Objective: To compare the accuracy of the amplified Mycobacterium tuberculosis direct (AMTD) test with reference methods for the laboratory diagnosis of tuberculosis in HIV-infected patients. Methods: This was a study of diagnostic accuracy comparing AMTD test results with those obtained by culture on Löwenstein-Jensen (LJ) medium and by the BACTEC Mycobacteria Growth Indicator Tube 960 (BACTEC MGIT 960) system in respiratory samples analyzed at the Bioassay and Bacteriology Laboratory of the Oswaldo Cruz Foundation Evandro Chagas Clinical Research Institute in the city of Rio de Janeiro, Brazil. Results: We analyzed respiratory samples collected from 118 patients, of whom 88 (74.4%) were male. The mean age was 36.6 ± 10.6 years. Using the AMTD test, the BACTEC MGIT 960 system, and LJ culture, we identified M. tuberculosis complex in 31.0%, 29.7%, and 27.1% of the samples, respectively. In comparison with LJ culture, the AMTD test had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.5%, 89.4%, 75.7%, and 95.0%, respectively, for LJ culture, whereas, in comparison with the BACTEC MGIT 960 system, it showed values of 88.6%, 92.4%, 83.8%, and 94.8%, respectively. Conclusions: The AMTD test showed good sensitivity and specificity in the population studied, enabling the laboratory detection of M. tuberculosis complex in paucibacillary respiratory specimens.

Keywords: Molecular diagnostic techniques; Tuberculosis; HIV; Molecular probe techniques.

This study aimed to assess drug resistance in Mycobacterium tuberculosis strains isolated from sputum samples. To that end, sputum samples were collected from 263 patients suspected of having tuberculosis. All subjects lived in the Complexo de Manguinhos, which is located in the city of Rio de Janeiro, Brazil. Cultures testing positive between October of 2000 and December of 2002 were tested to determine strain susceptibility to isoniazid, rifampicin, streptomycin, ethionamide, and ethambutol. Of the 75 patients diagnosed with tuberculosis, resistance to at least one of the drugs was found in 16 (21.4%). Of those 16 patients, 8 (50%) were new cases, and 8 (50%) had previously been treated. Multidrug-resistant tuberculosis was identified in 8 (10.6%) of the 75 patients, being associated with previous treatment in 6 (8%). The incidence of multidrug-resistant tuberculosis might have been underestimated, since M. tuberculosis was not isolated from all of the samples testing positive for acid-fast bacilli. However, at least, our findings shed some light on the problem.

Keywords: Tuberculosis; Drug resistance; Drug resistance, multiple.

Objective: To evaluate the performance of nested PCR (nPCR) in detecting the Mycobacterium tuberculosis complex in blood samples of patients suspected of having TB, in order to determine its potential for use as an auxiliary tool in the laboratory diagnosis of TB in children. Methods: Detection of the M. tuberculosis complex in blood samples using as a target the insertion sequence IS6110 of the genomic DNA of the bacillus. Blood samples of 120 patients were evaluated. All of the patients were under 15 years of age at the time of their treatment at public hospitals in the city of Recife, Brazil (between January of 2003 and August of 2005). Attending physicians at the hospitals diagnosed TB based on the criteria recommended by the American Thoracic Society. The nPCR amplified a 123-bp fragment with outer oligonucleotides (IS1/IS2) and, in the subsequent reaction, using inner oligonucleotides (IS3/IS4), generating an 81-bp amplicon. Results: Active or latent TB was found in 65 patients, TB was ruled out in 28 suspected cases, and 27 patients were TB-free (controls). The sensitivity of nPCR was 26.15% and was significantly higher for the extrapulmonary form of the disease (55.56%) than for the pulmonary form (18.18%). The specificity was 92.73%. Conclusions: Despite the difficulties in diagnosing TB in children and the low number of cases evaluated in the present study, nPCR in blood samples proved to be a rapid and specific technique, albeit one with low sensitivity. In order to establish its true usefulness in the diagnosis of paucibacillary forms, especially extrapulmonary TB, further studies need to be carried out with a larger sample of children and analyzing biological specimens other than blood.

Keywords: Tuberculosis; Diagnosis; Blood; Polymerase chain reaction.

