In Vitro Activities of Linezolid against Clinical Isolates of Mycobacterium tuberculosis Complex Isolated in Taiwan over 10 Years

Abstract

Significant increases in the MICTuberculosis (TB) is one of the major causes of death worldwide. The global prevalence of mycobacterial infection has been estimated to be 32% (1.9 billion people), with 8 million new cases of TB diagnosed annually and an average case fatality rate of 23% (11). In the year 2003, the incidence and mortality rate of TB in Taiwan were reported at 62.38 and 5.80 per 100,000 people, respectively (2), and TB is considered a more serious public health problem in southern than in northern Taiwan.Although TB can be cured with chemotherapy, the treatment is exceedingly lengthy and results in poor patient compliance, which is a frequent cause of selection of drug-resistant and even multidrug-resistant (MDR) Mycobacterium tuberculosis complexes. If the treatment fails as a result of drug resistance, treatment with second-line drugs is necessary. In Taiwan, the overall rates of MDR M. tuberculosis among new cases and previously treated cases ranged from 1% to 3% and 15% to 46%, respectively (5). In our previous report, increases in the MIC 90 s and rates of resistance to ciprofloxacin, ofloxacin, and levofloxacin were noted in the MDR group (6). Therefore, there is an increasing need for new antimicrobial agents against MDR M. tuberculosis.

In Vitro Activity of Linezolid against Clinical Isolates of Mycobacterium tuberculosis, including Multidrug-Resistant and Extensively Drug-Resistant Strains from Beijing, China

“…The MICs for linezolid ranged from 0.125 to 0.5 mg/mL for all tested isolates. The MIC against M. tuberculosis H37Rv was 0.5 mg/mL, in accordance with previously published data (11). There were no differences in linezolid MIC 50 (MICs for 50z of the organisms) and MIC 90 values among susceptible, INH-resistant, MDR, and XDR groups.…”

Early and Extended Early Bactericidal Activity of Linezolid in Pulmonary Tuberculosis

“…Previous studies have shown that linezolid has good in vitro activity against both drug-susceptible and MDR strains of M. tuberculosis, with MIC values of 1 mg/L or lower (2,30). The clinical use of linezolid in the treatment of TB, however, is limited to five studies of patients with MDR-TB (13)(14)(15)(16)31).…”

Efficacy, safety and tolerability of linezolid for the treatment of XDR-TB: a study in China

“…A series of studies evaluated the efficacy, safety and tolerability of the linezolid containing regimes for treating MDRand XDR-TB cases. However, most were restricted mainly to case reports, a retrospective analysis and small case series [14][15][16][17][18][19][28][29][30][31]. This is a prospective, multicentre, randomised study on efficacy, safety and tolerability of linezolid for treating XDR-TB.…”

“…Studies in vitro have shown good activity of linezolid against various species of mycobacteria, including drug-resistant mycobacterial strains [12][13][14]. Recent case studies and retrospective analysis have suggested that linezolid may be effective in treating MDR-TB and XDR-TB [15][16][17][18][19][20][21][22].…”