Objective: To compare patients with and without previous lung disease, in terms of the spirometry results after they had been treated for pulmonary tuberculosis (PTB) and cured, as well as to analyze risk factors related to functional severity. Methods: This was a cross-sectional, multicenter study conducted at four referral centers in Brazil. Patients were divided into two groups: those with a history of lung disease or smoking (LDS+ group); and those with no such history (LDS− group). Patients underwent spirometry (at least six months after being cured). Sociodemographic and clinical data were collected. Results: A total of 378 patients were included: 174 (46.1%) in the LDS+ group and 204 (53.9%) in the LDS− group. In the sample as a whole, 238 patients (62.7%) had spirometric changes. In the LDS+ group, there was a predominance of obstructive lung disease (in 33.3%), whereas restrictive lung disease predominated in the LDS− group (in 24.7%). Radiological changes were less common in the LDS− group than in the LDS+ group (p < 0.01), as were functional changes (p < 0.05). However, of the 140 (79.1%) LDS− group patients with a normal or minimally altered chest X-ray, 76 (54%) had functional changes (p < 0.01). The risk factors associated with functional severity in the LDS− group were degree of dyspnea (p = 0.03) and moderate or severe radiological changes (p = 0.01). Conclusions: Impaired pulmonary function is common after treatment for PTB, regardless of the history of lung disease or smoking. Spirometry should be suggested for patients who develop moderate/severe dyspnea or relevant radiological changes after treatment for PTB.

Keywords: Tuberculosis, pulmonary; Respiratory function tests; Airway obstruction/complications.

Objective: To compare diaphragmatic mobility, lung function, and respiratory muscle strength between COPD patients with and without thoracic hyperkyphosis; to determine the relationship of thoracic kyphosis angle with diaphragmatic mobility, lung function, and respiratory muscle strength in COPD patients; and to compare diaphragmatic mobility and thoracic kyphosis between male and female patients with COPD. Methods: Participants underwent anthropometry, spirometry, thoracic kyphosis measurement, and evaluation of diaphragmatic mobility. Results: A total of 34 patients with COPD participated in the study. Diaphragmatic mobility was significantly lower in the group of COPD patients with thoracic hyperkyphosis than in that of those without it (p = 0.002). There were no statistically significant differences between the two groups of COPD patients regarding lung function or respiratory muscle strength variables. There was a significant negative correlation between thoracic kyphosis angle and diaphragmatic mobility (r = −0.47; p = 0.005). In the sample as a whole, there were statistically significant differences between males and females regarding body weight (p = 0.011), height (p < 0.001), and thoracic kyphosis angle (p = 0.036); however, there were no significant differences in diaphragmatic mobility between males and females (p = 0.210). Conclusions: Diaphragmatic mobility is lower in COPD patients with thoracic hyperkyphosis than in those without it. There is a negative correlation between thoracic kyphosis angle and diaphragmatic mobility. In comparison with male patients with COPD, female patients with COPD have a significantly increased thoracic kyphosis angle.

Keywords: Pulmonary disease, chronic obstructive; Kyphosis; Diaphragm.

Objective: To compare the efficacy, safety, and tolerability of azithromycin and amoxicillin in the treatment of patients with infectious exacerbation of chronic obstructive pulmonary disease. Methods: This study was conducted at six medical centers across Brazil and included 109 patients from 33 to 82 years of age. Of those, 102 were randomized to receive either azithromycin (500 mg/day for three days, n = 49) or amoxicillin (500 mg every eight hours for ten days, n = 53). The patients were evaluated at the study outset, on day ten, and at one month. Based on the clinical evaluation of the signs and symptoms present on day ten and at one month, the outcomes were classified as cure, improvement, or treatment failure. The microbiological evaluation was made through the culture of sputum samples that were considered appropriate samples only after leukocyte counts and Gram staining. Secondary efficacy evaluations were made in order to analyze symptoms (cough, dyspnea, and expectoration) and pulmonary function. Results: There were no differences between the groups treated with azithromycin or amoxicillin in terms of the percentages of cases in which the outcomes were classified as cure or improvement: 85% vs. 78% (p = 0.368) on day ten; and 83% vs. 78% (p = 0.571) at one month. Similarly, there were no significant differences between the two groups in the secondary efficacy variables or the incidence of adverse effects. Conclusion: Azithromycin and amoxicillin present similar efficacy and tolerability in the treatment of acute exacerbation of chronic obstructive pulmonary disease.

