Biomedical subjects

M L Antunes

Publications and source records attributed to M L Antunes.

At least 19 recordsLinked to original sources

PubMed2001

Determinants of drug-resistant tuberculosis: analysis of 11 countries.

SETTING: Eleven countries/territories. OBJECTIVES: Global information on the determinants of drug-resistant tuberculosis (TB) based on representative data is not available. We therefore studied the relationship between demographic characteristics, prior TB treatment, and human immunodeficiency virus (HIV) infection with anti-tuberculosis drug resistance. METHODS: Population-based representative data on new and previously treated patients with TB collected within an international drug resistance surveillance network. RESULTS: Of 9,615 patients, 8,222 (85.5%) were new cases of TB and 1,393 (14.5%) were previously treated cases. Compared with new cases, previously treated cases were significantly more likely to have resistance to one (OR = 2.5,95% CI 2.1-3.0; P < 0.001), two (OR = 4.6, 95%CI 3.7-5.6; P < 0.001), three (OR = 11.5, 95%CI 8.6-15.3; P < 0.001), and four (OR = 18.5, 95% CI 12.0-28.5; P < 0.001) drugs. An approximately linear increase in the likelihood of having multidrug-resistant tuberculosis (MDR-TB) was observed as the total time (measured in months) of prior anti-tuberculosis treatment increased (P < 0.001, chi2 for trend). In multivariate analysis, prior TB treatment for 6-11 months (OR = 7.6, 95% CI 2.6, 22.4; P < 0.001) and > or = 12 months (OR 13.7, 95% CI 4.5-41.6; P < 0.001), but not HIV positivity, was associated with MDR-TB. CONCLUSION: This study shows that prior but ineffective treatment is a strong predictor of drug resistance, and that HIV is not an independent risk factor for MDR-TB. The association between length of treatment and drug resistance may reflect longer treatment as a result of treatment failure in patients with drug resistance; it may also reflect irregular prior treatment for TB, leading to drug resistance.

Adolescent↗

PubMed2000

Anti-tuberculosis drug resistance in Portugal.

SETTING: A survey based upon a representative sample of smear-positive pulmonary tuberculosis patients was undertaken in Portugal, as part of the World Health Organization's Global Project on Anti-Tuberculosis Drug Resistance Surveillance. OBJECTIVE: To determine the level of primary antituberculosis drug resistance at both national and regional levels, and to assess its relative weight within the performance of the National Tuberculosis Programme (NTP). DESIGN: Mycobacterium tuberculosis isolates from 1,105 patients with smear-positive pulmonary tuberculosis admitted to 46 randomly stratified treatment centres all over mainland Portugal were submitted to susceptibility testing with four drugs. Human immunodeficiency virus (HIV) testing was included in the patients' evaluation scheme. RESULTS: Of the strains isolated, 197 (17.8%) were resistant to at least one drug. Primary resistance to isoniazid was 7.7% and to rifampicin 1.9%. Acquired drug resistance was 39.2% in total, any acquired resistance to isoniazid 31.1% and to rifampicin 20.9%. Primary multidrug resistance (MDR) was 1.8% and acquired MDR was 20.9%. HIV testing was positive in 29.2% of MDR-TB cases. CONCLUSIONS: Drug resistance in Portugal is high. Primary MDR and particularly acquired MDR occur in a high proportion of cases, indicating a need for improvement in NTP performance.

Adolescent↗

PubMed1995

Thallium-201 lung uptake and peak treadmill exercise first-pass ejection fraction.

Increased thallium-201 lung uptake immediately after exercise has been shown (1) to be a marker for extensive coronary artery disease, (2) to correlate with low rest and exercise left ventricular ejection fraction by supine gated blood pool scintigraphy, and (3) to be a powerful independent predictor of future cardiac events. Exercise left ventricular ejection fraction measured during upright exercise by the first-pass technique has also been shown to be a powerful independent prognostic variable. Combined perfusion and exercise left ventricular ejection fraction can be acquired by using the technetium 99m-based myocardial perfusion agents and offers an alternative protocol to stress/redistribution thallium imaging. It is therefore clinically important to understand the relation between exercise lung heart thallium uptake and exercise left ventricular ejection fraction. Accordingly, both these measurements were acquired in 38 patients with documented coronary artery disease who underwent two treadmill exercise studies. Parameters obtained from the first-pass study that are known to affect lung thallium uptake were correlated with exercise lung/heart thallium ratios; lung/heart ratios were used in a model to predict exercise left ventricular ejection fraction values. Exercise left ventricular ejection fraction and peak filling rate showed significant negative correlations with thallium lung/heart ratio, but the first-pass variables examined were not independently predictive of thallium lung uptake. The chance of finding an abnormal thallium lung/heart ratio at exercise LVEF of 40% is only 52%, whereas the chance of finding an abnormal ratio at exercise LVEF of 30% is 74%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

[Tuberculosis. The world outlook].