Objective: To evaluate the impact of the use of the molecular test for Mycobacterium tuberculosis and its resistance to rifampin (Xpert MTB/RIF), under routine conditions, at a referral hospital in the Brazilian state of Bahia. Methods: This was a descriptive study using the database of the Mycobacteriology Laboratory of the Octávio Mangabeira Specialized Hospital, in the city of Salvador, and georeferencing software. We evaluated 3,877 sputum samples collected from symptomatic respiratory patients, under routine conditions, between June of 2014 and March of 2015. All of the samples were submitted to sputum smear microscopy and the Xpert MTB/RIF test. Patients were stratified by gender, age, and geolocation. Results: Among the 3,877 sputum samples evaluated, the Xpert MTB/RIF test detected M. tuberculosis in 678 (17.5%), of which 60 (8.8%) showed resistance to rifampin. The Xpert MTB/RIF test detected M. tuberculosis in 254 patients who tested negative for sputum smear microscopy, thus increasing the diagnostic power by 59.9%. Conclusions: The use of the Xpert MTB/RIF test, under routine conditions, significantly increased the detection of cases of tuberculosis among sputum smear-negative patients.

Keywords: Tuberculosis/diagnosis; Molecular diagnostic techniques; Sputum.

Tuberculosis continues to be a major public health problem worldwide. The aim of the present study was to evaluate the accuracy of the Xpert MTB/RIF rapid molecular test for tuberculosis, using pulmonary samples obtained from patients treated at the Júlia Kubitschek Hospital, which is operated by the Hospital Foundation of the State of Minas Gerais, in the city of Belo Horizonte, Brazil. This was a retrospective study comparing the Xpert MTB/RIF test results with those of standard culture for Mycobacterium tuberculosis and phenotypic susceptibility tests. Although the Xpert MTB/RIF test showed high accuracy for the detection of M. tuberculosis and its resistance to rifampin, attention must be given to the clinical status of the patient, in relation to the test results, as well as to the limitations of molecular tests.

Keywords: Tuberculosis/diagnosis; Molecular diagnostic techniques; Sputum; Bronchoalveolar lavage fluid.

Objective: To assess the diagnostic performance of the Xpert MTB/RIF assay, a rapid molecular test for tuberculosis, comparing it with that of AFB staining and culture, in BAL fluid (BALF) samples from patients with clinically suspected pulmonary tuberculosis (PTB) who are sputum smear-negative or produce sputum samples of insufficient quantity. Methods: This was a retrospective study of 140 cases of suspected PTB in patients who were smear-negative or produced insufficient sputum samples and were evaluated at a tertiary teaching hospital in the city of Rio de Janeiro, Brazil. All of the patients underwent fiberoptic bronchoscopy with BAL. The BALF specimens were evaluated by AFB staining, mycobacterial culture, and the Xpert MTB/RIF assay. Results: Among the 140 patients, results for all three microbiological examinations were available for 73 (52.1%), of whom 22 tested positive on culture, 17 tested positive on AFB staining, and 20 tested positive on the Xpert MTB/RIF assay. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy for AFB staining were 68.1%, 96.1%, 88.2%, 87.5%, and 87.6%, respectively, compared with 81.8%, 96.1%, 90.0%, 92.4%, and 91.8%, respectively, for the Xpert MTB/RIF assay. The agreement between AFB staining and culture was 82.3% (kappa = 0.46; p < 0.0001), whereas that between the Xpert MTB/RIF assay and culture was 91.8% (kappa = 0.8; p < 0.0001). Conclusions: In BALF samples, the Xpert MTB/RIF assay performs better than do traditional methods, providing a reliable alternative to sputum analysis in suspected cases of PTB. However, the rate of discordant results merits careful consideration.

Keywords: Tuberculosis; Molecular diagnostic techniques; Bronchoscopy; Bronchoalveolar lavage fluid; Mycobacterium tuberculosis.

Objective: Nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria that are widely distributed in nature and associated with opportunistic infections in humans. The aims of this study were to identify NTM in patients with suspected tuberculosis who pre-sented positive cultures and to evaluate the genetic diversity of strains identified as Myco-bacterium avium. Methods: We studied pulmonary and extrapulmonary samples obtained from 1,248 patients. The samples that tested positive on culture and negative for the M. tu-berculosis complex by molecular identification techniques were evaluated by detection of the hsp65 and rpoB genes and sequencing of conserved fragments of these genes. All strains identified as M. avium were genotyped using the eight-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat method. Results: We found that NTM ac-counted for 25 (7.5%) of the 332 mycobacteria isolated. Of those 25, 18 (72%) were M. avium, 5 (20%) were M. abscessus, 1 (4%) was M. gastri, and 1 (4%) was M. kansasii. The 18 M. avium strains showed high diversity, only two strains being genetically related. Conclusions: These results highlight the need to consider the investigation of NTM in patients with suspected active tuberculosis who present with positive cultures, as well as to evaluate the genetic di-versity of M. avium strains.

