RESUMO
OBJECTIVE: HIV seroconversion biomarkers are being used in cross-sectional studies for HIV incidence estimation. Bio-Rad Geenius HIV-1/2 Supplemental Assay is an immunochromatographic single-use assay that measures antibodies (Ab) against multiple HIV-1/2 antigens. The objective of this study was to determine whether the Geenius assay could additionally be used for recency estimation. DESIGN: This assay was developed for HIV-1/2 confirmation; however, quantitative data acquired give information on increasing concentration and diversity of antibody responses over time during seroconversion. A quantitative threshold of recent HIV infection was proposed to determine "recent" or "nonrecent" HIV infection; performance using this cutoff was evaluated. METHODS: We tested 2500 highly characterized specimens from research subjects in the United States, Brazil, and Africa with well-defined durations of HIV infection. Regression and frequency estimation were used to estimate assay properties relevant to HIV incidence measurement: mean duration of recent infection (MDRI), false-recent rate, and assay reproducibility and robustness. RESULTS: Using the manufacturer's proposed cutoff index of 1.5 to identify "recent" infection, the assay has an estimated false-recent rate of 4.1% (95% CI: 2.2 to 7.0) and MDRI of 179 days (155 to 201) in specimens from treatment-naive subjects, presenting performance challenges similar to other incidence assays. Lower index cutoffs associated with lower MDRI gave a lower rate of false-recent results. CONCLUSIONS: These data suggest that with additional interpretive analysis of the band intensities using an algorithm and cutoff, the Geenius HIV-1/2 Supplemental Assay can be used to identify recent HIV infection in addition to confirming the presence of HIV-1 and HIV-2 antibodies.
Assuntos
Cromatografia de Afinidade/métodos , Testes Diagnósticos de Rotina/métodos , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1/imunologia , HIV-2/imunologia , África , Algoritmos , Brasil , Infecções por HIV/virologia , Incidência , Modelos Teóricos , Estudos Retrospectivos , Estados UnidosRESUMO
Introducción: el estudio de la estabilidad de los componentes y el producto terminado constituye un importante requisito regulatorio en los diagnosticadores. Objetivo: realizar un estudio de estabilidad en tiempo real durante doce meses del sistema inmunoenzimático (ELISA) DAVIH VIH-2. Métodos: se realizó un estudio de estabilidad en tiempo real durante doce meses en tres lotes del diagnosticador DAVIH VIH-2, ELISA indirecto diseñado para la detección de anticuerpos contra el virus de inmunodeficiencia humana tipo 2 en suero o plasma humano. Se controlaron los requisitos de calidad de los componentes de acuerdo a sus especificaciones. Se estudió la normalidad de valores de densidad óptica/valor límite y la homogeneidad de las medias y varianzas mediante las dócimas de Grubbs y Cochran. Se estimó la precisión en los controles positivo y negativo del sistema y en seis muestras con diferente reactividad al virus de inmunodeficiencia humana tipo 2 mediante el cálculo del coeficiente de variación y se confeccionaron las cartas de control de los valores de las medias de densidad óptica respecto al tiempo. Resultados: los requisitos de calidad de cada componente se cumplieron durante 12 meses, excepto las características funcionales del conjugado a partir de los seis meses. Los valores en las dócimas de Grubbs y Cochran fueron menores que los valores críticos tabulados para α del 1 y 5 por ciento por lo que existió homogeneidad en las medias y las varianzas en todo el periodo. El coeficiente de variación se mantuvo inferior al 10 por ciento excepto en las muestras con reactividad media y baja, mientras que en las cartas de control, los valores de densidad óptica se mantuvieron en el límite de la media ±2 desviaciones estándar hasta el noveno mes(AU)
Assuntos
Humanos , Técnicas Imunoenzimáticas/métodos , Reatividade-Estabilidade , Ensaio de Imunoadsorção Enzimática/métodos , HIV-2/imunologiaRESUMO
INTRODUCTION: The HIV-2 glycoprotein 36 (gp36) is often used in ELISA. An evaluation of the diagnostic indexes of antigen mixtures with a synthetic peptide of HIV2 gp36 (5) is performed in this study. METHODS: Five mixtures of gp36 (5) and the recombinant proteins of HIV1/2 were prepared. A total of 1306 samples were evaluated with UMELISA HIV1+2 RECOMBINANT used as reference. RESULTS: The variant (V-1) showed very good agreement as regards the reference method. CONCLUSION: The V-1 variant was shown to be highly effective in the immunodiagnosis of HIV 1/2.
