Drug and multidrug resistance among Mycobacterium leprae isolates from Brazilian relapsed leprosy patients.

Skin biopsy samples from 145 relapse leprosy cases and from five different regions in Brazil were submitted for sequence analysis of part of the genes associated with Mycobacterium leprae drug resistance. Single nucleotide polymorphisms (SNPs) in these genes were observed in M. leprae from 4 out of 92 cases with positive amplification (4.3%) and included a case with a mutation in rpoB only, another sample with SNPs in both folP1 and rpoB, and two cases showing mutations in folP1, rpoB, and gyrA, suggesting the existence of multidrug resistance (MDR). The nature of the mutations was as reported in earlier studies, being CCC to CGC in codon 55 in folP (Pro to Arg), while in the case of rpoB, all mutations occurred at codon 531, with two being a transition of TCG to ATG (Ser to Met), one TCG to TTC (Ser to Phe), and one TCG to TTG (Ser to Leu). The two cases with mutations in gyrA changed from GCA to GTA (Ala to Val) in codon 91. The median time from cure to relapse diagnosis was 9.45 years but was significantly shorter in patients with mutations (3.26 years; P = 0.0038). More than 70% of the relapses were multibacillary, including three of the mutation-carrying cases; one MDR relapse patient was paucibacillary.

Prognostic value of exercise-induced ventricular arrhythmia in Chagas' heart disease.

OBJECTIVE: To determine the prevalence and the prognostic value of exercise-induced ventricular arrhythmia (EIVA) in chronic Chagas' heart disease. STUDY DESIGN AND SETTING: An open prospective cohort of 130 clinically stable patients at a University Hospital outpatient unit in Rio de Janeiro, Brazil, was followed up at scheduled clinical visits from 1990 through 2007. The endpoint was total cardiovascular mortality. Survival curves (Kaplan-Meier) and a multivariate Cox proportional hazard model were adjusted to determine the association between EIVA and mortality. RESULTS: The median duration of follow-up was 9.9 years (range, 132 days to 17 years). EIVA prevalence was 43.1% (95% CI: 34.5-51.7). Thirty-three cardiovascular deaths (25.4%) occurred. The hazard ratio of EIVA for cardiovascular death, after adjustment for age, was 1.84 (P = 0.09). An interaction was found between EIVA and cardiomegaly on x-ray. In the group with cardiomegaly, the hazard of dying was four times greater in the presence of EIVA (P for interaction = 0.05). CONCLUSION: In clinically stable chagasic subjects with cardiomegaly, EIVA is a clinically significant marker of total cardiovascular mortality and may be a useful risk stratification tool in this population.

Pericardium closure after heart operations: a safety option?

OBJECTIVES: Primary pericardium closure may reduce the risk of cardiac injury during chest re opening, especially the right ventricle, aorta and coronary bypass grafts. Nevertheless, concern about adverse hemodynamic effects prevents most heart surgeons of closuring the pericardium. METHODS: We evaluated 48 patients undergoing open heart surgery consecutively which the pericardium was closed in 30 patients (group A) and 18 patients, as a control group (group B) in which the pericardium was left open. All patients underwent posteroanterior and lateral chest roentgenograms before surgery and one week postoperatively. Postoperative evaluation also included echocardiograms, ECG and postoperative enzyme analysis. RESULTS: There were no deaths or any complications in both groups (acute myocardial infarction, stroke, bleeding or cardiac tamponate). It was observed statistically differences between both groups especially in echocardiogram parameters and cardiothoracic ratio without clinical impact. CONCLUSION: Pericardium closure is a simple method to facilitate resternotomy during subsequent re operative procedures. However, cardiac surgeons should be aware of the transient deterioration in hemodynamics associated with it, even thought there was no clinical significance in this study.

Fechamento primário do pericárdio em cirurgia cardíaca: uma opção segura? / Pericardium closure after heart operations: a safety option?

