Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2013-10-18T19:05:14Z No. of bitstreams: 1 Andréia Carvalho dos Santos. Diagnostico sorologico...2011.pdf: 1884519 bytes, checksum: 6aff70f55415c00ce177ca938c909c5e (MD5) / Made available in DSpace on 2013-10-18T19:05:14Z (GMT). No. of bitstreams: 1 Andréia Carvalho dos Santos. Diagnostico sorologico...2011.pdf: 1884519 bytes, checksum: 6aff70f55415c00ce177ca938c909c5e (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / A confirmação da leptospirose utilizando o Teste de Aglutinação Microscópica (MAT) requer amostras da fase aguda e convalescente para identificar soroconversão ou aumento de quatro vezes nos títulos. A Organização Mundial de Saúde (OMS) recomenda que a coleta da amostra convalescente seja realizada ≥14 dias após a coleta da amostra aguda. No entanto, a dificuldade na coleta de amostras convalescentes impede a confirmação dos casos e é uma das principais causas para sub-notificação da leptospirose. Este estudo investigou a viabilidade da coleta de uma amostra de soro aguda tardia de casos internados com leptospirose e avaliou se a análise sorológica desta amostra pode melhorar a eficiência do protocolo de confirmação diagnóstica de leptospirose. De 2003 a 2009, uma vigilância hospitalar ativa em Salvador-Brasil, identificou prospectivamente pacientes hospitalizados com suspeita clínica da leptospirose. Três amostras de sangue foram coletadas para cada caso: uma amostra aguda precoce, uma amostra aguda tardia e uma amostra convalescente, coletadas respectivamente nas primeiras 24 horas após hospitalização, e 4 e ≥14 dias depois da coleta da primeira amostra. Os pacientes identificados tiveram o diagnóstico de leptospirose confirmado por soroconversão, aumento de quatro vezes de títulos, ou título único ≥1:800 no MAT. O desempenho diagnóstico do MAT e do ELISA IgM na avaliação combinada das amostras aguda precoce e aguda tardia foi comparado ao desempenho da avaliação das amostras aguda precoce e convalescente que segue a recomendação de testagem da OMS. Nós confirmamos 643 (68%) dos 938 casos suspeitos. A coleta de amostra convalescente foi possível para 63% dos pacientes confirmados, e 55% dos pacientes suspeitos. Em contraste, a amostra da fase aguda tardia foi coletada para 77% e 66% dos pacientes confirmados e suspeitos, respectivamente. Para os 302 casos confirmados que tiveram as três amostras de soro coletadas, a sensibilidade do MAT e do IgM-ELISA na análise das amostras aguda precoce e tardia foi de 97% (IC95%, 94-99%) e 96% (93-98%), respectivamente, em comparação aos resultados da análise das amostras aguda precoce e convalescente. Em contraste, considerando apenas as amostras agudas destes 302 pacientes, a sensibilidade do MAT e do IgM-ELISA foi de 44% (38-50%) e 75% (69-79%), respectivamente. Amostra aguda tardia e convalescente foi obtida dos casos suspeitos de leptospirose que evoluíram para óbito de 32% e 6%, respectivamente. Os resultados indicam que a coleta e o teste sorológico da amostra aguda tardia de pacientes hospitalizados por leptospirose é viável e melhora a eficiência dos atuais protocolos de confirmação laboratorial de casos de leptospirose. / Confirmation of leptospirosis with MAT requires evaluating acute and convalescent-phase sera samples to identify seroconversion or fourfold rise in titers. Current World Health Organization (WHO) protocols recommend that convalescent samples are collected with ≥14days after the acute sample collection. However, the difficulty in collecting convalescent samples hampers case confirmation and is a major cause for leptospirosis under-reporting. This study evaluated feasibility of collecting a late acute-sera sample from hospitalized cases of leptospirosis and determined to serological analysis of this sample can improve the efficiency of the protocol to confirm the diagnosis of leptospirosis. From 2003 to 2009, active hospital-based surveillance in Salvador-Brazil prospectively identified hospitalized cases of patients with clinical suspicion of leptospirosis. Three blood samples were collected for each case: an early acute sample, a sample of late acute and convalescent sample collected during the first 24 hours after hospitalization 4 and ≥ 14 days after the first sampling, respectively. The identified patients were diagnosed with leptospirosis by seroconversion, fourfold rise in titers, or a titer ≥1:800 in the MAT. The diagnostic performance of the MAT