Clinical and genotypic characteristics of extensively drug-resistant and multidrug-resistant tuberculosis

The aims of this study were to compare the clinical features of patients with extensively drug-resistant tuberculosis (XDRTB) and multidrug-resistant tuberculosis (MDRTB) and the genotypic characteristics of these Mycobacterium tuberculosis isolates. A total of 90 non-HIV-infected patients having MDRTB (n = 80, not including XDRTB, 88.9%) and XDRTB (n = 10, 11.1%) were identified from 2000 to 2007. Genotypes of the 39 available isolates were evaluated by spoligotyping and the 24-locus mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) scheme. Patients with XDRTB were more likely to have previous history of TB and cavitary lung lesions than patients with MDRTB (P < 0.05). Among the 39 isolates for spoligotyping analysis, the Beijing genotype was the most common (n = 21, 53.8%). Four (44.4%) isolates of XDRTB and 17 (56.7%) isolates of MDRTB belonged to Beijing family genotypes. There was no significant difference in the anti-tuberculosis drug resistance rates between Beijing and non-Beijing genotype isolates or in the clinical features of infected patients. In conclusion, significant differences in clinical manifestations existed among patients with XDRTB and MDRTB. The clinical features of patients infected with the Beijing genotype and the drug resistance profile of the Beijing genotype isolates were similar to those for the non-Beijing family genotype.