A problemática da infecção pelo citomegalovírus em pacientes imunodeprimidos

Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM) DCMUNIFESP, EPM, DCMSciEL

Vírus causadores de câncer e o papel da medicina laboratorial: revisão de literatura e perspectivas

Cancer-causing viruses are responsible for up to 20% of cancers with infectious etiology, representing a serious public health problem worldwide. Since the discovery of the first human cancer-causing virus, several others have been associated with neoplasias. Recent advances in technologies for the determination of genomic and proteomic profiles have resulted in the discovery and availability of tumor markers with potential application in the screening, diagnosis, prognosis and treatment of cancer. Therefore, laboratory medicine has stood out as a fundamental tool in the prevention and management of these diseases.Os vírus causadores de câncer são responsáveis por até 20% dos cânceres de etiologia infecciosa, representando um grave problema de saúde pública em todo o mundo. Desde a descoberta do primeiro vírus causador de neoplasias em humanos, vários outros têm sido associados ao câncer. Recentes avanços nas tecnologias de determinação de perfis genômicos e proteômicos resultaram na descoberta e na disponibilização de marcadores tumorais com potencial aplicação no rastreamento, no diagnóstico, no prognóstico e no tratamento do câncer, destacando a medicina laboratorial como ferramenta fundamental na prevenção e no manejo dessas enfermidades.Universidade Federal de São Paulo (UNIFESP)UNIFESPSciEL

Hepatitis C and hemodialysis: a review

Hepatitis C is a serious public health problem throughout the world; chronic renal patients are highly exposed to this infection. This could be due to a failure to identify carriers of this disease or because of a lack of truly effective biosafety measures implemented in the dialysis units. Molecular biology techniques have allowed for the understanding of this virus in detail, including its replication mechanisms. Epidemiological studies have been made throughout the world, with the goal of determining the dissemination dynamics of this agent, in addition to examining the predominance of the different genotypes, and the possible mutants that are involved. Many questions must still be answered concerning infection by Hepatitis C virus (HCV); this is especially important for immunosuppressed patients.Adolfo Lutz Institute Virology Service Laboratory of HepatitisIrmandade da Santa Casa de Misericórdia de São PauloFaculty of Medical Sciences Santa Casa de São Paulo Molecular Medicine LaboratoryFederal University of São Paulo Medical School Department of Infectious and Parasitic InfectionsUNIFESP, Medical School Department of Infectious and Parasitic InfectionsSciEL

A simple and cheaper in house varicella zoster virus antibody indirect ELISA

We have developed a cheaper an simple in house indirect ELISA that uses the live attenuated VZV vaccine as a coating antigen. The alternative ELISA had an agreement of 94% when compared with a commercial VZV ELISA kit. Moreover, our ELISA proved to be more reliable than the kit when assessing true negative samples. By adding a standard serum, we were able to produce results in international units per millilitre. Also, the addition of an extra step with 8M urea allowed the assessment of VZV IgG avidity without excessive costs. The cost per sample to test VZV IgG was 2.7 times cheaper with our ELISA, allowing the testing of many samples without the burden of production of VZV antigen in the laboratory.Desenvolvemos um ensaio imunoenzimático (ELISA) indireto simples e econômico para detecção de anticorpos contra o vírus da varicela zoster (VVZ) que utiliza a vacina contendo o vírus vivo atenuado como antígeno para recobrir a placa. Este ELISA mostrou uma concordância de 94% quando comparado com um kit de ELISA comercial para anticorpos contra varicela. Além disso, nosso ELISA mostrou ser mais confiável que o kit quando amostras comprovadamente negativas foram testadas. O uso de um soro padrão de referência, calibrado em unidades internacionais por mililitro, possibilitou também que os resultados pudessem ser comparados com outros estudos. O acréscimo de uma etapa extra com solução de uréia 8M permitiu avaliação de avidez de IgG para VVZ sem custos excessivos. O custo por amostra para testar IgG contra VVZ com nosso ELISA foi 2,7 vezes mais barato quando comparado com o kit comercial

Development of a prototype immunochromatographic test for rapid diagnosis of respiratory adenovirus infection

