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1.
J Vasc Access ; 6(1): 9-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16552676

RESUMO

PURPOSE: To test whether an electromagnetic guidance system such as CathTrack would allow long-term central venous access devices to be reliably placed at a decreased cost and without radiation exposure to patients and staff. The following study was undertaken to verify accuracy of the CathTrack system for catheter placement and to develop guidelines for its use. METHODS: Twenty-nine consecutive patients were prospectively enrolled in the study and taken to the operating room for implantation of a permanent central venous access port. By protocol, the CathTrack system was used to guide initial catheter positioning using the center of the third intercostal space along the right sternal border as the desired external target. Fluoroscopy was then used to visualize tip position and relocate the catheter tip to the exact position desired by the surgeon. RESULTS: Catheter placement using the CathTrack system was successfully accomplished in 27 out of 29 patients. In two instances CathTrack was abandoned and fluoroscopy utilized because of difficulty in threading the initial guidewire into the superior vena cava. CONCLUSION: The CathTrack electromagnetic locator system can be used to reliably position catheters for the establishment of long-term central venous access. Decreased cost and elimination of radiation exposure are distinct advantages of this system over fluoroscopy.

2.
Lancet ; 362(9396): 1625-7, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14630444

RESUMO

Cheaper, simpler alternatives to CD4 lymphocyte count and HIV-1 RNA detection for assessing the prognosis of HIV-1 infection are needed for resource-poor settings. However, little is known about the predictive value of alternative assays, in particular in children. We assessed the prognostic value of total lymphocyte count, immune complex-dissociated p24 antigen, white blood cell count, packed-cell volume (haematocrit), and serum albumin for mortality in 376 HIV-1-infected, mainly African-American or Hispanic children enrolled during March, 1988 to January, 1991. In a Cox proportional hazards model, including all assay-alternatives to CD4 and RNA, total lymphocyte count (p<0.0001) and serum albumin (p=0.0107) independently predicted mortality. Further assessment of these markers is warranted in resource-poor settings.


Assuntos
Biomarcadores/sangue , Infecções por HIV/sangue , Infecções por HIV/mortalidade , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Feminino , Proteína do Núcleo p24 do HIV/sangue , HIV-1 , Hematócrito , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Modelos de Riscos Proporcionais , RNA Viral/sangue , Carga Viral
3.
Pediatr Infect Dis J ; 19(6): 544-51, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10877171

RESUMO

BACKGROUND: The sensitivity, specificity and positive predictive value of baseline serum concentrations of HIV-1 immune complex-dissociated (ICD) p24 antigen for predicting disease progression and mortality were assessed and compared with results obtained for HIV-1 ICD p24 antigen with HIV-1 p24 antibody and for HIV-1 RNA with CD4+ lymphocyte percent. METHODS: Data from HIV-infected children enrolled in a North American clinical trial (National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial) were analyzed. Disease progression was defined as growth failure, CD4+ lymphocyte percent decline to <15% after study entry or development of an AIDS-defining opportunistic infection. RESULTS: Baseline samples were available for ICD p24 antigen testing (median concentration, 319 pg/ml; range, <50 to 15,640) in 240 children. The combination of detectable ICD p24 antigen and low p24 antibody was more sensitive but less specific than the combination of high HIV-1 RNA and low CD4+ lymphocyte percent in predicting disease progression and mortality. Using receiver operating characteristic curves, the specificity of ICD p24 antigen with p24 antibody for classifying children's disease progression or mortality was as great as, or greater than, HIV-1 RNA with CD4+ lymphocyte percent at points on the curve corresponding to higher sensitivity. CONCLUSIONS: The use of ICD p24 antigen with p24 antibody to identify children at high risk of disease progression or mortality could be a viable alternative to the more expensive and technically difficult HIV-1 RNA and CD4+ lymphocyte assays in resource-poor settings, including developing countries where the majority of children with HIV-1 infection reside.