Keywords: Mycobacterium avium; Nontuberculous mycobacteria; HIV; Genotyping techniques.

We compared the nitrate reductase assay with the proportion method, which is considered the gold standard, in 57 Mycobacterium tuberculosis strains isolated from patients treated at the Federal University of Minas Gerais Hospital das Clínicas, located in the city of Belo Horizonte, Brazil. For rifampin and isoniazid, the sensitivity, specificity, and accuracy of the nitrate reductase assay were all 100%, whereas they were 100%, 88.9%, and 66.7%, respectively, for streptomycin and 98.0%, 100%, and 98.2%, respectively, for ethambutol. The mean time to results was ten days. In the study sample, the nitrate reductase assay proved highly accurate and showed excellent concordance with the gold standard.

Keywords: Mycobacterium tuberculosis; Microbial sensitivity tests; Tuberculosis, multidrug-resistant; Nitrate reductase.

Objective: To analyze and compare the mutations in two different regions of the katG gene, which is responsible for isoniazid (INH) resistance. Methods: We analyzed 97 multidrug-resistant Mycobacterium tuberculosis strains isolated in cultures of sputum samples obtained from the Professor Hélio Fraga Referral Center, in Brasília, Brazil. Another 6 INH-sensitive strains did not present mutations and were included as controls. We used PCR to amplify two regions of the katG gene (GenBank accession no. U06258)-region 1, (from codon 1 to codon 119) and region 2 (from codon 267 to codon 504)-which were then sequenced in order to identify mutations. Results: Seven strains were resistant to INH and did not contain mutations in either region. Thirty strains carried mutations in region 1, which was characterized by a high number of deletions, especially at codon 4 (24 strains). Region 2 carried 83 point mutations, especially at codon 315, and there was a serine-to-threonine (AGC-to-ACC) substitution in 73 of those cases. The analysis of region 2 allowed INH resistance to be diagnosed in 81.4% of the strains. Nine strains had mutations exclusively in region 1, which allowed the proportion of INH-resistant strains identified to be increased to 90.6%. Conclusions: The number of mutations at codon 315 was high, which is consistent with cases described in Brazil and in other countries, and the analysis of region 1 resulted in a 9.2% increase in the rate at which mutations were identified.

Keywords: Isoniazid; Mutation; Tuberculosis; Drug resistance, multiple.

Background: Tuberculosis is an ancient disease, which still remains one of the major ills faced by mankind in the 21st century. In recent decades, new technologies employing the knowledge gained from molecular biology studies have allowed for more accurate detection of tuberculosis and increased investigation of the etiology and epidemiology of the disease. Aim: Evaluating the degree of similarity among strains of Mycobacterium tuberculosis provided by the Phthisiology Sector of Centro de Saúde Navegantes (Navegantes Health Clinic) in Porto Alegre, RS, Brazil. Method: A retrospective study was performed involving RFLP typing of 55 sputum samples from outpatients examined at the Centro de Saúde Navegantes. The results of the genotyping were correlated to the conventional epidemiology data. Results: A single pattern was seen in 39 (70.9%) of the isolates, whereas 16 isolates (29.1%) showed clustering patterns and were grouped into 8 clusters of 2 patients each. An epidemiological link was found for 6 (37.5%) of the 16 patients in the clusters. Conclusion: The appropriate combination of conventional epidemiology and genotyping of M. tuberculosis contributes to a better understanding of the dynamics of tuberculosis transmission even when such a study is performed in a single, isolated health clinic.

Keywords: Mycobacterium tuberculosis. Transmission. Polymorphism, Restriction Fragment Length. Epidemiology.

Objective: To develop a system for the molecular diagnosis of tuberculosis by polymerase chain reaction (PCR), constructing primers based on the difference in gene organization of the intergenic region of phospholipase C (plcB-plcC region), which differentiates Mycobacterium tuberculosis from other mycobacteria. Methods: A PCR product of the expected size (432 bp) was obtained from M. tuberculosis and M. africanum only. A total of 33 mycobacterial isolates and 273 clinical samples from patients suspected of having tuberculosis were examined. These were used in the comparative study of the PCR technique versus culture. Results: For PCR versus culture, the data showed 93.8% accuracy (p < 0.0001), 93.1% sensitivity (CI: 88.7-96.0), and 96.4% specificity (CI: 96.1-99.4). The Kappa value (0.82) shows that there was a near-perfect concordance between the two tests. Conclusion: The use of the plcB-plcC region in PCR amplification was found to be an important and reliable tool for the specific diagnosis of tuberculosis in the samples analyzed.