Three cases of tuberculosis (TB), paradigmatic of the current situation are presented. The world TB situation is described, according to the latest figures from WHO: There is a reduction in Europe and the American regions and an increase more marked in South East Asia, followed closely by the Western Pacific and the African regions. The global increase in cases was 21%. Future perspectives are drawn and the WHO strategies, made public in 1994, are outlined.

AIDS-Related Opportunistic Infections↗

PubMed1992

Diagnosis of right ventricular acute myocardial infarction by dual isotope thallium-201 and indium-111 antimyosin SPECT imaging.

To assess the diagnostic value of indium-111 antimyosin for detecting right ventricular (RV) wall acute infarction, 30 patients with electrocardiographic-documented left ventricular inferior (posterior) wall acute myocardial infarction underwent simultaneous dual isotope indium-111 antimyosin and thallium-201 single-photon emission computed tomography (SPECT) within 2 days of admission. RV necrosis was defined as uptake of indium-111 antimyosin anterior and to the right of septal thallium uptake. Twenty-nine of the 30 patients (97%) had indium-111 antimyosin uptake in the inferior, posterior or lateral walls of the left ventricle and 14 of 30 (47%) had additional RV antimyosin uptake. Three different patterns of RV uptake of indium-111 antimyosin were observed: crescent-shaped, focal and apical. Twenty-seven patients underwent gated blood pool scanning before hospital discharge. Twelve of the 14 patients with RV antimyosin uptake had gated blood pool scintigraphy and 7 of 12 had RV dysfunction; 5 had normal RV function. Except for 1 patient who had questionable RV antimyosin uptake and had RV dysfunction, no patient without RV antimyosin uptake had RV dysfunction. In summary, right and left ventricular necrosis can be detected on tomographic images of indium-111 antimyosin uptake in patients with inferior infarctions when simultaneous uptake of a perfusion tracer, thallium-201, is imaged and used as an aid to reconstruction and anatomic localization.

Adult↗

PubMed1992

Tuberculosis surveillance and evaluation system in Portugal.

Tuberculosis is an important public health problem in Portugal, so a new and improved computerized programme for the surveillance and evaluation of tuberculosis data was set up to obtain more precise information of relevant epidemiological indices, besides helping clinicians and regional coordinators to evaluate the local situation, such as clinical features, results of treatment and surveillance of failures and abscondings. Data stored on the computer is described in detail. The evolution of the incidence of tuberculosis is presented, together with more detailed figures for 1990. These figures were obtained with the former, cruder process. The present system is now being deployed and checked, after 1 year's trial and evaluation by some of its users. Its results will be presented in a future publication.

Databases, Factual↗

PubMed1991

Effect of infarct size measured from antimyosin single-photon emission computed tomographic scans on left ventricular remodeling.

To evaluate the effect of infarct size on left ventricular volumes and geometric remodeling, 26 patients with a first acute Q wave myocardial infarction (anterior in 14, inferior in 12) had the infarct sized from single-photon emission computed tomographic (SPECT) imaging of indium-111 antimyosin. All patients underwent gated blood pool scintigraphy before hospital discharge for determination of ejection fraction and end-diastolic and end-systolic volume indexes. Infarct size was quantitated from indium-111 antimyosin uptake in coronal slices with use of a threshold technique for edge detection. Nineteen of 26 patients had additional simultaneous acquisitions of indium-111 and thallium-201 uptake and the infarct was expressed as a percent of the total left ventricle. Infarct size was larger (59 +/- 16 vs. 33 +/- 16 g), predischarge ejection fraction lower (35 +/- 5% vs. 60 +/- 9%) and end-systolic volume index higher (57 +/- 13 vs. 36 +/- 10 ml/m2) in the group with anterior infarction. Despite these differences, predischarge end-diastolic volume index was not significantly different between the group with anterior (88 +/- 17 ml/m2) versus inferior (89 +/- 14 ml/m2) infarction. There was a significant inverse correlation between percent infarct size and ejection fraction for patients with dual isotope imaging (r = -0.90) and a significant direct correlation between infarct size and end-systolic volume index (r = 0.79, p less than 0.01). Fourteen patients without subsequent myocardial infarction or coronary artery bypass grafting had a repeat gated blood pool study late (26 +/- 15 months) after infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Measurement of acute Q-wave myocardial infarct size with single photon emission computed tomography imaging of indium-111 antimyosin.

