The clinical-radiographic presentation and tuberculosis prediction in patients that have undergone dry pleural biopsy, as well as its usefulness and complications, have been evaluated in this retrospective study, conducted in the Octávio Mangabeira Hospital (Salvador, Bahia, Brazil), where 107 patients consecutively submitted to this exam have been analyzed. Altogether 108 biopsies have been performed using Cope's needle (biopsies of both hemithoraxes were performed in one patient). The following diagnoses were obtained: a) tuberculosis (n = 66); b) probable tuberculosis (n = 4); c) neoplasm (n = 2); d) parapneumonic (n = 3), and e) not determined (32). Sixty-seven (62.6%) of the patients were male, and mean age was 34.5 ± 15.4 years. Analyses carried out compare patients diagnosed with tuberculosis (whether confirmed or probable) to those with different diagnoses (miscellaneous). Tuberculosis patients were younger (p < 0.01), expectoration was less frequent (p < 0.01), previous tuberculosis was less often reported (p = 0.04) and PPD reactivity was more frequent (p < 0.01). No significant differences were found between the two groups as to the extent of pleural commitment and its variation in the period observed. Presence of acinar infiltrations in the upper lobes was correlated with tuberculosis diagnosis in the 13 patients in which this feature was observed. Pleural fragments were present in 100 out of 108 cases (92.6%) and the diagnosis was made in the first biopsy in 64 out of 108 cases (59.3%). Ten minor complications have occurred (9.3%) in the 108 biopsies: 6 bloody sputums, 3 small pneumothoraxes, and one moderate subcutaneous emphysema. The authors conclude that for the various predictive indicators of tuberculosis analyzed, except for the presence of acinar infiltrations in the upper lobes, there is broad overlap between the two groups compared, meaning that a safe clinical diagnosis cannot be provided and thus reinforcing the need of performing biopsies. Dry pleural biopsy offers a satisfactory diagnostic yield in areas with high prevalence of tuberculosis and proved safe, when performed by experienced personnel.

Keywords: Pleural tuberculosis. Pleural thickening. Pleural biopsy. Diagnosis.

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

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

Objective: Previous studies have demonstrated that closed pleural biopsy (CPB) has a sensitivity of less than 60% for diagnosing malignancy. Therefore, controversy has recently emerged regarding the value of CPB as a diagnostic test. Our objective was to assess the accuracy of CPB in diagnosing malignancy in patients with pleural effusion. Methods: This was a prospective 8-year study of individuals who underwent CPB to establish the etiology of pleural effusion. Information on each patient was obtained from anatomopathological reports and medical records. When CPB findings showed malignancy or tuberculosis, the biopsy was considered diagnostic, and that was the definitive diagnosis. In cases in which biopsy histopathological findings were nonspecific, a definitive diagnosis was established on the basis of other diagnostic procedures, such as thoracoscopy, thoracotomy, fiberoptic bronchoscopy, biochemical and cellular measurements in pleural fluid, and/or microbiological tests. The accuracy of CPB was determined with 2 × 2 contingency tables. Results: A total of 1034 biopsies from patients with pleural effusion were studied. Of those, 171 (16.54%) were excluded from the accuracy analysis either because of inadequate samples or insufficient information. The results of the accuracy analysis were as follows: sensitivity, 77%; specificity, 98%; positive predictive value, 99%; negative predictive value, 66%; positive likelihood ratio, 38.5; negative likelihood ratio, 0.23; pre-test probability, 2.13; and post-test probability, 82. Conclusions: CPB is useful in clinical practice as a diagnostic test, because there is an important change from pre-test to post-test probability.

Keywords: Biopsy; Pleural effusion, malignant/diagnosis; Pleural effusion, malignant/epidemiology.

