Silicosis, the most prevalent of the pneumoconioses, is caused by inhalation of crystalline silica particles. Silica-exposed workers, with or without silicosis, are at increased risk for tuberculosis and nontuberculous mycobacteria-related diseases. The risk of a patient with silicosis developing tuberculosis is higher (2.8 to 39 times higher, depending on the severity of the silicosis) than that found for healthy controls. Various regimens for tuberculosis chemoprophylaxis in patients with silicosis have been studied, all of which present similar efficacy and overall risk reduction to about one half of that obtained with placebo. Long-term regimens have potential side effects (particularly hepatotoxicity). In addition, the use of such regimens can jeopardize adherence to treatment. The current guidelines recommend that tuberculin skin tests be performed, and, if positive, that chemoprophylaxis be instituted. There are several possible regimens, varying in terms of the drugs prescribed, as well as in terms of treatment duration. We recommend the use of isoniazid at 300 mg/day (or 10 mg/kg/day) for six months for patients with silicosis, as well as for healthy patients with periods of exposure to silica longer than 10 years and strongly positive tuberculin skin test results (induration ≥ 10 mm). Nevertheless, further studies are necessary so that indications, drugs, doses and duration of chemoprophylaxis regimens can be more properly defined.

Keywords: Silicosis; Tuberculosis; Diagnostic techniques and procedures; Chemoprevention.

Tuberculosis and cryptococcosis are infectious diseases that can result in the formation of single or multiple nodules in immunocompetent patients. Exposure to silica is known to raise the risk of infection with Mycobacterium tuberculosis. We report the case of an elderly man with no history of opportunistic infections and no clinical evidence of immunodeficiency but with a six-month history of dry cough and nocturnal wheezing. A chest X-ray revealed a mass measuring 5.0 × 3.5 cm in the right upper lobe. The diagnostic approach of the mass revealed tuberculosis. The histopathological analysis of the surrounding parenchyma reveled silicosis and cryptococcosis. Cryptococcosis was also found in masses identified in the mediastinal lymph nodes. The surgical approach was indicated because of the degree of pleuropulmonary involvement, the inconclusive results obtained with the invasive and noninvasive methods applied, and the possibility of malignancy. This case illustrates the difficulty inherent to the assessment of infectious or inflammatory pulmonary pseudotumors, the differential diagnosis of which occasionally requires a radical surgical approach. Despite the presence of respiratory symptoms for six months, the first chest X-ray was performed only at the end of that period. We discuss the possible pathogenic mechanisms that might have led to the combination of three types of granulomatous lesions in the same lobe, and we emphasize the need for greater awareness of atypical presentations of pulmonary tuberculosis.

Objective: Although ventilator-associated pneumonia (VAP) is a major cause of nosocomial infection, its role in the prognosis of patients remains undefined. The objective of this study was to evaluate the impact of VAP on the clinical evolution of patients. Methods: This was a prospective cohort study involving 233 patients on mechanical ventilation (VAP group, n = 64; control group, n = 169). Primary outcomes were time on mechanical ventilation (TMV), time in ICU (TICU), overall length of hospital stay (LHS) and in-ICU mortality. Secondary outcomes were in-hospital mortality, microbiological profile, prior use of antibiotics and risk factors for VAP acquisition. Results: Control and VAP group outcomes were, respectively, as follows: median TMV (days), 9 (interquartile range [IQR]: 5-15) and 23 (IQR: 15-37; p < 0.0001); median TICU (days), 12 (IQR: 8-21) and 27 (IQR: 17-42; p < 0.0001); median LHS (days), 33 (IQR: 18-64) and 46 (IQR: 25-90; p = 0.05); and in-ICU mortality, 38% (95% CI: 31-45) and 55% (95% CI: 42-67; p = 0.02). VAP was a predictor of in-ICU mortality (OR = 3.40; 95% CI: 1.54‑7.48). TMV (OR = 2.27; 95% CI: 1.05-4.87) and prior use of antibiotics (OR = 1.07; 95% CI: 1.04-1.10) were risk factors for VAP. VAP did not affect in-hospital mortality. Acinetobacter spp. was the most common isolate (28%). Inappropriate empirical antibiotic therapy was administered in 48% of cases. Conclusions: In this study, there was a high incidence of infection with resistant bacteria and inappropriate initial antibiotic therapy. Long TMV and prior use of antibiotics are risk factors for VAP.