Human adenoviruses comprise an important group of etiologie agents that are responsible for various diseases in adults and children, such as respiratory, ocular, gastroenteric, and urinary infections. In immunocompromised and organ-transplanted individuals, these agents can cause generalized infections. Rapid diagnostic methods for detecting these infectious agents are not widely available.& para;& para;The aim of this work was to produce monoclonal and polyclonal anti-adenovirus antibodies to be used in a rapid diagnostic test for respiratory infections.& para;& para;Adenovirus hexons were satisfactorily purified by ultracentrifugation and chromatography. After virus purification, anti-hexon monoclonal antibodies were produced and characterized, following classical methods. Antibodies were specific for adenoviruses 2,3,5, and 41. The proposed immunochromatographic test was standardized using colloidal gold.& para;& para;The standardization of the rapid test was sufficient to detect adenovirus antigens (in nasopharyngeal lavage samples) with sensitivity of 100% and specificity of 85% when compared to direct immunofluorescence.& para;& para;The immunochromatographic assay prototype was sufficiently sensitive to detect B (3), C (2 and 5), and F (41) adenovirus samples. Although based on preliminary data, the test demonstrated the same performance as direct immunofluorescence, but with the advantage of being a point-of-care test. Further studies are still needed to confirm its effectiveness in clinical practice. (C) 2017 Sociedade Brasueira de Infectologia. Published by Elsevier Editera Ltda.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Fed São Paulo, Dept Med, Lab Virol, Disciplina Infectol, São Paulo, SP, BrazilUniv Fed São Paulo, Inst Biociencias, Dept Microbiol, Lab Adenovirus, São Paulo, SP, BrazilInst Biociencias, Dept Microbiol, Lab Micol, São Paulo, SP, BrazilInst Butantan, Lab Bacteriol, São Paulo, SP, BrazilUniv Fed São Paulo, Dept Med, Lab Virol, Disciplina Infectol, São Paulo, SP, BrazilUniv Fed São Paulo, Inst Biociencias, Dept Microbiol, Lab Adenovirus, São Paulo, SP, BrazilFAPESP: 2011/50100-6Web of Scienc

Risk factors for poor immune response to influenza vaccination in elderly people

Influenza vaccination of elderly people is efficacious and cost effective for the prevention of influenza and its complications. Some studies have pointed out low immunogenicity in this group. Health status has been poorly investigated as a risk factor that may influence the immune response to influenza vaccine. We established an immunization response study of a highly-matched elderly population in a nursing home. One-hundred-twenty subjects of Ashkenazian origin had their vaccine-induced antibody response assessed. Good response was obtained in 30.8% (37/120), and 31.7% (38/120) did not react. A lack of good response was found to be associated with dementia (P=0.016) in a multivariate analysis. In addition to dementia, malnutrition was frequently observed among poor responders, suggesting that these factors should be considered in vaccination studies. Chemoprophylaxis in addition to vaccination for elderly presenting dementia should be considered, particularly for those people living nursing homes.Federal University of São Paulo Department of Infectious Diseases Laboratory of Clinical VirologyFederal University of São Paulo Federal University of São PauloUNIFESP, Department of Infectious Diseases Laboratory of Clinical VirologyUNIFESP, UNIFESPSciEL

Infections with human coronaviruses NL63 and OC43 among hospitalised and outpatient individuals in São Paulo, Brazil

The incidence and clinical features of human coronaviruses (HCoVs) among Brazilian patients with respiratory illness are not well known. We investigated the prevalence of HCoVs among Brazilian outpatients and hospitalised patients with respiratory illnesses during 2009 and 2010. To identify the HCoVs, pancoronavirus and species-specific reverse-transcriptase polymerase chain reaction assays were performed. Five of 394 samples were positive for HCoVs (1.2%): 1/182 (0.5%) outpatients and 4/212 (1.8%) hospitalised patients. The OC43 and NL63 HCoVs were identified. Two patients were admitted to the intensive care unit. Underlying chronic disease was reported in cases and one diabetic adult died. HCoVs can cause lower respiratory infections and hospitalisation. Patients with pre-existing conditions and respiratory infections should be evaluated for HCoV infections.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Laboratório de Virologia ClínicaUNIFESP, Depto. de Medicina Laboratório de Virologia ClínicaSciEL

Rotavirus genotypes as etiological agents of diarrhoea in general populations of two geographic regions of Brazil

