Objective: To evaluate the diagnostic performance of the rapid shallow breathing index (RSBI) in predicting extubation failure among adult patients in the intensive care unit and to determine the appropriateness of the classical RSBI cut-off value. Methods: This was a prospective study conducted in the adult intensive care unit of the Botucatu School of Medicine Hospital das Clínicas. The RSBI was evaluated in 73 consecutive patients considered clinically ready for extubation. Results: The classical RSBI cut-off value (105 breaths/min/L) presented a sensitivity of 20% and a specificity of 95% (sum = 115%). Analysis of the receiver operator characteristic (ROC) curve revealed a better cut-off value (76.5 breaths/min/L), which presented a sensitivity of 66% and a specificity of 74% (sum = 140%). The area under the ROC curve for the RSBI was 0.78. Conclusions: The classical RSBI cut-off value proved inappropriate, predicting only 20% of the cases of extubation failure in our sample. The new cut-off value provided substantial improvement in sensitivity, with an acceptable loss of specificity. The area under the ROC curve indicated that the discriminative power of the RSBI is satisfactory, which justifies the validation of this index for use.

Keywords: Adult; Intensive care; ROC curve; Ventilator weaning; Diagnosis; Respiration, artificial.

Objective: To determine whether the predictive accuracy of clinical judgment alone can be improved by supplementing it with an objective weaning protocol as a decision support tool. Methods: This was a multicenter prospective cohort study carried out at three medical/surgical ICUs. The study involved all consecutive difficult-to-wean ICU patients (failure in the first spontaneous breathing trial [SBT]), on mechanical ventilation (MV) for more than 48 h, admitted between January of 2002 and December of 2005. The patients in the protocol group (PG) were extubated after a T-piece weaning trial and were compared with patients who were otherwise extubated (non-protocol group, NPG). The primary outcome measure was reintubation within 48 h after extubation. Results: We included 731 patients-533 (72.9%) and 198 (27.1%) in the PG and NPG, respectively. The overall reintubation rate was 17.9%. The extubation success rates in the PG and NPG were 86.7% and 69.6%, respectively (p < 0.001). There were no significant differences between the groups in terms of age, gender, severity score, or pre-inclusion time on MV. However, COPD was more common in the NPG than in the PG (44.4% vs. 17.6%; p < 0.001), whereas sepsis and being a post-operative patient were more common in the PG (23.8% vs. 11.6% and 42.4% vs. 26.4%, respectively; p < 0.001 for both). The time on MV after the failure in the first SBT was higher in the PG than in the NPG (9 ± 5 days vs. 7 ± 2 days; p < 0.001). Conclusions: In this sample of difficult-to-wean patients, the use of a weaning protocol improved the decision-making process, decreasing the possibility of extubation failure.

Keywords: Ventilator weaning; Ventilation; Ventilators, mechanical.

Objective: The use of the rapid shallow breathing index (RSBI) is recommended in ICUs, where it is used as a predictor of mechanical ventilation (MV) weaning success. The aim of this study was to compare the performance of the RSBI calculated by the traditional method (described in 1991) with that of the RSBI calculated directly from MV parameters. Methods: This was a prospective observational study involving patients who had been on MV for more than 24 h and were candidates for weaning. The RSBI was obtained by the same examiner using the two different methods (employing a spirometer and the parameters from the ventilator display) at random. In comparing the values obtained with the two methods, we used the Mann-Whitney test, Pearson's linear correlation test, and Bland-Altman plots. The performance of the methods was compared by evaluation of the areas under the ROC curves. Results: Of the 109 selected patients (60 males; mean age, 62 ± 20 years), 65 were successfully weaned, and 36 died. There were statistically significant differences between the two methods for respiratory rate, tidal volume, and RSBI (p < 0.001 for all). However, when the two methods were compared, the concordance and the intra-observer variation coefficient were 0.94 (0.92-0.96) and 11.16%, respectively. The area under the ROC curve was similar for both methods (0.81 ± 0.04 vs. 0.82 ± 0.04; p = 0.935), which is relevant in the context of this study. Conclusions: The satisfactory performance of the RSBI as a predictor of weaning success, regardless of the method employed, demonstrates the utility of the method using the mechanical ventilator.

