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 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 compare clinical, radiological, and laboratory characteristics of individuals with pulmonary tuberculosis co-infected or not with HIV. Methods: A cross-sectional study, in which signs and symptoms were assessed by anamnesis and physical examination in patients hospitalized with pulmonary tuberculosis. The results of sputum smear microscopy and culture for Mycobacterium tuberculosis, as well as hemoglobin levels and CD4+ T-cell counts, were obtained from medical records, and chest X-ray reports were consulted. Results: We included 50 pulmonary tuberculosis patients, who were divided into two groups (HIV-positive and HIV-negative; n = 25 per group). The mean age of the participants was 38.4 ± 10.5 years; 46 (92%) were males; and 27 (54%) were White. Expectoration was presented by 21 (84%) and 13 (52%) of the patients in the HIV-negative and HIV-positive groups, respectively (p = 0.016). Radiological findings of cavitation were present in 10 (43%) and 2 (10%) of the patients in the HIV-negative and HIV-positive groups, respectively (p = 0.016), whereas an interstitial pattern was observed in 18 (78%) and 8 (40%), respectively (p = 0.012). The mean hemoglobin level was 11.1 ± 2.9 g/dL and 9.3 ± 2.2 g/dL in the HIV-negative and HIV-positive groups, respectively (p = 0.015). Conclusions: In our sample of tuberculosis patients, expectoration was less prevalent, hemoglobin levels were lower, and cavitation was less common, as was an interstitial pattern, among those co-infected with HIV than among those without HIV co-infection.

Keywords: HIV; Tuberculosis; Acquired immunodeficiency syndrome.

Objective: To describe the differences in the clinical and radiological presentation of tuberculosis in the presence or absence of HIV infection. Methods: A sample of 231 consecutive adults with active pulmonary tuberculosis admitted to a tuberculosis hospital were studied, assessing HIV infection, AIDS, and associated factors, as well as re-evaluating chest X-rays. Results: There were 113 HIV-positive patients (49%) Comparing the 113 HIV-positive patients (49%) to the 118 HIV-negative patients (51%), the former presented a higher frequency of atypical pulmonary tuberculosis (pulmonary lesions accompanied by intrathoracic lymph node enlargement), hematogenous tuberculosis, and pulmonary tuberculosis accompanied by superficial lymph node enlargement, as well as presenting less pulmonary cavitation. The same was found when HIV-positive patients with AIDS were compared to those without AIDS. There were no differences between the HIV-positive patients without AIDS and the HIV-negative patients. Median CD4 counts were lower in HIV-positive patients with intrathoracic lymph node enlargement and pulmonary lesions than in the HIV-positive patients with pulmonary lesions only (47 vs. 266 cells/mm3; p < 0.0001), in HIV-positive patients with AIDS than in those without AIDS (136 vs. 398 cells/mm3; p < 0.0001) and in patients with atypical pulmonary tuberculosis than in those with other forms of tuberculosis (31 vs. 258 cells/mm3; p < 0.01). Conclusion: Atypical forms and disseminated disease predominate among patients with advanced immunosuppression. In regions where TB prevalence is high, the presence of atypical pulmonary tuberculosis or pulmonary tuberculosis accompanied by superficial lymph node enlargement should be considered an AIDS-defining condition.

Keywords: Tuberculosis, pulmonary; HIV infections; Radiography, thoracic.

Objective: To investigate the diagnostic accuracy of a chest X-ray (CXR) score and of clinical and laboratory data in predicting the clinical course of patients with SARS coronavirus 2 (SARS-CoV-2) infection. Methods: This is a pilot multicenter retrospective study including patients with SARS-CoV-2 infection admitted to the ERs in three hospitals in Italy between February and March of 2020. Two radiologists independently evaluated the baseline CXR of the patients using a semi-quantitative score to determine the severity of lung involvement: a score of 0 represented no lung involvement, whereas scores of 1 to 4 represented the first (less severe) to the fourth (more severe) quartiles regarding the severity of lung involvement. Relevant clinical and laboratory data were collected. The outcome of patients was defined as severe if noninvasive ventilation (NIV) or intubation was necessary, or if the patient died. Results: Our sample comprised 140 patients. Most of the patients were symptomatic (132/138; 95.7%), and 133/140 patients (95.0%) presented with opacities on CXR at admission. Of the 140 patients, 7 (5.0%) showed no lung involvement, whereas 58 (41.4%), 31 (22.1%), 26 (18.6%), and 18 (12.9%), respectively, scored 1, 2, 3, and 4. In our sample, 66 patients underwent NIV or intubation, 37 of whom scored 1 or 2 on baseline CXR, and 28 patients died. Conclusions: The severity score based on CXR seems to be able to predict the clinical progression in cases that scored 0, 3, or 4. However, the score alone cannot predict the clinical progression in patients with mild-to-moderate parenchymal involvement (scores 1 and 2).