Assuntos
Contagem de Linfócito CD4 , Anticorpos Anti-HIV/análise , Proteína do Núcleo p24 do HIV/análise , HIV-1/imunologia , RNA Viral/análise , Criança , Pré-Escolar , Método Duplo-Cego , Proteína do Núcleo p24 do HIV/imunologia , HIV-1/genética , Humanos , Lactente , Prognóstico , Sensibilidade e Especificidade
4.
AIDS ; 13(1): 31-9, 1999 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-10207542

RESUMO

OBJECTIVE: The role of HIV-1 antibody in modulating disease progression must be assessed in the context of other immune and viral load markers. We evaluated the association between HIV-1 p24 antibody, HIV-1 RNA, immune complex-dissociated (ICD) p24 antigen, CD4 cell percentage, and mortality in a cohort of 218 HIV-infected children enrolled in a trial of intravenous immunoglobulin prophylaxis of bacterial infections. METHODS: CD4 cell percentage was measured and sera collected and stored at baseline and every 3 months on study (1988-1991). Stored sera were assayed for HIV-1 p24 antibody, HIV-1 RNA, and ICD p24 antigen. Mortality was recorded during the trial and updated through 1996 (mean total follow-up, 6.3 years). RESULTS: Eighty-one (37%) children died; probability of mortality for children with baseline HIV-1 p24 antibody concentrations of undetectable (< 1), 1-4, 5-124, and > or = 125 reciprocal titer units (RTU) was 61, 50, 24, and 10%, respectively. A 3.5-fold increase in the relative risk (RR) of death [95% confidence interval (CI), 2.2-5.5] was observed among children with baseline HIV-1 p24 antibody concentration < 5 RTU compared with > or = 5 RTU. In multivariate analyses, p24 antibody, HIV-1 RNA, and CD4 cell percentage but not ICD p24 antigen were independently associated with mortality; the RR of death increased by 1.7 (95% CI, 1.3-2.1) for each log10 decrement in baseline HIV-1 p24 antibody. CONCLUSIONS: HIV-1 p24 antibody, HIV-1 RNA and CD4 cell percentage independently predict mortality amongst infected children. Whereas CD4 cell percentage provides an estimate of the general degree of immune suppression, HIV-1 p24 antibody could provide an easily obtained, inexpensive assessment of CD4 cell function and could augment prognostic information provided by CD4 cell count and viral load for clinical management of infected children.


Assuntos
Anticorpos Anti-HIV/imunologia , Proteína do Núcleo p24 do HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/mortalidade , HIV-1/imunologia , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Dosagem de Genes , Anticorpos Anti-HIV/sangue , Infecções por HIV/sangue , Infecções por HIV/virologia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , RNA Viral , Fatores de Risco
5.
J Infect Dis ; 179(3): 567-75, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9952362

RESUMO

Pediatric AIDS Clinical Trials Group protocol 185 evaluated whether zidovudine combined with human immunodeficiency virus (HIV) hyperimmune immunoglobulin (HIVIG) infusions administered monthly during pregnancy and to the neonate at birth would significantly lower perinatal HIV transmission compared with treatment with zidovudine and intravenous immunoglobulin (IVIG) without HIV antibody. Subjects had baseline CD4 cell counts /=200/microL) but not with time of zidovudine initiation (5.6% vs. 4.8% if started before vs. during pregnancy; P=. 75). The Kaplan-Meier transmission rate for HIVIG recipients was 4. 1% (95% confidence interval, 1.5%-6.7%) and for IVIG recipients was 6.0% (2.8%-9.1%) (P=.36). The unexpectedly low transmission confirmed that zidovudine prophylaxis is highly effective, even for women with advanced HIV disease and prior zidovudine therapy, although it limited the study's ability to address whether passive immunization diminishes perinatal transmission.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Imunoglobulinas Intravenosas/uso terapêutico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez , Zidovudina/uso terapêutico , Adulto , Peso ao Nascer , Cesárea , Parto Obstétrico , Feminino , Idade Gestacional , Infecções por HIV/terapia , Infecções por HIV/transmissão , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Resultado da Gravidez , Porto Rico , Estados Unidos
6.
Pediatr Infect Dis J ; 18(2): 134-42, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10048685

