Estudo de homogeneidade dos soros utilizados em controle de qualidade interno de testes imunodiagnósticos de HIV/Aids / AidsHomogeneity study of the internal quality control sera for immunodiagnosis of HIV/AIDS

Introduction: The present study reports the data from the first homogeneity assessment of samples composing the serum panels produced at the Immunology Center of Instituto Adolfo Lutz, São Paulo. These samples have been distributed to the public laboratories and those partaking in the Brazilian Unified Health System, and to the participants in the Internal Quality Control Program for human immunodeficiency virus (HIV) antibody (Ab) testing. Objective: To assess the homogeneity of serum samples in panels from different lots for HIV/acquired immunodeficiency syndrome (AIDS) immunodiagnosis by using the statistical method to ensure quality of the reference material. Method: Sera homogeneity was evaluated by means of enzyme-linked immunoassay/enzyme immunoassay (ELISA/EIA) for detection of HIV Ab, and the one-way analysis of variance was employed for analyzing the data. No statistically significant differences were found among the several serum vials. Conclusion: The sera dispensed in the vials were homogeneous in the respective lots...

Introdução: No presente estudo estão descritos os resultados das primeiras análises feitas sobre a avaliação da homogeneidade das amostras componentes de painéis de soros produzidos no Centro de Imunologia do Instituto Adolfo Lutz e distribuídos aos laboratórios públicos e conveniados ao Sistema Único de Saúde e participantes do Programa de Controle de Qualidade Interno para imunodiagnóstico de vírus da imunodeficiência humana/síndrome da imunodeficiência adquirida (HIV/AIDS). Objetivo: Avaliar a homogeneidade das amostras de soro componentes de painéis de diferentes lotes para imunodiagnóstico de HIV/Aids por meio de método estatístico para garantir a qualidade do material de referência. Material e método: A homogeneidade das amostras de soro foi avaliada por meio de enzyme-linked immunoassay/enzyme immunoassay (ELISA/EIA) para detecção de anticorpos anti-HIV, e os resultados foram submetidos à análise de variância fator único. Não foram encontradas diferenças significativas entre os resultados obtidos para os diversos frascos de soro. Conclusão: As amostras distribuídas nos frascos foram homogêneas entre si nos respectivos lotes...

An unusual seroconversion profile in a pregnant woman infected with the human immunodeficiency virus-1: need for using later generations HIV screening assays.

The first HIV-1 marker that appears in blood following infection is HIV-1 RNA and usually the load is in millions of copies/ ml preceding seroconversion. A 24-year-old pregnant woman, gravida 2, parity 1 was tested for HIV as part of antenatal screening. Three samples were collected and tested from this individual over a period 70 days. The HIV-1 RNA level during seroconversion phase was very low, contrary to the well understood natural history of HIV infection. The reactivity rate in the ELISA and the Western Blot profile showed a gradual increase over the 70 days with a weak reactivity in a second generation assay (detects IgG only) for the third sample. This case illustrates the uncertainties regarding the serological window period in HIV infection and the need to use at least a third generation assay in testing centres for early detection of HIV infection.

Estigma, discriminação e HIV/Aids no contexto brasileiro, 1998 e 2005 / Stigma, discrimination and HIV/AIDS in the Brazilian context, 1998 and 2005

OBJETIVO: Identificar a prevalência de atitudes discriminatórias em dois momentos da epidemia brasileira de HIV/Aids e possíveis mudanças ocorridas. MÉTODOS: O Índice de Intenção de Discriminação foi obtido por pontuação, somando 1 para situações de discriminação ou 0, para o caso contrário. As faixas de intenção de discriminação foram estabelecidas por meio da técnica de cluster, compatibilizadas entre os estudos de 1998 e 2005. Para verificar associação entre o índice e as variáveis sociodemográficas, utilizou-se comparações de médias, teste qui-quadrado, e modelos ajustados de regressão logito ordenado. RESULTADOS: Houve redução estatisticamente significante na proporção de pessoas entre as pesquisas de 1998 e 2005 que responderam sim à obrigatoriedade do teste anti-HIV para: a admissão no emprego, antes do casamento, ingresso nas forças armadas, usuários de drogas, entrada de estrangeiros no país, profissionais do sexo e para todas as pessoas. Possuir menor escolaridade, ser do sexo feminino, ter acima de 45 anos e residir na região Norte/Nordeste são fatores associados ao maior nível de intenção de discriminação. CONCLUSÕES: O crescimento da intenção de discriminação mostra que as informações sobre formas de transmissão e não transmissão da Aids ainda necessitam de melhor elaboração e divulgação, principalmente entre as populações de menor escolaridade, residentes nos estados do Norte/Nordeste, do sexo feminino e pertencentes à faixa etária acima de 45 anos.