OBJETIVO: O fechamento primário do pericárdio pode reduzir o índice de lesão cardíaca durante as reoperações, principalmente do ventrículo direito, vasos da base e enxertos coronarianos. No entanto, a preocupação com as repercussões hemodinâmicas tem evitado a utilização da técnica por grande parte dos cirurgiões. MÉTODOS: Foram estudados trinta pacientes operados consecutivamente que tiveram o pericárdio fechado primariamente, denominados Grupo A. O grupo controle, Grupo B, sem o fechamento do pericárdio, foi constituído de outros 18 pacientes. Foram avaliados: telerradiografia de tórax, eletrocardiograma, ecocardiograma e dosagem de enzimas cardíacas (somente no caso de revascularização do miocárdio), todos os exames, tanto pré quanto pós-operatórios. RESULTADOS: Os pacientes operados, apesar de considerados de baixo risco cirúrgico, não apresentaram complicações (infarto agudo do miocárdio, AVC, sangramento ou tamponamento cardíaco). Foram observadas diferenças estatisticamente significativas entre os grupos, principalmente nos parâmetros do ecocardiograma e no índice cardiotorácico, sem repercussão clínica. CONCLUSÃO: O fechamento primário do pericárdio mostrou-se uma técnica simples para facilitar e reentrada no mediastino em uma reoperação. Contudo, é necessário observar as possíveis alterações hemodinâmicas inerentes ao método, embora nesta série não tenha apresentado repercussão clínica.

OBJECTIVES: Primary pericardium closure may reduce the risk of cardiac injury during chest re opening, especially the right ventricle, aorta and coronary bypass grafts. Nevertheless, concern about adverse hemodynamic effects prevents most heart surgeons of closuring the pericardium. METHODS: We evaluated 48 patients undergoing open heart surgery consecutively which the pericardium was closed in 30 patients (group A) and 18 patients, as a control group (group B) in which the pericardium was left open. All patients underwent posteroanterior and lateral chest roentgenograms before surgery and one week postoperatively. Postoperative evaluation also included echocardiograms, ECG and postoperative enzyme analysis. RESULTS: There were no deaths or any complications in both groups (acute myocardial infarction, stroke, bleeding or cardiac tamponate). It was observed statistically differences between both groups especially in echocardiogram parameters and cardiothoracic ratio without clinical impact. CONCLUSION: Pericardium closure is a simple method to facilitate resternotomy during subsequent re operative procedures. However, cardiac surgeons should be aware of the transient deterioration in hemodynamics associated with it, even thought there was no clinical significance in this study.

HIV prevalence among female sex workers, drug users and men who have sex with men in Brazil: a systematic review and meta-analysis.

BACKGROUND: The Brazilian response towards AIDS epidemic is well known, but the absence of a systematic review of vulnerable populations horizontal line men who have sex with men (MSM), female sex workers (FSW), and drug users (DU) remains a main gap in the available literature. Our goal was to conduct a systematic review and meta-analysis of studies assessing HIV prevalence among MSM, FSW and DU, calculating a combined pooled prevalence and summarizing factors associated the pooled prevalence for each group. METHODS: Nine electronic databases (MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE, AMED, CINAHL, TOXNET, SciELO, and ISI-Web of Science) were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1999 to 2009. To be included in the review, studies had to measure HIV prevalence and/or incidence as the primary outcome among at least one specific population under analysis. RESULTS: The studies targeting the three populations analyzed mostly young participants aged 30 years or less. Among FSW, eight studies were selected (3,625 participants), consistently identifying higher condom use with sexual clients than with occasional and stable partners. The combined HIV prevalence for FSW was 6.2 (95% CI: 4.4-8.3). Ten studies targeting MSM were identified (6,475 participants). Unprotected anal intercourse was commonly reported on those studies, but with great variability according to the nature of the relationship - stable vs. occasional sex partners--and sexual practice--receptive vs. insertive anal sex. Pooled HIV prevalence for MSM was 13.6 (95% CI: 8.2-20.2). Twenty nine studies targeting DU were identified (13,063 participants). Those studies consistently identified injection drug use and syringe/needle sharing as key predictors of HIV-infection, as well as engagement in sex work and male-to-male sex. The combined HIV prevalence across studies targeting DU was 23.1 (95% CI: 16.7-30.2). CONCLUSIONS: FSW, MSM and DU from Brazil have a much risk of acquiring HIV infection compared to the general population, among which HIV prevalence has been relatively low (~0.6%). Those vulnerable populations should be targeted by focused prevention strategies that provide accurate information, counseling and testing, as well as concrete means to foster behavior change (e.g. access to condoms, drug abuse treatment, and clean syringes in the case of active injecting drug users), tailored to gender and culture-specific needs. Programs that provide these services need to be implemented on public health services throughout the country, in order to decrease the vulnerability of those populations to HIV infection.

