Objective: To propose a new classification criterion for the differentiation between pleural exudates and transudates-quantifying total proteins in pleural fluid (TP-PF) and lactate dehydrogenase in pleural fluid (LDH-PF) exclusively-as well as to compare this new criterion with the classical criterion in terms of diagnostic yield. Methods: This was an observational, cross-sectional study with a within-subject design, comprising 181 patients with pleural effusion treated at two university hospitals in the state of Rio de Janeiro, Brazil, between 2003 and 2006. The diagnostic parameters included in the classical criterion were identified, as were those included in the new criterion. Results: Of the 181 patients, 152 and 29 were diagnosed with pleural exudates and pleural transudates, respectively. For the classical criterion, the sensitivity, specificity, and accuracy for the diagnosis of pleural exudates were, respectively, 99.8%, 68.6%, and 94.5%, whereas the corresponding values for the diagnosis of pleural transudates were 76.1%, 90.1%, and 87.6%. For the new criterion (cut-off points set at 3.4 g/dL for TP-PF and 328.0 U/L for LDH-PF), the sensitivity, specificity, and accuracy for the diagnosis of exudates were, respectively, 99.4%, 72.6%, and 99.2%, whereas the corresponding values for the diagnosis of transudates were 98.5%, 83.4%, and 90.0%. The accuracy of the new criterion for the diagnosis of pleural exudates was significantly greater than was that of the classical criterion (p = 0.0022). Conclusions: The diagnostic yield was comparable between the two criteria studied. Therefore, the new classification criterion can be used in daily practice.

Keywords: Pleural effusion/diagnosis; Pleural effusion/classification; Exudates and transudates.

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: Mometasone furoate (MF) is a new potent synthetic inhaled corticosteroid. Internationally, MF is administered via a dry-powder inhaler that contains multiple doses. As a preparation that would be more cost-effective, single-dose MF capsules were developed in Brazil. The objective of the present study was to evaluate the efficacy and safety of the two inhalers for MF administration in patients with asthma. Methods: A randomized, multicenter, open-label, parallel-group clinical trial involving 74 adult patients with moderate persistent asthma who were randomized into two groups to receive approximately 400 µg of MF once a day for 60 days, either via the multiple-dose inhaler or via the newly developed single-dose inhaler. Results: No significant differences were observed between the two groups regarding the primary endpoints (FEV1 and rescue medication use) or the secondary endpoints (morning PEF, tolerability, and safety, the last as assessed on the basis of hypothalamic-pituitary-adrenal axis function). Conclusions: The use of the single-dose inhaler developed in Brazil for MF administration is as effective and safe as is that of a standard inhaler in the treatment of patients with asthma. Keywords: Anti-asthmatic agents; Pregnadienediols; Metered dose inhalers.

Keywords: Anti-asthmatic agents; Pregnadienediols; Metered dose inhalers. (ClinicalTrials.gov identifier: NCT00975741 [http://www.clinicaltrials.gov/])