Keywords: Respiration, artificial; Ventilator weaning; Spirometry.

Objective: To evaluate the accuracy of rapid molecular testing as a diagnostic tool and estimate the incidence of smear-positive pulmonary tuberculosis among the indigenous population. Methods: This is an epidemiological study based on secondary data. We calculated the incidence of smear-positive pulmonary tuberculosis between January 1st, 2011 and December 31, 2016, and the performance of bacilloscopy and rapid molecular testing in diagnosing pulmonary tuberculosis compared to sputum culture (standard test). Results: We included 4,048 cases of indigenous people with respiratory symptoms who provided sputum samples for analysis. Among them, 3.7%, 6.7%, and 3.7% had positive results for bacilloscopy, sputum culture, and rapid molecular testing, respectively. The mean incidence of pulmonary tuberculosis was 269.3/100 thousand inhabitants. Rapid molecular testing had 93.1% sensitivity and 98.2% specificity, compared to sputum culture. Bacilloscopy showed 55.1% sensitivity and 99.6% specificity. Conclusions: Rapid molecular testing can be useful in remote areas with limited resources and a high incidence of tuberculosis, such as indigenous villages in rural regions of Brazil. In addition, the main advantages of rapid molecular testing are its easy handling, fast results, and the possibility of detecting rifampicin resistance. Together, these attributes enable the early start of treatment, contributing to reduce the transmission in communities recognized as vulnerable to infection and disease.

Keywords: Tuberculosis; Molecular diagnostic testing; Diagnostic tests, routine; Indians, South American.

A significant percentage of pleural effusions remains without a diagnostic explanation. In such circumstances, the anatomical-pathological result of nonspecific chronic pleuritis should be revised. This is an important issue, not only for the pathologist, but mainly for the pneumologist, who usually makes the clinical-pathological correlation during the routine practice. Although the existence of established criteria is accepted, they are certainly subjective and make the communication by means of a common language difficult, mainly among pathologists. The authors recently studied 311 pleural biopsies with histo-pathological diagnoses of chronic nonspecific pleuritis. All specimens were reviewed and the histo-pathological parameters quantified by stereology. The patients were stratified according to the final diagnosis of their disease, including cases of chronic renal failure, vasculitis, pancreatitis, tuberculosis, cancer, and congestive cardiac failure, in this case considering the pleura as normal. This procedure allowed us to obtain a discriminating model, whose morphological subcriteria classified almost 90% of the nonspecific chronic pleuritis biopsies, according to their final clinical diagnoses, which included true nonspecific chronic pleuritis or tuberculosis pleuritis, paraneoplastic pleuritis, or even normal pleura. By adding to this model the biochemistry or differential cytology of the pleural liquid, its classificatory power reaches 99% of correctness. This study represents the result of the experience acquired over several years in the histo-pathological interpretation of pleural biopsies, based on the correlation between morphology and biochemistry and cytology of the pleural fluid.

Keywords: Biopsy, needle. Pleura/pathology. Pleura/cytology. Pleural effusion.