A total of 287 bronchoscopies were performed in 267 patients infected with the human immunodeficiency virus (HIV). Bronchoalveolar lavage (BAL) and transbronchial biopsies (TBB) were sequentially performed in the same lung, in all cases. Specimens were examined after routine laboratory procedures for microbiologic and histologic analysis. Age ranged from 16 to 78 (median 37.2); 228 were men (85.4%) and 39 were women. Dyspnea was the main symptom in 198 cases (69.0%) and interstitial infiltrates (diffuse or localized) were the most common findings at chest radiographs (179 patients, 62.4%). Endoscopic view was normal in 246 patients (85.7%). Mucosal lesions suggestive of Kaposi's sarcoma (KS) were visible in 12 cases (4.2%). BAL detected 97 infectious agents, simultaneous co-infection occurred in 3 cases. TBB identified 165 pathogens (9 of them in association), anticipating a better yield than BAL in the diagnosis of P. carinii (84 versus 51, respectively) and cytomegalovirus (35 v. 0). Biopsies were unique in establishing the appropriate diagnosis of extrabronchial cancer and describing inespecific pneumonitis. Altogether, a definite diagnosis was obtained by bronchoscopic examination (including endoscopic view, BAL and TBB) in 271 of 287 cases (94.4%). Infections were caused by P. carinii in 105 patients (36.6%), Mycobacterium sp in 40 (13.9%), cytomegalovirus in 35 (12.2%), C. neoformans in 13 (4.5%) etc. Malignancies (including KS) were found in 16 patients (5.6%). More than one pathologic process was present in 28 (9.8%). Nonspecific pneumonitis was diagnosed in 56 cases (19.5%) and normal lung in 20 (7.0%). Complications related to bronchoscopy were pneumothorax (8 patients, 2.8%), haemorrhage (8), thoracic pain (2) and distal pneumonia (2). Chest tubes were required in 4 patients, including one fatal case (mortality rate of 0.3%). Combining BAL and TBB results increases the diagnostic yield of bronchoscopy in AIDS, with a low complication rate. If both techniques are performed, a higher number of infectious agents and more multiple causes of pulmonary disease may be identified.

Keywords: Bronchoscopy/methods. Acquired Immunodeficiency Syndrome/complications. Opportunistic infections related to AIDS/diagnosis.

Objective: To study the clinical, radiological, and histopathological patterns of transbronchial biopsy (TBB) used in order to confirm the diagnosis in patients with clinical suspicion of interstitial lung disease (ILD) treated at a tertiary-care university hospital. Methods: We reviewed the medical records, radiology reports, and reports of transbronchial biopsies from all patients with suspected ILD who underwent TBB between January of 1999 and December of 2006 at the Hospital das Clínicas de Botucatu, located in the city of Botucatu, Brazil. Results: The study included 56 patients. Of those, 11 (19.6%) had a definitive diagnosis of idiopathic pulmonary fibrosis (IPF), the rate of which was significantly higher in the patients in which ILD was a possible diagnosis in comparison with those in which ILD was the prime suspect (p = 0.011), demonstrating the contribution of TBB to the diagnostic confirmation of these diseases. The histopathological examination of the biopsies revealed that 27.3% of the patients with IPF showed a pattern of organizing pneumonia, which suggests greater disease severity. The most common histological pattern was the indeterminate pattern, reflecting the peripheral characteristic of IPF. However, the fibrosis pattern showed high specificity and high negative predictive value. For CT scan patterns suggestive of IPF, the ROC curve showed that the best relationship between sensitivity and specificity occurred when five radiological alterations were present. Honeycombing was found to be strongly suggestive of IPF (p = 0.01). Conclusions: For ILDs, chest CT should always be performed, and TBB should be used in specific situations, according to the suspicion and distribution of lesions.

Keywords: Lung diseases, interstitial; Diagnosis, differential; Bronchoscopy.

