Maria Elena Guariento

Use of a nested polymerase chain reaction (N-PCR) to detect Trypanosoma cruzi in blood samples from chronic chagasic patients and patients with doubtful serologies

Chagas disease, caused by Trypanosoma cruzi, is an important endemic illness in Latin America. Serologic tests for T. cruzi detection in blood are sensitive, but their specificity is unsatisfactory. Direct detection of parasites in blood, either by xenodiagnosis or hemoculture, is highly specific but of low sensitivity. Molecular assays such as the Polymerase chain reaction (PCR), which amplifies certain repetitive sequences of nuclear DNA has been used as a good alternative tool for T. cruzi detection in human blood. The present study aimed to test PCR diagnosis in chagasic chronic patients and doubtful serologic patients attended in GEDOCH (Chagas Disease Study Group/UNICAMP, Brazil). A 149 bp fragment originated from nuclear DNA was specifically detected in chronic chagasic patients. The results of these tests were compared with serologic diagnosis performed using standard techniques and xenodiagnosis. We found that 43 out of 50 patients previously serodiagnosed as chagasic were positive using the N-PCR method. Thirteen of 30 patients with doubtful serologic results were confirmed as positive by N-PCR. Our results suggest that the N-PCR may be a complementary tool to serology in the diagnosis of Chagas disease, and that it is usefull for parasite detection in patients with chronic disease and patients with doubtful serologic results.

Trypanosoma cruzi: parasite persistence in tissues in chronic chagasic Brazilian patients

Chagas disease in the chronic phase may develop into cardiac and/or digestive forms. The pathogenesis of the disease is not yet clear and studies have been carried out to elucidate the role of parasite persistence in affected organs. The aim of this study was to detect and quantify Trypanosoma cruzi in paraffin-embedded tissue samples from chronic patients using NPCR (nested polymerase chain reaction) and QPCR (quantitative polymerase chain reaction) methods. These results were correlated to anatomopathological alterations in the heart and gastrointestinal tract (GIT). Of the 23 patients studied, 18 presented the cardiac form and five presented the cardiodigestive form of Chagas disease. DNA samples were randomly isolated from formalin-fixed paraffin-embedded sections of heart and GIT tissue of 23 necropsies and were analyzed through NPCR amplification. T. cruzi DNA was detected by NPCR in 48/56 (85.7%) heart and 35/42 (83.3%) GIT samples from patients with the cardiac form. For patients with the cardiodigestive form, NPCR was positive in 12/14 (85.7%) heart and in 14/14 (100%) GIT samples. QPCR, with an efficiency of 97.6%, was performed in 13 samples (11 from cardiac and 2 from cardiodigestive form) identified previously as positive by NPCR. The number of T. cruzi copies was compared to heart weight and no statistical significance was observed. Additionally, we compared the number of copies in different tissues (both heart and GIT) in six samples from the cardiac form and two samples from the cardiodigestive form. The parasite load observed was proportionally higher in heart tissues from patients with the cardiac form. These results show that the presence of the parasite in tissues is essential to Chagas disease pathogenesis.

Quality of life and depressive symptoms in Chagas disease patients.

BackgroundBesides the typical organic aspects of Chagas disease, the patients need to face physical, psychological, social and economic difficulties, which can compromise their quality of life. Consequently they may develop feelings of sadness, grief and loss, and depressive symptoms.MethodsThis study assessed the quality of life and depressive symptoms in 110 Chagas disease patients using WHOQOL-BREF for measuring the quality of life; also it was used Beck Depression Inventory (BDI) for depressive symptom evaluation.ResultsAmong all patients, 51% were women; 42.5% considered their quality of life as positive and 40.9% presented depressive symptoms. Chagas disease clinical form distribution was: cardiac 49.09%, indeterminate 26.36%, digestive 12.73%, and mixed 11.82%. There was no significant difference comparing the depressive symptom intensity on gender, age and marital status, although there was a significant difference comparing depressive symptoms in indeterminate clinical form patients with others. All domains of WHOQOL-BREF showed significant correlation coefficients (Pearson).ConclusionsAt digestive form it was reported minor scores in the quality of life domains and greater ones on depressive symptom levels. There was a negative correlation between BDI and WHOQOL-BREF, suggesting that, among Chagas disease patients, the higher is the quality of life the lower is the intensity of depressive symptoms.

Relações entre o bem-estar subjetivo e a funcionalidade em idosos em seguimento ambulatorial

OBJECTIVE: The aim of this study was to investigate the relationship between subjective well-being, functional independence and lower-limb performance (muscle strength, gait velocity and balance) among elderly people undergoing outpatient follow-up, stratified by sex and age groups. METHODS: We evaluated 125 elderly people, aged 60 years and over, who received care at a geriatric outpatient clinic. The instruments used were: 1) Functional Independence Measure (FIM) to evaluate functional dependence; 2) Short Physical Performance Battery (SPPB) to measure physical performance; and 3) Subjective Well-Being (SWB) with questions about health and satisfaction with life. RESULTS: A convenience sample was used, with predominance of females (who had greater functional impairment). The Spearman correlation coefficients for subjective well-being and the performance tests varied from -0.16 to 0.31 for men and -0.09 to 0.29 for women, therefore there were no differences between the sexes. However, the older participants had a higher level of satisfaction than the younger participants. Perceived health was also more satisfactory among the older participants, however comparative perceived health was better among the elderly participants with moderate to good physical performance. CONCLUSION: The results suggest that older individuals have greater satisfaction with life and better perceived health. Moreover, good physical performance was an important variable for better perceived health when compared to other people.