Keywords: Amoxicillin/therapeutic use; Azithromycin/therapeutic use; Bronchitis, chronic/drug therapy;

Objective: Because SARS-CoV-2 infection can severely affect the lungs and persistent functional changes can occur after severe disease, we aimed to determine lung function parameters of COVID-19 patients at 45 days after hospital discharge and compare changes according to the severity of the disease. Methods: This was a prospective descriptive analytical multicenter study. The participants were allocated into three groups: ward admission (WA) group; ICU admission not on mechanical ventilation (ICU/MV-) group; and ICU admission on MV (ICU/MV+) group. Lung volumes, DLco, MIP, MEP, and six-minute walk distance (6MWD) were measured 45 days after discharge. Results: The sample comprised 242 patients (mean age = 59.4 ± 14.8 years; 52.1% of males), and 232 (96%) had altered lung function. In the total cohort, restrictive disorder was observed in 96%, as well as reductions in DLco (in 21.2% of the patients), FEV1/FVC (in 39.7%), and PEmax (in 95.8%), with no differences between the groups. Comparing the groups, the ICU/MV+ group had reduced DLco in 50% of the patients (p < 0.001) and a lower mean 6MWD % of the predicted value (p = 0.013). Oxygen desaturation in the six-minute walk test was observed in 32.3% of the cohort and was less frequent in the IE group. Conclusions: This is the first South American study involving severe COVID-19 survivors whose lung function was assessed 45 days after hospital discharge. Changes were frequent, especially in those on MV, which highlights the importance of lung function evaluation after severe COVID-19.

Keywords: COVID-19; Respiratory function tests; Pulmonary diffusing capacity; Virus disease; SARS-CoV-2.

Introduction: Spirometry and analysis of blood gases data have been extensively used to assess ventilatory limitation and prognosis of COPD patients. However, functional physical tests, such as the six-minute walk test (6wt) have been used for the dynamic assessment of COPD patients. Objective: To determine correlations between respiratory function test data and the six-minute walk test in COPD patients. Patients and methods: 45 patients were submitted to clinical history survey and complete physical examination performed by the medical staff of the Pneumology Department of the Brasilia University Hospital, followed by spirometry, analysis of arterial blood gases, maximal respiratory pressures data, and the six-minute walk test. Results: Concerning the spirometric, analysis of blood gases and maximal respiratory pressures data, statistically significant positive correlations (p < 0.05) between FEV1, PaO2, SpO2, MEP and the six-minute walk test were obtained. Conclusions: For the studied group, the six minute walk test has significant correlation with FEV1, PaO2, SpO2 and MEP, and can be used as an alternative functional assessment of COPD patients.