RESUMO

BACKGROUND: Vitamin A deficiency is associated with increased risks of vertical transmission of HIV-1 (HIV) and of disease progression and mortality among HIV-infected adults. The objectives of the study were to describe serum vitamin A concentrations among HIV-infected children in the National Institute of Child Health and Human Development IVIG Clinical Trial, to examine changes in vitamin A concentrations and to investigate the relationships between vitamin A concentrations and morbidity and mortality. METHODS: Blood was collected from children at baseline and at 3-month intervals throughout the study. Serum samples were stored at -70 degrees C at a central repository until retrieved for vitamin A assay. Samples were hexane-extracted and assayed by high performance liquid chromatography. The rate of change in vitamin A concentrations, calculated by fitting a linear regression model, was expressed as micrograms/dl/year. RESULTS: The median vitamin A concentration at baseline (n = 207 children) was 31.0 microg/dl [range, undetectable (< 10 microg/dl) to 98 microg/dl]. The rate of change in vitamin A concentrations (n = 180 children) did not vary significantly by any factor other than baseline vitamin A concentration. Baseline vitamin A concentration was not associated with morbidity (incidence of infections, growth failure, CD4+ percent decline below 15%, increases in serum HIV RNA concentrations above either 10(5) or 10(6) copies/ml or acute care hospitalization). Neither baseline vitamin A concentration nor the rate of change of vitamin A concentrations was associated with mortality. CONCLUSIONS: Among these North American children with relatively normal vitamin A concentrations, vitamin A was not observed to be associated with morbidity or mortality.


Assuntos
Infecções por HIV/sangue , HIV-1 , Vitamina A/sangue , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Estudos de Coortes , Feminino , Infecções por HIV/mortalidade , Humanos , Lactente , Masculino , Morbidade , América do Norte/epidemiologia , Estudos Prospectivos , RNA Viral/sangue , Análise de Sobrevida
7.
Pediatr Infect Dis J ; 17(10): 872-80, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9802627

RESUMO

OBJECTIVE: To describe the epidemiologic, clinical, radiologic, laboratory and treatment characteristics of acute pneumonia and its association with mortality in HIV-infected children. METHODS: Data were collected during a trial of intravenous immunoglobulin (IVIG) for infection prophylaxis (1988 to 1991); CD4+ percentage was measured and HIV RNA was assessed on stored sera collected at baseline and every 3 months. Mortality was recorded during the trial and updated through 1996. All reported physician-diagnosed pneumonia episodes underwent blinded review for trial endpoint classification as acute (new radiologic findings and presence of clinical symptoms) or nonacute. RESULTS: On blinded clinical trial endpoint review of all reported pneumonia episodes (n = 281), only 47% were classified as acute. One hundred thirty-one episodes of acute pneumonia were reported in 93 children (47 in 31 IVIG and 84 in 62 placebo patients, P < 0.01). The incidence of acute pneumonia was 24 episodes per 100 patient years. Findings associated with an acute bacterial process were uncommon (leukocytosis > or =15000/mm3 in 21% and fever > or =103 degrees F in 32% of episodes). Multiple acute episodes occurred in 34% of the children and were associated with increased risk of mortality in a univariate analysis (risk ratio, 2.1; 95% confidence interval, 1.3 to 3.4, P = 0.002), but in a multivariate model only baseline HIV RNA copy number and CD4+ percentage remained independently associated with mortality (relative risk, 2.0 and 1.4, respectively, P < 0.001). CONCLUSION: Acute pneumonia was a common occurrence in HIV-infected children and was associated with long term mortality risk. Multiple episodes of acute pneumonia likely represent a marker of progressive disease and immunologic dysfunction rather than being causally associated with increased long term mortality.


Assuntos
Infecções por HIV/complicações , Pneumonia/complicações , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Doença Aguda , Anti-Infecciosos/uso terapêutico , Infecções Bacterianas/prevenção & controle , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Infecções por HIV/mortalidade , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Pneumonia/mortalidade , Fatores de Risco , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Carga Viral
9.
Transfusion ; 37(6): 634-40, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9191825

