ISSN: 2691-5782
Authors: Abdallah HMA*, Bolad AK, El Elobied A, Babikir AM, Osman AF and EL Hussien AM
Tuberculosis (TB) is a chronic disease caused by M. tuberculosis. The World Health Organization (WHO) estimated that Mycobacterium tuberculosis infects a one third of the worlds human population and kills two million people each year. The number of active infection was 14.4million, in Sudan the indicator of 1% corresponds to an approximate incidence of 50cases of pulmonary symptoms smear-positive TB/100,000 population. We attempt to characterize the human leukocyte antigen (HLA) among Healthcare Workers (HCWs) in Khartoum State who have vaccinated with BCG and failed to show any response to the vaccine and Tuberculin Skin Test. One-hundred thirty-seven HCWs were screened by conventional methods (microscopy, TST, HIV test and Chest X-Ray), all subjects were apparently healthy and allocated according to the TST results into three groups (strong TST-positive, moderate TST-positive, and negative groups). Link regards to HLA genotypes distribution, the present study educated that alleles associated with TB-exposed group DRB1*0701, DRB1*1501, DQB1*0501 and DQB1*0301. DRB1*0701 and DQB1*0301 with high frequency among strong TST-positive group, DRB1*0701 and DQB1*0601 alleles were with high frequency among moderate TST-positive group and DRB1*0701, DRB1*1501, DQB1*0601 alleles were with high frequency among TST-negative group. Some of these alleles (DRB1*1501, DQB1*0701, DQB1*0301 were shown exclusively in TB-exposed subjects (100%). It seems that they act as susceptibility genes to TB. Moreover, DRB1*0201 and DQB1*01 and DRB1*0301 alleles were found to be associated with control group.
Keywords: HLA; TB; BCG; Tuberculin Skin Test