OBJECTIVE: To identify discriminatory attitudes in two moments of the Brazilian HIV/AIDS epidemic, as well as the occurrence of possible changes. METHODS: The Intention of Discrimination Index was obtained by scoring 1 for discriminatory situations or 0, when the opposite was the case. Intention of discrimination ranges were established by means of the clustering technique, and made compatible between the 1998 and 2005 surveys. Mean comparisons, chi-square test and ordered logit adjusted regression models were used to verify association between the index and socio-demographic variables. RESULTS: Between the 1998 and 2005 surveys, there was a statistically significant reduction in the proportion of people who answered "yes" to anti-HIV test's being mandatory in the following cases: admission for employment, before getting married, when joining the military service, drug users, foreigners entering the country, sex professionals, and for all the people. To have lower level of education, to be female, to live in the North/Northeast regions of Brazil, and to be aged over 45 years are factors associated with higher intention of discrimination level. CONCLUSIONS: The growth of intention of discrimination shows that information about ways of AIDS transmission and non-transmission still needs to be better planned and promoted, especially among populations that have lower level of education, live in the North/Northeast regions, are female and aged over 45 years.

Evaluation of the concomitant use of two different EIA tests for HIV screening in blood banks

OBJECTIVE: In 1998, the Brazilian Ministry of Health made it mandatory for all blood banks in the country to screen donated blood for human immunodeficiency virus (HIV) concomitantly using two different enzyme immunoassay (EIA) tests. Concerned with the best use of available resources, our objective with this study was to evaluate the usefulness of conducting two EIA screening tests instead of just one. METHODS: We analyzed data from 1999 through 2001 obtained by testing 698 191 units of donated blood using two EIA HIV screening tests concomitantly at the Pro-Blood Foundation/Blood Center of Säo Paulo (Fundaçäo Pró-Sangue/Hemocentro de Säo Paulo), which is a major blood center in the city of Säo Paulo, Brazil. All samples reactive in at least one of the two EIA tests were submitted for confirmation by a Western blot (WB) test, and the persons who had donated those samples were also asked to return and provide a follow-up sample. RESULTS: Out of the 698 191 blood units that were donated, 2 718 of them (0.4 percent) had to be discarded because they were reactive to at least one of the EIA tests. There were two WB-positive donation samples that were reactive in only one HIV EIA screening test. On their follow-up samples, both donors tested WB-negative. These cases were considered false positive results at screening. Of the 2 718 donors who were asked to return and provide a follow-up sample, 1 576 of them (58 percent) did so. From these 1 576 persons, we found that there were two individuals who had been reactive to only one of the two EIA screening tests and who had also been negative on the WB at screening but who were fully seroconverted on the follow-up sample. We thus estimated that, in comparison to the use of a single EIA screening test, the use of two EIA screening tests would detect only one extra sample out of 410 700 units of blood. CONCLUSIONS: Our data do not support the use of two different, concomitant EIA screening tests for HIV. The great majority of HIV-positive donors have already seroconverted and will be detected using only a single EIA screening test. Only persons who are going through the process of seroconversion may be missed by using a single EIA test and detected using two EIAs for screening. To screen out these individuals and decrease the residual risk of HIV transmission from the blood donated in our center, the use of other techniques, such as nucleic acid testing (NAT) or a p24 antigen assay, would be more effective

Posición sobre los estudios serológicos de la infección por virus de inmunodeficiencia humana / Statement about serologic screening for human immunodeficiency virus infection

At present there are adecuate tests for diagnosing VIH infection, both for screening (ELISA) and confirmation (western blot) purpose. Polimerase chain reaction (PCR) and P24 antigen tests can be used for viral detection in infants before the age of 18 months (including neonatal period), before antibody seroconversion and in serologically indetermined cases. The Chilean Infectious Disease Society Advisory Committee on AIDS (CC-SIDA) strongly recommends that the following principles be followed in ordering/performing HIV diagnostic tests: informed consent (although under unusual and restricted circumstances in which the well being of third parties is involved this requirement can be waived), confidentiality of the information. Professional councelling before and after test is performed. For public health purposes it should be performed in all blood, blood products and germinative tissue as well as organ and tissue donation. It should also be performed anonymously in various population to monitor the evolution of the epidemic. Pregnant women should be encouraged to have the test performed in order to minimize vertical transmission through antiretroviral therapy. In non health care settings it should not be performed. Specifically it should not be a requirement in applying for job or education, obtainig life or health insurances, visa or authorization for crossing frontiers