Keywords: Polymerase chain reaction; Diagnosis; Tuberculosis; Mycobacterium tuberculosis

Objective: To identify mycobacterial species in the sputum of patients suspected of having pulmonary tuberculosis and to determine the impact that the acquisition of this knowledge has on the therapeutic approach. Methods: We evaluated 106 patients suspected of having pulmonary tuberculosis and referred to the pulmonology department of a public hospital in the city of Teresina, Brazil. Morning sputum specimens were evaluated for the presence of mycobacteria by sputum smear microscopy and culture. We used PCR and restriction enzyme analysis of the hsp65 gene (PRA-hsp65) to identify the strains of mycobacteria isolated in culture. Results: A total of 206 sputum samples were analyzed. Patient ages ranged from 15 to 87 years, and 67% were male. There was cough in 100% of the cases. The predominant radiographic pattern was moderate disease, observed in 70%. Smear positivity was 76%, and isolation in culture occurred in 91% of the cultures. Traditional tests identified nontuberculous mycobacteria (NTM) in 9% of the isolates. The PRA-hsp65 method confirmed these data, showing seven band patterns that were able to identify the isolated species of NTM: Mycobacterium kansasii; M. abscessus 1; M. abscessus 2; M. smegmatis; M. flavescens 1; M. gordonae 5; and M. gordonae 7. All of the patients with NTM were over 60 years of age, and bronchiectasis was seen in 88% of the X-rays. There were two cases of reinfection, initially attributed to M. abscessus and M. kansasii. Conclusions: In immunocompetent patients, NTM can infect the lungs. It is important to identify the specific NTM in order to establish the correct diagnosis and choose the most appropriate therapeutic regimen. The PRA-hsp65 method is useful in identifying NTM species and can be implemented in molecular biology laboratories that do not specialize in the identification of mycobacteria. Keywords:

Keywords: Tuberculosis; Mycobacteria, atypical; Polymerase chain reaction; Brazil.

Objective: To develop and validate a Portuguese-language version of the Asthma Control Test (ACT) for use in Brazil. Methods: The study comprised 290 asthma outpatients over 12 years of age. The patients completed the ACT questionnaire and had an appointment with a pulmonologist in order to assess asthma control in two visits. In the first visit, the patients also underwent spirometry. The second visit took place at least four weeks later. Results: We found that a cut-off score of 18 points-to differentiate between subjects with controlled asthma and those with uncontrolled asthma-had a sensitivity of 93%, a specificity of 74%, a negative predictive value of 86% and a positive predictive value of 85%. The positive and negative likelihood ratios were 3.58 and 0.09, respectively. The questionnaire has an outstanding capacity to differentiate uncontrolled asthma from controlled asthma, with an area under the ROC curve of 0.904. The patients whose symptoms remained stable between the two visits had similar scores, demonstrating good test-retest reproducibility, with an intraclass correlation coefficient of 0.93. The patients whose symptoms improved in the second visit had significantly higher scores, demonstrating good responsiveness of the questionnaire in the identification of changes in disease control. Conclusions: The Portuguese-language version of the ACT showed good test-retest reproducibility and was capable of discriminating the levels of asthma control and detecting changes in asthma control in a population of patients with a low level of education and low family income at a public health facility in Brazil.

Keywords: Asthma; Questionnaires; Validation studies; Signs and symptoms.

Objective: To validate a Portuguese-language version of the COPD assessment test (CAT) for use in Brazil and to assess the reproducibility of this version. Methods: This was multicenter study involving patients with stable COPD at two teaching hospitals in the city of Fortaleza, Brazil. Two independent observers (twice in one day) administered the Portuguese-language version of the CAT to 50 patients with COPD. One of those observers again administered the scale to the same patients one week later. At baseline, the patients were submitted to pulmonary function testing and the six-minute walk test (6MWT), as well as completing the previously validated Portuguese-language versions of the Saint George's Respiratory Questionnaire (SGRQ), modified Medical Research Council (MMRC) dyspnea scale, and hospital anxiety and depression scale (HADS). Results: Inter-rater and intra-rater reliability was excellent (intraclass correlation coefficient [ICC] = 0.96; 95% CI: 0.93-0.97; p < 0.001; and ICC = 0.98; 95% CI: 0.96-0.98; p < 0.001, respectively). Bland & Altman plots showed good test-retest reliability. The CAT total score correlated significantly with spirometry results, 6MWT distance, SGRQ scores, MMRC dyspnea scale scores, and HADS-depression scores. Conclusions: The Portuguese-language version of the CAT is a valid, reproducible, and reliable instrument for evaluating patients with COPD in Brazil.