Assuntos
Sorodiagnóstico da AIDS/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Antígenos HIV/imunologia , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Especificidade de Anticorpos , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/imunologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , Humanos , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/imunologia , Valor Preditivo dos Testes , Proteínas Recombinantes/síntese química , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Produtos do Gene env do Vírus da Imunodeficiência Humana/síntese químicaRESUMO
The identification of recent HIV infection is important for epidemiological studies and to monitor the epidemic. The objective of this study was to evaluate two rapid tests that are easily available to the Brazilian scientific community for using as markers of recent HIV infection. The Rapid Test - HIV-1/2 Bio-Manguinhos (Bio-Manguinhos/Fiocruz, Brazil) and the Rapid Check HIV 1&2 (NDI-UFES, Center for Infectious Diseases, Universidade Federal do Espírito Santo) were tested, using 489 samples with HIV positive serology, from blood donors, previously classified as recent or long-term infection by serological testing algorithm for recent HIV seroconversion (STARHS) or LS-HIV Vitros assay methods. The samples were diluted prior to testing (1:50 and 1:100 for the Rapid Test - HIV-1/2 Bio-Manguinhos, and 1:500 and 1:600 for the Rapid Check HIV 1&2). Negative samples were considered recent infection, whereas those showing any color intensity were associated with long-term infection. The best dilutions were 1:100 for HIV-1/2 Bio-Manguinhos test (Kappa = 0.840; overall agreement = 0.93), and 1:500 for the Rapid Check HIV 1&2 (Kappa = 0.867; overall agreement = 0.94). The results suggest that both rapid tests can be used to detect recent seroconversion.
Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Kit de Reagentes para Diagnóstico , Brasil , Soropositividade para HIV , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
This study is the first Biological and Behavioral Surveillance Survey to be conducted among personnel in the Belize Defense Force. The purpose of the study was to understand the prevalence of HIV infection and risk behaviours, and to identify key correlates of sexual risk behaviours. A representative sample of personnel underwent serological testing and an Audio Computer-Assisted Self Interview. Of those sampled, 351 completed a blood test and 334 completed a behavioural interview. The prevalence of HIV was 1.14%. Twelve percent had ever reported being diagnosed with a sexually transmitted infection (STI) or screened positive for HIV infection. The odds of ever having an STI/HIV were higher among those who had less education, those who had sex with a commercial sex worker (CSW), those who ever engaged in receptive anal sex and those with post-traumatic stress disorder (PTSD). Alcohol abuse and PTSD were prevalent and associated with HIV risk behaviours. These results are being used to inform current prevention efforts.
