Despite being one of the first antitubercular agents identified, isoniazid (INH) is still the most prescribed drug for prophylaxis and tuberculosis (TB) treatment and, together with rifampicin, the pillars of current chemotherapy. A high percentage of isoniazid resistance is linked to mutations in the pro-drug activating enzyme KatG, so the discovery of direct inhibitors (DI) of the enoyl-ACP reductase (InhA) has been pursued by many groups leading to the identification of different enzyme inhibitors, active against Mycobacterium tuberculosis (Mtb), but with poor physicochemical properties to be considered as preclinical candidates. Here, we present a series of InhA DI active against multidrug (MDR) and extensively (XDR) drug-resistant clinical isolates as well as in TB murine models when orally dosed that can be a promising foundation for a future treatment.
View Article and Find Full Text PDFObjectives: We analysed the ability of Mycobacterium tuberculosis clinical isolates to penetrate and grow inside murine macrophages as a surrogate of fitness.
Methods: Thirty-five drug-resistant and 10 drug-susceptible M. tuberculosis isolates were studied in a murine macrophage model from the J774.
Objectives: To determine the proportion and type of mutations in Mycobacterium tuberculosis isolates resistant to streptomycin, and their relationship with the level of resistance and with the epidemiological molecular pattern of the isolates.
Methods: Sixty-nine streptomycin-resistant isolates from a M. tuberculosis strain collection (1995-2005) from Barcelona were studied.
The aim of this study was to analyze the factors associated with conventional contact tracing (CCT) and molecular epidemiology (ME) methods in assessing tuberculosis (TB) transmission, comparing the populations studied and the epidemiological links established by both methods. Data were obtained from TB case and CCT registries, and ME was performed using IS6110-based restriction fragment length polymorphism (RFLP) analysis and mycobacterial interspersed repetitive unit 12 (MIRU12) typing as a secondary typing method. During two years (2003 and 2004), 892 cases of TB were reported, of which 687 (77%) were confirmed by culture.
View Article and Find Full Text PDFMycobacterium tuberculosis strains that are resistant to an increasing number of second-line drugs used to treat multidrug-resistant tuberculosis (MDR TB) are becoming a threat to public health worldwide. We surveyed the Network of Supranational Reference Laboratories for M. tuberculosis isolates that were resistant to second-line anti-TB drugs during 2000-2004.
View Article and Find Full Text PDFJ Clin Microbiol
June 2007
In this multicenter study, the reliability of two nonradiometric, fully automated systems, the MB/BacT and BACTEC MGIT 960 systems, for testing the susceptibilities of 82 Mycobacterium tuberculosis strains to isoniazid, rifampin, ethambutol, and streptomycin was evaluated in comparison with the radiometric BACTEC 460TB system. The arbitration of discrepant results was done by the reanalysis of the strain, the determination of the MIC, and the molecular characterization of some resistance determinants. The overall level of agreement with BACTEC 460TB results was 96% with the MB/BacT test and 97.
View Article and Find Full Text PDFIntroduction: This study assesses the epidemiological and clinical data, as well as therapy and evolution in a recent series of patients with tuberculous meningitis (MT). A comparative study was conducted between adult MT patients with and without concurrent human immunodeficiency virus (HIV) infection.
Methods: From 1987 to 2000, 75 episodes of MT were diagnosed, 39 of them (52%) in patients with prior HIV infection.
We report on four cases of infection by the recently described species Mycobacterium parascrofulaceum. In two cases the mycobacterium was isolated from AIDS patients, while in the others it was responsible for pulmonary disease in elderly men. Our findings suggest that M.
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