Objective: To study correlations among pulmonary function, chest radiology and clinical status in cystic fibrosis. Methods: A retrospective cross-sectional study was performed to evaluate chest X-rays and clinical charts of patients treated at the Hospital de Clínicas de Porto Alegre. Spirometry findings, Shwachman-Kulczycki (S-K) scores and Brasfield scores were analyzed. Results: The final sample consisted of 40 patients (mean age 9.72 ± 3.27). The following mean S-K scores were obtained: total, 80.87 ± 10.24; general activity, 24.75 ± 1.1; physical examination, 18.87 ± 4.59; nutrition, 21.87 ± 4.18; radiology, 15.37 ± 5.23. The mean Brasfield score was 18.2 ± 4. The pulmonary function test results, in percentage of predicted, were as follows: forced vital capacity (FVC), 82.99 ± 14.36%; forced expiratory volume in one second (FEV1), 83.62 ± 18.26%; and forced expiratory flow between 25 and 75% of FVC (FEF25-75), 74.63 ± 2.53%. The S-K score correlated moderately with FVC, whereas it correlated strongly with FEV1 and FEF25-75. The Brasfield score correlated strongly with the S-K total and radiology score, whereas it correlated moderately with pulmonary function. Physical examination correlated moderately with FVC, FEV1 and FEF25-75; as did nutrition with FEF25-75; and radiology with FEV1 and FEF25-75. General activity was the domain that had the greatest influence on the total S-K score. Conclusions: These two scoring systems are complementary, correlating with each other, as well as with pulmonary function tests. The radiology domain of the S-K scoring system is a good alternative to the Brasfield score.

Keywords: Cystic fibrosis; Spirometry; Lung/radiography.

The objective of this study was to review the literature on bronchoalveolar lavage fluid cell profiles in healthy children and adolescents, as well as on the use of BAL as a diagnostic and follow-up tool for lung disease patients in this age bracket. To that end, we used the Medline database, compiling studies published between 1989 and 2009 employing the following MeSH descriptors (with Boolean operators) as search terms: bronchoalveolar lavage AND cytology OR cell AND child. In healthy children, the cell profile includes alveolar macrophages (> 80%), lymphocytes (approximately 10%), neutrophils (approximately 2%) and eosinophils (< 1%). The profile varies depending on the disease under study. The number of neutrophils is greater in wheezing children, especially in non-atopic children, as well as in those with pulmonary infectious and inflammatory profiles, including cystic fibrosis and interstitial lung disease. Eosinophil counts are elevated in children/adolescents with asthma and can reach high levels in those with allergic bronchopulmonary aspergillosis or eosinophilic syndromes. In a heterogenous group of diseases, the number of lymphocytes can increase. Evaluation of the BAL fluid cell profile, when used in conjunction with clinical and imaging findings, has proven to be an essential tool in the investigation of various lung diseases. Less invasive than transbronchial and open lung biopsies, BAL has great clinical value. Further studies adopting standard international protocols should be carried out. Such studies should involve various age groups and settings in order to obtain reference values for BAL fluid cell profiles, which are necessary for a more accurate interpretation of findings in children and adolescents with lung diseases.

Keywords: Bronchoalveolar lavage; Bronchoalveolar lavage fluid/cytology; Child; Adolescent.

Objective: To identify factors that lead to a positive oxygenation response and predictive factors of mortality after prone positioning. Methods: This was a retrospective, multicenter, cohort study involving seven hospitals in Brazil. Inclusion criteria were being > 18 years of age with a suspected or confirmed diagnosis of COVID-19, being on invasive mechanical ventilation, having a PaO2/FIO2 ratio < 150 mmHg, and being submitted to prone positioning. After the first prone positioning session, a 20 mmHg improvement in the PaO2/FIO2 ratio was defined as a positive response. Results: The study involved 574 patients, 412 (72%) of whom responded positively to the first prone positioning session. Multiple logistic regression showed that responders had lower Simplified Acute Physiology Score III (SAPS III)/SOFA scores and lower D-dimer levels (p = 0.01; p = 0.04; and p = 0.04, respectively). It was suggested that initial SAPS III and initial PaO2/FIO2 were predictors of oxygenation response. The mortality rate was 69.3%. Increased risk of mortality was associated with age (OR = 1.04 [95 CI: 1.01-1.06]), time to first prone positioning session (OR = 1.18 [95 CI: 1.06-1.31]), number of sessions (OR = 1.31 [95% CI: 1.00-1.72]), proportion of pulmonary impairment (OR = 1.55 [95% CI: 1.02-2.35]), and immunosuppression (OR = 3.83 [95% CI: 1.35-10.86]). Conclusions: Our results show that most patients in our sample had a positive oxygenation response after the first prone positioning session. However, the mortality rate was high, probably due to the health status and the number of comorbidities of the patients, as well as the severity of their disease. Our results also suggest that SAPS III and the initial PaO2/FIO2 predict the oxygenation response; in addition, age, time to first prone positioning, number of sessions, pulmonary impairment, and immunosuppression can predict mortality.

