Biblioteca Digital

The objectives of this study were to identify individuals with symptomatic and/or asymptomatic infection due to Leishmania (L.) infantum chagasi; to study the two types of infection, both clinically and immunologically, and to determine the prevalence rate of infection at the beginning of the study. This was a cross-sectional study with a cohort of 946 individuals, of both genders, from the age of 1 year, living in the municipality of Barcarena, PA, Brazil, an area endemic for American visceral leishmaniasis (AVL). The leishmanin skin test (LST) and the indirect fluorescent test (IFAT), were used for the diagnosis of infection. One hundred and twenty cases of infection were diagnosed, with a prevalence rate of 12.6%; eight cases showed high seroreactivity (1280-10240, IgG) in IFAT and no LST reaction; four of these cases were typical AVL and four had subclinical oligosymptomatic infection. Using two immunological methods with a clinical examination of the infected individuals enabled the identification of five clinical-immunological profiles which may promote a better understanding of the interaction between L. (L.) i. chagasi and the human immune response: asymptomatic infection (AI) 73.4%; subclinical resistant infection (SRI) 15%; subclinicat oligosymptomatic infection (SOI) 3%; symptomatic infection (AVL) 3% and indeterminate initial infection (III) 5%. (C) 2009 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.; Instituto Evandro Chagas (Secretaria de Vigilancia em Saude...

Introdução: Neutropenia febril é uma emergência médica que demanda um diagnóstico precoce e administração de antibióticos o mais breve possível. A procalcitonina (PCT) é um marcador inflamatório que vem sendo utilizado como um indicador de infecção bacteriana grave. A detecção precoce do quadro séptico é difícil, principalmente numa população heterogênea como no caso dos neutropênicos febris. A possibilidade de um único exame laboratorial poder identificar precocemente os quadros de sepse contribuiria de forma significativa para melhorar o prognóstico destes pacientes. Objetivo: Avaliar os níveis de PCT como marcador de infecção sistêmica comparados aos níveis de proteína C-reativa (PCR) em pacientes neutropênicos febris. Métodos: Foram estudadas amostras de 65 pacientes com a finalidade de determinar as concentrações séricas de PCT, PCR e outros parâmetros hematológicos em três momentos diferentes: antes da febre, no momento da febre e 72 após o término da febre. Os pacientes foram divididos inicialmente em quatro grupos: com infecção sistêmica comprovada laboratorial ou clinicamente (I), com febre de origem indeterminada - FOI- (II), com infecção localizada (III) e com infecção fúngica confirmada (IV). Posteriormente...

A dinâmica da leishmaniose visceral humana na Amazônia brasileira é pouco conhecida e nos últimos anos tem aumentado a incidência da doença principalmente no Estado do Pará. Os objetivos do estudo foram: I) identificar indivíduos com infecção sintomática e/ou assintomática por Leishmania (L.) infantum chagasi, II) estudar os dois tipos de infecção, tanto clínica quanto imunologicamente, e III) estudar a taxa de prevalência da infecção. O estudo foi de corte transversal com 946 indivíduos de ambos os sexos, com idade a partir de 1 ano, vivendo em área endêmica de leishmaniose visceral americana (LVA), município de Barcarena, Pará, Brasil. Para o diagnóstico da infecção, foram usadas a reação dérmica de hipersensibilidade retardada (Reação Intradérmica de Montenegro) - RIM e a Reação de Imunofluorêscencia Indireta (RIFI). Foram diagnosticados 120 casos de infecção com taxa de prevalência de 12.6%; 8 casos mostraram alta soro-reatividade (1.280 a 120.240) IgG utilizando-se o teste da RIFI e nenhuma reação na RIM; 4 casos foram típicos de LVA e outros 4 casos de infecção subclínica oligossintomática. Os dois métodos imunológicos usados simultaneamente com o exame clínico permitiram a identificação de 5 perfis clínico-imunológicos: Infecção Assintomática (IA) 73...

