Ricardo Marques Dias

Predictive model for the diagnosis of tuberculous pleural effusion

This study developed a predictive model to identify pleural tuberculosis. A consecutive cases study of patients investigating the cause of pleural effusion, in an area of high prevalence of tuberculosis (Rio de Janeiro, Brazil). Clinical and laboratory variables were compared among patients with tuberculosis (TB) and without tuberculosis (NTB), individually and using logistic regression. The performance was described as diagnostic accuracy, compared to a gold standard in a masked way. We have studied 104 TB patients, 41 with malignant, 29 transudates, 28 parapneumonic, 13 with miscellaneous diseases. After identification of individual discrimination power aided by clinical, radiological and laboratory variables, the following ones were included in a multivariate analysis: ADA, total leukocytes, percentile of lymphocytes, protein, lactate dehydrogenase, duration of disease, age and gender. A logistic regression model to predict pleural tuberculosis including the five first variables showed the best performance. A receiver operating characteristic curve identified the best cutoff at 0.7, resulting in a sensitivity and specificity of more then 95%. The predictive model improved the specificity of ADA alone, keeping its sensitivity. This model seems helpful when a microbiological or histological diagnosis of pleural tuberculosis could not be established. External validation of these results is necessary before recommendation for routine application.

Rendimento de variáveis clínicas, radiológicas e laboratoriais para o diagnóstico da tuberculose pleural

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 well-developed continuous variable showed an LR+ > 10 and an LR- 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%).

Is it useful to perform carbon monoxide diffusion capacity and respiratory muscle function tests in patients with multiple sclerosis without disability

Background and objective:  Impairment of respiratory function has been described in end‐stage multiple sclerosis (MS), as well as in patients with mild to severe disability. No data are available regarding the respiratory function of MS patients without disability. The objective of this study was to assess the pulmonary function, respiratory muscle strength and carbon monoxide diffusion capacity of the lungs (DLCO) in patients with relapsing‐remitting multiple sclerosis (RRMS) without disability.

Does fatigue occur in MS patients without disability

Background: Motor dysfunction and fatigue are the most common impairments that are associated with multiple sclerosis (MS). Walk tests and scales demonstrate the presence of fatigue in patients with MS with different levels of disability. Objective: To evaluate objective and subjective fatigue in MS patients without disability. Methods: Were selected MS patients with relapsing remitting clinical course, from 18 to 55 years old and EDSS 0 to 1.5; controls were paired for age, gender, body mass index, and physical activity level. Fatigue caused by pulmonary diseases, anemia, diabetes, thyroid disease, psychiatry diseases (except depression), and orthopedic and rheumatologic diseases are excluded. All participants performed the 6-minute walk test (6MWT), the MS Functional Composite (MSFC), and completed the Modified Fatigue Impact Scale (MFIS) and the Beck Depression Inventory. A multivariate model was applied to identify the variables associated with fatigue. Results: 54 individuals were selected (31 patients; 23 controls). In the MSFC and 6MWT, no significant difference was observed between the groups. A MFIS total score indicated fatigue in 35% of the patients, 42% in the physical domain, 25.8% in the cognitive domain, and 29% in the psychosocial domain, which differed from the controls in all comparisons. Fatigue was associated with MS, low-physical activity, and mood disorders. Conclusions: Fatigue occurs in patients with MS in the absence of motor dysfunction and is associated with the disease itself, the sedentary lifestyle, and mood disorders. The 6MWT is not useful to demonstrate motor fatigue in subjects without neurological disability.

Which functional parameters can help differentiate severe asthma from COPD

The aim of this study was to identify the respiratory function parameters that help in the accurate diagnosis of asthma and COPD. We studied 20 asthma and 30 COPD patients who underwent lung function tests including spirometry and plethysmography both with bronchodilator test and diffusion with carbon monoxide (DLCO). The tests were performed according to International Guidelines (ATS/ERS). The asthma patients were younger (mean age = 48) than those in the COPD group (mean age = 59) and this group also had more female patients (65%) than the COPD group (40%). The results showed a more severe obstruction in the asthma group: FEV1/FVC= 59% versus 66% for COPD. There was also a greater bronchodilator response as shown by changes in absolute and percentage values for FEV1 in the asthma group. Average DLCO values were normal in the asthma group (103%P) and lower in the COPD (69%). In plethysmography the asthma group had a higher residual volume (%P) and a higher airway resistance. We concluded that many functional parameters were useful in distinguishing the asthma and COPD groups. In individual analysis, DLCO was the parameter which best aided in an accurate diagnosis in both groups, with a higher specificity for COPD. The bronchodilator response measured by changes in FEV1 showed a higher sensitivity for asthma. Thus, these two tests are highlighted in the differential diagnosis of obstructive diseases.

