Mycobacterium tuberculosis is one of the most successful human pathogens. Highly virulent strains, which are more easily transmitted than are less virulent strains, elicit variable immune responses. We evaluated the Th1 responses (IFN-γ production) in healthy volunteers after stimulation with various strains. Our results show that the individuals with negative tuberculin skin test (TST) results were not necessarily naive to all of the strains tested, whereas individuals with positive TST results did not respond to all of the strains tested. Drug-resistant strains induced a lower mean level of IFN-γ production than did drug-sensitive strains. One possible practical application of this finding would be for the prediction of responses to treatment, in which it might be advantageous to have knowledge of the estimated IFN-γ production elicited by a specific isolated strain.

Keywords: Tuberculosis; Polymorphism, restriction fragment length; Mycobacterium tuberculosis; Immunity, cellular; Interferon-gamma.

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.

In 2005 and 2006, 8,121 clinical specimens submitted to the Mycobacteriology Laboratory of the Clementino Fraga Filho University Hospital/Thoracic Diseases Institute, in the city of Rio de Janeiro, Brazil, were inoculated on Löwenstein-Jensen medium containing glycerol and pyruvate. There were 79 mycobacteria isolates that presented growth only on pyruvate-containing medium, and those isolates were selected for the presumptive identification of Mycobacterium bovis. The selected isolates were screened with biochemical tests, PCR amplification (with the specific primers Rv0577 and Rv1510), and pyrazinamide susceptibility tests. All of the strains isolated showed specific phenotypical and genotypical patterns characteristic of M. tuberculosis, and no M. bovis strains were detected.

Keywords: Tuberculosis; Mycobacterium bovis; Polymerase chain reaction.

To describe some aspects of tuberculosis in a low-income community (the Complexo de Manguinhos, in Rio de Janeiro, Brazil), a retrospective study was carried out. Of the 290 cases reported in the 2000-2002 period, 75.8% were new cases. The annual incidence rates were 157/100,000 (2000), 205/100,000 (2001), and 145/100,000 (2002). Although there was a tendency toward a decrease in the number of cases over the period studied, the difference was not significant, suggesting that tuberculosis continues to be endemic in the area. Therefore, despite the existence of local public health care services, more efficient strategies should be implemented in order to increase the effectiveness of tuberculosis control programs in the area.

Keywords: Tuberculosis/epidemiology; Poverty areas; 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.

Introduction: The teaching hospital, HUCFF, Southeastern Brazil, annually receives three hundred tuberculosis cases. Medical students have their practice at that hospital. Objective: To determine the prevalence of Mycobacterium tuberculosis (Mtb) infection among the students of the UFRJ School of Medicine. Design: Cross-sectional study of medical students at different levels of their training programs. Information about social and demographic characteristics, BCG vaccination history, and potential exposures to tuberculosis were obtained with a standardized questionnaire. Tuberculin skin testing was used to determine the prevalence of tuberculosis infection. Results: The prevalence of tuberculin skin testing positivity among medical students increased as they advanced to higher training levels (4.6%, 7.8%, 16.2%, respectively; P = 0.002). The risks were greatest during the years of clinical training, when medical students had more contact with patients. Conclusions: Medical students in the HUCFF/UFRJ may be at an increased risk of M. tuberculosis infection. A program of routine tuberculin skin testing, combined with interventions to confirm TST conversion and to reduce the risk of nosocomial transmission in the workplace is needed.

Keywords: Nosocomial infection. Medical students. Risk factors. Cross-sectional studies.

Background: Tuberculosis become important challenge to health care settings. Brazil has high prevalence of the disease and Rio de Janeiro has high incidence rates with 30% of cases notified at hospitals. Objective: To evaluate prevalence of initial and acquired drug resistance at a general hospital, reference for aids treatment in Rio de Janeiro and to identify associated factors. Methods: Mycobacterium tuberculosis strains from 165 patients were analyzed, between August 1996 and February 1998. Results: Twenty per cent (33/165) were resistant to at least one drug; 13% (12/165) to isoniazid; 3.64% (6/ 165) to rifampin and 3.64% (6/165) to both. Among HIV seropositive subjects (52/165); 28.85% (15/52) were resistant to at least one drug. Acquired resistance occurred in 15.79% of 19 patients that mentioned previous antiTB treatment. Association statistically significant was found with non cavitation on X-ray in bivariate analyses ( P=0.05). Eighty four patients refereed no previous treatment (NPT). Resistance to 1 or more drugs was found in 28.57% (24/84) of NPT patients. Association statistically significant with initial resistance was found with health care workers (P=0.004), unemployment (P=0.03), and diarrhea (P=0.01) in bivariate analyses. On multivariate analyses, health care workers ( P=0.002) remained significantly associated with initial resistance. Conclusions: High resistance rates was found. It corroborates that hospitals needs attention for TB control especially which concerns to health care works infection.