Introdução: o cateter central de inserção periférica (CCIP) tornou-se amplamente utilizado nas unidades de terapia intensiva neonatal (UTIN) na última década em razão da facilidade de sua instalação, permitindo a infusão de soluções endovenosas vesicantes, irritantes, hiperosmolares e de longa duração em veias centrais. Uma das complicações mais temidas relacionadas ao uso do CCIP é infecção de corrente sanguínea associada ao cateter cujo diagnóstico se confirma somente após a sua remoção, com o resultado de cultura da ponta do dispositivo e o resultado de hemocultura periférica do neonato. Objetivo: determinar a incidência de remoção por suspeita de infecção de corrente sanguínea relacionada ao CCIP e identificar os seus fatores de risco. Metodologia: coorte prospectiva composta por neonatos com CCIP internados em uma Unidade de Terapia Intensiva Neonatal de um hospital privado da cidade de São Paulo no período de 31 de agosto de 2010 a 30 de agosto de 2012. As variáveis de exposição analisadas foram às relacionadas às características demográficas e clinicas dos neonatos, procedimentos relacionados à inserção do cateter, tipo de terapia intravenosa infundida pelo CCIP e o tempo de permanência do cateter. O desfecho analisado foi o motivo de remoção do cateter - eletivo ou por suspeita de infecção. Os dados obtidos de registros de prontuário foram armazenados em planilha Microsoft Excel 2010® e analisados com o software Stata 11...

O Citomegalovírus Humano (HCMV) é o principal causador de complicações pós-transplante. Métodos específicos que permitam identificar, precocemente, os pacientes com risco de desenvolvimento de doença, para os quais tratamento é indicado, têm sido requeridos, a fim de que poucos pacientes sejam desnecessariamente tratados e para a efetiva instituição terapêutica. A "Nested-PCR", dupla Reação em Cadeia da Polimerase, é um teste comumente utilizado no diagnóstico da infecção ativa por HCMV, contudo, quando realizada em leucócitos do sangue periférico, devido à sua alta sensibilidade, não apresenta boa correlação com o desenvolvimento de doença por HCMV. A detecção do DNA do HCMV no soro, pela PCR, tem sido associada com o desenvolvimento de doença por HCMV. Neste estudo, nós aplicamos a "Nested-PCR" em leucócitos do sangue periférico (denominada "L-PCR"), o método Convencional do Laboratório, e em soro ("sPCR"), para o diagnóstico da infecção ativa por HCMV, a fim de estabelecermos a correlação dos resultados obtidos, de ambos os métodos, com o desenvolvimento de infecção sintomática. Com este propósito, nós avaliamos, prospectivamente, amostras de 37 pacientes, 20 submetidos a transplante renal...

CONTEXT: Healthcare-associated infection represents the most frequent adverse event during care delivery. Medical advances like percutaneous endoscopic gastrostomy have brought improvement on quality of life to patients but an increased risk of healthcare-associated infection. Predictive risk factors for peristomal wound infection are largely unknown but evidence suggests that antibiotic prophylaxis and preventive strategies related to infection control may reduce infection rates. OBJECTIVES: The primary aim was to evaluate the global prevalence rate of peristomal infection. Secondary objectives were to characterise the positive culture results, to evaluate the prophylactic antibiotic protocol and to identify potential risk factors for peristomal infection. METHODS: Retrospective study of 297 patients with percutaneous endoscopic gastrostomy performed at a general hospital between January 2004 and September 2010. Patients received prophylactic cefazolin before the endoscopic gastrostomy procedure. Medical records were reviewed for demographic data, underling disease conditions to percutaneous endoscopic gastrostomy and patient potential intrinsic risk factors. Statistical analysis was made with the statistical program SPSS 17.0. RESULTS: A total of 297 percutaneous endoscopic gastrostomy tubes were inserted. Wound infection occurred in 36 patients (12.1%). Staphylococcus aureus methicillin resistant was the most frequently isolated microorganism (33.3%) followed by Pseudomonas aeruginosa (30.6%). The incidence rate had been rising each year and differ from 4.65% in 2004/2007 to 17.9% in 2008/2010. This finding was consistent with the increasing of prevalence global infection rates of the hospital. Most of the infections (55.6%) were detected in the first 10 days post procedure. There was no significant difference in age...