Keywords: Pulmonary disease, chronic obstructive; Questionnaires; Validation studies; Quality of life; Reproducibility of results.

Objective: To translate The Manchester Respiratory Activities of Daily Living (MRADL) questionnaire into Portuguese and to create a version of the MRADL that is cross-culturally adapted for use in Brazil. Methods: The English-language version of the MRADL was translated into Portuguese by two health care researchers who were fluent in English. A consensus version was obtained by other two researchers and a pulmonologist. That version was back-translated into English by another translator who was a native speaker of English and fluent in Portuguese. The cognitive debriefing process consisted in having 10 COPD patients complete the translated questionnaire in order to test its understandability, clarity, and acceptability in the target population. On the basis of the results, the final Portuguese-language version of the MRADL was produced and approved by the committee and one of the authors of the original questionnaire. Results: The author of the MRADL questioned only a few items in the translated version, and some changes were made to the mobility and personal hygiene domains. Cultural differences regarding the domestic activities domain were found, in particular regarding the item "Do you have the ability to do a full clothes wash and hang them out to dry?", due to socioeconomic and climatic issues. The item "Do you take care of your garden?" was questioned by the participants who lived in apartments, being modified to "Do you take care of your garden or plants in your apartment?" Conclusions: The final Portuguese-language version of the MRADL adapted for use in Brazil was found to be easy to understand and easily applied.

Keywords: Activities of daily living; Questionnaires; Translations; Pulmonary disease, chronic obstructive.

Objective: To determine the current use and potential acceptance (by tuberculosis experts worldwide) of novel rapid tests for the diagnosis of tuberculosis that are in line with World Health Organization target product profiles. Methods: A multilingual survey was disseminated online between July and November of 2016. Results: A total of 723 individuals from 114 countries responded to the survey. Smear microscopy was the most commonly used rapid tuberculosis test (available to 90.9% of the respondents), followed by molecular assays (available to 70.7%). Only a small proportion of the respondents in middle- and low-income countries had access to interferon-gamma-release assays. Serological and lateral flow immunoassays were used by more than a quarter (25.4%) of the respondents. Among the respondents who had access to molecular tests, 46.7% were using the Xpert assay overall, that proportion being higher in lower middle-income countries (55.6%) and low-income countries (76.6%). The data also suggest that there was some alignment of pricing for molecular assays. Respondents stated they would accept novel rapid tuberculosis tests if available, including molecular assays (acceptable to 86.0%) or biomarker-based serological assays (acceptable to 81.7%). Simple biomarker-based assays were more commonly deemed acceptable in middle- and low-income countries. Conclusions: Second-generation molecular assays have become more widely available in high- and low-resource settings. However, the development of novel rapid tuberculosis tests continues to be considered important by tuberculosis experts. Our data also underscore the need for additional training and education of end users.

Keywords: Tuberculosis/diagnosis; Surveys and questionnaires; Income; Mycobacterium tuberculosis/isolation & purification; Molecular diagnostic techniques/methods; Serologic tests/methods.

Objective: To evaluate clinical aspects and the diagnosis of pulmonary tuberculosis (PT) in the aged. Methods: We compared 117 patients over 60 years of age (elderly group) and 464 patients aged 15 to 49 years old (nonelderly group) treated at the Thoracic Diseases Institute of the Federal University of Rio de Janeiro, from 1980 to 1996. Results: Previous history of PT was predominant in the elderly group (OR = 2.09; 95% CI = 1.26-3.45; p = 0.002), whereas household contact with PT was predominant in the nonelderly group (OR = 0.26; 95% CI = 0.10-0.66; p = 0.002). Mean time for diagnosis was 90 days in the elderly group and 60 days in the nonelderly group. In the elderly group, dyspnea (OR = 1.64; 95% CI = 1.06-2.53; p = 0.018) and weight loss (OR = 1.66; 95% CI = 1.01-2.82; p = 0.047) were predominant. In the nonelderly group, hemoptysis (OR = 0.51; 95% CI = 0.32-0.81; p = 0.002), chest pain (OR = 0.62; 95% CI = 0.40-0.97; p = 0.027) and fever (OR = 0.55; 95% CI = 0.35-0.86; p = 0.006) were more common. The most common radiological abnormalities were infiltrates and cavitations. Bilateral involvement was more common in the elderly patients (OR = 1.76; 95% CI = 1.12-2.78; p = 0.009). There were no differences between the two groups regarding positivity for Mycobacterium tuberculosis identified through tuberculin skin testing, sputum smear microscopy and culture. Conclusions: There are few clinical and laboratory differences between the age groups. The delayed diagnosis in the elderly group can be explained by the low clinical suspicion in these patients.

