Background and Aims

Sarcoidosis and tuberculosis have several similar clinical and pathogenetic characteristics, what makes some researchers consider a common pathogenesis for these diseases. HLA-genotypes are known as a genetic predisposition factor for many diseases and are studied for sarcoidosis and tuberculosis patients. However there is no comparative study of genetic predisposition for sarcoidosis or tuberculosis development.

The aim of this study was to analyze the relationship between HLA genotypes and the development of sarcoidosis and tuberculosis.

Methods

Original (n=19) and review articles (n=14) published in various online databases from 1960 to 2019 were studied. The papers were selected according to key words: sarcoidosis, tuberculosis, HLA-genotype, genetic predisposition.

Results

The study results showed opposite effects of the HLA genotypes associated with a predisposition to the development of sarcoidosis or tuberculosis. It was revealed, the genotypes predisposing to the development of sarcoidosis (HLA-DRB1*03/07/15) have protective properties against the development of tuberculosis. Moreover, genotypes causing its development (HLA-DRB1*04) have a protective effect on the development of sarcoidosis. Some of these results might be explained by the weak affinity of MHC molecules for mycobacterial antigens in patients with HLA-DRB1*04 genotype and the strong affinity of MHC proteins for bacterial antigens in individuals with HLA-DRB1*03: 01 genotype

Conclusions

The HLA system may determine the development of the immune response in contact with mycobacteria. It was shown that HLA-DRB1*04 genotype predispose to tuberculosis development, while the HLA-DRB1*03/07/15 genotypes to sarcoidosis. Determining the HLA genotypes may result in assessing a risk degree for developing tuberculosis or sarcoidosis in the foci of mycobacterial infection.