Keywords: Pneumonia, ventilator-associated; Cross infection; Intensive care units; Hospital mortality; Risk factors.

Tuberculosis remains a serious social and public health problem, affecting millions of people annually. The bacille Calmette-Guerin (BCG) vaccine, used prophylactically, does not impede the progression of the disease, which usually manifests as decreased cellular immunity. Early diagnosis, together with polychemotherapy, can control the dissemination of the tuberculosis infection. The current diagnostic methods present certain problems. Such problems include the low sensitivity of sputum smear microscopy, the fact that performing microbiological cultures is quite time-consuming, and the low specificity of the skin test with the purified protein derivative of Mycobacterium tuberculosis. New diagnostic methods, which use specific antigens such as the early secreted antigenic target 6-kDa and culture filtrate protein 10‑kDa, are being evaluated. The genes that encode these antigens are located in the DNA region of difference 1 of M. tuberculosis, M. africanum and M. bovis. However, they are absent from the M. bovis (BCG) and from most environmental mycobacteria. Diagnostic methods such as QuantiFERON-TB® and T SPOT.TB®, which are based on the production of interferon-gamma by T lymphocytes, in response to those antigens, are being tested and have been found to outstrip the purified protein derivative skin test in the following characteristics: greater sensitivity; lower cross-reactivity due to BCG vaccination or infection with environmental mycobacteria; and execution time. The introduction of diagnostic methods that are more specific and sensitive, together with gaining a better understanding of the molecular and cellular mechanisms that regulate the parasite-host interaction, can increase the efficiency of strategies devised to combat tuberculosis.

Keywords: Tuberculosis; Mycobacterium tuberculosis; Diagnosis; Antigens, bacterial/ESAT-6 protein; Immunity.

The epidemiological relevance of tuberculosis is directly related to the socioeconomic profile of a given country. Vulnerability to tuberculosis is influenced by biological factors (e.g., malnutrition, HIV infection, and age) and social factors (e.g., unhealthy housing, high population density, inappropriate working conditions, and lack of access to health services). In many cases, multiple vulnerabilities occur in conjunction. We propose here a reflection on tuberculosis from the point of view of the social determinants of health, as well as the costs associated with its diagnosis and treatment in Brazil, based not only on data in the international literature but also on evidence related to the national context. Given the magnitude of tuberculosis as a socially mediated disease, there is an evident need for greater involvement of health professionals and of the scientific community to implement relevant operational and research measures to understand the social conditions influencing the health-illness continuum for tuberculosis patients. Although the recent economic crisis in Brazil has contributed to increased mortality from all causes, including tuberculosis, health and social protection expenditures have mitigated detrimental health effects. The evidence presented here underscores the importance of public social protection policies for minimizing the effects of tuberculosis indicators, with the aim of eliminating tuberculosis in Brazil.

Keywords: Tuberculosis; Social determinants of health; Cost of illness; Costs and cost analysis.

