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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

About «Factors determining irregular attendance to follow-up visits among human immunodeficiency virus patients: Results of a hospital survey of patients infected with human immunodeficiency virus, 2002-2012»

Guillermo Ladera, Dayana Sianny, Ventocilla Gonzales, Iris Janet 04 1900 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Cartas al editor / Revisión por pares
332

Migration crisis in Venezuela: impact on HIV in Peru

Rebolledo-Ponietsky, K, Munayco, C V, Mezones-Holguín, E 01 February 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Cartas al editor / Revisión por pares / Revisión por pares
333

Development and pre-clinical evaluation of HIV-1 vaccines

Mbewe-Mvula, Alice January 2017 (has links)
Infants born to HIV-1 positive mothers are at risk of acquiring the infection through pro-longed breastfeeding due to the presence of HIV-1 cell-free RNA and cell-associated DNA in breast milk. However, there is limited focus on vaccines to prevent mother-to-child transmission (MTCT) via breastfeeding. Mycobacterium tuberculosis (M. tuberculosis) the causative agent of Tuberculosis (TB) is the most common cause of AIDS-related deaths. Most infants in Africa receive Bacillus Calmette-Guérin (BCG) at birth or soon after birth and it is the only licensed vaccine for TB. The development of a dual platform vaccine against HIV-1 and TB would be a logical effort to combat these two deadly diseases. Thus, rBCG expressing an HIV-1 derived immunogen may induce HIV-1 responses at birth and these responses can be boosted at adolescence, by a heterologous vector such as modified vaccinia Ankara (MVA) or Chimpanzee adenovirus serotype 63 (ChAdV63). In the first study, I assessed BCG-based vaccines derived from BCG Danish SSI-1331 (BCG<sub>1331</sub>), expressing an HIV-1 immunogen HIVconsv either by an episomal plasmid (BCG.HIVconsv401<sup>epi</sup>) or integrated into the BCG chromosome (BCG.HIVconsv401<sup>int</sup>) in a prime-boost regimen. BALB/c mice were immunised with the different prime-boost regimens. rBCG alone was unable to induce detectable HIV-1-specific T-cell responses, however, when used in a prime-boost strategy, elevated HIV-1-specific T-cell responses were observed. In the second study, I aimed to construct marker-less mycobacterium-vectored HIV-1 vaccines using the operator-repressor titration (ORTA®) system as an alternative system for antibiotic resistance gene free vaccines. This rBCG vaccine would express the HIVconsv immunogen. I first constructed plasmids carrying the lac operator lacO and tetracycline operator tetO to enable use in ORT Escherichia coli (E.coli) and Mycobacterium strains, respectively. The ORT system was successful in E. coli and not in mycobacterium. I also constructed plasmids carrying mycobacterium essential genes that would allow for genetic manipulation in Mycobacterium and the use of ORT in mycobacterium. Although the plasmid construction was successful, in the end, genetic manipulations in Mycobacterium and the production of an ORT based BCG (ORT-VAC) was not successful. Finally, I evaluated the immunogenicity of conventional DNA plasmid pTH.HIVconsv compared to Semliki Forest virus replicon DREP.HIVconsv in rhesus macaques. Immunisations were done in a prime-boost strategy with heterologous vectors MVA or ChAdV63 delivering the same immunogen, HIVconsv. It was found that DREP.HIVconsv which was at least 20-fold lower dose than pTH.HIVconsv was capable of inducing comparable T-cell responses and in some experiments, the responses were superior to the conventional DNA plasmid pTH.HIVconsv.
334

Citocinas e a modulação da resposta imune durante a infecção pelo HIV : suscetibilidade à infecção e progressão para a AIDS

