Iranian Journal of Medical Sciences

Document Type: Original Article(s)


1 Department of Microbiology, Al-Nahrain College of Medicine, Al-Nahrain University, Baghdad, Iraq

2 Microbiologist, College of Pharmacy, Al Mustansiyria University, Baghdad, Iraq

3 Department of Microbiology, College of Medicine, Al Mustansiyria University, Baghdad, Iraq


Background: Pulmonary tuberculosis (PT) is one of the endemic diseases in Iraq, and among the suggested predisposing factors are alleles of the human leukocyte antigen (HLA) system. We sought to investigate the association between HLA-class I (A and B) and -class II (DR and DQ) alleles in a sample of PT Iraqi patients.Methods: lymphocytes of 105 PT patients and 40 controls were phenotyped for HLA-A, -B, -DR, and -DQ alleles by means of the microlymphocytotoxicity test using a panel of monoclonal antisera. Results: HLA frequencies of B18 (16.2 vs. 2.5%; OD=7.53) and DR1 (51.4 vs. 10.0%; OD=9.53) alleles were significantly increased in the patients as compared with the controls, while B5 (6.7 vs. 25.0%), DR8 (1.9 vs. 17.5%), and DQ3 (11.4 vs. 45.0%) alleles were significantly decreased. However, a significant corrected level was maintained for only DR1, DR8, and DQ3 alleles (Pc=1.9×10-5, 0.02 and 1.0×10-4, respectively).Conclusion: The results confirm the predisposing and protecting roles of HLA alleles in PT.