Keywords: Respiratory distress syndrome; Coronavirus infections; Pulmonary medicine; COVID-19; Prone position; SARS-CoV-2.

Objective: To describe and analyze clinical symptoms and spirometric alterations of patients with chronic obstructive pulmonary disease (COPD) and history of exposure to wood and tobacco smoke. Methods: We retrospectively evaluated data related to 170 patients distributed into 3 groups: 34 exposed only to wood smoke, 59 patients exposed only to tobacco smoke and 77 patients exposed to both. Results: The groups did not differ significantly in terms of age (p = 0.225) or degree of exposure, considering each type of exposure in isolation or in combination (p = 0.164 and p = 0.220, respectively). Females predominated in the group exposed to wood smoke. There were no differences among the groups regarding respiratory symptoms (p > 0.05), and moderate dyspnea predominated in the three groups (p = 0.141). The group exposed to wood smoke presented higher percentages of forced expiratory volume in one second/forced vital capacity ratio and of forced expiratory volume in one second (p < 0.05). Positive results on bronchodilator testing occurred more frequently in the group exposed to tobacco smoke. The percentage of severe and extremely severe obstruction was significantly higher in the group exposed to tobacco smoke (44.1%) than in that exposed to wood smoke (11.8%; p = 0.006). Conclusions: Respiratory symptoms and pulmonary function alterations consistent with COPD were observed in the groups of patients exposed to wood smoke. However, those alterations were not as significant as the alterations observed in the groups exposed to tobacco smoke. This study emphasizes the importance of prospective studies in evaluating the risk of wood-smoke-related COPD in Brazil, as well as the need for preventive measures in this area.

Keywords: Pulmonary disease, chronic obstructive; Smoking; Air pollution, indoor; Smoke.

Objective: To analyze the association of dysglycemia with clinical, laboratory, and radiographic characteristics of patients with pulmonary tuberculosis (PTB), as well as with their tuberculo-sis treatment outcomes. Methods: This was a longitudinal study involving 140 patients diag-nosed with PTB (positive cultures for Mycobacterium tuberculosis or positive Xpert MTB/RIF results from sputum samples). Patients were evaluated at diagnosis (M0), after completing the second month of treatment (M2), and at the end of treatment (MEND). At M0, the pati-ents were classified into three groups: normoglycemia+PTB (NGTB); pre-diabetes melli-tus+PTB (PDMTB), and diabetes mellitus+PTB (DMTB), in accordance with glycated hemoglo-bin levels (< 5.7%, 5.7%-6.4%, and = 6.5%, respectively). Treatment outcomes were classified as favorable (cure or treatment completion) and unfavorable (death, loss to follow-up, or treatment failure). Results: In our sample, 76 patients (61.4%) had dysglycemia, 20 of whom (14.3%) had DM at M0. The patients with dysglycemia, in comparison with those in the NGTB group, more frequently presented with positive sputum smear microscopy (94.2% vs. 75.9%; p = 0.003); cavities (80.2% vs. 63.0%; p = 0.03); bilateral lesions (67.4% vs. 46.0%; p = 0.02); and higher median of affected thirds of the lungs (3.0 vs. 2.0; p = 0.03) on chest radiography. No significant differences regarding outcomes were found among the groups, but tuberculosis lethality was higher in the DMTB group than in the PDMTB and NGTB groups (20% vs. 2.2%). Conclusions: PTB patients with dysglycemia had laboratory and radiographic manifestations indicative of more advanced disease, and the risk of death was higher in the DMTB group. These findings reinforce the recommendation for early screening for DM in patients with newly diagnosed tuberculosis in order to reduce the risk of death during treatment.