Medeiros, Rubia Marília de January 2016 (has links)
Décadas se passaram desde que os pesquisadores iniciaram investigações sobre a patogênese da infecção pelo HIV. Atualmente, é possível identificar vários desfechos clínicos após a exposição ao vírus, entre eles estão indivíduos expostos não infectados e indivíduos que após a infecção progridem rápida ou lentamente para a aids. No entanto, a identificação de fatores que permitam diferenciar e monitorar estes desfechos continua um desafio. Neste contexto, citocinas parecem ser marcadores promissores de acompanhamento da progressão para a aids. Neste estudo, avaliamos indivíduos HIVpositivo fenotipicamente (níveis plasmáticos das citocinas IL-2, IL-4, IL-6, IL-10, IL- 17A, TNF-α, IFN-γ) e geneticamente (variantes polimórficas) com o objetivo de contribuir para o melhor entendimento da patogênese da infecção e trazer novas perspectivas às questões clínicas e terapêuticas. Nossos resultados sugerem uma associação entre o aumento dos níveis plasmáticos de IL-6 e IL-10 no estágio pré-aids em progressores rápidos (p<0,05) e lentos para a aids (p<0,05). Assim, o aumento dos níveis de IL-6 e de IL-10 podem indicar um estado inflamatório crítico, podendo ser utilizados como marcadores do curso da infecção em indivíduos HIV-positivo. Os genótipos IL10-592 AA+AC (OR 1.89, IC 95% 1,10-3,14, p<0,01) e IL17A-692 TC+CC (OR 1.61, IC 95% 0,99-2,71, p<0,05) foram associados à susceptibilidade a infecção pelo HIV em indivíduos eurodescendentes. Além disso, quando analisados em conjunto, SNPs nos genes IL4, IL6, IL10 e TLR9 mostraram efeitos aditivos significativos (p<0,01). Já em indivíduos afrodescendentes, observou-se um efeito protetor dos genótipos TLR9-1237 TC+CC (OR 0.47, IC 95% 0,23-0,96, p = 0,038), e um efeito epistático significativo entre TLR9 e IL4 (p<0,01). Estes resultados contribuem para a compreensão dos mecanismos envolvidos na resposta imune à infecção pelo HIV. Nossas análises mostram que a origem étnica tem grande influência nas associações entre as variantes genéticas e os desfechos da infecção pelo HIV. Adicionalmente, verificou-se que análises de interação gênica, avaliadas através da redução multifatorial de dimensionalidade (MDR), contribuem para a compreensão dos efeitos dos SNPs e podem ser muito úteis na identificação de redes gênicas que influenciam na susceptibilidade e/ou em diferentes cursos clínicos da infecção pelo HIV. / Decades have passed since researchers began investigations on the pathogenesis of HIV infection. Currently, it is possible to identify many clinical outcomes after exposure to the virus, which includes individuals exposed but uninfected, and rapid or slow progressors to AIDS. However, the identification of factors that allows to differentiate and monitor these outcomes remains a challenge. In such context, cytokines seem to be promising markers for monitoring the progression to AIDS. This study evaluated phenotypically (plasmatic levels of cytokines IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, IFN-γ) and genetically (polymorphic variants) HIV-positive individuals as a contribution to a better understanding of the pathogenesis of infection and bring new perspectives to clinical and therapeutic issues. Our results suggest an association between increased serum levels of IL-6 and IL-10 in the pre-AIDS stage for rapid progressors (p<0.05), and for slow progressors to AIDS (p<0.05). Thus, the increase of IL-6 and IL-10 levels may indicate a critical inflammatory condition, and they can be used as course markers of infection in HIV-positive individuals. The genotypes IL10-592 AA+AC (OR 1.89, 95% CI 1.10-3.14, p<0.01) and IL17A-692 TC+CC (OR 1.61, 95% CI 0.99-2.71, p <0.05) have been associated with susceptibility to HIV infection in European-descendents individuals. Moreover, when analyzed together, SNPs in genes IL4, IL6, IL10 and TLR9 showed significant additive effects (p <0.01). Already in African-descendant individuals, a protective effect was observed in genotypes TLR9-1237 TC+CC (OR 0.47, 95% CI 0.23-0.96, p=0.038) and a significant epistatic effect between TLR9 and IL4 (p<0.01). These results contribute to the understanding mechanisms involved in the immune response to HIV infection. Furthermore, the analysis show that ethnic origin has a heavy influence on associations between genetic variants and the outcomes of infection by HIV. The interaction through the multifactor dimensionality reduction (MDR) contributed to the understanding the SNP effects and can be very useful to identify genes which has influence on susceptibility networks and / or different clinical courses.
335

Manifestações orais associadas ao HIV após 30 anos de epidemia no Brasil / HIV-oral related lesions after 30 years of epidemics in Brazil

