Genetic Diversity and Molecular Epidemiology of Mycobacterium tuberculosis in Roraima State, Brazil.

National border areas are special places for the spread of Mycobacterium tuberculosis (MTB). These regions concentrate vulnerable populations and constant population movements. Understanding the dynamics of the transmission of MTB is fundamental to propose control measures and to monitor drug resistance. We conducted a population-based prospective study of tuberculosis (TB) to evaluate molecular characteristics of MTB isolates circulating in Roraima, a state on the border of Venezuela and Guyana. Eighty isolates were genotyped by IS6110-RFLP (restriction fragment length polymorphism), spoligotyping, and 24-locus mycobacterial interspersed repetitive unit-variable number of repeats tandem (MIRU-VNTR). Drug susceptibility tests were performed by using the proportion method and GeneXpert® MTB/RIF (Cepheid, Sunnyvale, CA). Isolates showing a phenotypic resistance profile were submitted to polymerase chain reaction (PCR) and sequencing. Spoligotyping showed 40 distinct patterns with a high prevalence of Latin-American and Mediterranean (LAM), Haarlem (H), and the "ill-defined" T clades. Mycobacterial interspersed repetitive unit -VNTR and IS6110-RFLP showed clustering rates of 21.3% and 30%, respectively. Drug resistance was detected in 11 (15.1%) isolates, and all were found to have primary resistance; among these, six (8.2%) isolates were streptomycin mono-resistant, four (5.4%) isoniazid mono-resistant, and one (1.3%) multidrug resistant. This is the first study on the molecular epidemiology and drug resistance profile of MTB from Roraima. Herein, we describe high diversity of genetic profiles circulating in this region that may be driven by the introduction of new strain types because of large population flow in this region. In summary, our results showed that analyses of these circulating strains can contribute to a better understanding of TB epidemiology in the northern Brazilian border and be useful to establish public health policies on TB prevention.

Risk factors for KPC-producing Klebsiella pneumoniae: watch out for surgery.

This study describes the molecular characteristics and risk factors associated with carbapenem-resistant Klebsiella pneumoniae strains. Risk factors associated with KPC-producing K. pneumoniae strains were investigated in this case-control study from May 2011 to May 2013. Bacterial identification was performed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined by broth microdilution. Carbapenemase production was assessed by both modified Hodge test (MHT) and ertapenem hydrolysis using MALDI-TOF MS. The presence of ß-lactamase-encoding genes was evaluated by PCR and DNA sequencing. Alterations in genes encoding K. pneumoniae outer membrane proteins were analysed by PCR and DNA sequencing as well as SDS-PAGE. Genetic relatedness among strains was determined by pulsed-field gel electrophoresis. This study included 94 patients. Longer hospitalisation, mechanical ventilation, catheters, and previous surgery were associated with KPC-producing K. pneumoniae. Sixty-eight strains showed resistance to carbapenems. Carbapenemase production was detected by MHT in 67 K. pneumoniae strains and by MALDI-TOF MS in 57. The presence of the blaKPC-2 gene was identified in 57 strains. The blaKPC-2 gene was not found in 11 carbapenem-resistant K. pneumoniae; instead, the blaCTX-M-1-like, blaCTX-M-2-like, blaCTX-M-8 like, blaCTX-M-14-like and blaSHV- like genes associated with OmpK35 and OmpK36 alterations were observed. Thirty-three KPC-producing K. pneumoniae strains were clonally related, and patients infected with these strains had a higher mortality rate (78.78 %). Our results show that KPC-producing K. pneumoniae was associated with several healthcare-related risk factors, including recent surgery.

Chronic symptoms and pulmonary dysfunction in post-tuberculosis Brazilian patients

ABSTRACTBACKGROUND: Questionnaire and spirometry were applied to post-tuberculosis indigenous and non-indigenous individuals from Dourados, Brazil, to investigate the prevalence of chronic respiratory symptoms and pulmonary dysfunction.METHODS:This was a cross-sectional study in cured tuberculosis individuals as reported in the National System on Reportable Diseases (SINAN) from 2002 to 2012.RESULTS:One hundred and twenty individuals were included in the study and the prevalence of chronic respiratory symptoms was 45% (95% CI, 34-59%). Respiratory symptoms included cough (28%), sputum (23%), wheezing (22%) and dyspnea (8%). These symptoms were associated with alcoholism, AOR: 3.1 (1.2-8.4); less than 4 years of schooling, AOR: 5.0 (1.4-17.7); and previous pulmonary diseases, AOR: 5.4 (1.7-17.3). Forty-one percent (95% CI, 29-56) had pulmonary disorders, of which the most prevalent were obstructive disorders (49%), followed by obstructive disorder with reduced forced vital capacity disorders (46%) and restrictive disorders (5%). The lifestyle difference could not explain differences in chronic symptoms and/or the prevalence of pulmonary dysfunction.CONCLUSION:The high prevalence of chronic respiratory symptoms and pulmonary dysfunction in post-tuberculosis patients indicates a need for further interventions to reduce social vulnerability of patients successfully treated for tuberculosis.

