Background: Pulmonary tuberculosis (PTB) develops by a
complex combination of environmental factors with genetic
susceptibility. In this context, an association between human leukocyte
antigens (HLAs) and tuberculosis has been examined in several
populations, but results have been controversial.
measurements: A prospective evaluation of class II HLA genotypes
was completed by the polymerase chain reaction (PCR) sequence-specific
primer technique and PCR sequence-specific oligonucleotide
hybridization in a Mexican population.
study was conducted at the Clinical Service of Tuberculosis and the
Department of Immunology, National Institute of Respiratory Diseases,
México City, México.
groups were examined: 95 healthy subjects; 50 nonimmunosuppressed PTB
patients; 15 HIV-infected patients (stage IVc in the Centers for
Disease Control and Prevention [CDC] classification system for
AIDS) with PTB; and 37 HIV-infected patients in the asymptomatic
stage (CDC stage II).
frequencies of alleles DQA1*0101 (odds ratio [OR], 6.18;
95% confidence interval [CI], 2.38 to 16.08), DQB1*0501 (OR,
6.16; 95% CI, 2.44 to 17.71), and DRB1*1501 (OR, 7.92; 95% CI,
2.71 to 23.14) were significantly increased in nonimmunosuppressed
patients with PTB when compared with healthy subjects. By contrast,
frequencies of allele DQB1*0402 and antigens DR4 and DR8
were significantly decreased in patients with PTB. Additionally, a
significantly higher frequency of the DRB1*1101 allele was found in
HIV-positive subjects (OR, 6.67; 95% CI, 2.13 to 20.83).
Conclusion: The genetic influence associated with the HLA
system appears to have an important role in the development of PTB,
although this susceptibility may not be relevant in patients with
severe immunodeficiency diseases such as
Abbreviations: CI = confidence
interval; CDC = Centers for Disease Control and Prevention;
EDTA =ethylenediaminetetraacetic acid; HLA = human leukocyte
antigen; MHC = major histocompatibility complex; OR = odds ratio;
PCR = polymerase chain reaction; PTB = pulmonary tuberculosis;
SSPE = sodium chloride, sodium phosphate, and EDTA;
TB = tuberculosis