Watanuki, Fernando 09 December 2010 (has links)
A epidemia de HIV/AIDS, que sofreu grandes mudanças em seus padrões clínicos e epidemiológicos, atingiu neste século sua estabilidade. Durante estes 30 anos os profissionais de saúde aprenderam muito sobre a doença e hoje esse aprendizado reflete-se em maior eficiência no diagnóstico e no tratamento da infecção pelo vírus e de suas manifestações oportunistas. As lesões orais associadas ao HIV são motivo de estudo desde os primeiros relatos da doença no início dos anos 80, e foram relacionadas ao sexo, idade, naturalidade, forma de exposição ao vírus e a padrões virológicos e imunológicos. Mas a pressão exercida pelas mudanças das características demográficas da epidemia sobre as manifestações bucais oportunistas do HIV não foi levada em consideração. A estabilidade da epidemia e o amadurecimento do conhecimento proporcionam um terreno propício para a avaliação da real prevalência dessas manifestações. Esta pesquisa tem como objetivo verificar como está este panorama no Brasil. Cento e quatro pacientes HIV+ em início de TARV foram avaliados clinicamente, e foram colhidos dados demográficos e exames laboratoriais, além da execução de sialometria e índice CPO-D. A população avaliada foi predominantemente masculina (78,8%) com média de 37,8 anos de idade. A via de transmissão do HIV foi sexual, sendo 57,7% através do sexo homo/bissexual e 38,4% com sexo heterossexual. 52,9 % souberam de sua soropositividade a menos de um ano. O CD4 médio foi de 223 céls/mm³ e a CV de 121.400 cópias/ml. As lesões extraorais foram diagnosticadas em 10,6% dos pacientes, sendo as hiperpigmentações de pele e mucosa (9,6%) e o aumento de glândulas salivares (0,96%) as lesões mais encontradas. A candidíase oral (49%) e a leucoplasia pilosa (41,3%) foram as lesões intraorais mais prevalentes. A xerostomia foi queixa de 46,6% e a hipossalivação foi diagnosticada em 18% e 48% dos pacientes, dependendo da metodologia utilizada para avaliação. O índice CPOD foi de 14,4, considerado alto pela OMS. A presença de lesões orais, candidíase e leucoplasia pilosa foram associadas à baixa imunidade e a presença de lesões orais e candidíase a cargas virais altas. A hipossalivação, avaliada através do fluxo salivar estimulado e representando principalmente a saliva da parótida, foi relacionado com níveis de CD8 alterados. Comparado com a literatura revisada, a prevalência de lesões orais associadas ao HIV apresenta-se alterada neste estudo, principalmente pela ausência de diagnóstico de neoplasias malignas e baixa prevalência de outras lesões orais associadas à aids. / HIV/AIDS epidemic, which has undergone major changes in their clinical and epidemiological patterns, in this century reached its stability. During these 30 years, much has been learned about the disease by health care professionals and nowadays, all this knowledge is reflected in greater efficiency in the diagnosis and treatment of virus infection and its opportunistic manifestations. HIV oral related lesions have been studied since the first reports of the disease in the earlies 80\'s, and were related to gender, age, place of birth, route of virus exposure, and virological and imunological patterns. Demographic changes of the disease over oral HIV opportunistic diseases have not been taken into consideration. The stability of epidemics and maturing of knowledge provide a fertile ground for the evaluation of the real prevalence of these manifestations. This research aims to verify this scenario in Brazil. A hundred and four HIV+ patients starting HAART were evaluated clinically, and demographic data and laboratory tests were collected, in addition to performing sialometry and DMFT index. The population was predominantly male (78,8%), average of 37,8 years old. The route of HIV transmission was sexual, 57,7% through homo/bisexual sex, and heterosexual sex, with 38,4%. 52,9% knew their HIV sero status to less than one year. The average CD4 was 223 cell/mm3 and CV of 121,400 copies/ml. Extra oral lesions were observed in 10,6% of patients, the skin and mucosal hyperpigmentation (9,6%) and enlargement of salivary glands (0,96%) were the lesions diagnosed. Oral candidiasis (49%) and oral hairy leukoplakia (41,3%) were the most prevalent intraoral lesions. Xerostomia was a complaining of 46,6% and hyposalivation was diagnosed in 18% and 48% of patients, depending on the methodology applied. The DMFT index was 14,4, considered high by WHO. Oral lesions, oral candidiasis and oral hairy leukoplakia were associated to low immunity and high viral load levels. Hyposalivation, evaluated by stimulated salivary flow (mainly, representing the saliva produced by parotid gland) was associated with altered levels of CD8. Compared to reviewed literature, oral lesions prevalence was considered altered in this research, notably the lack of diagnosis of malignant neoplasias and low prevalence of other lesions associated with aids. .
336