Myocardial infarct size was measured by single photon emission computed tomography (SPECT) following injection of indium-111 antimyosin in 27 patients (18 male and 9 female; mean age 57.4 +/- 10.5 years, range 37 to 75) who had acute transmural myocardial infarction (MI). These 27 patients represent 27 of 35 (77%) consecutive patients with acute Q-wave infarctions who were injected with indium-111 antimyosin. In the remaining 8 patients either tracer uptake was too faint or the scans were technically inadequate to permit infarct sizing from SPECT reconstructions. In the 27 patients studied, infarct location by electrocardiogram was anterior in 15 and inferoposterior in 12. Nine patients had a history of prior infarction. Each patient received 2 mCi of indium-111 antimyosin followed by SPECT imaging 48 hours later. Infarct mass was determined from coronal slices using a threshold value obtained from a human torso/cardiac phantom. Infarct size ranged from 11 to 87 g mean 48.5 +/- 24). Anterior infarcts were significantly (p less than 0.01) larger (60 +/- 20 g) than inferoposterior infarcts (34 +/- 21 g). For patients without prior MI, there were significant inverse correlations between infarct size and ejection fraction (r = 0.71, p less than 0.01) and wall motion score (r = 0.58, p less than 0.01) obtained from predischarge gated blood pool scans. Peak creatine kinase-MB correlated significantly with infarct size for patients without either reperfusion or right ventricular infarction (r = 0.66). Seven patients without prior infarcts had additional simultaneous indium-111/thallium-201 SPECT studies using dual energy windows.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Long-term function of human cardiac allografts assessed by two-dimensional echocardiography.

Previous studies from our laboratory demonstrated increasing left ventricular mass in cyclosporine-treated cardiac allograft recipients over 30 days after transplantation, but the long-term evolution of this process and possible effects on allograft function are unknown. Accordingly, quantitative two-dimensional echocardiography was performed 2 and 23 days and 15 months postoperatively in 14 recipients treated with cyclosporine and prednisone. Changes in left ventricular ejection fraction, end-diastolic volume, mass, and end-systolic wall stress were analyzed. Comparison of studies at 2 and 23 days revealed significant (p less than 0.01) increases in ejection fraction (54% +/- 8% [standard deviation] to 62% +/- 4%), end-diastolic volume (84% +/- 32 ml to 96 +/- 31 ml), and left ventricular mass (118 +/- 45 gm to 136 +/- 41 gm). Comparison of studies at 23 days and 15 months revealed no significant change in end-diastolic volume or left ventricular mass, whereas ejection fraction decreased slightly (62% +/- 4% to 57% +/- 4%, p less than 0.01). End-systolic wall stress decreased when data at 2 days and 15 months were compared (83 +/- 24 gm/cm2 versus 66 +/- 18 gm/cm2, p less than 0.05), but no change in contractility was apparent from the ejection fraction/end-systolic stress relation. We conclude that left ventricular mass and end-diastolic volume increase early after transplantation in cyclosporine-treated cardiac allograft recipients, but these changes are not predictive of long-term results, which are characterized by no significant late variation in left ventricular mass, end-diastolic volume, or contractility.

Adolescent↗

PubMed1988

Effect of electrophysiological testing on ejection fraction during cardioverter/defibrillator implantation.

To evaluate the effect of repeated induction of ventricular tachycardia or ventricular fibrillation, or both, in patients with poor left ventricular function, we performed intraoperative two-dimensional echocardiography in 6 patients undergoing implantation of the automatic implantable cardioverter/defibrillator. Changes in left ventricular ejection fraction in sinus rhythm were assessed before the first inducible ventricular arrhythmia and after a mean of 6 +/- 1.9 (SD) episodes of ventricular tachycardia or ventricular fibrillation. During the procedure no significant change in mean ejection fraction was observed (28 +/- 14 versus 27 +/- 17%). Only 1 of the 6 patients studied had a change in ejection fraction greater than 3% (a decrease from 20 to 11%). In an overall clinical series of 38 primary implants or generator changes (including electrophysiological testing) in 29 patients, 1 patient recovered after postoperative inotropic support and 1 died of acute postoperative ischemic heart failure. We conclude that ventricular arrhythmias induced during automatic implantable cardioverter/defibrillator implantation have no immediate deleterious effects on ejection fraction in most patients with compromised left ventricular function and without ongoing ischemia.

Aged↗

PubMed1969