Assuntos
Preservativos/estatística & dados numéricos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Militares , Assunção de Riscos , Comportamento Sexual/estatística & dados numéricos , Adulto , Belize/epidemiologia , Feminino , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Humanos , Imunoensaio , Masculino , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Direct smear examination with Ziehl-Neelsen (ZN) staining for the diagnosis of pulmonary tuberculosis (PTB) is cheap and easy to use, but its low sensitivity is a major drawback, particularly in HIV seropositive patients. As such, new tools for laboratory diagnosis are urgently needed to improve the case detection rate, especially in regions with a high prevalence of TB and HIV. OBJECTIVE: To evaluate the performance of two in house PCR (Polymerase Chain Reaction): PCR dot-blot methodology (PCR dot-blot) and PCR agarose gel electrophoresis (PCR-AG) for the diagnosis of Pulmonary Tuberculosis (PTB) in HIV seropositive and HIV seronegative patients. METHODS: A prospective study was conducted (from May 2003 to May 2004) in a TB/HIV reference hospital. Sputum specimens from 277 PTB suspects were tested by Acid Fast Bacilli (AFB) smear, Culture and in house PCR assays (PCR dot-blot and PCR-AG) and their performances evaluated. Positive cultures combined with the definition of clinical pulmonary TB were employed as the gold standard. RESULTS: The overall prevalence of PTB was 46% (128/277); in HIV+, prevalence was 54.0% (40/74). The sensitivity and specificity of PCR dot-blot were 74% (CI 95%; 66.1%-81.2%) and 85% (CI 95%; 78.8%-90.3%); and of PCR-AG were 43% (CI 95%; 34.5%-51.6%) and 76% (CI 95%; 69.2%-82.8%), respectively. For HIV seropositive and HIV seronegative samples, sensitivities of PCR dot-blot (72% vs 75%; p=0.46) and PCR-AG (42% vs 43%; p=0.54) were similar. Among HIV seronegative patients and PTB suspects, ROC analysis presented the following values for the AFB smear (0.837), Culture (0.926), PCR dot-blot (0.801) and PCR-AG (0.599). In HIV seropositive patients, these area values were (0.713), (0.900), (0.789) and (0.595), respectively. CONCLUSION: Results of this study demonstrate that the in house PCR dot blot may be an improvement for ruling out PTB diagnosis in PTB suspects assisted at hospitals with a high prevalence of TB/HIV.
Assuntos
Infecções por HIV/epidemiologia , Reação em Cadeia da Polimerase/métodos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Comorbidade , DNA Bacteriano/genética , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Humanos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Prevalência , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Rapid, simple, low-cost, sensitive, and specific tests are needed to detect antibodies to all HIV-1 subtypes, especially in developing countries. OBJECTIVE: To evaluate the performance of a rapid diagnostic test for detection of HIV-1/2 antibodies in oral fluids and sera/plasma from subjects from geographic areas infected with different HIV-1 variants. STUDY DESIGN: OraQuick Rapid HIV-1/2 Diagnostic Test was evaluated in sera and oral fluids from 100 subjects from Spain and South-America. It was also assessed in 56 plasma and 39 oral fluid specimens from 56 Africans carrying HIV-1 non-B subtypes or inter-subtype recombinants defined by phylogenetic analysis at pol and gp41 coding regions. All patients were previously diagnosed as HIV-1 positive by serological tests (Abbott AxSYM HIV-1/2; Western Blot HIV-1/HIV-2 and Pepti-LAV, BIO-RAD). RESULTS: OraQuick provided positive results in all 156 serum/plasma specimens regardless of the infecting HIV-1 subtype, and in 136/139 (97.8%) oral fluids. The three oral specimens (2.2%) that yielded false-negative results by OraQuick were taken from one subtype B-infected Spaniard and from two subtype D-infected Africans. The last two were also negative by Pepti-LAV using plasma samples. Ten additional sera and 32 oral fluids from HIV-negative individuals yielded negative results by OraQuick. This rapid test showed good sensitivity for detecting anti-HIV-1 antibodies in oral fluids and in serum/plasma specimens from subjects carrying different HIV-1 subtypes and recombinant variants. CONCLUSION: OraQuick demonstrated its utility for detecting infections due to HIV-1 subtypes and recombinants common in developing countries.