Manifestações orais associadas ao HIV após 30 anos de epidemia no Brasil / HIV-oral related lesions after 30 years of epidemics in Brazil

Fernando Watanuki 09 December 2010 (has links)
A epidemia de HIV/AIDS, que sofreu grandes mudanças em seus padrões clínicos e epidemiológicos, atingiu neste século sua estabilidade. Durante estes 30 anos os profissionais de saúde aprenderam muito sobre a doença e hoje esse aprendizado reflete-se em maior eficiência no diagnóstico e no tratamento da infecção pelo vírus e de suas manifestações oportunistas. As lesões orais associadas ao HIV são motivo de estudo desde os primeiros relatos da doença no início dos anos 80, e foram relacionadas ao sexo, idade, naturalidade, forma de exposição ao vírus e a padrões virológicos e imunológicos. Mas a pressão exercida pelas mudanças das características demográficas da epidemia sobre as manifestações bucais oportunistas do HIV não foi levada em consideração. A estabilidade da epidemia e o amadurecimento do conhecimento proporcionam um terreno propício para a avaliação da real prevalência dessas manifestações. Esta pesquisa tem como objetivo verificar como está este panorama no Brasil. Cento e quatro pacientes HIV+ em início de TARV foram avaliados clinicamente, e foram colhidos dados demográficos e exames laboratoriais, além da execução de sialometria e índice CPO-D. A população avaliada foi predominantemente masculina (78,8%) com média de 37,8 anos de idade. A via de transmissão do HIV foi sexual, sendo 57,7% através do sexo homo/bissexual e 38,4% com sexo heterossexual. 52,9 % souberam de sua soropositividade a menos de um ano. O CD4 médio foi de 223 céls/mm³ e a CV de 121.400 cópias/ml. As lesões extraorais foram diagnosticadas em 10,6% dos pacientes, sendo as hiperpigmentações de pele e mucosa (9,6%) e o aumento de glândulas salivares (0,96%) as lesões mais encontradas. A candidíase oral (49%) e a leucoplasia pilosa (41,3%) foram as lesões intraorais mais prevalentes. A xerostomia foi queixa de 46,6% e a hipossalivação foi diagnosticada em 18% e 48% dos pacientes, dependendo da metodologia utilizada para avaliação. O índice CPOD foi de 14,4, considerado alto pela OMS. A presença de lesões orais, candidíase e leucoplasia pilosa foram associadas à baixa imunidade e a presença de lesões orais e candidíase a cargas virais altas. A hipossalivação, avaliada através do fluxo salivar estimulado e representando principalmente a saliva da parótida, foi relacionado com níveis de CD8 alterados. Comparado com a literatura revisada, a prevalência de lesões orais associadas ao HIV apresenta-se alterada neste estudo, principalmente pela ausência de diagnóstico de neoplasias malignas e baixa prevalência de outras lesões orais associadas à aids. / HIV/AIDS epidemic, which has undergone major changes in their clinical and epidemiological patterns, in this century reached its stability. During these 30 years, much has been learned about the disease by health care professionals and nowadays, all this knowledge is reflected in greater efficiency in the diagnosis and treatment of virus infection and its opportunistic manifestations. HIV oral related lesions have been studied since the first reports of the disease in the earlies 80\'s, and were related to gender, age, place of birth, route of virus exposure, and virological and imunological patterns. Demographic changes of the disease over oral HIV opportunistic diseases have not been taken into consideration. The stability of epidemics and maturing of knowledge provide a fertile ground for the evaluation of the real prevalence of these manifestations. This research aims to verify this scenario in Brazil. A hundred and four HIV+ patients starting HAART were evaluated clinically, and demographic data and laboratory tests were collected, in addition to performing sialometry and DMFT index. The population was predominantly male (78,8%), average of 37,8 years old. The route of HIV transmission was sexual, 57,7% through homo/bisexual sex, and heterosexual sex, with 38,4%. 52,9% knew their HIV sero status to less than one year. The average CD4 was 223 cell/mm3 and CV of 121,400 copies/ml. Extra oral lesions were observed in 10,6% of patients, the skin and mucosal hyperpigmentation (9,6%) and enlargement of salivary glands (0,96%) were the lesions diagnosed. Oral candidiasis (49%) and oral hairy leukoplakia (41,3%) were the most prevalent intraoral lesions. Xerostomia was a complaining of 46,6% and hyposalivation was diagnosed in 18% and 48% of patients, depending on the methodology applied. The DMFT index was 14,4, considered high by WHO. Oral lesions, oral candidiasis and oral hairy leukoplakia were associated to low immunity and high viral load levels. Hyposalivation, evaluated by stimulated salivary flow (mainly, representing the saliva produced by parotid gland) was associated with altered levels of CD8. Compared to reviewed literature, oral lesions prevalence was considered altered in this research, notably the lack of diagnosis of malignant neoplasias and low prevalence of other lesions associated with aids. .
337