Keywords: Mycobacterium tuberculosis. Drug resistance. Disease transmission, patient to professional. Hospitals.

Introduction: There have been few Latin American studies investigating the fact that the rate of tuberculosis (TB) infection among medical students is higher than the 1.3% rate seen in the population at large. Objective: To describe the cumulative incidence and the relative risk for TB infection among medical students. Method: In 1998, a prospective cohort study was conducted involving medical students at the Universidade Federal do Rio de Janeiro Faculdade de Medicina who tested negative (induration <10 mm) on the tuberculin skin test (TST). Students were tested using the two-step TST method and were retested one year later. The students tested were at two different stages in their training: pre-clinical (no contact with patients) and final year (contact with patients). Information about demographic characteristics, BCG vaccination history, and instances of potential exposure to Mycobacterium tuberculosis were obtained using a standardized questionnaire. Of the 575 students initially enrolled, 72% (414) completed the study. Results: The TSTs of 16 (3.9%) of the 414 students converted, representing a cumulative incidence of 3.9% (95% confidence interval = 1.06 to 12.1). Senior medical students were at an almost fourfold higher risk for M. tuberculosis infection than were those in pre-clinical training. Conclusion: The risk for TST conversion is very high in this population.

Keywords: PPD. Tuberculosis-infection. Tuberculin conversion. Medical students

In view of the fact that the World Health Organization has recommended the use of the mycobacteria growth indicator tube (MGIT) 960 system for the diagnosis of tuberculosis and that there is as yet no evidence regarding the clinical impact of its use in health care systems, we conducted a pragmatic clinical trial to evaluate the clinical performance and cost-effectiveness of the use of MGIT 960 at two health care facilities in the city of Rio de Janeiro, Brazil, where the incidence of tuberculosis is high. Here, we summarize the methodology and preliminary results of the trial. (ISRCTN.org Identifier: ISRCTN79888843 [http://isrctn.org/])

Keywords: Controlled clinical trial; Tuberculosis; Diagnostic tests, routine.

Os bacilos que causam a tuberculose estão agrupados no complexo Mycobacterium tuberculosis, composto por: M. tuberculosis, M. bovis subsp. bovis, M. africanum e M. microti, além da cepa vacinal M. bovis BCG. Tem sido proposta a inclusão de novas espécies neste complexo, como M. canettii, uma variante de M. tuberculosis encontrada na região da Somália(1), M. caprae, agente etiológico de tuberculose em caprinos(2), e M. pinnipedii, que causa tuberculose em leões marinhos, mas que também pode infectar o homem(3).

We report a rare case in a female infant (age, 3.5 months) with primary immunodeficiency (IFN-γ/IL-12 pathway defect) who presented with suppurative lymphadenitis after Mycobacterium bovis BCG vaccination. The strain of M. bovis BCG identified was found to be resistant to isoniazid and rifampin. The patient was treated with a special pharmacological regimen involving isoniazid (in a limited, strategic manner), ethambutol, streptomycin, and IFN-γ, after which there was complete resolution of the lesions.

Keywords: BCG vaccine; Interferon-gamma; Tuberculosis, multidrug-resistant.

The objective of this study was to compare gender differences among tuberculosis patients in a city with a high incidence of tuberculosis. This was a cross-sectional questionnaire-based study involving 560 tuberculosis patients (373 males and 187 females). Sociodemographic and clinical data, as well as data related to diagnostic criteria and treatment outcome, were collected (from the questionnaires and medical records) and subsequently compared between the genders. The median time from symptom onset to diagnosis was 90 days. There were no differences between the genders regarding the clinical presentation, diagnostic criteria, previous noncompliance with treatment, time from symptom onset, number of medical appointments prior to diagnosis, or treatment outcome. Gender-specific approaches are not a priority in Brazil. However, regardless of patient gender, the delay in diagnosis is a major concern.

Keywords: Poverty; Tuberculosis; Income.