Keywords: Tuberculosis/diagnosis; Tuberculosis/diagnostic imaging; Tuberculosis/therapy; Diabetes mellitus; Treatment outcome.

Objective: To evaluate lung function in a cohort of patients with a history of pulmonary tuberculosis in Brazil, as well as to evaluate the decline in lung function over time and compare it with that observed in similar cohorts in Mexico and Italy. Methods: The three cohorts were compared in terms of age, smoking status, pulmonary function test results, six-minute walk test results, and arterial blood gas results. In the Brazilian cohort, pulmonary function test results, six-minute walk test results, and arterial blood gas results right after the end of tuberculosis treatment were compared with those obtained at the end of the follow-up period. Results: The three cohorts were very different regarding pulmonary function test results. The most common ventilatory patterns in the Brazilian, Italian, and Mexican cohorts were an obstructive pattern, a mixed pattern, and a normal pattern (in 58 patients [50.9%], in 18 patients [41.9%], and in 26 patients [44.1%], respectively). Only 2 multidrug-resistant tuberculosis cases were included in the Brazilian cohort, whereas, in the Mexican cohort, 27 cases were included (45.8%). Mean PaO2 and mean SaO2 were lower in the Mexican cohort than in the Brazilian cohort (p < 0.0001 and p < 0.002 for PaO2 and SaO2, respectively). In the Brazilian cohort, almost all functional parameters deteriorated over time. Conclusions: This study reinforces the importance of early and effective treatment of drug-susceptible tuberculosis patients, because multidrug-resistant tuberculosis increases lung damage. When patients complete their tuberculosis treatment, they should be evaluated as early as possible, and, if post-tuberculosis lung disease is diagnosed, they should be managed and offered pulmonary rehabilitation because there is evidence that it is effective in these patients.

Keywords: Tuberculosis; Tuberculosis, multidrug-resistant; Spirometry; Rehabilitation.

Aim: To evaluate the performance of an SHM scheme (streptomycin, isoniazid, and ethambutol) in an outpatient clinic routine treatment for tuberculosis. Method: Seventy-eight patients with tuberculosis whose prior treatment with the RHZ scheme (six months of rifampicin, isoniazid, and pyrazinamide) had to be discontinued due to adverse effects, or who could not receive the RHZ scheme due to high risk for liver toxicity, were treated in the outpatient clinic with the 12 month SHM scheme from 1986 to 1994, in the city of Porto Alegre, Rio Grande do Sul, Brazil. Results: Three patients (3.8%) required a scheme change due to toxicity. In the remaining 75 patients, 58 (77.3%) were cured, eight (10.7%) withdrew, five (6.7%) presented failure, and four (5.3%) died. Theoretical cure rate, which is the percent of cure of patients who regularly followed the treatment, was 95.3%. Adverse reactions were seen in 32 patients (41%), the most frequent being vestibular damage in 18 patients (23.1%). Results were compared to those obtained in the same outpatient clinic with the 12 month RHM scheme (rifampicin, isoniazid, and ethambutol), and with the six month RHZ scheme. Conclusion: The SHM scheme may be recommended as an alternative for the treatment of tuberculosis whenever the RHZ scheme cannot be indicated.