Manifestações bucais da AIDS e o perfil de mutações e de resistência do HIV em pacientes experimentando falha terapêutica / Oral manifestations of AIDS and the profile of HIV mutations and resistance in patients undergoing treatment failure

Catalina Riera Costa 10 December 2013 (has links)
As manifestações bucais da AIDS têm sido relacionadas a diversas características clínicas da infecção pelo HIV como decréscimo de células T CD4+, aumento de carga viral e falha terapêutica, entre outras. Os avanços recentes da medicina mostram que a falha terapêutica, nesses pacientes, está diretamente vinculada a mutações na transcriptase reversa (TR) e na protease (PR). O objetivo deste estudo foi descrever, em pacientes HIV+ apresentando falha terapêutica, o perfil de mutações do vírus e o perfil de resistência a antirretrovirais, e correlacioná-los as manifestações bucais da imunodeficiência. Foram acessados prontuários, laudos de genotipagem e informações de bancos de dados digitais de pacientes com AIDS, que se submeteram a genotipagem no Centro de Referência e Treinamento em Doenças Sexualmente Transmissíveis e AIDS (CRT-DST/AIDS), entre 2003 e 2010. Os dados foram transferidos para o Epiinfo, onde foi construído um banco de dados informatizado para posterior análise estatística. O evento lesões orais foi escolhido como variável dependente. Calculou-se o odds ratio para cada variável independente, utilizando intervalo de confiança de 95%. Foram cruzados dados sobre mutações encontradas no vírus e resistência às medicações com a presença e tipo de manifestações bucais. O teste de Bartlett foi utilizado para testar a normalidade dos dados. Para variáveis sem distribuição normal foram aplicados os testes de Mann-Whitney ou Kruskal-Wallis. Para comparação entre frequências e proporções, foi utilizado o Teste de Exato de Fisher ou o Qui quadrado. O nível de significância foi estabelecido como 0,05 ou 5%. A análise de características sociocomportamentais e clínico laboratoriais permitiu verificar que a presença de lesões orais pode ser relacionada estatisticamente a baixas taxas de CD4 (p<0,05), faixa de carga viral (p=0,048) e ao uso prévio de mais de cinco esquemas antirretrovirais diferentes (p=0,021). Verificou-se maior prevalência de lesões virais (75%) e bacterianas (66,7%) do que de lesões fúngicas (37,3%) apenas em pacientes que apresentavam resistência a inibidores de protease (IP) (p=0,02). Foram encontradas 146 mutações diferentes nos pacientes que apresentavam lesões orais, dentre essas, quatro (101E, 20T, 188L, 93L) apresentaram correlação negativa com a presença de lesões orais (respectivamente, p=0,01, p=0,01, p=0,03, p=0,03) e oito (215Y, 118I, 20R, 44D, 71I, 82I E 84V) apresentaram correlação positiva (respectivamente p=0,04, p=0,05, p=0,03, p=0,01, p=0,01, p=0,04, p=0,0004). Subsequentemente, as mutações que apresentaram correlação positiva com a presença de lesões orais foram avaliadas para verificar se sua presença estaria realmente associada a resistência aos ARVs (aos quais seriam supostamente resistentes). Foram excluídas dessa avaliação as mutações 71I e 82I, por apresentarem uma quantidade extremamente pequena de ocorrências. Todas as mutações apresentaram correlação estatística positiva para a resistência aos respectivos antirretrovirais (p<0,05). Em pacientes HIV+, que apresentavam falha terapêutica e manifestações bucais, foram identificadas as mutações 84V e 20R na PR e as mutações 215Y, 44D e 