Objective: To estimate the total time elapsed between symptom onset and diagnosis of pulmonary tuberculosis (patient delay plus health care system delay), analyzing the factors associated with delayed diagnosis in the state of Rio de Janeiro, Brazil. Methods: We conducted a questionnaire-based survey involving 218 pulmonary tuberculosis patients treated for two months at 20 health care clinics and 3 hospitals in eight cities within the state of Rio de Janeiro. We collected socioeconomic and demographic data, as well as data regarding the health care system and the medical history of the patients. Results: The median time elapsed from the onset of symptoms to diagnosis was 68 days (interquartile range [IQR]: 35-119 days). The median patient delay (time from symptom onset to initial medical visit) was 30 days (IQR: 15-60 days), and the median health care system delay (time from initial medical visit to diagnosis) was 21 days (IQR: 8-47 days). A cut-off point of 21 days was adopted. The factors independently associated with patient delay were female gender, cough, and unemployment [adjusted OR (95% CI) = 2.7 (1.3-5.6); 11.6 (2.3-58.8); and 2.0 (1.0-3.8), respectively], whereas only female gender was independently associated with health care system delay (OR= 3.2; 95% CI: 1.7-6.0). Conclusions: Delayed diagnosis of pulmonary tuberculosis remains a problem in Rio de Janeiro, increasing the risk of transmission and mortality, that risk being greater for women and the socioeconomically disadvantaged. Patients might not recognize the significance of chronic cough as a health problem. Tuberculosis education programs targeting women might improve this situation.

Keywords: Lung neoplasms; Neoplasm metastasis; Antineoplastic combined chemotherapy protocols; Radiotherapy, computer-assisted.

Background: In 1998, tuberculosis incidence and mortality rates in the state of Rio de Janeiro (RJ) were the highest in Brazil. However, the RJ tuberculosis database (SINAN-TBRJ) has proven unreliable. Objective: To evaluate the current tuberculosis control program by analyzing tuberculosis-attributed deaths. Methods: Descriptive studies of the SINAN-TB-RJ and tuberculosis mortality (SIM-TB-RJ) databases were carried out. Both databases were linked using the Reclink program. A study based on medical records was performed in the five hospitals where the greatest numbers of tuberculosis deaths occurred. Results: In the SINAN-TB-RJ database, 16,567 cases were registered in adults (> 14 years of age). Pulmonary disease was present in 13,989 (84.5%), of whom 8223 (56.8%) presented sputum smears that were positive for acid fast bacilli. Anti-HIV testing, recommended for all patients with tuberculosis, was performed in only 4141 (25%) of tuberculosis cases. The SIM-TB-RJ database showed 1146 deaths that were attributed to tuberculosis. Only 478 (41.7%) of those had been reported to the health care system (SINAN-TB-RJ). Among the 302 medical records analyzed, 154 (50.9%)recorded hospitalizations of up to 10 days and 143 (47.3%) had respiratory symptoms for more than 60 days before diagnosis. Among 125 cases of retreatment, the RHZE regimen recommended by the Brazilian Ministry of Health was prescribed for only 43 (34.4%). Conclusion: This study demonstrates weakness in the RJ tuberculosis control program, characterized by delayed diagnosis, limited use of the recommended tests, poor reporting, and non-compliance with the Ministry of Health guidelines.

Keywords: Tuberculosis. Epidemiology. Program Evaluation

Background: The Hospital Ferreira Machado, utilized, in part, as a clinical training center for graduate students from the Faculdade de Medicina de Campos, admitted 65 tuberculosis (TB) patients in 2001. Objective: To estimate the prevalence of positive tuberculin skin tests (TST) among medical students during distinct periods of their training and to identify and analyze correlated factors. To compare positivity rates, taking into account the booster effect, and estimate incidence of positive TST by class year. Methods: A cross-sectional study was conducted among 500 students registered in the first semester of 2002. Using a structured and validated questionnaire, data regarding demographics, BCG vaccination and potential exposure to TB patients were obtained. A professional licensed by the Health Department administered the TSTs, and the twostep Mantoux method (PPD Rt23) was used. Results: Of the 500 eligible subjects, 316 (63.2%) were excluded. Analysis showed increasing two-step TST positivity rates corresponding to extent of clinical experience (4%, 6.4% and 13.1%) and a tendency toward correlation with professional level. The highest percentage of positive TSTs was found during the period of clinical training, which corresponded to the time of greatest exposure to patients (1000 hours). Conclusions: a) the TST positivity rate was high (7.9%) among students; b) TST was correlated with in-hospital training stage; c) evaluation of the booster effect lead us to highly recommended boosters in order to reduce the number of false-negative TST results.