Objective: The present study aimed to describe the clinical forms and the time taken to diagnose new tuberculosis cases and to statistically analyze the isolated and combined forms of the disease in children and adolescents treated at a university hospital in Rio de Janeiro during the first year of the COVID-19 pandemic in Brazil. Methods: This was a cross-sectional study that used retrospective data on children (0-9 years old) and adolescents (10-18 years old) with pulmonary (PTB), extrapulmonary (EPTB), and combined tuberculosis (PTB + EPTB) followed up at the outpatient clinic from January 2019 to March 2021. Categorical data were analyzed by descriptive statistics and expressed as frequency and proportions. Categorical variables were compared using the Chi-square test, and numerical variables using Student's T-test. Results: A total of 51 cases were included, 63% (32/51) of which comprised patients in the year of the pandemic (group A), while 37% (19/51) were patients attended in previous years (group B). In group A, 19% (6/32) of the patients presented PTB, 59% (16/32) had EPTB, and 31% (10/32) had PTB+EPTB. In group B, 42% (8/19) of the patients presented PTB, 42% (8/19) had EPTB, and 16% (3/19) had PTB+EPTB. Conclusion: Our study revealed more tuberculosis cases in the first year of the pandemic than in the same period of the previous year, with greater variation of sites affected by the disease, including rarer and more severe forms.

Keywords: pandemic, children, adolescents, tuberculosis, coronavirus.

Objective: To correlate tomographic findings with pulmonary function findings, as well as to compare chest X-ray findings with high-resolution computed tomography (HRCT) findings, in patients with silicosis. Methods: A cross-sectional study was conducted in 44 non-smoking patients without a history of tuberculosis. Chest X-ray findings were classified according to the International Labour Organization recommendations. Using a semiquantitative system, the following HRCT findings were measured: the full extent of pulmonary involvement; parenchymal opacities; and emphysema. Spirometry and forced oscillation were performed. Pulmonary volumes were evaluated using the helium dilution method, and diffusing capacity of the lung for carbon monoxide was assessed. Results: Of the 44 patients studied, 41 were male. The mean age was 48.4 years. There were 4 patients who were classified as category 0 based on X-ray findings and as category 1 based on HRCT findings. Using HRCT scans, we identified progressive massive fibrosis in 33 patients, compared with only 23 patients when X-rays were used. Opacity score was found to correlate most closely with airflow, DLCO and compliance. Emphysema score correlated inversely with volume, DLCO and airflow. In this sample of patients presenting a predominance of large opacities (75% of the individuals), the deterioration of pulmonary function was associated with the extent of structural changes. Conclusions: In the early detection of silicosis and the identification of progressive massive fibrosis, HRCT scans are superior to X-rays.

Keywords: Silicosis; Occupational diseases; Tomography, x-ray computed; Respiratory function tests.

Objective: To compare gastric lavage (GL) performed in inpatients with GL performed in outpatients in terms of its accuracy in diagnosing pulmonary tuberculosis (TB) in children. Methods: A prospective study was carried out in the state of Espírito Santo, Brazil, from 1999 to 2003. A total of 230 children suspected of having TB (103 inpatients and 127 outpatients) were selected to undergo GL. Those thus diagnosed with TB (n = 53) were divided into two groups: inpatient GL (n = 30) and outpatient GL (n = 23). All 53 children were monitored for 6 months in order to evaluate the accuracy of the diagnosis. Accuracy was determined based on any change in diagnosis, cure rate, and the percentage of positive cultures in the two groups studied. Results: The cure rate was 100% in both groups, and there was no change in diagnosis in the 53 children studied. No significant difference was found between the two groups studied in terms of detection of Mycobacterium tuberculosis (RR = 1.47; 95% CI: 0.95-2.27; p = 0.095), although the outpatient group presented a greater rate of positive cultures. Conclusions: Our results show that the accuracy of GL performed in an inpatient setting is similar to that of GL performed in an outpatient setting. This indicates that hospitalization is required only in more severe cases in which GL cannot be performed as an outpatient procedure.

Keywords: Gastric lavage; Tuberculosis; Diagnosis.