and IgM ELISA in the combined sample of early acute and late acute sample performance was compared to the early assessment of acute and convalescent samples following a WHO recommendation for testing. We confirmed the leptospirosis diagnosis in 643 (68%) of 938 suspected cases. Convalescent-phase samples were collected from 63% of the confirmed patients, but in only 55% of the suspected cases. In contrast, the late acute phase sample was collected for 77% and 66% of confirmed and suspected patients, respectively. Among the 302 confirmed cases which all three samples were obtained, the sensitivity of MAT and IgM-ELISA was 97% (IC95%, 94-99%) and 96% (93-98%), respectively, when results of early and late acute-phase samples were evaluated in comparison to the results of the early acute and convalescent samples. In contrast, the sensitivity of MAT and IgM-ELISA was 44% (38-50%) and 75% (69-79%), respectively, when only a single early acute-phase sample was evaluated. Late acute-phase and convalescent-phase samples were obtained from 32% and 6% of the suspected leptospirosis and deaths, respectively. These findings indicate that collection and serologic testing of a late-acute-phase sample among hospitalized patients with suspected leptospirosis may significantly increase the efficiency of protocols for laboratory case confirmation.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-23T11:18:56Z No. of bitstreams: 2 Dissertação - Pedro Henrique Dias Botelho - 2017.pdf: 2156209 bytes, checksum: 7548059cd0e4b1077f097a09aa4fd4eb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-05-23T11:19:34Z (GMT) No. of bitstreams: 2 Dissertação - Pedro Henrique Dias Botelho - 2017.pdf: 2156209 bytes, checksum: 7548059cd0e4b1077f097a09aa4fd4eb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-05-23T11:19:35Z (GMT). No. of bitstreams: 2 Dissertação - Pedro Henrique Dias Botelho - 2017.pdf: 2156209 bytes, checksum: 7548059cd0e4b1077f097a09aa4fd4eb (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-20 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Introduction. Laboratory tests are essential for dengue diagnosis, in that sense algorithms are proposed, which proposes instructions for a more effective laboratory dengue diagnosis. Aim. To evaluate the performance of laboratory tests in the confirmation of suspected dengue cases, appling an algorithm, during a dengue epidemic in Goiânia, Central West Brazil 2012-2013. Methodology. This is a retrospective analytical observational study in a database of a prospective cohort with suspected dengue cases. The algorithm applied was based on three periods in the acute phase of disease, 0-3, 4-7 and >7 days after onset of symptoms (DOS) and in detection of immunoglobulins M and G (IgM and IgG), non-structural 1 protein antigen (NS1Ag) and viral RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). Positivity was seen individually and in association of tests in the algorithm and per day of infection, and used to confirm cases. The tests performance was evaluated by the sensitivity, specificity and accuracy of each test when compared to the others association, also in the algorithm. The results were statistically analyzed using SPSS Statistics 17.0, R software and OPENEPI. Results. 592 patients with suspected dengue were included, 415 (70.1%) were laboratory confirmed. In the 0-3 DOS period, the best positivities were by RT-PCR (81.6%) and NS1Ag (63.3%). While, IgM obtained the best positivities in 4-7 and >7 DOS periods (85.5% and 93.3%, respectively). Individually, RT-PCR and IgM tests were the most efficient to add positivity to diagnosis at the beginning and at the end of the acute phase of infection, respectively. Sensitivity results were similar to those of positivity, whereas NS1Ag specificities were greater than 90% at all periods. Conclusion. The algorithm sowed which laboratorial test was the best for the course of disease. Until 3 DOS, molecular is most sensitive test; between 4-7 DOS, two techniques may be required to obtain an accurate diagnostic. NS1Ag test, presented less detection in secondary infection cases, however, they was more specific test and can be used in differential diagnosis of dengue. These results contributed to diagnostic decision in the epidemiological context with concomitant arbovirus circulation. / Introdução. Testes laboratoriais são fundamentais para o diagnóstico da dengue, nesse sentido são propostos algoritmos, que