BACKGROUND: There is a lack of consensus regarding the definition of risk factors for healthcare-associated infection (HCAI). The purpose of this study was to identify additional risk factors for HCAI, which are not included in the current definition of HCAI, associated with infection by multidrug-resistant (MDR) pathogens, in all hospitalized infected patients from the community. METHODS: This 1-year prospective cohort study included all patients with infection admitted to a large, tertiary care, university hospital. Risk factors not included in the HCAI definition, and independently associated with MDR pathogen infection, namely MDR Gram-negative (MDR-GN) and ESKAPE microorganisms (vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species, carbapenem-hydrolyzing Klebsiella pneumonia and MDR Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species), were identified by logistic regression among patients admitted from the community (either with community-acquired or HCAI). RESULTS: There were 1035 patients with infection, 718 from the community. Of these, 439 (61%) had microbiologic documentation; 123 were MDR (28%). Among MDR: 104 (85%) had MDR-GN and 41 (33%) had an ESKAPE infection. Independent risk factors associated with MDR and MDR-GN infection were: age (adjusted odds ratio (OR) = 1.7 and 1.5...

"Context - Healthcare-associated infection represents the most frequent adverse event during care delivery. Medical advances like percutaneous endoscopic gastrostomy have brought improvement on quality of life to patients but an increased risk of healthcare-associated infection. Predictive risk factors for peristomal wound infection are largely unknown but evidence suggests that antibiotic prophylaxis and preventive strategies related to infection control may reduce infection rates. Objectives - The primary aim was to evaluate the global prevalence rate of peristomal infection. Secondary objectives were to characterise the positive culture results, to evaluate the prophylactic antibiotic protocol and to identify potential risk factors for peristomal infection. Methods - Retrospective study of 297 patients with percutaneous endoscopic gastrostomy performed at a general hospital between January 2004 and September 2010. Patients received prophylactic cefazolin before the endoscopic gastrostomy procedure. Medical records were reviewed for demographic data, underling disease conditions to percutaneous endoscopic gastrostomy and patient potential intrinsic risk factors. Statistical analysis was made with the statistical program SPSS 17.0. Results - A total of 297 percutaneous endoscopic gastrostomy tubes were inserted. Wound infection occurred in 36 patients (12.1%). Staphylococcus aureus methicillin resistant was the most frequently isolated microorganism (33.3%) followed by Pseudomonas aeruginosa (30.6%). The incidence rate had been rising each year and differ from 4.65% in 2004/2007 to 17.9% in 2008/2010. This finding was consistent with the increasing of prevalence global infection rates of the hospital. Most of the infections (55.6%) were detected in the first 10 days post procedure. There was no significant difference in age...

CONTEXT: Healthcare-associated infection represents the most frequent adverse event during care delivery. Medical advances like percutaneous endoscopic gastrostomy have brought improvement on quality of life to patients but an increased risk of healthcare-associated infection. Predictive risk factors for peristomal wound infection are largely unknown but evidence suggests that antibiotic prophylaxis and preventive strategies related to infection control may reduce infection rates. OBJECTIVES: The primary aim was to evaluate the global prevalence rate of peristomal infection. Secondary objectives were to characterise the positive culture results, to evaluate the prophylactic antibiotic protocol and to identify potential risk factors for peristomal infection. METHODS: Retrospective study of 297 patients with percutaneous endoscopic gastrostomy performed at a general hospital between January 2004 and September 2010. Patients received prophylactic cefazolin before the endoscopic gastrostomy procedure. Medical records were reviewed for demographic data, underling disease conditions to percutaneous endoscopic gastrostomy and patient potential intrinsic risk factors. Statistical analysis was made with the statistical program SPSS 17.0. RESULTS: A total of 297 percutaneous endoscopic gastrostomy tubes were inserted. Wound infection occurred in 36 patients (12.1%). Staphylococcus aureus methicillin resistant was the most frequently isolated microorganism (33.3%) followed by Pseudomonas aeruginosa (30.6%). The incidence rate had been rising each year and differ from 4.65% in 2004/2007 to 17.9% in 2008/2010. This finding was consistent with the increasing of prevalence global infection rates of the hospital. Most of the infections (55.6%) were detected in the first 10 days post procedure. There was no significant difference in age...