Objective: Bedside lung ultrasound (LUS) is a noninvasive, readily available imaging modality that can complement clinical evaluation. The Bedside Lung Ultrasound in Emergency (BLUE) protocol has demonstrated a high diagnostic accuracy in patients with acute respiratory failure (ARF). Recently, bedside LUS has been added to the medical training program of our ICU. The aim of this study was to investigate the accuracy of LUS based on the BLUE protocol, when performed by physicians who are not ultrasound experts, to guide the diagnosis of ARF. Methods: Over a one-year period, all spontaneously breathing adult patients consecutively admitted to the ICU for ARF were prospectively included. After training, 4 non-ultrasound experts performed LUS within 20 minutes of patient admission. They were blinded to patient medical history. LUS diagnosis was compared with the final clinical diagnosis made by the ICU team before patients were discharged from the ICU (gold standard). Results: Thirty-seven patients were included in the analysis (mean age, 73.2  14.7 years; APACHE II, 19.2  7.3). LUS diagnosis had a good agreement with the final diagnosis in 84% of patients (overall kappa, 0.81). The most common etiologies for ARF were pneumonia (n = 17) and hemodynamic lung edema (n = 15). The sensitivity and specificity of LUS as measured against the final diagnosis were, respectively, 88% and 90% for pneumonia and 86% and 87% for hemodynamic lung edema. Conclusions: LUS based on the BLUE protocol was reproducible by physicians who are not ultrasound experts and accurate for the diagnosis of pneumonia and hemodynamic lung edema.

Keywords: Ultrasonography, interventional; Respiratory insufficiency; Intensive care units.

Objective: Frequent readmissions for acute exacerbations of COPD (AECOPD) are an independent risk factor for increased mortality and use of health-care resources. Disease severity and C-reactive protein (CRP) level are validated predictors of long-term prognosis in such patients. This study investigated the utility of combining serum CRP level with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) exacerbation risk classification for predicting readmission for AECOPD. Methods: This was a prospective observational study of consecutive patients hospitalized for AECOPD at Peking University Third Hospital, in Beijing, China. We assessed patient age; gender; smoking status and history (pack-years); lung function; AECOPD frequency during the last year; quality of life; GOLD risk category (A-D; D indicating the greatest risk); and serum level of high-sensitivity CRP at discharge (hsCRP-D). Results: The final sample comprised 135 patients. Of those, 71 (52.6%) were readmitted at least once during the 12-month follow-up period. The median (interquartile) time to readmission was 78 days (42-178 days). Multivariate analysis revealed that serum hsCRP-D ≥ 3 mg/L and GOLD category D were independent predictors of readmission (hazard ratio = 3.486; 95% CI: 1.968-6.175; p < 0.001 and hazard ratio = 2.201; 95% CI: 1.342-3.610; p = 0.002, respectively). The ordering of the factor combinations by cumulative readmission risk, from highest to lowest, was as follows: hsCRP-D ≥ 3 mg/L and GOLD category D; hsCRP-D ≥ 3 mg/L and GOLD categories A-C; hsCRP-D < 3 mg/L and GOLD category D; hsCRP-D < 3 mg/L and GOLD categories A-C. Conclusions: Serum hsCRP-D and GOLD classification are independent predictors of readmission for AECOPD, and their predictive value increases when they are used in combination.

Keywords: Pulmonary disease, chronic obstructive/epidemiology; Acute disease; Acute-phase proteins; Hospitalization; Patient readmission; Inflammation.

Objective: To determine the absolute number of serum T lymphocytes and cytokine levels and the characteristics of patients with active pulmonary tuberculosis and to assess their effect on the immune status of these patients and their diagnostic and predictive value for tuberculosis. Methods: We included 1,069 patients with active tuberculosis, 51 patients with latent tuberculosis infection, and 600 health individuals. Absolute serum T-lymphocyte counts and cytokine levels were quantified. Results: T lymphocytes were significantly reduced in patients with active tuberculosis when compared with healthy individuals. The immune function of patients gradually decreased with age and was stronger in female patients than in males. Th1 cells expressed higher levels of cytokines than did Th2 cells. Logistic regression analysis showed that reduced CD3+ T, CD8+ T, and NK cell counts, as well as reduced IL-4 and IFN-? expression, were independent influencing factors for active tuberculosis. ROC analysis showed that the sensitivity and specificity of absolute CD3+ T and CD8+ T lymphocyte counts and combined factors were significantly higher than were those of IL-4 and IFN-? for diagnosing active tuberculosis. Conclusions: Serum T-lymphocyte counts and cytokine levels can assess the immune status of tuberculosis patients; they are also useful biomarkers for predicting and diagnosing tuberculosis.