Abstract Objective: To compare four laboratory methods in the diagnosis of pulmonary tuberculosis. Methods: Respiratory secretion specimens were collected from 160 patients suspected of having pulmonary tuberculosis. Direct testing for Mycobacterium tuberculosis was carried out using Ziehl-Neelsen staining, auramine staining, culture on Löwenstein-Jensen (LJ) medium and polymerase chain reaction (PCR). The strains isolated were identified by means of a radiometric method using p-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) and classical methods. The sensitivity of the methods was compared to the gold standard for the diagnosis of pulmonary tuberculosis, based on clinical, radiological and microbiological criteria. Results: Of the 160 patients, 142 were diagnosed with pulmonary tuberculosis according to the gold standard. The sensitivity of Ziehl-Neelsen staining, auramine staining, culture on LJ medium and PCR was 54.2%, 58.4%, 67.6% and 77.5%, respectively, when compared with the diagnostic criterion adopted. All four methods presented 100% specificity. In the identification of mycobacteria, there was high (96.8%) concordance between PCR and the radiometric method using NAP. The sensitivity of PCR was 50.8% in samples with negative sputum smear microscopy results and 98.8% in those with positive results. The sensitivity of PCR was lower in specimens with negative results in sputum smear microscopy and culture than in those with positive results (25.6% and 99.0%, respectively). Conclusions: We found PCR to be a promising method for the diagnosis of pulmonary tuberculosis, even in paucibacillary specimens. Simultaneous identification and faster results are additional advantages of this method.

Keywords: Tuberculosis, pulmonary/diagnosis; Culture media; Polymerase chain reaction; Sputum/microbiology.

Objective: To compare the frequency of unfavorable outcome (death or default and treatment failure) between tuberculosis (TB)/HIV co-infected patients treated for TB after laboratory confirmation of the diagnosis and TB/HIV co-infected patients who were so treated without diagnostic confirmation. Methods: A retrospective cohort of TB/HIV co-infected patients who started TB treatment between July of 2002 and June of 2004 at an HIV/AIDS referral center in Recife, Brazil. The main exposure variable, laboratory confirmation of TB, was adjusted for three different sets of variables: sociodemographic variables; HIV/AIDS-related variables; and TB-related variables. In order to evaluate the statistical significance of the results, we calculated odds ratios, with 95% confidence intervals, and p values (from chi-square tests and likelihood ratio tests). Results: A total of 262 patients were studied. No association was found between laboratory confirmation of the diagnosis of TB at treatment outset and unfavorable outcome, even after adjustment for confounders. In the final multiple logistic regression model, the following variables remained: the presence of other opportunistic diseases; CD4 lymphocyte count below 50 cells/mm3; viral load between 10,000 and 100,000 copies/mL; dyspnea; the disseminated form of TB; and change in the TB treatment regimen due to adverse reactions or intolerance. Conclusions: Our results suggest that TB treatment in TB/HIV co-infected patients without etiologic confirmation of TB, at the discretion of experienced physicians in referral centers, did not increase the risk of unfavorable outcomes. In addition, it allowed the identification of groups that should be closely monitored due to a greater risk of unfavorable outcomes.

Keywords: Tuberculosis; Diagnosis; Therapeutics; Treatment outcome; HIV infections.

Objective: To investigate the characteristics of and risk factors for mortality among non-HIV-infected immunocompromised patients with an in-hospital diagnosis of tuberculosis. Methods: This was a two-year, retrospective cohort study of patients with an in-hospital diagnosis of tuberculosis. The predictive factors for mortality were evaluated. Results: During the study period, 337 hospitalized patients were diagnosed with tuberculosis, and 61 of those patients presented with immunosuppression that was unrelated to HIV infection. Extrapulmonary tuberculosis was found in 47.5% of cases. In the latter group, the in-hospital mortality rate was 21.3%, and the mortality rate after discharge was 18.8%. One-year survival was significantly higher among the immunocompetent patients than among the HIV patients (p = 0.008) and the non-HIV-infected immunocompromised patients (p = 0.015), although there was no such difference between the two latter groups (p = 0.848). Among the non-HIV-infected immunocompromised patients, the only factor statistically associated with mortality was the need for mechanical ventilation. Among the patients over 60 years of age, fibrosis/atelectasis on chest X-rays and dyspnea were more common, whereas fever and consolidations were less common. Fever was also less common among the patients with neoplasms. The time from admission to the initiation of treatment was significant longer in patients over 60 years of age, as well as in those with diabetes and those with end-stage renal disease. Weight loss was least common in patients with diabetes and in those using corticosteroids. Conclusions: The lower prevalence of classic symptoms, the occurrence of extrapulmonary tuberculosis, the delayed initiation of treatment, and the high mortality rate reflect the diagnostic and therapeutic challenges of tuberculosis in non-HIV-infected immunocompromised patients.