Keywords: Coronavirus infections; Radiography, thoracic; Pneumonia; Respiratory insufficiency; Severe acute respiratory syndrome.

Objective: To predict COVID-19 in hospitalized patients with SARS in a city in southern Brazil by using machine learning algorithms. Methods: The study sample consisted of patients = 18 years of age admitted to the emergency department with SARS and hospitalized in the Hospital Escola - Universidade Federal de Pelotas between March and December of 2020. Epidemiological, clinical, and laboratory data were processed by machine learning algorithms in order to identify patterns. Mean AUC values were calculated for each combination of model and oversampling/undersampling techniques during cross-validation. Results: Of a total of 100 hospitalized patients with SARS, 78 had information for RT-PCR testing for SARS-CoV-2 infection and were therefore included in the analysis. Most (58%) of the patients were female, and the mean age was 61.4 ± 15.8 years. Regarding the machine learning models, the random forest model had a slightly higher median performance when compared with the other models tested and was therefore adopted. The most important features to diagnose COVID-19 were leukocyte count, PaCO2, troponin levels, duration of symptoms in days, platelet count, multimorbidity, presence of band forms, urea levels, age, and D-dimer levels, with an AUC of 87%. Conclusions: Artificial intelligence techniques represent an efficient strategy to identify patients with high clinical suspicion, particularly in situations in which health care systems face intense strain, such as in the COVID-19 pandemic.

Keywords: COVID-19/diagnosis; Artificial intelligence; Machine learning.

Objective: To evaluate the radiological presentation of patients with pulmonary tuberculosis diagnosed in the emergency department and to investigate its association with the time to diagnosis. Methods: This was a prospective observational study involving patients diagnosed with pulmonary tuberculosis in the emergency department of a tertiary university hospital in southern Brazil. Chest X-rays taken on admission were evaluated by a radiologist. The various patterns of radiological findings and locations of the lesions were described. The main study outcome was the total time elapsed between the initial radiological examination and the diagnosis of tuberculosis. Results: A total of 78 patients were included in the study. The median time from chest X-ray to diagnosis was 2 days, early and delayed diagnosis being defined as a time to diagnosis < 2 days and ≥ 2 days, respectively. Sputum smear positivity was associated with early diagnosis (p = 0.005), and positive culture was associated with delayed diagnosis (p = 0.005). Early diagnosis was associated with the presence of sputum (p = 0.03), weight loss (p = 0.047), cavitation (p = 0.001), and consolidation (p = 0.003). Pulmonary cavitation was found to be an independent predictor of early diagnosis (OR = 3.50; p = 0.028). Conclusions: There is a need for tuberculosis-specific protocols in emergency departments, not only to avoid delays in diagnosis and treatment but also to modify the transmission dynamics of the disease.

Keywords: Tuberculosis/diagnosis; Emergency medical services; Radiography, thoracic.