RESUMO

BACKGROUND: Calculations of the incidence of hepatitis B virus (HBV) infections in the blood donor setting that are based solely on data for seroconversion to hepatitis B surface antigen (HBsAg) will underestimate the incidence due to the transient nature of antigenemia. Estimates based on antibody to hepatitis B core antigen will overestimate the incidence due to false-positive results caused by the nonspecificity of the test. STUDY DESIGN AND METHODS: Serologic test results were obtained from multiple-time volunteer donors at five United States blood centers from January 1991 through December 1993. The observed HBsAg seroconversion rate was multiplied by an adjustment factor, derived from the weighted average probability of a positive HBsAg test for HBV-infected donors who become chronic carriers, for donors with a primary antibody response without detectable antigenemia, and for donors who develop transient antigenemia. RESULTS: Among 586,507 multiple-time donors giving 2,318,356 donations and observed for 822,426 person-years, the HBsAg incidence rate was 4.01 per 100,000 person-years. On the basis of prior reports of the duration of HBsAg positivity and the observed distribution of interdonation intervals among the study group, there was an estimated 53-percent chance that an HBV-infected donor with transient antigenemia would have a positive HBsAg test result. If 70 percent of newly HBV-infected adults have transient antigenemia, 25 percent have a primary antibody response without primary antigenemia, and 5 percent become chronic carriers, the overall chance of being detected by the HBsAg test was 42 percent, for an adjustment factor of 2.38. The total HBV incidence rate, therefore, was estimated to be 9.54 per 100,000 person-years. CONCLUSION: The crude HBV incidence rate observed from HBsAg test results will underestimate the true rate. The adjusted HBV incidence rate should be used in applications such as estimations of residual HBV risk to the blood supply and projections of the benefits of screening for HBV DNA.


Assuntos
Doadores de Sangue , Hepatite B/epidemiologia , Adulto , Doadores de Sangue/estatística & dados numéricos , DNA Viral/sangue , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Humanos , Incidência , Métodos
10.
J Infect Dis ; 175(5): 1029-38, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9129063

RESUMO

Association of human immunodeficiency virus type 1 (HIV-1) RNA level, CD4 cell percent, and mortality was examined in stored sera from 254 infected children in an intravenous immunoglobulin infection prophylaxis trial. Ninety-two children (36.2%) died (41 during the study, 51 during long-term follow-up). The geometric mean baseline HIV-1 RNA level was 104,626 copies/mL, and the mean CD4 cell percent was 25%. Relative risk of death (RR) was 2.1 if the baseline RNA level was >100,000 copies/mL (95% confidence interval [CI], 1.4-3.0) and was 3.0 if the baseline CD4 cell percent was <15% (95% CI, 2.2-4.0). If RNA levels increased after baseline, the RR was 1.8 (95% CI, 1.3-2.6), and if the CD4 cell percent dropped to <15%, the RR was 2.8 (95% CI, 1.6-4.9). In a multivariate model, both baseline RNA level and CD4 cell percent were independently associated with mortality risk. In a time-dependent model, the RR per log10 increase in HIV-1 RNA copy numbers was 2.8 (95% CI, 2.1-3.6) and per 5 percentage point decrement in CD4 cell percent was 1.3 (95% CI, 1.2-1.5). Both variables should be considered for in decision-making regarding therapy and evaluation of antiretroviral response.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , Contagem de Linfócito CD4 , HIV-1/isolamento & purificação , RNA Viral/sangue , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/terapia , Criança , Pré-Escolar , Estudos de Coortes , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Modelos Estatísticos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo
11.
Transfusion ; 37(2): 199-205, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9051096

