Association of HLA-B51/5 in Patients of Behcet's Disease Referred to a Tertiary Care Hospital in Pakistan.

Objective: To determine the association of HLA-B51/5 in patients of Behcet's disease (BD) in local symptomatic patients.

Study design:  A cross-sectional study. Place and Duration of the Study: Department of Immunology, Armed Forces Institute of Pathology, Rawalpindi, Pakistan, from August 2020 to July 2023.

Methodology: Blood samples of 100 study participants, including 50 symptomatic patients of BD and 50 disease-free individuals (healthy controls), were taken. DNA was extracted and amplified using sequence-specific primers. Electrophoresis was conducted on 2% agarose gel to separate the DNA. The presence of HLA-B51/5 alleles was determined by analysing the unique band patterns visible on the gel under the ultraviolet light. Descriptive statistics were shown as mean ± SD. Chi-square test was employed to find any significant association between HLA-B51/5 and the disease group and its severity sub-groups. A p-value of less than 0.05 was deemed significant.

Results: The majority of participants, 73 (73%), were females and 27 (27%) were males, with a mean age of 26.84 ± 5.31 years. HLA-B51/5 was positive in 33 of the BD patients (66.0%, <0.001) and 4 of the healthy controls (8.0%). There was no significant difference in HLA-B51 among mild, moderate, and severe BD sub-groups.

Conclusion: HLA-B51/5 is strongly associated with BD in local population and serves as a useful tool for diagnosis of BD. However, it is not associated with the disease severity.

Key words: Agarose gel, Behcet's disease, Electrophoresis, HLA-B51/5 allele, ICBD criteria.