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: 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 evaluate the frequency of asthma-COPD overlap (ACO) in patients with COPD and to compare, from a clinical, laboratory, and functional point of view, patients with and without ACO, according to different diagnostic criteria. Methods: The participants underwent evaluation by a pulmonologist, together with spirometry and blood tests. All of the patients were instructed to record their PEF twice a day. The diagnosis of ACO was based on the Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (PLATINO, Latin American Project for the Investigation of Obstructive Lung Disease) criteria, the American Thoracic Society (ATS) Roundtable criteria, and the Spanish criteria. We investigated patient histories of exacerbations and hospitalizations, after which we applied the COPD Assessment Test and the modified Medical Research Council scale, to classify risk and symptoms in accordance with the GOLD criteria. Results: Of the 51 COPD patients, 14 (27.5%), 8 (12.2%), and 18 (40.0) were diagnosed with ACO on the basis of the PLATINO, ATS Roundtable, and Spanish criteria, respectively. The values for pre-bronchodilator FVC, post-bronchodilator FVC, and pre-bronchodilator FEV1 were significantly lower among the patients with ACO than among those with COPD only (1.9 ± 0.4 L vs. 2.4 ± 0.7 L, 2.1 ± 0.5 L vs. 2.5 ± 0.8 L, and 1.0 ± 0.3 L vs. 1.3 ± 0.5 L, respectively). When the Spanish criteria were applied, IgE levels were significantly higher among the patients with ACO than among those with COPD only (363.7 ± 525.9 kU/L vs. 58.2 ± 81.6 kU/L). A history of asthma was more common among the patients with ACO (p < 0.001 for all criteria). Conclusions: In our sample, patients with ACO were more likely to report previous episodes of asthma and had worse lung function than did those with COPD only. The ATS Roundtable criteria appear to be the most judicious, although concordance was greatest between the PLATINO and the Spanish criteria.

Keywords: Asthma/diagnosis; Pulmonary disease, chronic obstructive/diagnosis; Asthma-chronic obstructive pulmonary disease overlap syndrome/diagnosis.

Objective: To evaluate the accuracy of determining the adenosine deaminase (ADA) level, the 2'-deoxyadenosine/ADA ratio, and the LDH/ADA ratio in pleural fluid for the diagnosis of pleural tuberculosis (PT) in children and adolescents. Methods: This was a retrospective cross-sectional study conducted at a tertiary hospital in a high-tuberculosis-incidence area, between 2001 and 2018. All patients with ADA in pleural fluid and a confirmed diagnosis of PT (cPT) or parapneumonic effusion (PPE) were included. Results: The cPT and PPE groups comprised 25 and 68 individuals, respectively. At a cutoff of 40 U/L, ADA measurement showed the following: sensitivity, 88%; specificity, 31%; positive predictive value (PPV), 32%; negative predictive value (NPV), 88%; and overall accuracy, 46%. The best cutoffs were an ADA level of 125 U/L, a 2'-deoxyadenosine/ADA ratio of 0.5, and an LDH/ADA ratio of 8.3, with AUC of 0.67, 0.75, and 0.82, respectively. The sensitivity, specificity, PPV, NPV, and overall accuracy of the 125 U/L ADA cutoff were 84%, 65%, 47%, 92%, and 70%, respectively, compared with 79%, 79%, 59%, 91%, and 79%, respectively, for the 8.3 LDH/ADA ratio cutoff. Changing the LDH/ADA ratio cutoff to 3.0 increased the specificity to 98%. Conclusions: The ADA level and the 2'-deoxyadenosine/ADA ratio are not good biomarkers for the diagnosis of PT in pediatric patients. Determination of the LDH/ADA ratio provides the best overall accuracy for the diagnosis of PT in such patients.

Keywords: Adenosine deaminase; Pleural effusion; Tuberculosis, pleural/diagnosis; Child; Adolescent.

Background: Synergism between tuberculosis and HIV is responsible for the increased morbidity-mortality rate in AIDS patients. Objective: To delineate the profile of patients with tuberculosis and AIDS in the city of Rio Grande by relating demographic, clinical and laboratory data. Method: The sample comprised all cases of tuberculosis defined by identification of Mycobacterium tuberculosis that occurred in the AIDS Service of the University Hospital/FURG between September, 1997 and December, 2000, which added to a total of 31 patients confirmed as definite cases of AIDS. Using the Ogawa-Kudoh culture method and the Kinyoun bacilloscopy, 33 clinical pulmonary and extrapulmonary specimens were analyzed. Identification of M. tuberculosis was made by the usual phenotype methods. The method of proportions was chosen to establish resistance of isolated strains. Results: The mean age was of 33.8±9.9 years, with a man/woman ratio of 2.87:1 and 80.7% of Caucasians. All patients (n=31) exhibited overall or specific clinical manifestations of turberculosis at the time of suspicion diagnosis. In 20 of the cases risk factors were observed: use of injected drugs, alcoholism, malnutrition, imprisonment. Pulmonary disease occurred in 19 cases, extrapulmonary in 10 and the association of both in two. Lymph node commitment was more frequent among those with extrapulmonary disease. The isolated strains (33) were identified as M. tuberculosis and 28 were tested and showed sensibility to Isoniazid and Rifampin. Conclusion: In AIDS patients, tuberculosis appeared with various clinical manifestations, jeopardizing both men and women of less favored social conditions while at a fully productive stage of their lives.