RESUMO

BACKGROUND: Blood donors who test repeatably reactive on enzyme immunoassay (EIA) and are not confirmed as positive are a continuing problem for blood banks. Units are discarded and donors are deferred, in spite of multiple studies indicating that such donors are very rarely infected with the transmissible agents. Few data are available, however, with which to evaluate whether the discarded units are more likely to come from particular demographic subgroups. STUDY DESIGN AND METHODS: The Retrovirus Epidemiology Donor Study database of over 2 million allogeneic whole-blood donations collected in the years 1991 through 1993 was utilized. The prevalence of false-positive and indeterminate test results within demographic subgroups was computed for antibodies to human immunodeficiency virus, hepatitis C virus, and human T-lymphotropic virus (anti-HIV, anti-HCV, anti-HTLV, respectively) and hepatitis B surface antigen (false-positive only) as the proportion of donations that were repeatably reactive on EIA but negative or indeterminate on the confirmatory or supplemental test. RESULTS: Several demographic groups with increased prevalence of false-positive and indeterminate anti-HIV results were the same females, younger age groups, blacks, and first-time donors. Likewise, many of the demographic subgroups with increased prevalence of false-positive and indeterminate anti-HCV results were similar: older age groups, non-whites, lower education levels, first-time donors, donors making directed donations, and donors who had received transfusions. For anti-HTLV, by contrast, the oldest group had the highest prevalence of false-positive results but the lowest prevalence of indeterminate results: blacks had the lowest prevalence of false positive results but the highest prevalence of indeterminate results. CONCLUSION: If units that test repeatably reactive on EIA but that are not confirmed as positive are almost always from individuals not infected with the virus in question, then these results indicate that there may be sex-, race-, and/or age-linked proteins cross-reacting with the test kit materials. Elucidation of these antigenic determinates and their subsequent removal should be a priority.


Assuntos
Doadores de Sangue , Técnicas Imunoenzimáticas , Reações Falso-Positivas , Soroprevalência de HIV , Anticorpos Anti-Hepatite/sangue , Humanos , Técnicas Imunoenzimáticas/normas , Sensibilidade e Especificidade
12.
N Engl J Med ; 334(26): 1685-90, 1996 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-8637512

RESUMO

BACKGROUND: Accurate estimates of the risk of transfusion-transmitted infectious disease are essential for monitoring the safety of the blood supply and evaluating the potential effect of new screening tests. We estimated the risk of transmitting the human Immuno-deficiency virus (HIV), the human T-cell lymphotropic virus (HTLV), the hepatitis C virus (HCV), and the hepatitis B virus (HBV) from screened blood units donated during the window period following a recent, undetected infection. METHODS: Using data on 586,507 persons who each donated blood more than once between 1991 and 1993 at five blood centers (for a total of 2,318,356 allogeneic blood donations), we calculated the incidence rates of seroconversion among those whose donations passed all the screening tests used. We adjusted these rates for the estimated duration of the infectious window period for each virus. We then estimated the further reductions in risk that would result from the use of new and more sensitive viral-antigen or nucleic acid screening tests. RESULTS: Among donors whose units passed all screening tests, the risks of giving blood during an infectious window period were estimated as follows: for HIV, 1 in 493,000 (95 percent confidence interval, 202,000 to 2,778,000); for HTLV, 1 in 641,000 (256,000 to 2,000,000); for HCV, 1 in 103,000 (28,000 to 288,000); and for HBV, 1 in 63,000 (31,000 to 147,000). HBV and HCV accounted for 88 percent of the aggregate risk of 1 in 34,000. New screening tests that shorten the window periods for the four viruses should reduce the risks by 27 to 72 percent. CONCLUSIONS: The risk of transmitting HIV, HTLV, HCV, or HBV infection by the transfusion of screened blood is very small, and new screening tests will reduce the risk even further.


Assuntos
Reação Transfusional , Viroses/transmissão , Anticorpos Antivirais/sangue , Sangue/virologia , Doadores de Sangue , Infecções por Deltaretrovirus/diagnóstico , Infecções por Deltaretrovirus/epidemiologia , Infecções por Deltaretrovirus/transmissão , Transmissão de Doença Infecciosa , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Hepatite B/transmissão , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite C/transmissão , Humanos , Incidência , Risco , Testes Sorológicos , Viroses/diagnóstico , Viroses/epidemiologia
13.
Am J Obstet Gynecol ; 174(5): 1461-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-9065112