Keywords: Lymphocytes; Cytokines; Tuberculosis; Immunity.

Objective: To investigate the diagnostic value of α-enolase (ENO1) and serum ENO1 autoantibody levels in lung cancer. Methods: Immunohistochemistry staining and ELISA were performed to detect ENO1 expression in lung tissue and serum ENO1 autoantibody levels, respectively. Results: The expression of ENO1 was higher in lung cancer tissues than in benign lung disease tissues (p < 0.001). The proportion of lung cancer samples expressing ENO1 was not significantly different among the various pathological classification groups. The proportion of samples expressing ENO1 was higher in lung cancer patients in stages I/II than in those in stages III/IV (χ2 = 5.445; p = 0.018). The expression of ENO1 in lung cancer tissues was not associated with age, gender, or smoking history. Serum ENO1 antibody levels were significantly higher in the lung cancer group than in the benign lung disease and control groups (p < 0.001). The differences among the pathological classification groups were not statistically significant. Serum ENO1 antibody levels were also in lung cancer patients in stages I/II than in those in stages III/IV (p < 0.01). Serum ENO1 antibody levels were not associated with age, gender, or smoking history in lung cancer patients. The ROC curve representing the diagnosis of lung cancer based on ENO1 antibody levels had an area under the curve of 0.806. Conclusions: Our results suggest that high levels of ENO1 are associated with the clinical stage of lung cancer and that ENO1 expression and its serum autoantibody levels show diagnostic value in lung cancer.

Keywords: Phosphopyruvate hydratase/analysis; Enzyme-linked immunosorbent assay; Immunohistochemistry; Lung neoplasms.

Objective: To evaluate the association between extubation failure and outcomes (clinical and functional) in patients with traumatic brain injury (TBI). Methods: A prospective cohort study involving 311 consecutive patients with TBI. The patients were divided into two groups according to extubation outcome: extubation success; and extubation failure (defined as reintubation within 48 h after extubation). A multivariate model was developed in order to determine whether extubation failure was an independent predictor of in-hospital mortality. Results: The mean age was 35.7 ± 13.8 years. Males accounted for 92.3%. The incidence of extubation failure was 13.8%. In-hospital mortality was 4.5% and 20.9% in successfully extubated patients and in those with extubation failure, respectively (p = 0.001). Tracheostomy was more common in the extubation failure group (55.8% vs. 1.9%; p < 0.001). The median length of hospital stay was significantly greater in the extubation failure group than in the extubation success group (44 days vs. 27 days; p = 0.002). Functional status at discharge was worse among the patients in the extubation failure group. The multivariate analysis showed that extubation failure was an independent predictor of in-hospital mortality (OR = 4.96; 95% CI, 1.86-13.22). Conclusions: In patients with TBI, extubation failure appears to lengthen hospital stays; to increase the frequency of tracheostomy and of pulmonary complications; to worsen functional outcomes; and to increase mortality.

Keywords: Brain injuries; Ventilator weaning; Intensive care units; Glasgow outcome scale.

We evaluated the diagnostic yield of fiberoptic bronchoscopy for the diagnosis of smear-negative pulmonary tuberculosis in patients treated at a referral hospital in Lima, Peru. Of the 611 patients who underwent the procedure, 140 (23%) were diagnosed with tuberculosis based on the analysis of BAL samples. Being young and being male were significantly associated with positive cultures. In addition, 287 patients underwent post-bronchoscopic sputum smear testing for AFB, the results of which increased the diagnostic yield by 22% over that obtained through the analysis of BAL samples alone. We conclude that the analysis of BAL samples and post-bronchoscopic sputum samples provides a high diagnostic yield in smear-negative patients suspected of having pulmonary tuberculosis.

Keywords: Tuberculosis, pulmonary/diagnosis; Bronchoscopy; Sputum.