OBJECTIVE: To determine the prevalence rates of infections among intensive care unit patients, the predominant infecting organisms, and their resistance patterns. To identify the related factors for intensive care unit-acquired infection and mortality rates. DESIGN: A 1-day point-prevalence study. SETTING:A total of 19 intensive care units at the Hospital das Clínicas - University of São Paulo, School of Medicine (HC-FMUSP), a teaching and tertiary hospital, were eligible to participate in the study. PATIENTS: All patients over 16 years old occupying an intensive care unit bed over a 24-hour period. The 19 intensive care unit s provided 126 patient case reports. MAIN OUTCOME MEASURES: Rates of infection, antimicrobial use, microbiological isolates resistance patterns, potential related factors for intensive care unit-acquired infection, and death rates. RESULTS: A total of 126 patients were studied. Eighty-seven patients (69%) received antimicrobials on the day of study, 72 (57%) for treatment, and 15 (12%) for prophylaxis. Community-acquired infection occurred in 15 patients (20.8%), non- intensive care unit nosocomial infection in 24 (33.3%), and intensive care unit-acquired infection in 22 patients (30.6%). Eleven patients (15.3%) had no defined type. The most frequently reported infections were respiratory (58.5%). The most frequently isolated bacteria were Enterobacteriaceae (33.8%)...

CONTEXT AND OBJECTIVE: Hematopoietic stem cell transplantation (HSCT) has been widely used for treating oncological and hematological diseases. Although HSCT has helped to improve patient survival, the risk of developing infection during hospitalization is an important cause of morbidity and mortality. This study aimed to analyze the infection profile during hospitalization and the associated risk factors among patients undergoing autologous HSCT at the University Hospital, Universidade Federal de Juiz de Fora. DESIGN AND SETTING: This was a cross-sectional study on patients undergoing autologous HSCT at a public university hospital. METHODS: Patients with febrile neutropenia between 2004 and 2009 were retrospectively evaluated regarding their infection profile and associated risk factors. RESULTS: Infection occurred in 57.2% of 112 patients with febrile neutropenia. The main source of infection was the central venous catheter (25.9%). Infection was chiefly due to Gram-positive bacteria, although Gram-negative-related infections were more severe and caused a higher death rate. Sex, age, skin color, nutritional status and underlying disease were not associated with the development of infection. Patients with severe mucositis (Grades III and IV) had a higher infection rate (P < 0.001). Patients who developed pulmonary complications during hospitalization had higher infection rates (P = 0.002). Infection was the main cause of death (57.1%) in the study sample. CONCLUSION: Strategies aimed at reducing infection-related mortality rates among patients undergoing autologous HSCT are necessary.

Dendritic cells (DC) are believed to play an important role in the initiation of innate and adaptive immune responses to infection, including respiratory tract infections, where respiratory DC (RDC) perform this role. In this report, we examined the susceptibilities of isolated murine RDC to influenza virus infection in vitro and the effect of the multiplicity of infection (MOI) on costimulatory ligand upregulation and inflammatory cytokine/chemokine production after infection. We found that the efficiency of influenza virus infection of RDC increased with increasing MOIs. Furthermore, distinct subpopulations of RDC differed in their susceptibilities to influenza virus infection and in the magnitude/tempo of costimulatory ligand expression. Additional characterization of the CD11c-positive (CD11c+) RDC revealed that the identifiable subsets of RDC differed in susceptibility to infection, with CD11c+ CD103+ DC exhibiting the greatest susceptibility, CD11c+ CD11bhi DC exhibiting intermediate susceptibility, and CD11c+ B220+ plasmacytoid DC (pDC) exhibiting the least susceptibility to infection. A companion analysis of the in vivo susceptibilities of these RDC subsets to influenza virus revealed a corresponding infection pattern. The three RDC subsets displayed different patterns of cytokine/chemokine production in response to influenza virus infection in vitro: pDC were the predominant producers of most cytokines examined...