118I na TR e a presença dessas mutações foi associada a resistência a inibidores de protease e inibidores de transcriptase reversa nucleosídeos, respectivamente. / Oral manifestation of AIDS have been associated with several clinical characteristics of HIV infection such as reduction in T CD4+ cells, increase in viral load and treatment failure, among others. Recent advances have shown that treatment failure in these patients is directly linked to mutations in reverse transcriptases (RT) and in proteases (PR). The objective of the present study was to describe the profile of virus mutations and of resistance to antiretroviral drugs in HIV+ patients in treatment failure, and to correlate mutations to the oral manifestations of the immunodeficiency. Patient charts, genotyping results and information from digital databases of AIDS patients, who underwent genotyping at the Sexually Transmissible Diseases and AIDS Training and Reference Center (CRT-DST/AIDS) between 2003 and 2010, were accessed. Data were transferred to the Epiinfo program, in which a computerized database was built for statistical analysis. The event oral lesions was chosen as a dependent variable. Odds ratio for each independent variable was calculated, using a 95% confidence interval. Data found on virus mutations and drug resistance was analyzed to check for correlation with presence and type of oral manifestations. The Bartlett test was used to test normality of data. Mann-Whitney or Kruskal-Wallis tests were used for variables without a normal distribution. The Fisher Exact or Chi-square Tests were used to compare frequencies and proportions. A 0.05 or 5% significance level was established. The analysis of socio-behavioral and clinical-laboratorial characteristics allowed concluding that the presence of oral lesions may be related to statistically low CD4 rates (p<0.05), viral load range (p=0.048) and previous use of more than five different antiretroviral regimens (p=0.021). A higher prevalence of viral (75%) and bacterial (66.7%) lesions in relation to fungal lesions (37.3%) was observed only in patients who were resistant to protease inhibitors (PI) (p=0.02). We found 146 different mutations in patients with oral lesions, among which, four (101E, 20T, 188L, 93L) with a negative correlation with the presence of oral lesions (p=0.01, p=0.01, p=0.03, p=0.03, respectively) and eight (215Y, 118I, 20R, 44D, 71I, 82I E 84V) with a positive correlation (p=0.04, p=0.05, p=0.03, p=0.01, p=0.01, p=0.04, p=0.0004, respectively). Subsequently, mutations with a positive correlation with the presence of oral lesions were assessed to check if their presence would really be associated with resistance to ARVs (to which they supposedly would be resistant to). Mutations 71I and 82I were excluded from this assessment because they had an extremely low frequency. All mutations had a statistically positive correlation for resistance to their respective antiretroviral drugs (p<0.05). Mutations 84V and 20R were identified in PR, and mutations 215Y, 44D and 118I in TR of HIV+ in patients undergoing treatment failure and presenting oral manifestations. Moreover, the presence of these mutations was associated with resistance to protease inhibitors and to nucleoside reverse transcriptase inhibitors, respectively.
338

Subtipos do HIV-1 e associação com características demográfico-epidemiológicas em pacientes atendidos em Hospital de referência em Porto Alegre, Brasil

