Genetic diversity of the Mycobacterium tuberculosis Beijing family in Brazil and Mozambique and relation with infectivity and induction of necrosis in THP-1 cells.

Introduction: The success of the Mycobacterium tuberculosis Beijing (MtbB) lineage in different geographical regions has been attributed to high transmission, increased virulence, drug resistance and rapid adaptation to the host. In some countries of secondary MtbB dispersion like South Africa and Peru, rising prevalence of the Beijing strains is registered. However, in neighboring countries to affected regions such as Mozambique and Brazil, respectively, the prevalence of these strains is still low and this could be due to biological particularities of the circulating MtbB strains and/or differentiated host susceptibility.

Bottlenecks and recommendations for the incorporation of new technologies in the tuberculosis laboratory network in Brazil.

The World Health Organization (WHO) has recently recommended new technologies for the diagnosis of tuberculosis. The WHO recommendations include the development of a strategic plan for bringing the network up to grade; investment in supervision and quality control; and implementation of a system of laboratory environmental management. Without those measures having been taken, no new technology can be effectively incorporated.

Susceptibility of Mycobacterium tuberculosis to first-line antimycobacterial agents in a Brazilian hospital: assessing the utility of the tetrazolium (MTT) microplate assay.

We conducted a cross-sectional, hospital-based study between January 2006-March 2008 to estimate the resistance of Mycobacterium tuberculosis to first-line drugs in patients with tuberculosis at a Brazilian hospital. We evaluated the performance of the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide] (MTT) microplate assay compared with the Bactec-MGIT 960 system for mycobacteria testing. The prevalence of resistance in M.

Cord factor detection and macroscopic evaluation of mycobacterial colonies: an efficient combined screening test for the presumptive identification of Mycobacterium tuberculosis complex on solid media.

Objective: The rapid differentiation between Mycobacterium tuberculosis and nontuberculous mycobacteria is fundamental for patients co-infected with tuberculosis and HIV. To that end, we use two methods in our laboratory: detection of cord factor and PCR-restriction enzyme analysis (PRA). The objective of this study was to evaluate the accuracy of a screening test on solid medium as a rapid method for the presumptive identification of M.

III Brazilian Thoracic Association Guidelines on tuberculosis.

New scientific articles about tuberculosis (TB) are published daily worldwide. However, it is difficult for health care workers, overloaded with work, to stay abreast of the latest research findings and to discern which information can and should be used in their daily practice on assisting TB patients. The purpose of the III Brazilian Thoracic Association (BTA) Guidelines on TB is to critically review the most recent national and international scientific information on TB, presenting an updated text with the most current and useful tools against TB to health care workers in our country.

Rapid detection of resistant tuberculosis by nitrate reductase assay performed in three settings in Brazil.

Objectives: To evaluate nitrate reductase assay (NRA) efficacy for streptomycin, isoniazid, rifampicin and ethambutol susceptibility testing of Mycobacterium tuberculosis strains.

Methods: Results were generated by three laboratories: the Instituto Adolfo Lutz (IAL) Mycobacteria Reference Laboratory and two IAL Regional Laboratories in Santo André and Sorocaba, São Paulo State, Brazil. One hundred and twenty M.

Maintenance of Mycobacterium tuberculosis on glass beads.

The intent of this study was to estimate the shelf life of Mycobacterium tuberculosis strains, and to observe the loss of viability in some of them from year to year. From 2000 to 2004, 10,015 cultures of M. tuberculosis were preserved by freezing on glass beads at -70 degrees C.

Identification of non-tuberculous mycobacteria from the Central Public Health Laboratory from Mato Grosso do Sul and analysis of clinical relevance.

Non-tuberculous mycobacteria isolated at the Central Public Health Laboratory from Mato Grosso do Sul in 2003 and 2004 were identified by conventional phenotypic methods (TI) and by PCR-Restriction Enzyme Analysis (PRA) using the hsp65 gene as target (PRA-hsp65). With 15 of the 32 analysed isolates, results of both methods were concordant, being 8 Mycobacterium avium, 3 M. fortutium, 1 M.

Mycobacterium kansasii: antibiotic susceptibility and PCR-restriction analysis of clinical isolates.

Mycobacterium kansasii is the second most common cause of non-tuberculosis mycobacterial diseases in Sao Paulo, Brazil. An important component of the management of infections caused by this organism is antibiotic susceptibility testing. The objective of this study was to determine the drug susceptibility profiles and genotypes of clinical isolates of M.

Multicenter evaluation of mycobacteria identification by PCR restriction enzyme analysis in laboratories from Latin America and the Caribbean.

The identification of mycobacterial species in clinical isolates is essential for making patient care decisions. Polymerase chain reaction (PCR) restriction enzyme analysis (PRA) is a simple and rapid identification method, based on amplification of 441 bp of the hsp65 gene and restriction with BstEII and HaeIII. As a contribution to the validation of PRA, a multicenter study was performed in eight laboratories located in Argentina, Brazil, Colombia, Chile, and Guadeloupe.

Molecular characterization of Mycobacterium kansasii isolates in the State of São Paulo between 1995-1998.

Mycobacterium kansasii is the most common cause of pulmonary nontuberculous mycobacteria infection and classical identification of this pathogen needs a time consuming phenotypic tests. Polymerase chain reaction-restriction fragment length polymorphism analysis (PRA) of the gene enconding for the 65 kDa heat shock (hsp65) protein offers an easy, rapid, and inexpensive procedure to identify and subtype M. kansasii isolates.

[Distribution of PRA patterns of clinical isolates of the Mycobacterium avium complex from Spain and South America].

Mycobacterium avium complex (MAC) infections are the most frequent systemic infections associated with advanced AIDS. DNA probes for accurate identification of mycobacteria are available but are very expensive in many Latin American settings. Consequently, most Latin American diagnostic laboratories employ inaccurate and outdated tests for mycobacteria identification.