Relationship between lower-limb muscle strength and frailty among elderly people

CONTEXT AND OBJECTIVE Sarcopenia is the main factor involved in the development of frailty syndrome. The aims here were to investigate relationships between lower-limb muscle strength and the variables of sex, age and frailty criteria; compare lower-limb muscle strength with each frailty criterion; and assess the power of each criterion for estimating the risk of frailty among elderly outpatients. DESIGN AND SETTING Cross-sectional study at the Geriatrics Outpatient Clinic of a university hospital in Campinas. METHOD A non-probabilistic convenience sample of 150 elderly people of both sexes who were followed up as outpatients was assessed. Sociodemographic data (sex and age) and physical health data (frailty criteria and the five-times sit-to-stand test) were gathered. Descriptive, comparative and multivariate logistic regression analyses were performed. RESULTS The majority of the elderly people (77.3%) were 70 years of age or over, with predominance of females (64.2%) and had a low score for the five-times sit-to-stand test (81.4% scored 0 or 1); 55.3% of the elderly people presented three or more frailty criteria. A significant association was found between lower-limb muscle strength and the variables of age and number of frailty criteria. CONCLUSIONS Lower levels of lower-limb muscle strength were associated with advanced age and greater presence of signs of frailty. Moreover, lower-limb muscle strength was also associated with the criteria of reduced walking speed criteria and hand-grip strength.

Biologia do envelhecimento: teorias, mecanismos e perspectivas

Abstract The article reviews the major biological theories of aging, and discusses the most relevant mechanisms to explain the aging process. It begins with the evolutionary theories, explores the molecular-cellular mechanisms, and presents the perspective of the systemic theories. The complex etiology of aging is a challenge to the researchers. The knowledge on that phenomenon develops towards an integrative approach.

Influence of blood pressure profile on frailty phenotype in community-dwelling elders in Brazil - FIBRA study.

Frailty is a clinical condition associated with pathological aging and biological vulnerability. In the spectrum of events related to frailty, aging of the cardiocirculatory system and abnormalities in arterial blood pressure (BP) partly explain the changes in tissue perfusion and, potentially, the decrease in physiological reserves. This study investigated the relationship between BP levels, systemic arterial hypertension (SAH) and the frailty phenotype by analyzing frailty criteria in a cross-sectional model into the FIBRA network, a populational sample of community-dwelling elders in Southeastern Brazil. Study participants with ≥65 years were selected by probabilistic sampling of residents in the urban area of the municipality of Campinas (n=900). Considering frailty as a whole and the difference between genders, there was a greater proportion of frail or pre-frail individuals among women than men. Analysis of individual frailty criteria showed that weight loss and fatigue were more common among women (18.3% vs. 12.5%, p=0.034 and 22.5% vs. 11.9%, p<0.001, respectively). Comparison of individuals with or without SAH failed to reveal any differences related to frailty criteria. Nevertheless, averages of diastolic blood pressure (DBP) and mean arterial blood pressure values were lower among elderly individuals with reduced grip strength, physical activity and the frailty classification as a whole (OR 0.986, IC 0.975-0.997) (for every 1 mmHg reduction in MBP values, the likelihood of being frail increased 1.4%). Our findings corroborate the relationship between BP values and frailty in the elderly and contribute to an understanding of the pathophysiological mechanisms of the syndrome.

Serological profiles and evaluation of parasitaemia by PCR and blood culture in individuals chronically infected by Trypanosoma cruzi treated with benzonidazole

Objective  To evaluate the serological and parasitological status of patients with chronic Chagas disease (CD) after chemotherapy with benzonidazole.

Chronotopic and blood pressure response to oral glucose load in chagas' disease

Cardiac chronotropic and pressor responses after an oral load of glucose were assessed in sixteen Chagasic subjects and 28 controls by means of blood pressure and pulse rate measurements. Cardiovascular response was correlated with serum insulin and glucose levels. The experiment identified a subgroup of Chagasic subjects (n = 8) with a hypoinsulinemic behavior presenting less chronotropic and pressor responses than controls. This may indicate a lower insulin activity and/or an early Autonomic Nervous System dysfunction in this subgroup.

Evolução fatal da co-infecção doença de Chagas/Aids: dificuldades diagnósticas entre a reagudização da miocardite e a miocardiopatia chagásica crônica

Chagas disease is a type of parasitosis caused by the protozoan Trypanosoma cruzi, and it is transmitted by triatomine insects. This disease is found between the southern United States to Argentina and approximately 14 million people in Latin America are believed to be infected, predominantly with the chronic form of the disease. Reactivation of Chagas disease can occur among immunosuppressed patients, as has been observed among AIDS patients. In one such case, we observed cardiac decompensation with severe ventricular dysfunction and arrhythmias. This case was thought to be reactivation of Chagas disease in the myocardium, since the xenodiagnosis was positive. Specific treatment for Trypanosoma cruzi was administered, consisting of benznidazole, but the course of treatment was not completed because the patient died due to cardiopathic complications. The necropsy showed the usual stigmas of chronic Chagas cardiopathy, such as fibrosing myocarditis and a decreased number of neurons in the digestive system. There were no amastigote forms of Trypanosoma cruzi in any of the tissue samples studied. Therefore, reactivation of Chagas disease was not demonstrated but, rather, the natural evolution of chronic Chagas cardiopathy was demonstrated.