HLA-B27 subtypes were detected using commercially available techniques. Fisher’s exact test was used for statistical analysis.

Results:  The subtypes observed in AS patients were B*2705 (67.9%, 55/81), B*2704 (28.4%, 23/81), B*2707 (2/81) and B*2702 (1/81). Subtypes in the controls were B*2705 (62.07%, 18/29), B*2707 (27.59%, 8/29) and B*2704 (10.34%, 3/29). Uveitis was observed more in B*2704-positive AS patients (34.78%, 8/23) compared to B*2705-positive AS patients (16.36%, 9/55). However, the difference was not statistically significant (P = 0.130). No major differences were found between B*2705 and B*2704 for other clinical features.

Conclusion:  B*2705 was the main subtype observed in both patient and control groups. Frequency of B*2704 was more in AS patients compared to controls. Occurrence of AS-associated uveitis was more often in B*2704-positive AS patients compared to B*2705-positive ones.

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