Pereira, Patrícia Reis January 2010 (has links)
O HIV é dividido em HIV-1 e 2. O HIV-1 é classificado em três grupos, o M (main) responsável pela maioria das infecções, O (outlier) e N(new). Na atualidade, nove subtipos puros e 43 formas recombinantes do grupo M são reconhecidos incluindo sub subtipos. O subtipo C é o mais prevalente, representando aproximadamente 56% das infecções no mundo. Não foram descritas as conseqüências exatas destes subtipos, algumas evidências indicam que alguns subtipos podem ter vantagem na transmissão viral, enquanto outros na replicação, além de influenciar nas vias de mutação, aparecimento de resistência mais rapidamente e fracasso do tratamento. No Brasil os subtipos B e C são os mais freqüentes e acima de 50% dos indivíduos recentemente infectados pertencem aos subtipos não-B. O Rio Grande do Sul (RS) exibe a prevalência mais alta do subtipo C e há uma forma recombinante específica C e B – CRF-31. Entre julho de 2002 e janeiro de 2003 foi realizada a genotipagem e subtipagem do vírus HIV-1 em 178 pacientes, consecutivamente, atendidos no ambulatório de HIV/AIDS do Hospital de Clínicas de Porto Alegre (HCPA) desde 1983, os quais assinaram o termo de consentimento livre e informado. Após revisão dos resultados destes testes restaram 161 pacientes devido a perda de dados relacionados a nome e prontuário (não foi possível relacionar as 17 amostras a um nome e/ou prontuário). Em busca das variáveis demográficas e epidemiológicas realizou-se revisão de prontuário e busca ativa através de telefonema aos pacientes sem seguimento por pelo menos 2 anos. Consultou-se também o obituário de HIV/AIDS. O objetivo principal deste estudo é avaliar os padrões variáveis do HIV-1, prevalência nos indivíduos assistidos no Hospital de Clínicas de Porto Alegre e relacionar estes subtipos com características demográficas e epidemiológicas. Dos 161 pacientes, 90 eram do sexo masculino e 71 do sexo feminino. O subtipo B foi o mais prevalente em nossa amostra sendo encontrado em 53% dos pacientes. Até 1990 o subtipo B era encontrado na grande maioria dos pacientes com HIV, contribuindo com 75% das infecções. A partir de 2000 o subtipo C passou a representar a maioria das infecções, ficando com 33,3% dos casos, porém este aumento não foi estatisticamente significativo. Dos 161 pacientes com subtipo identificado, 19 não se conhecia a categoria de exposição. Revelando entre o subtipo B, a grande maioria dos pacientes nas categorias de exposição sexual, subdivisão homossexual e bissexual, o subtipo C foi relacionado com categorias de exposição heterossexual e uso de drogas injetáveis, quando se analisou separadamente o subtipo C com as categorias de exposição, não se demonstrou relação com categoria específica. Já o subtipo B analisado separadamente mostrou grande associação com a categoria de exposição MSM e bissexual. Em relação a procedência dos pacientes, houve associação estatisticamente significativa entre o subtipo B e a cidade de Porto Alegre, onde o mesmo foi encontrado na maioria dos pacientes. O subtipo C foi encontrado na maioria dos pacientes procedentes de regiões metropolitanas e do interior do estado. O conhecimento da prevalência dos subtipos de acordo com a procedência dos pacientes pode ajudar as autoridades competentes a dirigir esforços na prevenção da infecção pelo HIV.
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Vasculitides in HIV-infected children: a case series & literature review

Dempoulos, Despina 27 January 2012 (has links)
M.Med.(Paediatrics), Faculty of Health Sciences, University of the Witwatersrand, 2011 / Medium and large vessel vasculopathy in HIV-infected patients is an uncommon but important cause of mortality and morbidity in both adult and paediatric patients. The estimated frequency in children from the current literature is 1-2%. The overall HIV prevalence among children 18 years of age and younger in South Africa is currently 2.9%. This series reports on medium and large vessel vasculopathy in children with HIV. Six HIV infected children seen at three Johannesburg hospitals between 2000 -2006, are described, all presenting with complications arising from medium and/or large vessel involvement. Additional cases are reviewed from the literature. A description of the clinical presentation, radiological investigations, the possible aetiology, pathophysiology and management of these patients is presented. The case series and literature review compares HIV vasculopathy and Takayasu’s arteritis. Both entities can present with multiple aneurysms and a diagnosis of tuberculosis, thus a possible link in the pathogenesis is explored. Most patients with HIV vasculopathy present while severely immunosuppressed. However, some patients in the case series and literature review present despite adequate viral suppression, suggesting the possibility of an immune-reconstitution inflammatory syndrome in the pathogenesis of this vascular complication. Medical management and in selected cases, surgery, has been used in the management of patients with HIV vasculopathy. The outcomes thus far are good.
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The prevalence of parvovirus B19 infection in a cohort of HIV infected patients with severe anaemia