The initial interaction between HIV-1 and the host occurs at the mucosa during sexual intercourse. In cervical mucosa, HIV-1 exists both as free and opsonized virions and this might influence initial infection. We used cervical explants to study HIV-1 transmission, the effects of opsonization on infectivity, and how infection can be prevented. Complement opsonization enhanced HIV-1 infection of dendritic cells (DCs) compared with that by free HIV-1, but this increased infection was not observed with CD4+ T cells. Blockage of the α4-, β7-, and β1-integrins significantly inhibited HIV-1 infection of both DCs and CD4+ T cells. We found a greater impairment of HIV-1 infection in DCs for complement-opsonized virions compared with that of free virions when αM/β2- and α4-integrins were blocked. Blocking the C-type lectin receptor macrophage mannose receptor (MMR) inhibited infection of emigrating DCs but had no effect on CD4+ T-cell infection. We show that blocking of integrins decreases the HIV-1 infection of both mucosal DCs and CD4+ T cells emigrating from the cervical tissues. These findings may provide the basis of novel microbicidal strategies that may help limit or prevent initial infection of the cervical mucosa, thereby reducing or averting systemic HIV-1 infection.

Cytomegalovirus (CMV) infection is a common infection in adults (seropositive 60–99% globally), and is associated with cardiovascular diseases, in line with risk factors such as hypertension and atherosclerosis. Several viral infections are linked to hypertension, including human herpes virus 8 (HHV-8) and HIV-1. The mechanisms of how viral infection contributes to hypertension or increased blood pressure are not defined. In this report, the role of CMV infection as a cause of increased blood pressure and in forming aortic atherosclerotic plaques is examined. Using in vivo mouse model and in vitro molecular biology analyses, we find that CMV infection alone caused a significant increase in arterial blood pressure (ABp) (p<0.01 (sim)0.05), measured by microtip catheter technique. This increase in blood pressure by mouse CMV (MCMV) was independent of atherosclerotic plaque formation in the aorta, defined by histological analyses. MCMV DNA was detected in blood vessel samples of viral infected mice but not in the control mice by nested PCR assay. MCMV significantly increased expression of pro-inflammatory cytokines IL-6, TNF-(alpha), and MCP-1 in mouse serum by enzyme-linked immunosorbent assay (ELISA). Using quantitative real time reverse transcriptase PCR (Q-RT-PCR) and Western blot...

Background: There is an extensive critical care literature for central venous catheter and arterial line infection, duration of catheterization, and compliance with infection control procedures. The emergency medicine literature, however, contains very little data on central venous catheters and arterial lines. As emergency medicine practice continues to incorporate greater numbers of critical care procedures such as central venous catheter placement, infection control is becoming a greater issue. Aims: We performed a systematic review of studies reporting baseline data of ED-placed central venous catheters and arterial lines using multiple search methods. Methods: Two reviewers independently assessed included studies using explicit criteria, including the use of EDplaced invasive lines, the presence of central line-associated bloodstream infection, and excluded case reports and review articles. Finding significant heterogeneity among studies, we performed a qualitative assessment. Results: Our search produced 504 abstracts, of which 15 studies were evaluated, and 4 studies were excluded because of quality issues leaving 11 cohort studies. Four studies calculated infection rates, ranging 0–24.1/1,000 catheter-days for central line-associated and 0–32.8/1...

Background: Although neonatal infections cause a significant proportion of deaths in the first week of life, little is known about the burden of neonatal disease originating from maternal infection or colonization globally. This paper describes the prevalence of vertical transmission – the percentage of newborns with neonatal infection among newborns exposed to maternal infection. Methods: We searched Pubmed, Embase, Scopus, Web of Science, Cochrane Library, and WHO Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection. Studies that measured prevalence of bacterial vertical transmission were included. Random effects meta-analyses were used to pool data to calculate prevalence estimates of vertical transmission. Results: 122 studies met the inclusion criteria. Only seven studies (5.7%) were from very high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of infection (lab-confirmed, clinical signs), colonization, and risk factors of infection. The prevalence of early onset neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 17.2% (95%CI 6.5-27.9). The prevalence of neonatal lab-confirmed infection among newborns of colonized mothers was 0% (95% CI 0.0-0.0). The prevalence of neonatal surface colonization among newborns of colonized mothers ranged from 30.9-45.5% depending on the organism. The prevalence of neonatal lab-confirmed infection among newborns of mothers with risk factors (premature rupture of membranes...