Objective: To investigate the clinical application of CT and CT-guided percutaneous transthoracic needle biopsy (CT-PTNB) in patients with indeterminate pulmonary nodules (IPNs). Methods: We retrospectively studied 113 patients with PNs undergoing CT and CT-PTNB. Variables such as gender, age at diagnosis, smoking status, CT findings, and CT-PTNB techniques were analyzed. Data analysis was performed with the Student's t-test for independent samples the chi-square test, and normal approximation test for comparison of two proportions. Results: Of the 113 patients studied, 68 (60.2%) were male and 78 (69%) were smokers. The diameter of malignant lesions ranged from 2.6 cm to 10.0 cm. Most of the IPNs (85%) were located in the peripheral region. The biopsied IPNs were found to be malignant in 88 patients (77.8%) and benign in 25 (22.2%). Adenocarcinoma was the most common malignant tumor, affecting older patients. The IPN diameter was significantly greater in patients with malignant PNs than in those with benign IPNs (p < 0.001). Having regular contour correlated significantly with an IPN being benign (p = 0.022), whereas spiculated IPNs and bosselated IPNs were more often malignant (in 50.7% and 28.7%, respectively). Homogeneous attenuation and necrosis were more common in patients with malignant lesions (51.9% and 26.9%, respectively) Conclusions: In our sample, CT and CT-PTNB were useful in distinguishing between malignant and benign IPNs. Advanced age and smoking were significantly associated with malignancy. Certain CT findings related to IPNs (larger diameter, spiculated borders, homogeneous attenuation, and necrosis) were associated with malignancy.

Keywords: Solitary pulmonary nodule; Tomography; Image-guided biopsy.

Objective: To evaluate the results of thoracoscopy for the treatment of pleural empyema in pediatric patients. Methods: A retrospective study of 117 patients who underwent mediastinoscopy or video-assisted thoracoscopy for pleural empyema treatment. General anesthesia and single-lumen oral intubation were used. Surgery was indicated when there was pleural effusion and no clinical and radiological response to clinical treatment (antibiotics, physiotherapy and thoracocentesis) or severe sepsis, together with loculated pleural effusion (confirmed through ultrasound or computed tomography of the chest). Results: Between February of 1983 and July of 2006, 117 thoracoscopies were performed in patients ranging in age from 5 months to 17 years (mean, 4 years). Mean time for thoracic drainage was 9 days (range, 2-33 days), and mean period of hospitalization was 16.4 days (range, 4 to 49 days). One patient (0.8%) died after surgery, and persistent fistula was observed in 33 patients (28%). In 7 cases (6%), open thoracotomy with pulmonary decortication was performed due to the disposition of the empyema. Conclusions: Management of pleural empyema in this age bracket is still controversial, and surgical indication is often delayed, particularly when there are multiple loculations or severe sepsis. Early thoracoscopy yields a better clinical outcome for pediatric patients with pleural empyema, with apparent decreased morbidity and mortality, earlier chest tube removal, earlier hospital discharge and improved response to antibiotic therapy.

Keywords: Empyema, pleural; Pediatrics/instrumentation; Thoracoscopy; Thoracic surgery, video-assisted.

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.

Objective: The aim of this study was to determine the factors associated with nocturnal, productive and dry cough among young adults in Nigeria. Methods: We evaluated 498 subjects, 20-44 years of age, in Ilorin, Nigeria, using the European Community Respiratory Health Survey (ECRHS) questionnaire, administered by trained interviewers. Results: Nocturnal cough was associated with asthma (OR = 10.87; p < 0.01), nasal allergy (OR = 6.33; p < 0.01), smoking (OR = 3.10; p < 0.01), skilled manual and non-manual work (OR = 2.86 and 2.10, respectively; p < 0.01 for both) and female gender (OR = 1.33; p = 0.17). Productive cough was associated with skilled manual and non-manual work (OR = 3.82 and 3.03, respectively; p < 0.01 for both), smoking (OR = 3.10; p < 0.01), asthma (OR = 3.27; p < 0.01) and nasal allergy (OR = 5.81; p < 0.01). Dry cough was associated with asthma (OR =5.18; p < 0.01) obesity (OR =1.88; p = 0.19), smoking (OR = 1.77; p = 1.44), nasal allergy (OR = 1.45; p = 0.26) and female gender (OR =1.36; p = 0.33). Age, gender, type of residence and obesity were not significantly associated with any type of cough (p > 0.05). Conclusions: Early prevention and treatment of conditions associated with cough, as well as the modification of social factors commonly associated with cough, are needed in order to reduce respiratory morbidity.

Keywords: Cough; Smoking; Asthma; Rhinitis; Nigeria.

