Liquid vs Solid Culture Medium to Evaluate Proportion and Time to Change in Management of Suspects of Tuberculosis-A Pragmatic Randomized Trial in Secondary and Tertiary Health Care Units in Brazil.

Background: The use of liquid medium (MGIT960) for tuberculosis (TB) diagnosis was recommended by WHO in 2007. However, there has been no evaluation of its effectiveness on clinically important outcomes.

Methods And Findings: A pragmatic trial was carried out in a tertiary hospital and a secondary health care unit in Rio de Janeiro City, Brazil.

Mycobacterium tuberculosis isolates from Rio de Janeiro reveal unusually low correlation between pyrazinamide resistance and mutations in the pncA gene.

It has been widely accepted, that pyrazinamide (PZA) resistance in Mycobacterium tuberculosis is correlated with mutations in the pncA gene. But since years researchers have been puzzled by the fact that up to 30% of PZA resistant strains do not show any correlation between PZA resistance and mutations in the pncA gene, and thus may vary with geographic area. The objective of the study was to investigate the correlation between PZA susceptibility and mutations in pncA gene in M.

Correlation between resistance to pyrazinamide and resistance to other antituberculosis drugs in Mycobacterium tuberculosis strains isolated at a referral hospital.

The correlation between resistance to pyrazinamide (PZA) and resistance to other first-line antituberculosis drugs was investigated in 395 Mycobacterium tuberculosis strains isolated from clinical specimens, representing 14% of the overall number of M. tuberculosis isolates obtained between 2003 and 2008 at the laboratory of a referral university hospital for tuberculosis. A high correlation was found between resistance to PZA and multidrug resistance, as well as between PZA resistance and resistance to rifampin, isoniazid, and ethambutol (p < 0.

Comparative evaluation under routine conditions of the nitrate reduction assay, the proportion assay and the MGIT 960 assay for drug susceptibility testing of clinical isolates of Mycobacterium tuberculosis.

The performance of the nitrate reductase assay (NRA) was compared with the proportion method (PM) on Lowenstein-Jensen medium and the BACTEC MGIT960 assay under routine conditions using 160 clinical isolates of Mycobacterium tuberculosis with a high proportion of resistant strains. The mean time to obtain results was 8.8 days and the overall agreements between NRA and PM and NRA and M960 were 95% and 94%, respectively.

Clinical evaluation of the microscopic observation drug susceptibility assay for detection of Mycobacterium tuberculosis resistance to isoniazid or rifampin.

This prospective study evaluated the performance of the microscopic observation drug susceptibility (MODS) assay for the direct detection of Mycobacterium tuberculosis drug resistance. MODS assay sensitivity, specificity, and positive and negative predictive values were 96.7% (95% confidence interval [95% CI], 92.

Clinical evaluation of the microscopic-observation drug-susceptibility assay for detection of tuberculosis.

Background: There is an urgent need for low-cost methods for rapid, accurate detection of Mycobacterium tuberculosis in clinical specimens. The microscopic-observation drug-susceptibility (MODS) assay is a relatively low-cost and simple liquid culture method that has been proposed for use in resource-limited environments.

Methods: This prospective study evaluated the performance of the MODS assay for detection of M.