Keywords: Tuberculin. Tuberculin test. Tuberculosis. Students/Medical. Cross-sectional studies.

Objective: To analyze the epidemiological characteristics of sarcoidosis patients in the city of Rio de Janeiro, Brazil. Methods: A descriptive, case-control study involving 100 sarcoidosis patients under outpatient treatment between 2008 and 2010 at the Pedro Ernesto University Hospital, located in the city of Rio de Janeiro, Brazil. The diagnosis of sarcoidosis was based on clinical, radiological, biochemical, and histopathological criteria. Results: There was a predominance of females in the 35-40 year age bracket (range, 7-69 years), who accounted for 65% of the sample, although there was a second peak at approximately 55 years of age. The most common symptom was dyspnea (in 47%), and the most common radiological findings were pulmonary and lymph node involvement (stage II; in 43%), followed by stage III (in 20%), stage I (in 19%), stage 0 (in 15%), and stage IV (in 3%). No pleural effusion or digital clubbing was observed at diagnosis. The tuberculin skin test was negative in 94 patients. Spirometric findings at diagnosis were normal in 61 patients; indicative of obstructive lung disease in 21; and indicative of restrictive lung disease in 18. The most common biopsy sites were the lungs (principally by bronchoscopy) and the skin, the diagnosis being confirmed by biopsy in 56% and 29% of the cases, respectively. Treatment with prednisone was initiated in 75% of the patients and maintained for more than 2 years in 19.7%. Conclusions: This study corroborates the findings of previous studies regarding the epidemiological characteristics of sarcoidosis patients.

Keywords: Sarcoidosis/epidemiology; Sarcoidosis/diagnosis; Sarcoidosis/therapy.

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.

Objective: To describe the clinical and therapeutic aspects of pulmonary tuberculosis and compare the adverse effects of the treatment and its outcome in elderly and nonelderly patients. Methods: This was a case-control study of 117 elderly individuals (over the age of 60 years) and 464 nonelderly individuals (aged 15-49 years). All subjects presented pulmonary tuberculosis that had been diagnosed and treated at the Thoracic Diseases Institute of the Federal University of Rio de Janeiro between 1980 and 1996. Results: In the elderly group, pulmonary tuberculosis was found to be correlated with diabetes (OR = 3.98; 95% CI = 2.07-7.65; p = 0.001), lung disease (OR = 7.24; 95% CI = 3.64‑14.46; p = 0.001) and heart disease (OR = 5.86; 95% CI = 2.88-11.95; p = 0.001). Smoking (OR = 2.07; 95% CI = 1.26‑3.42; p = 0.002) and alcohol abuse (OR = 1.63; 95% CI = 1.01-2.68; p = 0.041) were also more common in the elderly group. In the elderly group, the treatment more frequently resulted in adverse reactions (OR = 1.62; 95% CI = 1.04-2.54; p = 0.024), especially gastrointestinal reactions (OR = 1.64; 95% CI = 1.01-2.77; p = 0.047), and treatment efficacy was lower: cure rate, 51%; mortality rate, 24%. Treatment adherence was low (approximately 77%) in both groups. Conclusions: In the elderly group, adverse reactions were more common, treatment outcomes were less favorable, there was a greater frequency of clinical complications and deaths related to drug toxicity, and the prevalence of concomitant diseases was higher.

Keywords: Tuberculosis, pulmonary; Aged; Drug therapy; Treatment outcome.

Objective: To describe the difficulties and peculiarities encountered by health professionals during the treatment and investigation of contacts of tuberculosis (TB) patients in disadvantaged communities. Methods: A qualitative study carried out at health care facilities in Health Programming Area 1.0, located in the city of Rio de Janeiro, Brazil, which has a TB incidence rate of 240/100,000 inhabitants. From among the professionals responsible for visiting and treating TB cases and their contacts, two home visit agents and one clinical nurse were selected to be interviewed for the study. Data were transcribed and structured in the form of quotations, emphasizing the predominant ideas. Results: The central ideas focus on the issue of violence, one significant facet of which is the set of rules imposed by narcotraffickers, and on the barriers to the movement of patients/health professionals for TB treatment, as well as on public safety (police). Conclusion: This study provides public health officials, as well as institutions that graduate health professionals, data for reflection and analysis of the difficulties that urban violence creates for the control of TB in a disadvantaged community.

Keywords: Tuberculosis; Prevention and control; Violence; Directly observed therapy; Community health nursing.