Since the Morris worm was released in 1988, Internet worms continue to be one of top security threats. For example, the Conficker worm infected 9 to 15 million machines in early 2009 and shut down the service of some critical government and medical networks. Moreover, it constructed a massive peer-to-peer (P2P) botnet. Botnets are zombie networks controlled by attackers setting out coordinated attacks. In recent years, botnets have become the number one threat to the Internet. The objective of this research is to characterize spatial-temporal infection structures of Internet worms, and apply the observations to study P2P-based botnets formed by worm infection. First, we infer temporal characteristics of the Internet worm infection structure, i.e., the host infection time and the worm infection sequence, and thus pinpoint patient zero or initially infected hosts. Specifically, we apply statistical estimation techniques on Darknet observations. We show analytically and empirically that our proposed estimators can significantly improve the inference accuracy. Second, we reveal two key spatial characteristics of the Internet worm infection structure, i.e., the number of children and the generation of the underlying tree topology formed by worm infection. Specifically...

The human hepatitis B virus (HBV) is the prototype member of the Hepadnaviridae family of viruses. Various other hepadnaviruses are used as models to study human HBV infections as all Hepadnaviridae family members have similar virus structure and replication strategies. The studies performed and described in this thesis were carried out using duck hepatitis B virus (DHBV) infection of Pekin ducks as a model system. Hepadnavirus infections can have either an acute or a chronic outcome. The factors that contribute to these outcomes include the immune response, the age of the host at the time of infection as well as size of viral inoculum. The overall aim of this project was to gain a detailed understanding of the mechanisms involved in clearance of virus and resolution of acute DHBV infections. As a first step, molecular and immunohistochemical detection methods for a range of cellular markers in ducks had to be developed as assays were not readily available. Quantitative reverse transcription PCR assays (qRT-PCR) were developed for the detection of mRNA of the duck T-lymphocyte markers, CD3, CD4, CD8, duck cytokines, IFN-α, IFN-γ, TNF-α and the duck housekeeping genes, β-actin and GAPDH. Immunohistochemistry was developed for the detection of duck CD4 + and CD8 + on T cells and for the detection of proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation. These methods were then widely used throughout the project. The innate immune response during HBV infections is not well understood. Toll-like receptors (TLR) are a family of pattern recognition receptors that form part of the innate immune response and are involved in the recognition of bacterial...

Introdução: A infecção representa importante causa de morbidade e mortalidade materna, sendo uma preocupação crescente no mundo todo. As doenças respiratórias, especialmente as virais, têm se destacado justamente pelo potencial de epidemia com que ameaçam a saúde da população mundial e pela vulnerabilidade identificada durante a gestação. Objetivo: Avaliar o impacto da morbidade materna grave (MMG) atribuível à infecção (sepse, meningite e doença respiratória) e os fatores associados ao pior resultado materno (near miss e óbito), entre mulheres da Rede Brasileira de Vigilância da Morbidade Materna Grave. Métodos: análise secundária de um estudo transversal, multicêntrico, que incluiu 27 centros de referência obstétrica das cinco regiões do Brasil no período de 2009 e 2010. A vigilância prospectiva dos casos de infecção grave foi realizada utilizando os critérios da OMS de condições potencialmente ameaçadoras da vida (CPAV) e near miss materno (NMM). Os principais focos de infecção foram identificados e comparados a outras causas de MMG. Mulheres com complicação devido à doença respiratória também foram avaliadas em dois grupos: com e sem suspeita de A(H1N1)pdm09 e também comparadas a outras causas de MMG. Casos com suspeita de A(H1N1)pdm09 foram revisados e separados em três grupos: não-testados...