Many conditions result in chronic interstitial lung disease (ILD), being classified as fibrosing ILDs, including idiopathic pulmonary fibrosis, connective tissue diseases, sarcoidosis, and fibrotic hypersensitivity pneumonitis. HRCT plays an important role in the clinical evaluation of fibrosing ILDs. Current treatment perspectives are encouraging and reinforce the need for HRCT scans of adequate technical quality for early detection of fibrosing ILD. Despite efforts in this regard, the significance and management of imaging findings of early interstitial lung abnormalities have yet to be clarified. After identification of CT findings consistent with fibrosing ILD, radiologists must be able to identify characteristic morphological patterns and, in some cases, features of specific clinical entities. In cases in which HRCT features are not sufficiently specific for a definitive diagnosis, HRCT can aid in selecting the best site for surgical lung biopsy. CT follow-up is useful for identifying progressive fibrosing ILDs and detecting complications unrelated to the underlying disease, including infections, acute exacerbations, and neoplasms. Automated quantification tools have clinical applicability and are likely to be available for use in imaging analysis in the near future. In addition, incorporation of CT evaluation into scoring systems based on clinical and functional parameters for staging fibrosing disease is likely to become valuable in determining prognosis. Knowledge of the clinical applications of CT evaluation is essential for specialists managing patients with fibrosing ILD and can have a positive impact on the clinical course of the disease.

Keywords: Tomography, X-ray computed; Diagnostic imaging; Pulmonary fibrosis.

Objective: Inspiratory fall in intrathoracic pressure during a spontaneous breathing trial (SBT) may precipitate cardiac dysfunction and acute pulmonary edema. We aimed to determine the relationship between radiological signs of pulmonary congestion prior to an SBT and weaning outcomes. Methods: This was a post hoc analysis of a prospective cohort study involving patients in an adult medical-surgical ICU. All enrolled individuals met the eligibility criteria for liberation from mechanical ventilation. Tracheostomized subjects were excluded. The primary endpoint was SBT failure, defined as the inability to tolerate a T-piece trial for 30-120 min. An attending radiologist applied a radiological score on interpretation of digital chest X-rays performed before the SBT. Results: A total of 170 T-piece trials were carried out; SBT failure occurred in 28 trials (16.4%), and 133 subjects (78.3%) were extubated at first attempt. Radiological scores were similar between SBT-failure and SBT-success groups (median [interquartile range] = 3 [2-4] points vs. 3 [2-4] points; p = 0.15), which, according to the score criteria, represented interstitial lung congestion. The analysis of ROC curves demonstrated poor accuracy (area under the curve = 0.58) of chest x-rays findings of congestion prior to the SBT for discriminating between SBT failure and SBT success. No correlation was found between fluid balance in the 48 h preceding the SBT and radiological score results (ρ = −0.13). Conclusions: Radiological findings of pulmonary congestion should not delay SBT indication, given that they did not predict weaning failure in the medical-surgical critically ill population. (ClinicalTrials.gov identifier: NCT02022839 [http://www.clinicaltrials.gov/])

Keywords: Radiography; Pulmonary edema; Ventilator weaning.

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.

Hypersensitivity pneumonitis (HP), or extrinsic allergic alveolitis, is an immunologically mediated disease resulting from the inhalation of organic substances that trigger an inflammatory response in the alveolar wall, bronchioles, and interstitium in susceptible individuals. Although HP is predominantly an occupational disease, seen in adulthood, cases in children have been described. The diagnosis of HP requires a high degree of suspicion. The treatment consists in avoiding contact with the antigen, and, in some cases, systemic corticosteroids might be necessary in order to prevent its progression to pulmonary fibrosis. We report the clinical cases of three children with a history of contact with birds and a family history of HP. All three patients presented with cough and dyspnea on exertion. The disease was diagnosed on the basis of the clinical history and ancillary diagnostic test results consistent with the diagnosis, including a predominance of lymphocytes (> 60%, CD8+ T lymphocytes in particular) in bronchoalveolar lavage fluid and a ground-glass pattern seen on HRCT of the chest. Early diagnosis is crucial in order to prevent HP from progressing to pulmonary fibrosis. Hereditary factors seem to influence the onset of the disease.