Objective: To evaluate the prevalence of pulmonary function abnormalities and to investigate the factors affecting lung function in patients treated for pulmonary tuberculosis. Methods: A total of 214 consecutive patients (132 men and 82 women; 20-82 years of age), treated for pulmonary tuberculosis and followed at a local dispensary, underwent spirometry and plethysmography at least one year after treatment. Results: Pulmonary impairment was present in 102 (47.7%) of the 214 patients evaluated. The most common functional alteration was obstructive lung disease (seen in 34.6%). Of the 214 patients, 60 (28.0%) showed reduced pulmonary function (FEV1 below the lower limit of normal). Risk factors for reduced pulmonary function were having had culture-positive pulmonary tuberculosis in the past, being over 50 years of age, having recurrent tuberculosis, and having a lower level of education. Conclusions: Nearly half of all tuberculosis patients evolve to impaired pulmonary function. That underscores the need for pulmonary function testing after the end of treatment.

Keywords: Respiratory function tests; Tuberculosis, pulmonary; Spirometry; Lung diseases, obstructive.

Objective: To evaluate the diagnostic accuracy of bronchoscopy in patients with clinical or radiological suspicion of tuberculosis who were unable to produce sputum or with negative sputum smear microscopy results. Methods: A prospective cross-sectional study involving 286 patients under clinical or radiological suspicion of having pulmonary tuberculosis and submitted to bronchoscopy-BAL and transbronchial biopsy (TBB). The BAL specimens were submitted to direct testing and culture for AFB and fungi, whereas the TBB specimens were submitted to histopathological examination. Results: Of the 286 patients studied, 225 (79%) were diagnosed on the basis of bronchoscopic findings, as follows: pulmonary tuberculosis, in 127 (44%); nonspecific chronic inflammation, in 51 (18%); pneumocystis, fungal infections, or nocardiosis, in 20 (7%); bronchiolitis obliterans organizing pneumonia, alveolites, or pneumoconiosis, in 14 (5%); lung or metastatic neoplasms, in 7 (2%); and nontuberculous mycobacterium infections, in 6 (2%). For the diagnosis of tuberculosis, BAL showed a sensitivity and a specificity of 60% and 100%, respectively. Adding the TBB findings significantly increased this sensitivity (to 84%), as did adding the post-bronchoscopy sputum smear microscopy results (total sensitivity, 94%). Minor post-procedure complications occurred in 5.6% of the cases. Conclusions: Bronchoscopy is a reliable method for the diagnosis of pulmonary tuberculosis, with low complication rates. The combination of TBB and BAL increases the sensitivity of the method and facilitates the differential diagnosis with other diseases.

Keywords: Bronchoscopy; Tuberculosis, pulmonary; Sputum; Bronchoalveolar lavage; Biopsy.

Background: Pulmonary hypertension secondary to chronic thromboembolism is a severe and debilitating disease and has been associated with high mortality. Pulmonary thromboendarterectomy is the treatment of choice. Objective: To evaluate the impact of pulmonary thromboendarterectomy on the quality of life of patients with pulmonary hypertension secondary to chronic thromboembolism using the SF-36 Health Survey. Method: The SF-36 Health Survey questionnaire was administered to 13 patients prior to and at least 3 months following thromboendarterectomy. Results: Of the 13 patients studied, 7 were female and 6 were male. Mean age was 45.7 ± 18.3. All were submitted to thromboendarterectomy. After surgery, all SF-36 domains, with the exception of the "mental health" domain, improved. Conclusion: Pulmonary thromboendarterectomy provides significant improvement in patient quality of life.

Keywords: Key words: Hypertension pulmonary. Pulmonary embolism. Endarterectomy/methods. Quality of life.

Objective: To determine the association between smoking and pulmonary tuberculosis treatment failure. Methods: This was a case-control study conducted at the Brazilian Institute for Tuberculosis Research in the city of Salvador, Brazil, between 2007 and 2015. We evaluated 284 patients treated for pulmonary tuberculosis, comparing 50 cases of treatment failure with 234 control cases in which the final outcome was cure. Results: Treatment failure was attributed to smoking and age rather than to gender, income, level of education, alcohol consumption, or marital status. Therefore, even after adjustment for age, the risk of treatment failure was 2.1 times (95% CI: 1.1-4.1) higher among the patients with a history of smoking. In addition, being over 50 years of age was found to increase the likelihood of treatment failure by 2.8 times (95% CI: 1.4-6.0). Conclusions: Smoking and aging are both associated with pulmonary tuberculosis treatment failure. Therefore, as part of a tuberculosis control program, health personnel should be prepared to offer strategies to promote smoking cessation and should be more careful with older patients.