Assuntos
Sangue/imunologia , Anticorpos Anti-HIV/análise , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/classificação , Escarro/imunologia , África , Reações Falso-Negativas , Feminino , HIV-1/imunologia , HIV-2/imunologia , Humanos , Masculino , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , América do Sul , EspanhaRESUMO
Human Immunodeficiency Virus Type 1 and 2 antibodies detection was performed in 457 dried whole blood spots samples (S&S 903). Q-Preven HIV 1+2 was the screening test used. The results were compared with the gold standard serum tests by ELISA (Cobas Core e Axsym HIV1/2 gO) and immunofluorescence was the definitive confirmatory test. The samples were obtained from the Hospital Nossa Senhora da Conceição in Porto Alegre, RS - Brazil, through whole blood transfer to filter paper card and sent to Caxias do Sul, RS-Brazil where the tests were performed. The dried whole blood spot stability was evaluated with two different panels. The first one was composed of five negative and five positive samples stored at room temperature, 4 degrees C, -20 degrees C and -70 degrees C, while the second was composed of two negative and three positive samples stored at 37 degrees C (humidity <50%). Each sample was screened every week for six weeks. These measurement results didn't show variation during the study period. The detected sensibility was 100%, specificity was 99.6%, the positive predictive value was 99.5% and negative predictive values were 100%. The results demonstrated high performance characteristics, opening a new perspective of dried whole blood spot utilization in HIV screening diagnosis.
Assuntos
Coleta de Amostras Sanguíneas/métodos , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Adolescente , Adulto , Idoso , Coleta de Amostras Sanguíneas/instrumentação , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Filtração , Técnica Indireta de Fluorescência para Anticorpo , Infecções por HIV/virologia , Humanos , Lactente , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
The aim of this study was to evaluate the performance of the rapid antibody test Determine HIV-1/2, in pregnant women at Tijuana General Hospital. Pregnant women seeking prenatal care or admitted in labour had blood drawn for a rapid HIV test (Determine HIV-1/2), enzyme immunoassay (EIA) and Western blot. Between March and November 2003, 1068 women in labour and 1529 women in prenatal care were enrolled. The sensitivity, specificity, positive and negative predictive values were 100%, 99.8%, 77% and 100%, respectively. For women in labour, the mean time between blood collection and rapid test results was 92 minutes (range: 20-205 minutes) compared with 41 hours (range 24-120 hours) for HIV EIA (P = 0.012). All HIV-exposed infants received oral zidovudine. These findings indicate that the rapid test Determine HIV-1/2 has a high sensitivity and specificity in pregnant women. Rapid HIV testing greatly diminishes the time to diagnosis and enables prompt intervention with antiretrovirals at delivery.
Assuntos
Sorodiagnóstico da AIDS , Anticorpos Anti-HIV/sangue , Infecções por HIV/diagnóstico , HIV-1/imunologia , HIV-2/imunologia , Doenças do Prematuro/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Feminino , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/virologia , Transmissão Vertical de Doenças Infecciosas , México , Valor Preditivo dos Testes , Gravidez , Complicações Infecciosas na Gravidez/virologia , Sensibilidade e Especificidade , Fatores de TempoRESUMO
BACKGROUND: Blood donor HIV antibody detection has been mandatory in Argentina since 1991, and p24 antigen screening was recommended in 1997. METHODS: A total of 30,132 consecutive donations were screened. Repeatedly reactive samples were tested by another screening test and/or by Western blot (WB) for HIV Ab, or by a neutralization assay for p24 Ag. RESULTS: Among the total, 0.3623% of samples were repeatedly reactive and 0.2084% were true HIV-infected donors. Only one donor tested nonreactive for HIV Ab, repeatedly reactive for p24 Ag, positive by neutralization assay, and seroconverted later. Samples with a signal-to-cutoff (S/CO) ratio >/= 3.00 on routine HIV Ab testing were 100.0% positive by WB and/or repeatedly reactive by the second test. In samples with a S/CO ratio < 3.00, 11.1% were positive by WB and/or the majority were nonreactive by the second test. Among HIV-infected donors, 89.5% possessed risk factors (which had been denied previously), 56.5% were repeatedly reactive by other screening procedures and 88.6% were coinfected with other blood-transmissible viruses. CONCLUSIONS: When the EIA S/CO ratio is >/= 3.00, WB can be replaced by a second screening test. The pre-donation questionnaire should be improved to detect risk behavior in prospective donors. There was a high association between HIV and other blood-transmissible viruses.