Chronic symptoms and pulmonary dysfunction in post-tuberculosis Brazilian patients.

BACKGROUND: Questionnaire and spirometry were applied to post-tuberculosis indigenous and non-indigenous individuals from Dourados, Brazil, to investigate the prevalence of chronic respiratory symptoms and pulmonary dysfunction. METHODS: This was a cross-sectional study in cured tuberculosis individuals as reported in the National System on Reportable Diseases (SINAN) from 2002 to 2012. RESULTS: One hundred and twenty individuals were included in the study and the prevalence of chronic respiratory symptoms was 45% (95% CI, 34-59%). Respiratory symptoms included cough (28%), sputum (23%), wheezing (22%) and dyspnea (8%). These symptoms were associated with alcoholism, AOR: 3.1 (1.2-8.4); less than 4 years of schooling, AOR: 5.0 (1.4-17.7); and previous pulmonary diseases, AOR: 5.4 (1.7-17.3). Forty-one percent (95% CI, 29-56) had pulmonary disorders, of which the most prevalent were obstructive disorders (49%), followed by obstructive disorder with reduced forced vital capacity disorders (46%) and restrictive disorders (5%). The lifestyle difference could not explain differences in chronic symptoms and/or the prevalence of pulmonary dysfunction. CONCLUSION: The high prevalence of chronic respiratory symptoms and pulmonary dysfunction in post-tuberculosis patients indicates a need for further interventions to reduce social vulnerability of patients successfully treated for tuberculosis.

Impact of latent infection treatment in indigenous populations.

The aims of the present study were to identify risk factors associated with latent tuberculosis (TB), examine the development of active disease among contacts, and assess the effectiveness of treating latent infection in indigenous Brazilians from January 2006 to December 2011. This was a retrospective study consisting of 1,371 tuberculosis contacts, 392 of whom underwent treatment for latent infection. Morbidity-from-TB data were obtained from the Information System for Disease Notification (SINAN) database, and the contacts' data were collected from the clinical records using forms employed by Special Department of Indigenous Health (SESAI) multidisciplinary teams, according to SESAI's instructions. The variables that were associated with latent infection among the contacts were age (odds ratio [OR]: 1.03; 95% confidence interval [CI]: 1.02-1.04) and close contact with a smear-positive index case (OR: 2.26, 95% CI: 1.59-3.22). The variables associated with the development of active TB among the contacts were a tuberculin skin test (TST) ≥10 mm (relative risk [RR]: 1.12, 95% CI: 1.07-1.17), age (RR: 1.01, 95% CI: 1.00-1.03), and treatment of latent infection (RR: 0.03, 95% CI: 0.01-0.27). The estimated number of latent infection treatments needed to prevent one case of active TB among the contacts was 51 treatments (95% CI: 33-182). In contacts with TST ≥10 mm, 10 (95% CI: 6-19) latent infection treatments were necessary to prevent one case of active TB. Age and close contact with a smear-positive index case were associated with latent TB. Screening with TST is a high priority among individuals contacting smear-positive index cases. Age and TST are associated with the development of active TB among contacts, and treatment of latent infection is an effective measure to control TB in indigenous communities.

Sugar cane manufacturing is associated with tuberculosis in an indigenous population in Brazil.

BACKGROUND: Tuberculosis (TB) remains one of the leading causes of morbidity and mortality among indigenous peoples in Brazil, and identifying the risk factors for TB in this population secondary to specific epidemiological conditions is essential for recommending interventions aimed at disease control. METHODS: This case-control study was conducted with an indigenous population between June 2009 and August 2011 in Dourados, Brazil. Tuberculosis cases reported to the national disease surveillance programme were paired with two control cases matched by age and geographic location. RESULTS: There were 63 cases included in this study, and the annual incidence of TB in the indigenous communities examined was 222 (95% CI, 148-321) per 100 000 inhabitants. The multivariate analysis demonstrated that the variables associated with TB infection included male gender (OR 2.6; 95% CI 1.3-5.3), not owning a home (OR 3.4; 95% CI 1.2-10.1), illiteracy (OR 2.4; 95% CI 1.1-5.0), TB contact (OR 2.4; 95% CI 1.2-4.8) and work performed in a sugar cane factory (OR 6.8; 95% CI 1.2-36.9). CONCLUSION: There is a potential relationship between exposure to sugar cane manufacturing processes and tuberculosis infection among indigenous populations.