Keywords: Tobacco use disorder; Tuberculosis; Treatment failure.

Objective: To study the effects of nocturnal hypoxemia in patients with chronic obstructive pulmonary disease without obstructive sleep apnea syndrome. Methods: We studied 21 patients-10 desaturators and 11 nondesaturators-submitted to arterial blood gas analysis, polysomnography, spirometry, cardiopulmonary exercise testing (cycle ergometer), and hand-grip dynamometry, as well as measurements of maximal inspiratory pressure, maximal expiratory pressure, and C-reactive protein (CRP) levels. Patients with arterial oxygen tension > 60 mmHg were included; those with an apnea-hypopnea index > 5 events/hour of sleep were excluded. Maximal oxygen uptake, maximal power, systolic blood pressure, diastolic blood pressure (DBP), and maximal heart rate were measured during exercise in order to detect hemodynamic alterations. Patients presenting CRP levels above 3 mg/L were considered CRP-positive. Results: Minimal peripheral oxygen saturation during sleep was significantly higher among nondesaturators (p = 0.03). More desaturators presented CRP > 3 mg/L (p < 0.05). No differences were observed in terms of any variables, However, mean peripheral oxygen saturation during sleep correlated with DBP and maximal inspiratory pressure (p < 0.001 and p = 0.001, respectively). Conclusions: Although nocturnal hypoxemia does not reduce exercise capacity or hand-grip strength in patients with mild/moderate COPD, its effect on maximal exercise DBP seems to depend on the degree of hypoxemia. In addition, there is a positive relationship between maximal inspiratory pressure and mean peripheral oxygen saturation during sleep, as well as evidence of pronounced inflammatory activation in patients with nocturnal hypoxemia.

Keywords: Pulmonary disease, chronic obstructive; Exercise test; Anoxia; Respiratory function tests.

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.

Objective: Many patients with proportional reductions in FVC and FEV1 on spirometry show no reduction in TLC. The aim of this study was to evaluate the role that measuring lung volumes and airway resistance plays in the correct classification of patients with a possible restrictive pattern on spirometry. Methods: This was a prospective study involving adults with reduced FVC and FEV1, as well as an FEV1/FV(C) ratio within the predicted range. Restrictive lung disease (RLD) was characterized by TLC below the 5th percentile, as determined by plethysmography. Obstructive lung disease (OLD) was characterized by high specific airway resistance, significant changes in post-bronchodilator FEV1, or an FEF25-75% < 50% of predicted, together with a high RV/TLC ratio. Nonspecific lung disease (NLD) was characterized by TLC within the predicted range and no obstruction. Combined lung disease (CLD) was characterized by reduced TLC and findings indicative of airflow obstruction. Clinical diagnoses were based on clinical suspicion, a respiratory questionnaire, and the review of tests of interest. Results: We included 300 patients in the study, of whom 108 (36%) were diagnosed with RLD. In addition, 120 (40%) and 72 (24%) were diagnosed with OLD/CLD and NLD, respectively. Among the latter, 24 (33%) were clinically diagnosed with OLD. In this sample, 151 patients (50.3%) were obese, and obesity was associated with all patterns of lung disease. Conclusions: Measuring lung volumes and airway resistance is often necessary in order to provide an appropriate characterization of the pattern of lung disease in patients presenting with a spirometry pattern suggestive of restriction. Airflow obstruction is common in such cases.

Keywords: Spirometry; Airway resistance; Lung volume measurements.