Keywords: Tuberculosis/epidemiology. Tuberculosis/complications. Acquired immunodeficiency syndorme/tuberculosis. Mycobacterium tuberculosis/indicators of morbidity and mortality.

Objective: To evaluate Brazilian studies by summarizing the accuracy of adenosine deaminase in the diagnosis of the pleural tuberculosis, with the objective of lending support to the movement to make the test part of the routine in the investigation of pleural effusions. Methods: A search for Brazilian studies related to the determination of adenosine deaminase levels in the pleural liquid was carried out. These studies were evaluated and included in this study. The data were analyzed using summary receiver operating characteristic (SROC) curves, which enabled the studies to be collected and evaluated regarding the accuracy of the diagnosis. As for the global values of sensitivity and specificity, the Bayes' theorem was applied to calculate the post-test probabilities in different prevalences of the disease. Results: Twenty-five studies dating from 1987 to 2005 and including enough information to be used in the meta-analysis were identified. After evaluation, nine studies were included, totaling 1674 patients. According to the SROC curve, a sensitivity of 91.8% (95% CI: 89.8‑93.6%) and a specificity of 88.4% (95% CI: 86.0-90.5%) were found, with an area of 0.969 below the curve. The overall odds ratio was 112.0 (95% CI: 51.6-243.2). Considering a prevalence of tuberculosis of 50% (considered neutral), the post-test probability was 88.7% for a positive test and 91.5% for a negative test. Conclusion: Despite the differences found among studies, it is possible to conclude that the determination of adenosine deaminase levels has high accuracy in the diagnosis of the pleural tuberculosis and should be used as a routine test in its investigation.

Keywords: Pleural effusion; Tuberculosis; Diagnosis; Adenosine deaminase; Meta-analysis.

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 present aspects of the evolution of lipoid pneumonia in children, based on clinical, radiological and bronchoalveolar lavage fluid findings, emphasizing the importance of bronchoalveolar lavage for the diagnosis and treatment. Methods: We included 28 children, with a mean age of 20 months (range, 1-108 months), diagnosed with chronic pneumonia refractory to antimicrobial therapy, with TB or with a combination of the two. Most of the children had at least one risk factor for aspiration, and all of them had a history of mineral oil ingestion for intestinal constipation (23/28) or complicated ascaridiasis (5/28). Clinical evaluations, tomographic evaluations and analyses of bronchoalveolar lavage fluid were carried out at the beginning of treatment and throughout a follow-up period of 24 months. Results: Tachypnea and cough were the most common symptoms. The most common radiological alterations were areas of consolidation (23/28), perihilar infiltrates (13/28) and hyperinflation (11/28). Chest CT scans showed areas of consolidation with air bronchogram (24/28), decreased attenuation in the areas of consolidation (16/28), ground-glass opacities (3/28) and crazy-paving pattern (1/28). In the analysis of the bronchoalveolar lavage fluid, Sudan staining revealed foamy macrophages, confirming the diagnosis of lipoid pneumonia. After treatment with multiple bronchoalveolar lavages (mean = 9.6), 20 children became asymptomatic, 18 of those presenting normal tomographic images. Conclusions: A diagnosis of lipoid pneumonia should be considered in patients with chronic refractory pneumonia or TB, especially if there is a history of mineral oil ingestion. Bronchoscopy with multiple bronchoalveolar lavages was an efficient treatment for the clearance of mineral oil from the lung parenchyma and the prevention of fibrosis. This strategy contributed to reducing the morbidity of lipoid pneumonia, which remains a rare diagnosis.

Keywords: Pneumonia, lipid; Bronchoalveolar lavage; Treatment outcome.