Keywords: Alveolitis, extrinsic allergic; Bronchoalveolar lavage; Glucocorticoids.

Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a new method for the diagnosis and staging of lung disease, and its use is increasing worldwide. It has been used as a means of diagnosing lung cancer in its initial stages, and there are data supporting its use for the diagnosis of benign lung disease. The aim of this study was to share our experience with EBUS-TBNA and discuss its diagnostic value. Methods: We retrospectively analyzed the results related to 159 patients who underwent EBUS-TBNA at our pulmonary medicine clinic between 2010 and 2013. We recorded the location and size of lymph nodes seen during EBUS. Lymph nodes that appeared to be affected on EBUS were sampled at least twice. We recorded the diagnostic results of EBUS-TBNA and (for cases in which EBUS-TBNA yielded an inconclusive diagnosis) the final diagnoses after further investigation and follow-up. Results: We evaluated 159 patients, of whom 89 (56%) were male and 70 (44%) were female. The mean age was 54.6 ± 14.2 years among the male patients and 51.9 ± 11.3 years among the female patients. Of the 159 patients evaluated, 115 (84%) were correctly diagnosed by EBUS. The diagnostic accuracy of EBUS-TBNA was 83% for benign granulomatous diseases and 77% for malignant diseases. Conclusions: The diagnostic value of EBUS-TBNA is also high for benign pathologies, such as sarcoidosis and tuberculosis. In patients with mediastinal disorders, the use of EBUS-TBNA should be encouraged, primarily because it markedly reduces the need for mediastinoscopy.

Keywords: Sarcoidosis; Tuberculosis, pulmonary; Lung neoplasms; Bronchoscopy; Mediastinoscopy; Endosonography.

Objective: To evaluate the capacity of the criteria described in Complementary Directive SAS/MS 12, issued on November 12, 2002, to identify patients with severe asthma, describing and comparing clinical, functional and treatment data of such patients. Methods: This was a nested case-control study using a structured database for adult asthma outpatients. We defined cases as asthma patients who met the inclusion criteria described in the directive, defining controls as those who did not. We collected and compared data related to the following: demographic characteristics; history of asthma; medications in use; comorbidities; history of tobacco use; number of exacerbations within the last 12 months, asthma-related hospitalizations and intensive care unit admissions within the last 12 months; spirometry; and sputum cytology. Results: The case and control groups consisted of 29 and 31 patients, respectively. The number of asthma exacerbations and emergency room visits within the last 12 months, as well as the number of patients that received at least one pulse of oral corticosteroids, was significantly higher in the case group than in the control group. In addition, prebronchodilator FVC was lower among the cases than among the controls. Furthermore, cytology revealed that eosinophil counts were significantly higher in the induced sputum of cases than in that of controls. Conclusions: The criteria described in the directive are suited to stratifying patients with severe asthma.

Keywords: Asthma; Budesonide; Combined modality therapy.

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.

Tuberculosis is one of the major infectious diseases in developing countries, and the length of time for which the chain of transmission is maintained has been implicated as a major factor in the perpetuation of the disease. In this context, regulatory agencies in such countries have approved new diagnostic tools, which have been almost immediately incorporated into the national tuberculosis control programs. Health interventions have been increasingly investigated in clinical trials, including explanatory trials (in order to evaluate the beneficial effects of such interventions) and pragmatic trials (in order to aid in the decision-making process). We argue that the evaluation of new diagnostic techniques for the detection of tuberculosis should not escape this same logic of evaluation.

Keywords: Tuberculosis/diagnosis; Tuberculosis/prevention & control; Controlled clinical trial as topic.