Beijing genotype of Mycobacterium tuberculosis is less associated with drug resistance in south China

Abstract Mycobacterium tuberculosis Beijing genotype strains are widespread globally. However, there has been no systematic study on the associations between Beijing genotype and the characteristics of drug resistance. In this study, we collected 359 M. tuberculosis isolates from south China and investigated their background information, genotype diversity and drug resistance. The results revealed that 66.0% (237/359) of strains were categorized as Beijing genotype. There was no statistical difference between Beijing and non-Beijing genotype strains in terms of sex, age, residence place and treatment history. Drug resistance testing showed that 34.8% (125/359) of isolates were resistant to at least one of the seven drugs tested. The proportions of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis were 17.0% and 1.4%, respectively. Previously treated patients presented a significantly higher risk of developing drug resistance than new cases. Although the prevalence of drug resistance was observed more frequently in Beijing genotype than in non-Beijing genotype strains, there was no significant difference between these two genotypes. Even in retreated patients, the association of Beijing genotype with drug resistance was not significant. This study provided insight into genotype diversity and demonstrated the characteristics of drug resistance in Beijing genotype strains, which will be useful in generating efficient tuberculosis prevention and control strategies in China.