RESUMO

OBJECTIVE: Our objective was to examine changes in CD4+ and CD8+ cell levels during pregnancy and post partum and to determine whether they differ for human immunodeficiency virus-1-seropositive and seronegative women. STUDY DESIGN: A total of 192 human immunodeficiency virus-1-seropositive and 148 seronegative women enrolled in a study of mother-to-child transmission of human immunodeficiency virus-1 who had at least two lymphocyte subset measurements performed during pregnancy or post partum were included in this analysis. Mixed effects repeated-measures models were developed to examine changes in CD4+ and CD8+ cell levels during this period. RESULTS: Consistent with prior reports that CD4+ cell levels decline during pregnancy and return to normal post partum, percent levels increased between the third trimester and 12 months post partum among human immunodeficiency virus-seronegative women (1.98%, p = 0.04). However, CD4+ levels declined steadily during pregnancy and post partum among seropositive women (-1.57%, p = 0.02 between the third trimester and 12 months post partum; =2.65%, p = 0.0004 between 2 and 24 months post partum). The percent CD8+ cell levels increased at or near delivery and declined to baseline between 2 and 6 months post partum in both seronegative and seropositive women, although only the declines were statistically significant in both groups (-2.66%, p = 0.004; and -2.02%, p = 0.02, respectively). CONCLUSIONS: The percent CD4+ cell levels declined steadily during pregnancy and post partum among human immunodeficiency virus-seropositive women, indicating that human immunodeficiency virus disease continues to progress during this period. The percent CD8+ cell levels increased at or near delivery and declined to baseline post partum in both seronegative and seropositive women. These findings may have important clinical implications for both human immunodeficiency virus-infected and uninfected pregnant women.


Assuntos
Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos , Soropositividade para HIV/sangue , HIV-1/imunologia , Contagem de Linfócitos , Complicações Infecciosas na Gravidez/sangue , Infecção Puerperal/sangue , Adulto , Estudos Transversais , Feminino , Soronegatividade para HIV/imunologia , Humanos , Período Pós-Parto/sangue , Gravidez/sangue , Terceiro Trimestre da Gravidez/imunologia , Análise de Regressão
14.
Transfusion ; 36(3): 203-8, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8604502

RESUMO

BACKGROUND: There currently is debate on whether to include new assays for viral antigens and nucleic acids in the battery of screening tests applied to all blood donations. Proposals call for implementation of p24 antigen screening tests to help identify donors who are infected with human immunodeficiency virus type 1 (HIV-1) but have not yet seroconverted (window-period donors). There is concern, however, that people at higher risk for HIV infection will be attracted to blood centers in order to obtain the results of an HIV assay that is not routinely available elsewhere. Therefore, the benefit of antigen testing may be offset by an increase in the HIV incidence rate among blood donors. STUDY DESIGN AND METHODS: Estimates were obtained from previous reports for the HIV incidence rate among blood donors, the percentage of donations from test-seeking donors, the duration of the HIV-infectious window period, and the performance of p24 antigen screening assays. Sensitivity analyses were performed by using various percentages of test-seeking donors following implementation of antigen testing and various HIV incidence rate ratios of test-seekers to nonseekers. Hypothetical residual HIV risks were calculated for multiple scenarios and compared to the current estimate of HIV risk without antigen screening of blood donations. RESULTS: If antigen testing reduces the window period by 27 percent (e.g., from 22 days to 16 days), and the HIV incidence rate among test-seekers is 30 times that among nonseekers, then the benefit of antigen testing will be eliminated if the percentage of test-seekers (currently estimated at 3.2%) increases to 5.7 percent. If antigen testing reduces the window period by approximately 45 percent (e.g., from 22 days to 10 days or from 13 days to 6 days) and the HIV incidence rate ratio (test-seekers vs. nonseekers) is assumed to be equal to the HIV prevalence ratio (5.3), then the percentage of donations from test-seeking donors would have to increase to 25 percent of all donations to offset the benefit of antigen screening. CONCLUSION: This model helps identify the key measures for assessing the potential adverse effect of increased test seeking as a consequence of the addition of p24 antigen (or other direct virus) assays to blood donor screening programs. In most scenarios, the beneficial effect of antigen screening exceeded the potential detrimental effect of attracting higher-risk, test-seeking donors. The possibility cannot be ruled out, however, that a subgroup of high-risk, test-seeking donors attracted to the blood centers by a new HIV test will offset the reduction in the residual risk of HIV infection associated with antigen screening.