Adherence to antiretroviral therapy among HIV-infected drug users: a meta-analysis.

We conducted a meta-analysis of studies assessing adherence to highly active antiretroviral therapy (HAART) and a qualitative systematic review of factors associated with better HAART outcomes among HIV+ drug users (DU). Thirty-eight studies were considered, which analyzed 14,960 patients (11,394 HIV+ DU, 76.2%). Overall adherence (pooled percent of DU classified as adherent in each study) was 0.60 (95% CI: 0.52-0.68), similar to levels identified by studies conducted with HIV+ patients who are not drug users. Time frame used to measure adherence was an independent predictor of inter-study heterogeneity. The systematic review identified better HAART outcomes among former DU, those with less severe psychiatric conditions, those receiving opioid substitution therapy and/or psychosocial support. Patients initiating HAART with lower viral load and higher CD4 counts, and those without co-infections also had better treatment outcomes. Our findings suggest that HIV+ DU tend to be inappropriately assumed to be less adherent and unlikely to achieve desirable treatment outcomes, when compared to their non-DU cohort.

Adherence to antiretroviral therapy for human immunodeficiency virus/acquired immune deficiency syndrome among drug users: a systematic review.

AIMS: Adherence to highly active antiretroviral therapy (HAART) is a key predictor of survival for human immunodeficiency virus (HIV)-infected people. Suboptimal adherence among marginalized populations such as HIV-positive drug users could be associated with clinical failure and the emergence of viral resistance. OBJECTIVE: To conduct a systematic review of studies assessing adherence to HAART among HIV-positive drug users (DU) and identify factors associated with non-adherence to HIV treatment. DATA SOURCES: Seven electronic databases were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1996 to 2007. STUDY SELECTION AND DATA ABSTRACTION: Studies were excluded if they presented only qualitative data, were reviews themselves or assessed other populations without disaggregating data on DU. Findings on adherence were extracted and summarized. DATA SYNTHESIS: Forty-one studies were considered, which studied a total of 15 194 patients, the majority of whom were HIV-positive DU (n = 11 628, 76.5%). Twenty-two studies assessed adherence using patient self-reports, eight used pharmacy records, three used electronic monitoring [i.e. Medication Event Monitoring Systems (MEMS) caps], six studies used a combination of patient self-report, clinical data and MEMS-caps, and two analyzed secondary data. Overall, active substance use was associated with poor adherence, as well as depression and low social support. Higher adherence was found in patents receiving care in structured settings (e.g. directly observed therapy) and/or drug addiction treatment (especially substitution therapy). CONCLUSION: While lower than other populations-especially among users of stimulants, incarcerated DU and patients with psychiatric comorbidities-adherence to HAART among HIV-positive DU can be achieved. Better adherence was identified among those engaged in comprehensive services providing HIV and addiction treatment with psychosocial support.

Prevalence of human immunodeficiency virus drug resistance mutations and subtypes in drug-naive, infected individuals in the army health service of Rio de Janeiro, Brazil.

The prevalence of mutations that confer resistance to antiretroviral drugs was examined in 56 drug-naive, human immunodeficiency virus type 1 (HIV-1)-infected individuals from the Army Health Service in Rio de Janeiro, Brazil. No primary protease inhibitor mutations were found, but secondary mutations were observed in 51.2% of the samples. Fourteen percent of the viruses had reverse transcriptase inhibitor-associated mutations. Comparative analysis of protease secondary mutations from four different time periods in drug-naive patients in the city of Rio de Janeiro has indicated constant rates for particular mutations. Changes in CD4 cell counts and HIV viral load over time in subtype B- and non-B-infected drug-naive patients were not significantly different.

A lógica da determinaçäo do tamanho da amostra em investigaçöes epidemiológicas / The logic of sample size determination in epidemiological research

Uma das perguntas mais frequentes por parte dos pesquisadores da área da Saúde seja para um estudo em laboratório, clínico ou epidemiológico, se refere ao número de elementos que deve ser investigado a fim de se ter um estudo "confiável" ou "significativo". Ou seja, deseja-se saber qual o tamanho da amostra. Basicamente, o tamanho da amostra depende da precisäo desejada, de arbítrio do pesquisador. Entender a lógica por trás da sua determinaçäo é fundamental para o planejamento e suporte às conclusöes de qualquer investigaçäo epidemiológica. Este artigo procura explorar as idéias e os elementos influentes na determinaçäo do tamanho da amostra