propõe instruções para um diagnóstico laboratorial de dengue mais eficaz. Objetivo. Avaliar o desempenho de testes laboratoriais na confirmação de casos suspeitos de dengue, no curso de duas epidemias (2012 e 2013) em Goiânia, Goiás, Centro-Oeste do Brasil. Metodologia. Trata-se de um estudo observacional analítico que analisou uma base de dados clínicos e laboratoriais de uma coorte prospectiva de pacientes com suspeita clínica de dengue. O algoritmo aplicado baseou-se em três períodos da doença, 0-3, 4-7 e >7 dias após o início dos sintomas (DOS) e no uso de testes de detecção das imunoglobulinas M e G (IgM e IgG), do antígeno da proteína não-estrutural 1 (NS1Ag) e do RNA viral por reação em cadeia da polimerase via transcriptase reversa (RT-PCR). Foram avaliadas a positividade dos testes individualmente e em associação de testes por dia de infecção; e a sensibilidade, especificidade e acurácia dos testes. A análise estatistica usou os programas SPSS Statistics 17.0, R software e OPENEPI. Resultados. Dos 592 pacientes selecionados, 415 (70,1%) foram confirmados laboratorialmente. No período de 0-3 DOS, a RT-PCR e NS1Ag obtiveram 81,6% e 63,3% de positividade respectivamente. IgM obteve as positividade nos períodos de 4-7 e >7 DOS (85,5% e 93,3%, respectivamente). Individualmente, os testes de RT-PCR e IgM positividade ao diagnóstico no início e no final da fase aguda da infecção, respectivamente. Os resultados de sensibilidade foram semelhantes aos de positividade, enquanto os de especificidade de NS1Ag foram superiores à 90% em todos os períodos. Conclusão. O algoritmo apontou qual teste laboratorial foi o melhor para o curso da doença. Até 3 DOS, o teste molecular é o mais sensível; Entre 4-7 DOS, duas técnicas podem ser necessárias para obter um diagnóstico preciso. O teste de NS1Ag apresenta menor detecção em casos de infecção secundária, no entanto, foi o teste mais específico, podendo ser utilizado no diagnóstico diferencial de dengue. Estes resultados contribuíram para a decisão diagnóstica no contexto epidemiológico com a circulação concomitante de arbovírus.

Florida's mild climate supports year round enzootic transmission of arthropod-borne (arbo) viruses, such as St. Louis Encephalitis virus (SLEV), West Nile virus (WNV), and Eastern Equine Encephalomyelitis virus (EEEV). First isolated in 1960 from two Florida blue jays, Highlands J virus (HJV) is endemic to the state and vectored by the same mosquitoes as EEEV (Henderson et al, 1962). EEEV and HJV are both alphaviruses, but HJV is not pathogenic to humans, occasionally causes encephalitis in horses, and is a recognized pathogen in some bird species (turkeys, emus, etc) (Cilnis et al, 1996). The Florida Sentinel Chicken Arboviral Surveillance Program, established in 1978, utilizes sentinel chickens to detect arboviral activity throughout the state. Current serologic antibody detection methods include the hemagglutination inhibition (HAI), IgM antibody capture enzyme-linked immunosorbent (MAC-ELISA), and serum neutralization plaque reduction (PRNT) assays (Blackmore et al, 2003). In 2003, sentinel chickens detected significantly greater alphavirus activity than seen in the previous 15 years (Stark & Kazanis, 2003). This increase raised concerns that bridging into the human population had become a serious threat as well as an important issue for veterinary health. The objective of this study was to determine if cross-reactions with Highlands J virus were impacting the serologic diagnostic tests routinely performed for identification of EEEV. For 2003, the HAI test detected 476 alphavirus positive sentinels. We tested 316 of these chickens in the PRNT, which identified 176 EEEV positive sentinels and 75 HJV positive sentinels. Our results indicate that Highlands J virus is extensively cross-reactive in the HAI test and that the MAC-ELISA is more specific for the detection of antibodies solely to EEEV. We demonstrated that EEEV antibody titers in the HAI test were positively correlated to antibody titers in the PRNT assay. Analysis of alphaviral activity by county indicates widespread transmission of HJV across the northern and panhandle regions of the state; however EEEV activity was greater than HJV activity in all but four counties. Consequently, distinguishing between the two agents can reduce the expenditure of resources on unnecessary vector control and medical alerts to protect the public health from Highlands J virus.