Assuntos
Sorodiagnóstico da AIDS , Síndrome da Imunodeficiência Adquirida/diagnóstico , Doadores de Sangue , Proteína do Núcleo p24 do HIV/sangue , HIV-1 , Síndrome da Imunodeficiência Adquirida/epidemiologia , HIV-1/imunologia , Humanos , Incidência , Fatores de Risco
15.
Transfusion ; 36(3): 232-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8604508

RESUMO

BACKGROUND: The value of the test for antibody to hepatitis B core antigen (anti-HBc) as a surrogate screening assay in the time before sensitive, virus-specific screening tests were available has been well established. There is significant debate, however about the residual value of anti-HBc screening after the implementation of human immunodeficiency virus (HIV)-, human T-lymphotrophic virus (HTLV)-, and hepatitis C virus (HCV)-specific assays and, in particular, about its utility as a lifestyle marker to identify persons at risk for retrovirus infections. STUDY DESIGN AND METHODS: Screening tests for antibodies to HIV, HTLV, and HBc, as well as confirmatory or supplemental test results for anti-HIV and anti-HTLV, were obtained from approximately 2.8 million donations collected from 1991 through 1993 by five blood centers within the United States. The sensitivity, positive predictive value, and relative prevalence of anti-HBc for each retrovirus were calculated and compared among demographic subgroups. RESULTS: The overall relationship between anti-HBc and anti-HIV was similar to that between anti-HBc and anti-HTLV. When calculated from the measured endpoint of the prevalence of anti-HIV-positive and anti-HTLV-positive donations, the sensitivities were 31.1 and 26.2 percent, the positive predictive values were 0.18 and 0.21 percent, and the relative prevalences were 30.1 and 23.8, respectively. Among 27 anti-HIV-seroconverting donors and 9 anti-HTLV-seroconverting donors, the sensitivities were 7.4 percent (95% CI: 0.9-24.3%) and 0 percent (95% CI: 0.0-28.3%), respectively. It was estimated that for each HIV-infected window-period donation detected by anti-HBc, from 19,000 to 81,000 HIV-noninfected donations are discarded. Similarly, more than 33,000 HTLV-noninfected donations are likely to be discarded for each HTLV-infected donation detected by anti-HBc. CONCLUSION: Although anti-HBc-reactive donations are more likely to be seropositive for a retrovirus than are anti-HBc-nonreactive donations, the low positive predictive value limits the test's effectiveness. If the anti-HBc test is retained in the blood donor setting, efforts should be focused on reducing the number of false-positive results.


Assuntos
Doadores de Sangue , Infecções por Deltaretrovirus/diagnóstico , Infecções por HIV/diagnóstico , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Adolescente , Adulto , Feminino , Soronegatividade para HIV , Soropositividade para HIV , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
16.
Clin Infect Dis ; 21(5): 1175-81, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8589139

RESUMO

The clinical presentation, radiological and laboratory evaluation, treatment, and risk factors of sinusitis in a cohort of 376 human immunodeficiency virus (HIV)-infected children from a placebo-controlled clinical trial of intravenous immunoglobulin (IVIG) as prophylaxis for infections were examined. Ninety-five episodes of sinusitis were described in 60 patients; one-third of the patients had two or more episodes. Sinusitis episodes were commonly associated with nonspecific, chronic symptoms (67.4%, persistent nasal discharge; 54.7%, nocturnal or persistent cough), whereas symptoms more specific to acute sinusitis were less frequent (17.9%, headache or facial pain; 9.5%, periorbital swelling; 25.3%, temperature of > or = 102 degrees F; 9%, total white blood cell count of > or = 15,000/mm3). The sinuses primarily involved were the maxillary sinus (85.9%) and the ethmoidal sinus (42.3%); 36% of episodes involved two or more sinuses. Preceding respiratory infections did not appear to increase the risk of sinusitis, and CD4+ lymphocyte counts in children with and without sinusitis did not differ. Neither monthly IVIG prophylaxis nor three times weekly trimethoprimsulfamethoxazole prophylaxis for Pneumocystis carinii pneumonia decreased the risk of sinusitis. Sinusitis in HIV-infected children is most often subacute and recurrent. Evaluations of new modalities for prophylaxis for sinusitis are needed.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Sinusite/complicações , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Anti-Infecciosos/farmacologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Imunoglobulinas Intravenosas/farmacologia , Lactente , Masculino , Recidiva , Fatores de Risco , Sinusite/diagnóstico , Sinusite/prevenção & controle , Combinação Trimetoprima e Sulfametoxazol/farmacologia
17.
Transfusion ; 35(11): 903-10, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8604486