Objective: To determine the levels of the tumor markers carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1) and carbohydrate antigen 15-3 (CA 15-3) in the blood and pleural fluid of patients with benign or malignant pleural effusion, evaluating the sensitivity of each marker in these fluids. Methods: We prospectively evaluated 85 patients with pleural effusion. The study of the pleural fluid observed the criteria established in the literature. Levels of the markers were determined using electrochemiluminescence. The sensitivity was determined on the condition that the specificity was ≥ 90%. Results: Of the 85 cases, 36 (42.4%) were malignant, 30 (35.3%) were benign, and the results were inconclusive in 19 (22.3%). In the malignant cases, the CEA and CYFRA21-1 levels were higher in the pleural fluid than in the blood, which was not observed for CA 15-3. In the benign cases, the CYFRA21-1 levels were higher in the pleural fluid than in the blood, whereas the opposite was found for CEA and CA 15-3. There were significant differences between malignant and benign cases for all markers, in pleural fluid and blood. In the pleural fluid, the sensitivity of CEA, CYFRA21-1 and CA 15-3 was 69.4, 69.4 and 66.7%, respectively, and the combined sensitivity was 80.6%. In the blood, the sensitivity was 57.1%, 71.4% and 48.6% for CEA, CYFRA21-1 and CA 15-3, respectively, and the combined sensitivity was 77%. Conclusion: The results suggest that these markers might be useful in the differentiation between malignant and benign pleural effusion.

Keywords: Biological tumor marker; Cyfra 21.1; CEA; CA 15.3; Pleural effusion.

Objective: To evaluate the pharmaceutical equivalence of a test formulation (fixed-dose combination of budesonide and formoterol fumarate in a single capsule dispensed in an Aerocaps® inhaler) in relation to a reference formulation (budesonide and formoterol fumarate in two separate capsules dispensed in an Aerolizer® inhaler). Methods: This was an in vitro study in which we performed the identification/quantification of the active ingredients by HPLC and determined dose uniformity and aerodynamic particle size distribution in the test and reference formulations. Results: In the test formulation, the content of budesonide and formoterol was 111.0% and 103.8%, respectively, compared with 110.5% and 104.5%, respectively, in the reference formulation. In the test formulation, dose uniformity regarding budesonide and formoterol was 293.2 µg and 10.2 µg, respectively, whereas it was 353.0 µg and 11.1 µg in the reference formulation. These values are within the recommended range for this type of formulation (75-125% of the labeled dose). The fine particle fraction (< 5 µm) for budesonide and formoterol was 45% and 56%, respectively, in the test formulation and 54% and 52%, respectively, in the reference formulation. Conclusions: For both of the formulations tested, the levels of active ingredients, dose uniformity, and aerodynamic diameters were suitable for use with the respective dry powder inhalers.

Keywords: : Asthma; Budesonide; Bronchodilator agents; Drug therapy, combination.

Background: The decision to drain parapneumonic pleural effusion in children is still controversial. An indicative scoring system to assess the need for chest-tube drainage arose from a partnership between pediatricians and surgeons. Objective: To evaluate the utility of the score in indicating whether drainage should be performed in pediatric patients with parapneumonic effusion. Method: A cross-sectional study involving 250 inpatients with parapneumonic effusion, treated in a tertiary-care hospital between 1994 and 1999. The following variables were analyzed: clinical presentation, chest X-rays, pleural fluid culture and biochemical analysis of the pleural fluid, as well as the score and treatment. The score was based on four categories: general appearance of the pleural fluid, chest X-rays, laboratory findings, and the second thoracentesis. Drainage was recommended for patients scoring higher than 5.5. Results: Of 941 children with pneumonia, parapneumonic effusion occurred in 304 (32.2%), 250 of which were included in the study. Of those, 146 (58.4%) were male, with mean of age of 3 years (median, 2 years). The cutoff points (determined through receiver operating characteristic curve analysis) for suggesting pleural drainage were pH < 7.29 (89.2% sensitivity and 76.5% specificity), score > 5.0 (68.7% sensitivity and 81.7% specificity). These values were more strongly correlated with the need for drainage (p = 0.001), as were those reported in the literature (pH = 7.0 and glucose < 40). The lactate dehydrogenase did not prove to be a good parameter for indicating a need for drainage. Conclusion: In addition to the purulent aspect, pH = 7.29 and score were the best indicators of the need for chest-tube drainage in pediatric patients with parapneumonic effusion. However, we suggest that some score variables be readjusted to improve the usefulness of this particular scoring system.