Keywords: Hospitalization; Immunosuppression; Risk factors; Tuberculosis/mortality; Immunocompromised host.

Background: In Brazil, tuberculosis is the major cause of pleural effusion. In more than 50% of cases, treatment has been initiated prior to confirmation of the diagnosis. Our objective was to identify factors that can contribute to the diagnosis. Method: We studied 215 consecutive patients with pleural effusion: 104 from tuberculosis (TB) and 111 from other causes (41 were from malignancies, 29 involved transudation, 28 were parapneumonic and 13 were from other etiologies). Clinical, radiological and laboratorial variables were evaluated for differences between the two groups, individually or in combination. Results: Male gender and PPD > 10 mm were significantly more frequent in the tuberculosis group. Radiological features were similar in both groups. Among the continuous variables, adenosine deaminase (ADA), percentile of cells, protein and age performed better as isolated diagnostic criteria. Between the group with tuberculosis and that with pleural effusion from other causes, no significant differences were found in Lactate dehydrogenase, total leukocytes or duration of disease. The correlation of ADA with any other welldeveloped continuous variable showed an LR+ > 10 and an LR- < 0.1, which effectively confirmed or ruled out a diagnosis of tuberculous pleural effusion. Conclusions: In patients with ADA levels > 39 at 95% sensitivity, the specificity can be improved to more than 90% if we consider non purulent effusion or effusion with a predominance of lymphocytes (> 50%).

Keywords: Tuberculosis, pleural/diagnosis. Adenosine deaminase/diagnosis use. Sensitivity and specificity.

Objective: To evaluate the accuracy of bacteriological methods and of polymerase chain reaction (with primers specific for IS6110 of the Mycobacterium tuberculosis complex) in testing sputum samples from indigenous (Amerindian) and non-indigenous patients. Methods: A total of 214 sputum samples (154 from indigenous patients and 60 from non-indigenous patients) were analyzed in order to determine the accuracy of smear microscopy (direct and concentrated versions) for acid-fast bacilli, culture, and polymerase chain reaction. Results: Both microscopy methods presented low sensitivity in comparison with culture and polymerase chain reaction. Specificity ranged from 91% to 100%, the concentrated acid-fast smear technique being the least specific. Nontuberculous mycobacteria were isolated three times more frequently in samples from indigenous patients than in those from non-indigenous patients. False-positive and false-negative polymerase chain reaction results were more common in the indigenous population. Conclusion: Positivity and isolation of nontuberculous mycobacteria in the acid-fast smear in conjunction with polymerase chain reaction positivity raise the following hypotheses: nontuberculous mycobacteria species with DNA regions homologous to, or even still possessing, the M. tuberculosis IS6110 exist in the Amazon; colonization of the oropharynx or of a tuberculous lesion accelerates the growth of the nontuberculous mycobacteria present in the sputum samples, making it impossible to isolate M. tuberculosis; A history of tuberculosis results in positivity for M. tuberculosis DNA. The absence of bacteriological positivity in the presence of polymerase chain reaction positivity raises questions regarding the inherent technical characteristics of the bacteriological methods or regarding patient history of tuberculosis.