The World Health Organization (WHO) has recently recommended new technologies for the diagnosis of tuberculosis. The WHO recommendations include the development of a strategic plan for bringing the network up to grade; investment in supervision and quality control; and implementation of a system of laboratory environmental management. Without those measures having been taken, no new technology can be effectively incorporated. We surveyed the tuberculosis laboratory network in Brazil in order to identify possible bottlenecks for the incorporation of new technologies. We identified a lack of resources allocated to supervision and quality control; a low number of requests for cultures; a lack of effective laboratory information systems; and a lack of awareness regarding the future infrastructure needs of the laboratory network at the municipal level.

Keywords: Quality control; Tuberculosis; Laboratories; Clinical laboratory information systems; Technology

For diagnostic purposes of pleural tuberculosis, three pleural fragments are routinely obtained from a single site by needle biopsy. The objective of this study is to compare the diagnostic yield of the routine procedure with two different approaches: harvesting five fragments on a single site (A), and collection of fragments at an additional site (B); from the same cutaneous orifice, the needle was partially removed up to the subcutaneous tissue and redirected at a 45o angle. The authors performed a prospective study in 115 patients submitted to pleural biopsy. The first three pleural fragments were placed in a vial (VA1-3), the 5 subsequent fragments obtained at the same site were placed in a second vial (VA4-8), and the five fragments from the second site were placed in a third vial (VB1-5). Analysis of fragments from VA1-3 revealed granuloma in 72/92 tuberculosis cases (78.3%), whereas in fragments VA5-8 and VB1-5, granuloma was observed in 74/92 cases (80.5%). In 6/92 patients the diagnosis at VA1-3 was non-specific pleuritis, but granuloma was found in VA4-8, resulting in a diagnosis increment of 8.3% (adding six to the 72 patients). In 7/92 patients (7.6%) the histopathological examination at site A led to a non-specific result but granuloma was found at site B, leading to a diagnostic increment of 9.0% (7 to 78 patients). Histological concordance of two examinations by the same pathologist had a kappa index of 0.62 (0.54 to 0.7) whereas concordance between two different pathologists had a kappa index of 0.64 (0.56 to 0.72). The performance of multiple biopsies at two different sites at the pleural surface led to an additional diagnosis of 13 patients, i.e., an increase of 18% (13 to 72) relative to the routine procedure. Considering the low cost increase of obtaining the fragments, adoption of this method is recommended in routine pleural tuberculosis diagnosis.

Keywords: Tuberculosis, pleural tuberculosis, biopsy, diagnosis.

Background: The diagnosis of pleural tuberculosis continues to be a challenge due to the low sensitivity of traditional diagnostic methods. Histopathological examination of pleural tissue is the most accurate method, with a sensitivity of up to 80%. Determination of adenosine deaminase levels is a recently introduced method, although its usefulness in the diagnosis of pleural tuberculosis in Brazil has yet to better elucidated. Objective: To verify the sensitivity and specificity of an experimental method of measuring adenosine deaminase activity in pleural fluid in a series of patients with pleural effusion patients evaluated between August 1998 and November 2002 in Rio de Janeiro (RJ). Results: Out of 137 cases, 111 pleural fluid samples were available. Of those, 83 were from pleural tuberculosis patients. Among the 67 pleural tuberculosis patients tested, 10 (14.9%) presented human immunodeficiency virus. The adenosine deaminase cutoff value of 35U/L was determined by a receiver operator characteristic curve. The sensitivity, specificity and likelihood ratios (positive and negative) were 92.8%, 93.3%, 25.8 and 13.9, respectively. Mean adenosine deaminase in the pleural tuberculosis group was 84.7 ± 43.1 U/L, versus 15.9 ± 11.1 U/L in the group with other diseases. There was no significant difference in adenosine deaminase activity between patients with and without human immunodeficiency virus co-infection. Conclusions: Adenosine deaminase measurement in pleural fluid is a sensitive and specific method for the diagnosis of pleural tuberculosis and its use can preclude the need for pleural biopsy in the initial workup of pleural effusion patients. An adenosine deaminase cutoff value of 35U/L is recommended.

Keywords: Pleural fluid. Adenosine deaminase. Diagnosis. Tuberculosis. HIV