A descriptive study on isoniazid resistance-associated mutations, clustering and treatment outcomes of drug-resistant tuberculosis in a high burden country.

Purpose: To describe katG and inhA mutations, clinical characteristics, treatment outcomes and clustering of drug-resistant tuberculosis (TB) in the State of São Paulo, southeast Brazil.

Methods: Mycobacterium tuberculosis isolates from patients diagnosed with drug-resistant TB were screened for mutations in katG and inhA genes by line probe assay and Sanger sequencing, and typed by IS6110-restriction fragment-length polymorphism for clustering assessment. Clinical, epidemiological and demographic data were obtained from surveillance information systems for TB.

Identification of a predominant genotype of Mycobacterium tuberculosis in Brazilian indigenous population.

After nearly a century of vaccination and six decades of drug therapy, tuberculosis (TB) kills more people annually than any other infectious disease. Substantial challenges to disease eradication remain among vulnerable and underserved populations. The Guarani-Kaiowá people are an indigenous population in Paraguay and the Brazilian state of Mato Grosso do Sul.

Transmission of Mycobacterium tuberculosis presenting unusually high discordance between genotypic and phenotypic resistance to rifampicin in an endemic tuberculosis setting.

Background: Since the implementation of the Xpert MTB/RIF in Sao Paulo, Brazil, numerous Mycobacterium tuberculosis isolates presenting "rifampicin-resistant genotype with rifampicin-susceptible phenotype" were observed.

Objective: To evaluate the prevalence, rpoB mutations and transmission of M. tuberculosis resistant to rifampicin on Xpert MTB/RIF but susceptible on BACTEC MGIT system, in Sao Paulo state.

Transmission and prevalence of drug-resistant tuberculosis in a Brazilian setting under a directly observed therapy short-course strategy.

Introduction: We aimed to estimate the prevalence and transmission of drug-resistant tuberculosis in a high-burden Brazilian setting under directly observed therapy short-course strategy.

Methods: Isolates of culture-confirmed pulmonary tuberculosis patients from Guarulhos, Brazil, diagnosed in October 2007-2011 were subjected to drug susceptibility and IS6110-restriction fragment length polymorphism testing.

Results: The overall resistance prevalence was 11.

Migration and tuberculosis transmission in a middle-income country: a cross-sectional study in a central area of São Paulo, Brazil.

Background: Little is known about the impact of growing migration on the pattern of tuberculosis (TB) transmission in middle-income countries. We estimated TB recent transmission and its associated factors and investigated the presence of cross-transmission between South American migrants and Brazilians.

Methods: We studied a convenient sample of cases of people with pulmonary TB in a central area of São Paulo, Brazil, diagnosed between 2013 and 2014.