Keywords: Tuberculosis, pulmonary/diagnosis; Mycobacterium tuberculosis, Polymerase chain reaction/methods; Indians, south american

Objective: To evaluate the quality of diagnosis and the epidemiological profile of patients with pleural tuberculosis in the state of Roraima, Brazil, in order to provide technical support for the development and implementation of public policies to combat the disease. Methods: This was a cross-sectional study designed to determine the prevalence of pleural forms of tuberculosis in Roraima between 2005 and 2013 and to evaluate the diagnostic criteria used, as well as their determinants. This study was based on secondary data from the Brazilian Case Registry Database, including all reported cases of pleural tuberculosis in the state during the study period. Diagnoses based on bacteriological or histopathological confirmation were defined as high-quality diagnoses. Results: Among the 1,395 cases of tuberculosis reported during the study period, 116 (8.3%) were cases of pleural tuberculosis, accounting for 38.9% of all cases of extrapulmonary tuberculosis in the sample. The incidence rate of pleural tuberculosis did not follow the downward trend observed for the pulmonary form of the disease during the same period. The prevalence of cases with a high-quality diagnosis was 28.5% (95% CI: 20.4-37.6%). In a univariate analysis, none of the demographic or clinical characteristics collected from the database were found to have a significant impact on the outcome (as explanatory variables). Conclusions: The quality of the diagnoses in our study sample was considered unsatisfactory. Limited access to specific diagnostic methods might have contributed to these results.

Keywords: Tuberculosis/diagnosis; Tuberculosis/epidemiology; Tuberculosis, pleural.

Objective: To evaluate tuberculosis diagnosis with the use of the lateral flow urine lipoarabinomannan assay (LF-LAM) in addition to the Xpert® MTB/RIF Ultra assay on sputum in HIV-positive inpatients and outpatients. Methods: This was a prospective cross-sectional study including HIV-positive patients = 18 years of age with an indication for LF-LAM in accordance with Brazilian National Ministry of Health criteria. Results: A total of 140 patients were included in the study. LF-LAM was positive in 23 (16.4%). An additional 12 (8.6%) were diagnosed with the aid of LF-LAM, this increase in tuberculosis detection being statistically significant. LF-LAM-positive patients were younger and had lower CD4 counts in comparison with LF-LAM-negative patients. Smoking was more common among LF-LAM-negative patients than among LF-LAM-positive patients. Conclusions: The use of LF-LAM significantly increases the detection of tuberculosis in HIV-positive patients, mostly in those who are hospitalized. These findings highlight the utility of LF-LAM, especially in regions with high tuberculosis and HIV infection incidence.

Keywords: Tuberculosis; Mycobacterium tuberculosis; HIV infections; Diagnosis.

Objective: Silicosis is a pneumoconiosis characterized by fibrosis of the lung parenchyma caused by inhalation of silica particles. Genetic factors might play a role in the severity silicosis. We sought to evaluate the influence of polymorphisms in the ACE, FAS, FASLG, NOS2, IL1RN, FAM13A, TGFB1, and TNF genes on the severity of silicosis. Methods: Nine polymorphisms were genotyped by PCR in a sample of 143 patients with silicosis in the state of Rio de Janeiro, Brazil. Results: Fifty-seven patients (40%) were classified as having simple silicosis and 86 (60%) were classified as having complicated silicosis. The TT genotype of rs1800469 in the TGFB1 gene showed a protective effect for complicated silicosis (OR = 0.35; 95% CI, 0.14-0.92; p = 0.028) when compared with the other two genotypes (CC+CT). The polymorphic T allele of rs763110 in the FASLG gene (OR = 0.56; 95% CI, 0.31-0.99; p = 0.047), as well as a dominant model for the T allele (TT+CT: OR = 0.37; 95% CI, 0.15-0.96; p = 0.037), also showed a protective effect. When patients with simple silicosis despite having been exposed to silica for a longer time (> 44,229 hours) were compared with patients with complicated silicosis despite having been exposed to silica for a shorter time, the T allele of rs763110 in the FASLG gene (OR = 0.20; 95% CI, 0.08-0.48; p < 0.0001), as well as dominant and recessive models (OR = 0.06; 95% CI, 0.00-0.49; p = 0.01 and OR = 0.22; 95% CI, 0.06-0.77; p = 0.014, respectively), showed a protective effect against the severity of silicosis. Conclusions: It appears that rs1800469 polymorphisms in the TGFB1 gene and rs763110 polymorphisms in the FASLG gene are involved in the severity of silicosis. Given the lack of studies relating genetic polymorphisms to the severity of silicosis, these results should be replicated in other populations.