Rotavirus is the main global cause of severe childhood diarrhoea among children. In 2006, Rotarix® (G1P[8]) was introduced into Brazil’s National Immunization Program. The vaccine coverage rate was 84.4% in 2009. Evidences of increasing G2P[4] after 2006 opened up the discussion about the vaccine effectiveness to non-G1 strains. The aim of this study was to identify the circulating rotavirus genotypes in two Brazilian regions during 2009. A total of 223 positive samples by immunochromatography and latex agglutination assay from the Northeast (Bahia/Pernambuco States) and Southeast (São Paulo/Rio de Janeiro States) regions were included in the study. The samples were submitted to genotyping by nested-PCR according to VP7(G) and VP4(P) and 175 samples (78.5%) were able to be characterized. Considering the characterization of VP7, the G-types detected were G1, G2, and G4 in the Northeast, and G2, G3, G5, and G9 in the Southeast. Considering the characterization of VP4, the P-types detected were P[4], P[8], and P[6]/P[9] in the Northeast and the Southeast. The most frequent mixed types found were G2P[4]/G2P[NT](81.4%), G2P[6](5.2%), G1P[6](5.2%) in the Northeast, and G2P[4]/G2P[NT](78.8%), G2P[6](8.2%), G9P[8](4.7%) in the Southeast. Among immunized individuals whose age ranged from 0-4 years, the G2P[4]/G2P[NT] genotype was identified in 91,0% of cases, and among non-immunized individuals of the same age, the G2P[4]/G2P[NT] genotype was identified in 85.7% of the cases. In accordance with the high level of vaccine coverage, the data suggest that the circulation of G2P[4] in these regions had a considerable increase after the introduction of Rotarix®

Correlation between specific IgM levels and percentage IgG-class antibody avidity to Toxoplasma gondii

Toxoplasmosis is an usually asymptomatic worldwide disseminated infection. In its congenital presentation it may lead to abortion or fetal malformations. Antenatal evaluation is considered of paramount importance to identify seronegative women and allow for prophylaxis. Recent improvements in sensitivity of IgM tests has made IgM detection an extremely protracted acute phase marker, and IgG avidity evaluation test became necessary. Observation has shown that a correlation can be established between IgM levels and avidity percentages, suggesting that frequently the avidity test may not be necessary. In this study we analyzed Toxoplasma gondii IgM levels of 202 samples and their IgG avidity percentages, in order to define specific levels whose IgM quantification could by itself define serodiagnosis and therefore make the avidity evaluation unnecessary. We showed that for IgM levels bellow 2.0 and above 6.0 serodiagnosis of toxoplasmosis could be established without need of IgG avidity test. IgM levels between these two parameters are associated with varying avidity indexes highlighting the importance of its evaluation as a means to confirm toxoplasmosis. Following this demonstration it was possible to avoid the avidity test for 75% of the cases, to reduce the turnaround time and to reduce costs.A Toxoplasmose é uma infecção universal e usualmente assintomática. A forma congênita, entretanto, pode resultar em aborto ou mal formações. Testes sorológicos estão indicados em situações onde há suspeita clínica, e na triagem pré-natal, quando são extremamente importantes para rastrear a infecção e orientar a gestante. O aumento da sensibilidade das técnicas para detecção de IgM, tornou necessário o desenvolvimento de recursos, como a avidez de IgG, visando obter novo marcador de infecção aguda. Embora exista correlação entre níveis de IgM e grau de avidez de IgG, a maioria dos testes de avidez associa-se a níveis baixos de IgM, sugerindo que o teste de avidez não fosse necessário. Portanto, correlacionamos níveis de IgM de 202 amostras com seu respectivo nível de avidez de IgG, dirigidos contra o Toxoplasma, objetivando estabelecer valores claros para a sua indicação. Pôde-se observar que, para IgM ; 6,0, a definição sorológica pode ser feita independentemente da avidez. Níveis de IgM dentro desse intervalo associam-se a índices variados de avidez e, portanto, ressaltam a importância deste teste para definição sorológica do quadro. Com essa abordagem, foi possível diminuir a indicação do teste de avidez em 75%, reduzir o tempo para liberação dos resultados e o custo unitário do teste para IgM