Keywords: Empyema. Pleural effusion. Pneumonia.

Objective: To evaluate the role of intrapleural positioning of a pleural catheter in early lung expansion and pleurodesis success in patients with recurrent malignant pleural effusion (RMPE). Methods: This was a retrospective study nested into a larger prospective cohort study including patients with RMPE recruited from a tertiary university teaching hospital between June of 2009 and September of 2014. The patients underwent pleural catheter insertion followed by bedside pleurodesis. Chest CT scans were performed twice: immediately before pleurodesis (iCT) and 30 days after pleurodesis (CT30). Catheter positioning was categorized based on iCT scans as posterolateral, anterior, fissural, and subpulmonary. We used the pleural volume on iCT scans to estimate early lung expansion and the difference between the pleural volumes on CT30 and iCT scans to evaluate radiological success of pleurodesis. Clinical pleurodesis success was defined as no need for any other pleural procedure. Results: Of the 131 eligible patients from the original study, 85 were included in this nested study (64 women; mean age: 60.74 years). Catheter tip positioning was subpulmonary in 35 patients (41%), anterior in 23 (27%), posterolateral in 17 (20%), and fissural in 10 (12%). No significant differences were found among the groups regarding early lung expansion (median residual pleural cavity = 377 mL; interquartile range: 171-722 mL; p = 0.645), radiological success of pleurodesis (median volume = 33 mL; interquartile range: −225 to 257 mL; p = 0.923), and clinical success of pleurodesis (85.8%; p = 0.676). Conclusions: Our results suggest that the position of the tip of the pleural catheter influences neither early lung expansion nor bedside pleurodesis success in patients with RMPE.

Keywords: Pleurodesis; Pleural effusion, malignant; Tomography; Catheters.

This is a prospective study of benign and malignant pleural effusions carried out to determine the diagnostic yield of standard cytopathology compared to findings of DNA ploidy obtained by flow cytometry. Twenty-six samples of pleural effusion obtained by thoracocentesis were analyzed by cytopathology and flow cytometry. Final diagnosis was confirmed in all instances by histopathology of pleural biopsies. Ten samples were excluded from the analysis due to technical reasons, and the remaining 16 were used in the study. There were 13 malignant and 3 benign pleural effusions. Cytopathology revealed 9 malignant effusions and 7 benign effusions (4 false negatives). Flow cytometry findings have shown euploid DNA content in all 3 benign effusions (positive predictive value and specificity of 100%) and in 8 malignant effusions (positive value and specificity of 100%) and in 8 malignant effusions (sensitivity of 38.4% and negative predictive value of 27.2%). Cytopathology showed specificity of 100%, sensitivity of 69.2%, and positive and negative predictive values of 100% and 42.8%, respectively. The authors concluded that in this study the low sensitivity and negative value of flow cytometry in comparison to conventional cytopathology have limited the usefulness of flow cytometry to the finding of euploid DNA contents in benign pleural effusions.

Keywords: Flow cytometry. Cytopathology. DNA ploidy. Pleural effusion.

Background: Open lung biopsy is regarded as the gold standard for the diagnosis of diffuse pulmonary infiltrates. Objective: To determine the diagnostic yield, therapeutic changes, complications and mortality attributed to open lung biopsy in patients with diffuse pulmonary infiltrates and on mechanical ventilation. Method: We reviewed, retrospectively, the charts of 24 patients, ranging from 26 to 89 years of age, admitted to the intensive care units of two private hospitals and submitted to open lung biopsy. Results: Diagnostic positivity was found in 100% of patients, resulting in an alteration in the treatment regimen in 75%. Postoperative complications occurred in five patients (20.8%). There were no biopsy-related deaths, although global mortality was 45.8%. Conclusion: Open lung biopsy is a safe and high yield procedure for diagnosing diffuse pulmonary infiltrate in patients on mechanical ventilation. Despite the fact that no mortality impact factor has been assigned to such patients, data in the literature regarding prognosis must be taken into consideration.