Keywords: Silicosis; Polymorphism, genetic; Genetic association studies; Cytokines.

Objective: To determine the clinical and epidemiological profile of patients who are candidates for TNF-α inhibitor use and are classified as having latent tuberculosis (LTB), as well as to evaluate the outcomes of prophylactic treatment with isoniazid. Methods: A prospective descriptive analysis followed by an analytical, observational, cross-sectional study of the outcomes of prophylactic treatment in a group of 45 candidates for TNF-α inhibitor use. We evaluated the patients through anamnesis, clinical examination, chest X-ray, and tuberculin skin test (TST) using the Mantoux method. Results: The mean age was 45 years, and 56.0% of the patients were female. Chronic rheumatic diseases, chronic dermatological diseases, and Crohn's disease were present in 46.7%, 40.0%, and 13.3% of the patients, respectively. The mean TST induration was 14.6 mm (range: 5-30 mm). The majority (n = 30) of the 45 patients (66.7%) had an induration > 10 mm. In the 16 patients with BCG vaccination scars, the mean induration was 15.7 mm, and 14 of those patients had an induration > 10 mm. Chest X-ray results were considered normal, with minimal alterations, in 64.4% and 35.6% of the patients, respectively. The treatment with isoniazid was abandoned by 1 patient (2.2%) and completed by 41 (91.2%), whereas it was interrupted because of drug-induced hepatitis in 2 (4.4%), and 1 patient (2.2%) was transferred to another hospital. Of those who completed the treatment, 5 experienced mild side effects. Conclusions: Determining the profile of candidates for TNF-α inhibitor use is important for the management of LTB treatment and for the establishment of clinical protocols for the use and monitoring of the use of these medications.

Keywords: Tuberculosis; Latent tuberculosis; Tuberculin test; Isoniazid; Tumor necrosis factor-alpha.

Introduction: Bronchoscopy is useful in the diagnosis of tuberculosis suspects with a "negative" sputum smear. The objectives of this study were: to assess yield of bronchoalveolar lavage (BAL) and of transbronchial biopsy (TBB) both in HIV-positive patients (group 1) and immunocompetent individuals (group 2), based on simple and most available laboratory techniques in clinical practice. Patients and methods: The authors performed 319 bronchoscopies in 302 patients. BAL and TBB were sequentially performed in the same lung in all cases. Tuberculosis was diagnosed based on the results of acid-fast stains (AFS) from the lavage (ZN), culture for mycobacteria (LJ), and histological examination of biopsies (HE and ZN). Results: Tuberculosis was the final diagnosis in 28 exams of group 1 (n = 214) and in 35 of group 2 (n = 105). There were abnormal endoscopic findings respectively in 3 and 10 patients. In group 1, AFS were positive in 7 cases, culture of BAL in 14, and TBB in 19. In group 2, AFS were positive in 13 cases, culture in 17, and biopsies in 31. TBB results compared to BAL were in concordance for group 1 (p = 0.823) and different for group 2 (p = 0.022). Immediate results (AFS and TBB) compared to later positive results of culture were similar for group 1 (p = 0.066) but not for group 2 (p = 0.001). There were eight episodes of pneumothorax (2.5%) and one death (0.36%). Conclusions: Both BAL and TBB should be performed whenever possible, aiming towards a higher yield of bronchoscopy in the diagnosis of tuberculosis. Both methods complement each other in immunocompetent patients, whereas TBB establishes a faster diagnosis for HIV-infected patients if associated to AFS.

Keywords: Bronchoscopy/methods. Smear-negative tuberculosis/diagnosis. Opportunistic infections related to AIDS/diagnosis.