Hiperreactividade brônquica na sarcoidose

The purpose of this study was to measure airway responsiveness in patients with sarcoidosis using bronchoprovocation test with methacholine (BPT) in comparison to roentgenographic findings, respiratory symptoms, activity and duration of the disease. There were 17 patients with Sarcoidosis, 20 asthmatics and 21 assymptomatics. We used the tidal breathing method with standardizes output for the nebulizers. We administered increasing and successively concentrations of methacholine beginning with 0.125 to 16 mg/ml. The responses were measured by changes in FEV1 or the final concentration was reached. The results were expressed as the concentration of methacholine causing 20% fall in FEV1 (PC20). Aerosolized bronchodilator was given at the completion of all tests. There were 4 patients with sarcoidosis who had positive BPT, 3 of them with PC20<8 mg/ml associated with respiratory symptoms, bilateral hilar adenopathy, more than twoyear duration and active disease. All the asthmatic subjects had positive BPT with CP20<8 mg/ml. The entire assymptomatic group had negative BPT. Positive bronchodilator response was reached in 6 patients with sarcoidosis, 20 asthmatics and 8 assymptomatic subjects. We concluded that: (a) airway responsiveness can be reached in 17.6% patients with sarcoidosis related to bilateral hilar adenopathy, chronic and active disease; (b) 50% of sarcoidosis patients with cough and/or wheeze had positive BPT, (c) the BPT was able to discriminate asthmatic from assymptomatic subjects. Rev Port Pneumol 2005; XI (2): 97-110

Alterações ecocardiográficas em doentes asmáticos

Introduction: Asthma is a chronic inflammatory disease which has increased during the last 20 years, putting a strain on medical resources, particularly severe forms of the disease. Treatment in such cases is inhaled corticosteroids and beta agonist drugs that can produce a range of side effects. The aim of this study is to identify echocardiograph abnormalities and correlate them with severity of disease. Methodology: Eight-seven outpatients were selected at the asthma unit of the Gaffree Guinle University Hospital (HUGG). Each patient underwent spirometry, electrocardiogram (ECG) and echocardiogram (ECO) during the trial within a month maximum. Echocardiograph abnormalities found related to degree of asthma. Statistical analysis was made by non-parametric tests. Results: We found significant differences (p ≤ 0.05) for age, disease duration and haemoglobin saturation (SaO2) between the moderate and severe groups. In the sample a high prevalence of tricuspid insufficiency (41.4%) was identified. Conclusions: ECO identified a series of abnormalities that were not always dependent on severity of disease. ECO can identify pulmonary hypertension through calculation of mean pressure of the pulmonary artery. Rev Port Pneumol 2008; XIV (3): 363-377

Echocardiograph alterations in asthma patients

INTRODUCTION Asthma is a chronic inflammatory disease which has increased during the last 20 years, putting a strain on medical resources, particularly severe forms of the disease. Treatment in such cases is inhaled corticosteroids and beta agonist drugs that can produce a range of side effects. The aim of this study is to identify echocardiograph abnormalities and correlate them with severity of disease. METHODOLOGY Eight-seven outpatients were selected at the asthma unit of the Gaffrée Guinle University Hospital (HUGG). Each patient underwent spirometry, electrocardiogram (ECG) and echocardiogram (ECO) during the trial within a month maximum. Echocardiograph abnormalities found related to degree of asthma. Statistical analysis was made by nonparametric tests. RESULTS We found significant differences (p<or=0.05) for age, disease duration and haemoglobin saturation (SaO2) between the moderate and severe groups. In the sample a high prevalence of tricuspid insufficiency (41.4%) was identified. CONCLUSIONS ECO identified a series of abnormalities that were not always dependent on severity of disease. ECO can identify pulmonary hypertension through calculation of mean pressure of the pulmonary artery.

Comparison between total lung capacity and residual volume values obtained by pletysmography and single breath methods with methane.

We analyzed pulmonary function tests of twenty asthmatic patients from Gaffrée e Guinle University Hospital, classified according to Brazilian Guidelines for Asthma (2002), similar to GINA, into mild persistent or moderate (9) or severe (11) asthma. We obtained parameters from spirometry, plethysmograph (PL) and single breath technique for diffusion capacity (SB), with methane. Total lung capacity and residual volume were called TLC(PL) and RV(PL) when measured by pletysmography and TLC(SB) and RV(SB) when determined by single breath test. There were 13 women and 7 men with mean age of 47.6 years. The pulmonary dysfunction degree to FEV1/FVC was 58.8% with CI95=53.9 to 63.6. The mean values in litres for TLC(PL) (5.94) and RV(PL) (2.55) were significantly higher than for TLC(SB) (4.73) and RV(SB) (1.66). Multiple regression equations were determined for TLC(PL) e RV(PL) using only single breath values, TLC(SB) or RV(SB), and spirographic para- meters, with significant regression coefficients. However, the inclusion of spirometric parameters, except for FVC, did not improve the predicted capacity for the equations. Considering only the TLC(SB), r(2)=0.79, the equation is: TLC(PL)=(TLC(SB) *1.025)+1.088, with EPE=0.64. The regression for RV(PL), r(2) =0.23, is: RV(PL)=(RV(SB) *0.9268)+1.012. The results obtained after bronchodilation with 400 mcg of salbutamol did not improve the regression. We concluded that the SB technique did not obtain the same results as pletysmography for TLC and RV, but for TLC this difference can be predicted.