Keywords: Tuberculosis, pulmonary; Aged; Signs and symptoms, respiratory; Diagnosis.

We conducted a cross-sectional, retrospective study, characterized by classical and molecular epidemiology, involving M. tuberculosis isolates from a regional prison in southern Brazil. Between January of 2011 and August of 2014, 379 prisoners underwent sputum smear microscopy and culture; 53 (13.9%) were diagnosed with active tuberculosis. Of those, 8 (22.9%) presented with isoniazid-resistant tuberculosis. Strain genotyping was carried out by 15-locus mycobacterial interspersed repetitive unit-variable-number tandem-repeat analysis; 68.6% of the patients were distributed into five clusters, and 87.5% of the resistant cases were in the same cluster. The frequency of drug-resistant tuberculosis cases and the rate of recent transmission were high. Our data suggest the need to implement an effective tuberculosis control program within the prison system.

Keywords: Tuberculosis; Prisons; Molecular epidemiology.

Objective: To determine the drug resistance profile of Mycobacterium tuberculosis in the state of Mato Grosso do Sul, Brazil, between 2000 and 2006. Methods: Descriptive study of reported tuberculosis cases in the Brazilian Case Registry Database. We included only those cases in which M. tuberculosis culture was positive and sensitivity to drugs (rifampicin, isoniazid, streptomycin and ethambutol) was tested. Löwenstein-Jensen and Ogawa-Kudoh solid media were used for cultures, as was an automated liquid medium system. Sensitivity tests were based on the proportion method. Results: Among the 783 cases evaluated, males predominated (69.7%), as did patients in the 20-49 year age bracket (70%), a diagnosis of pulmonary tuberculosis (94.4%) and positive HIV serology (8.6%); 645 (82.4%) were new cases, and 138 (17.6%) had previously been treated. Resistance to at least one drug was found in 143 cases (18.3%). The primary resistance (PR) rate was, respectively, 8.1%, 1.6%, 2.8% and 12.4%, for monoresistance, multidrug resistance (MDR), other patterns of resistance and resistance to at least one drug, whereas the acquired resistance (AR) rate was 14.5%, 20.3%, 10.9% and 45.7%, respectively, and the combined resistance (CR) rate was 9.2%, 4.9%, 4.2% and 18.3%, respectively. In PR, streptomycin was the most common drug, whereas isoniazid was the most common in AR and CR (7.2% and 3.7%, respectively). Conclusions: These high levels of resistance undermine the efforts for tuberculosis control in Mato Grosso do Sul. Acquired MDR was 12.7 times more common than was primary MDR, demonstrating that the previous use of drug therapy is an indicator of resistance. These levels reflect the poor quality of the health care provided to these patients, showing the importance of using the directly observed treatment, short course strategy, as well as the need to perform cultures and sensitivity tests for the early diagnosis of drug resistance.

Keywords: Tuberculosis; Drug resistance, multiple; Mycobacterium tuberculosis.

This retrospective molecular study involving restriction fragment length polymorphism, using insertion sequence 6110 as a marker, was conducted in order to provide an initial insight into the genetic diversity of Mycobacterium tuberculosis strains isolated in the slums of the Complexo de Manguinhos, located in the city of Rio de Janeiro, Brazil. Of the 67 strains evaluated, 23 (34.3%) were found to belong to clusters (total clusters, 10). Household and social chains of transmission were associated with clustering, in 20% and 60%, respectively. Living in the Conjunto Habitacional Programado 2 slum was associated with clustering. Although not significant, it is relevant that 26% of the clustered strains presented primary resistance. These findings, although possibly underestimating the prevalence due to the failure to analyze all strains, could help improve the local tuberculosis control program.

Keywords: Tuberculosis; Epidemiology, molecular; Mycobacterium tuberculosis/transmission; Polymorphism, Restriction Fragment Length.