Keywords: Biopsy. Respiratory insufficiency. Respiration artificial.

This brief communication demonstrates the correlation of persistent respiratory symptoms with functional, tomographic, and transbronchial pulmonary biopsy findings in patients with COVID-19 who had a long follow-up period. We report a series of six COVID-19 patients with pulmonary involvement who presented with persistent dyspnea within 4-15 months of discharge. We performed transbronchial biopsies, and the histopathological pattern consistently demonstrated peribronchial remodeling with interstitial pulmonary fibrosis. Therefore, lung biopsy may be useful in the approach of patients with long COVID-19, although the type of procedure, its precise indication, and the moment to perform it are yet to be clarified. (Brazilian Registry of Clinical Trials-ReBEC; identifier: RBR-8j9kqy [http://www.ensaiosclinicos.gov.br])

Keywords: COVID-19; COVID-19/pathology; Pulmonary fibrosis; Respiratory function tests; Biopsy.

Objective: To compare equations for predicting peak quadriceps femoris (QF) muscle force; to determine the agreement among the equations in identifying QF muscle weakness in COPD patients; and to assess the differences in characteristics among the groups of patients classified as having or not having QF muscle weakness by each equation. Methods: Fifty-six COPD patients underwent assessment of peak QF muscle force by dynamometry (maximal voluntary isometric contraction of knee extension). Predicted values were calculated with three equations: an age-height-weight-gender equation (Eq-AHWG); an age-weight-gender equation (Eq-AWG); and an age-fat-free mass-gender equation (Eq-AFFMG). Results: Comparison of the percentage of predicted values obtained with the three equations showed that the Eq-AHWG gave higher values than did the Eq-AWG and Eq-AFFMG, with no difference between the last two. The Eq-AHWG showed moderate agreement with the Eq-AWG and Eq-AFFMG, whereas the last two also showed moderate, albeit lower, agreement with each other. In the sample as a whole, QF muscle weakness (< 80% of predicted) was identified by the Eq-AHWG, Eq-AWG, and Eq-AFFMG in 59%, 68%, and 70% of the patients, respectively (p > 0.05). Age, fat-free mass, and body mass index are characteristics that differentiate between patients with and without QF muscle weakness. Conclusions: The three equations were statistically equivalent in classifying COPD patients as having or not having QF muscle weakness. However, the Eq-AHWG gave higher peak force values than did the Eq-AWG and the Eq-AFFMG, as well as showing greater agreement with the other equations.

Keywords: Pulmonary disease, chronic obstructive; Muscle strength; Quadriceps muscle; Reference values.

Objective: Studies in the literature regarding the use of remdesivir to treat COVID-19 patients have shown conflicting results. This study sought to answer questions related to the use of remdesivir for the treatment of patients hospitalized with moderate to severe COVID-19. Methods: This was a systematic review and meta-analysis including phase 3 randomized clinical trials (RCTs) and observational cohort studies selected from various databases, comparing patients hospitalized with moderate to severe COVID-19 receiving remdesivir and controls. Results: A total of 207 studies were retrieved, 9 of which met the eligibility criteria and were included in the study. The meta-analysis using RCTs alone showed no statistically significant differences regarding mortality or use of mechanical ventilation/extracorporeal membrane oxygenation between remdesivir and control groups, and the quality of evidence was moderate and low, respectively. The use of remdesivir increased the recovery rate by 6% (95% CI, 3-9); p = 0.004) and the clinical improvement rate by 7% (95% CI, 1-14); p = 0.02). Additionally, no significant differences in mortality were found between remdesivir and control groups when the meta-analysis used observational cohort studies alone (risk difference = -0.01 (95% CI, -0.02 to 0.01; p = 0.32), the quality of evidence being moderate, and the risk of adverse events was 4% ([95% CI, -0.08 to 0.01]; p = 0.09). Conclusions: The use of remdesivir for the treatment of patients with moderate to severe COVID-19 had no significant impact on clinically important outcomes.

Keywords: Antiviral agents; COVID-19; SARS-CoV-2.