Glatt, Nadia January 2017 (has links)
A Research Report submitted to the Faculty of Health Sciences, University of Witwatersrand, Johannesburg in part fulfillment of the requirements for the degree of Masters of Medicine in the branch of Haematology Johannesburg, / Parvovirus B19, a single stranded deoxyribose nucleic acid (DNA) virus, is known to cause anaemia in the setting of immune suppression such as Human Immunodeficiency Virus (HIV) infection. It is typically associated with a severe, isolated, normochromic normocytic anaemia and reticulocytopenia. The bone marrow classically shows a pure red cell aplasia (PRCA) with absence of maturing erythropoiesis, giant pronormoblasts and a variable presence of erythroid viral inclusions. Parvovirus B19 infection is a treatable cause of anaemia using red cell transfusions, intravenous immunoglobulin (Ig) therapy and in the setting of HIV, antiretroviral therapy. In the setting of HIV infection, testing for Parvovirus B19 infection using molecular techniques such as polymerase chain reaction (PCR) are preferred over serological methods, as antibodies are either not made or are dysfunctional. In South Africa, the prevalence of Parvovirus B19 infection in the HIV infected population with severe anaemia is not known. The aim of this study was to assess the prevalence of Parvovirus B19 in a cohort of HIV infected patients with severe anaemia. The Inclusion criteria for specimens into the study included all specimens submitted for a bone marrow examination submitted for routine diagnostic workup between January 2012 and November 2013 at two academic hospitals in Johannesburg. The study population included HIV infected patients with severe anaemia, defined as haemoglobin levels <8 g/dl for men and non-pregnant women. Real-time PCR using the PrimerDesign™ genesig® Kit for Human Parvovirus B19 (Southampton, United Kingdom) was performed on DNA extracted from bone marrow aspirate slides of these patients. The Parvovirus B19 results (qualitative and semi-quantitative values) were assessed in conjunction with various Parvovirus B19-related clinical and laboratory parameters obtained from the laboratory information system (LIS). The prevalence of Parvovirus B19 in this cohort of patients was 13.3% (19/143). PCR testing was possible even in samples that were suboptimal for morphological assessment, with 36.8% (7/19) of the Parvovirus B19 infection being observed in these samples. Of note, 31.6% (6/19) of the positive samples were not requested for Parvovirus B19 testing by the clinician or pathologist, indicating that it is being under diagnosed in this population. PRCA was not observed in all Parvovirus B19 positive samples, with a sensitivity and specificity of 60.0% and 85.1% respectively. Alternate causes of anaemia were present in 42.1% (8/19) of the Parvovirus B19 positive samples, including 21.1% (4/19) of cases which showed Mycobacterium Tuberculosis infection, 5.3% (1/19) with iron deficiency and 15.8% (3/19) of cases with marrow infiltration by malignancy. This highlights the importance of excluding Parvovirus B19 infection even in the setting of alternate causes of anaemia. In patients with severe anaemia and both HIV infection and Parvovirus B19-positivity, there was no statistically significant correlation between Parvovirus B19 viral load and HIV viral load, haemoglobin (Hb) level or CD4 count. Parvovirus B19 positivity was higher than expected in HIV virally suppressed patients, with a prevalence of 18.5% (5/27). However the CD4 counts in these samples were low (<350 cells/μl), suggesting that although viral suppression had been achieved, there was inadequate immune reconstitution to mount an effective humoral response to control the Parvovirus B19 infection. Serology for IgM as a method for diagnosing Parvovirus B19 infection showed poor sensitivity (60%) but good specificity (100%) suggesting that this is an inadequate screening test in the setting of HIV infection. The Parvovirus B19 positive samples had statistically significant lower reticulocyte production index (RPI) than the Parvovirus B19 negative samples. The negative predictive value of an RPI was 100%. Although this is a retrospective pilot study, notable findings were observed. In the setting of HIV infection and severe anaemia, Parvovirus B19 infection may be diagnosed by PCR even in the following scenarios: a negative IgM serology result, no morphological evidence of a PRCA, presence of other causes to explain the anaemia and confirmed HIV viral suppression. Parvovirus B19 is a treatable cause of anaemia and therefore an important entity to exclude. The cost of molecular diagnosis of parvovirus B19 is relatively higher than using serological methods, therefore should only be performed in the correct clinical setting. In HIV infected patients with grade four anaemia (Hb <6g/dl) and a reduced RPI, these findings support the use of molecular diagnosis for Parvovirus B19 infection regardless of other clinical and laboratory findings. / MT2017

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