La microbiología en la transfusión sanguínea / Microbiology in blood transfusion

La familia de los Retrovirus se encuentra en el hombre y en los animales y son una causa considerable de mortalidad. Aunque se sabe que existen hace casi 100 años, su rol como agentes patógenos humano se recononoció hace aproximadamente 15 años. Su Genoma está compuesto por ARN. Los cuadro Retrovirus humanos: HIV-1, HIV-2, HTLV-1 y HTLV-II comparten cararterísticas comunes aunque se trata de entidades diferentes. Los ensayos que se utilizan para cada uno de estos virus son similares tanto en los principios como en las técnicas. En este primer apartado (I) del ensayo "Los Retrovirus" de detallará: etipatología, configuración antigénetica, respuesta inmune específica del huésped, clasificación de los métodos de diagnósticos sérico de HIV-1 y HIV-2 luego se completará el dictum mediante una lista parcial de los equipos comerciales de diagnóstico en el Anexo 1

¿Quién cuida de las mujeres...? El VHI/SIDA en la atención pública de la salud. Síntesis de investigación / Who looks after the women...? The HIV/AIDS in the public care of health. Research summary

Con el objetivo de indagar acerca de las nociones de maternidad y de sida en el personal de salud que atiende a pacientes embarazadas infectadas con vih/sida que solicitan atención obbstétrica en los consultorios externos, se realizó una investigación antropológica en hospitales muncipales de la ciudad de Buenos Aires. A través de una metodología cualitativa basada en la observación y en las entrevistas semiestructurales, se llevó a cabo una investigación exploratoria que permitió identificar problemas en la atención cotidiana a las pacientes en los servicios de obstetricia e infectología en un hospital polivalente y una maternidad municipal.

Técnica de inmunofluorescencia para HIV-1 en un Centro de Referencia de la provincia de Buenos Aires / Immunofluorencence technique for HIV-1 at a Reference Center of Buenos Aires province (Argentina)

Se comprobó que la técnica de inmunofluorescencia indirecta (IFI) con células H9, puede usarse como método confirmatorio para muestras repetidamente reactivas por pruebas de screening (enzimoinmunoensayo). Se evaluaron 99 sueros por IFI según la técnica del Centro Nacional de Referencia para Diagnóstico e Investigación del SIDA, que previamente habían sido seleccionados contra el virus de la inmunodeficiencia humana (HIV) y confirmados por la técnica de Western Blot (WB). Se incluyeron 4 sueros con screening discordante, 2 con valor de corte bajo respecto del cutoff y 1 con screening negativo. Los sueros eran de pacientes de alto riesgo: drogadictos endovenosos 60; homosexuales 5; bisexuales 5; promiscuos 1; heterosexuales en contacto con HIV positivos 7; niños hijos de HIV positivos 6; transfundidos 2 y no refieren datos 13. Por técnica de WB resultaron positivos 89 sueros (89.9%), indeterminados 7 (7.1%) y negativos 3 (3.0%). Por IFI resultaron positivos 79 sueros (79.8%),inespecíficos 2 (2.9%), indeterminados 4 (4.0%) y negativos 14 (14.1%). Un suero positivo por IFI resultó indeterminado por WB. Se hicieron controles positivos y negativos no presentando falsa reactividad. La coincidencia entre ambos métodos fue del 86%. El objetivo fue dar una medida del poder predictivo de IFI como predictor de WB. Se utilizó el criterio Lambda de Goodman-Kruskal, que mide cuánto disminuye el porcentaje de error cuando se usa IFI como predictor de WB, comparado con el predictor consistente en asignar a todos los casos el resultado positivo. Para los datos disponibles se obtiene Lambda = 0.69

Implicaçöes éticas da triagem sorológica do HIV / Ethical implications of HIV sorological screening

A AIDS tem colocado em discussäo posiçöes éticas do profissional de saúde, tidas como indubitáveis, como o segredo médico ante a saúde de terceiros e a coletividade. Somado a este, outros problemas pertinentes à própria doença, como sua sorologia e tratamento, têm suscitado polêmica. Diante destas questöes, aborda algumas situaçöes de triagem sorológica e a conduta ética que deve normatizá-las (AMSB)