RESUMO

BACKGROUND: Since the mid-1980s, blood banks in the United States have screened donors for elevated alanine aminotransferase (ALT) in an effort to prevent posttransfusion hepatitis. The present study was designed to quantitate the residual value of ALT screening following the implementation of hepatitis C virus (HCV) assays. STUDY DESIGN AND METHODS: Two approaches were used. First, a database of 2.3 million donations made by 586,507 volunteer blood donors between 1991 and 1993 was used to compare the incidence of seroconversion to hepatitis B virus (HBV) and HCV marker positivity in donors with elevated ALT values and with normal ALT values. Second, the duration of ALT elevation prior to HBV and HCV seroconversion was determined from 34 well-documented cases of posttransfusion HBV and HCV; elevated-ALT window periods were multiplied by rates of HBV and HCV incidence in donors to project the yield of ALT screening. Predictive value and cost-effectiveness analyses were also performed to compare the value of ALT screening before and after HCV screening was implemented. RESULTS: Both approaches indicate that ALT testing does not detect HBV in the window phase but does currently identify approximately 3 HCV window-phase donations per 1 million donations; this contrasts with ALT detection of approximately 1800 HCV-infectious units per 1 million donations prior to anti-HCV screening. Currently, only 8 in 10,000 donated units with elevated ALT (negative anti-HCV) are infected with HCV. The cost of continued ALT screening was estimated at $7,931,000 per quality-adjusted year of life saved. CONCLUSION: The yield, predictive value, and cost-effectiveness of ALT screening of blood donors have declined dramatically with the implementation of progressively improved anti-HCV assays. ALT screening of volunteer blood donors should be discontinued.


Assuntos
Alanina Transaminase/sangue , Doadores de Sangue , Hepatite B/prevenção & controle , Hepatite C/prevenção & controle , Reação Transfusional , Análise Custo-Benefício , Humanos
18.
Transfusion ; 34(10): 870-6, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7940658

RESUMO

BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a "random process," as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.


Assuntos
Doadores de Sangue , Transfusão de Sangue/psicologia , Confidencialidade , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por Retroviridae/transmissão , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Infecções por Retroviridae/epidemiologia , Sensibilidade e Especificidade
19.
Pediatr Infect Dis J ; 13(6): 477-84, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8078734

RESUMO

After completion of a placebo-controlled trial of intravenous immunoglobulin (IVIG) infection prophylaxis, patients were offered open label IVIG and optional participation in a follow-up study. The purpose of the follow-up study was to evaluate the IVIG effect in original placebo recipients and longevity of IVIG benefit in original IVIG recipients. Of 212 human immunodeficiency virus-infected children on study at trial closure, 148 (67 of 98 (68%) placebo and 81 of 114 (71%) IVIG patients) received open label IVIG for a mean of 16 months. When open label IVIG was begun, 45% were receiving trimethoprim-sulfamethoxazole prophylaxis for Pneumocystis carinii pneumonia (43% of placebo and 47% of IVIG patients) and 54% were receiving zidovudine (55% of placebo and 53% of IVIG patients). In patients who received placebo during the original study, the rate of serious bacterial infections was significantly lower after change to open label IVIG (estimated 15.8 fewer episodes/100 patient years; 95% confidence interval, 3.2 to 28.5; P = 0.014). Similar findings were observed for minor bacterial infections (estimated 61.2 fewer/100 patient years; 95% confidence interval, 29.2 to 93.3; P < 0.001) and hospitalizations (estimated 43.7 fewer/100 patient years; 95% confidence interval, 27.7 to 59.6; P < 0.001). Decreases were observed whether or not trimethoprim-sulfamethoxazole prophylaxis was being given at the time open label IVIG was begun. In patients who received IVIG during the original study, no significant difference was seen in infections or hospitalizations after change to open label IVIG.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Infecções Bacterianas/prevenção & controle , Imunoglobulinas Intravenosas/uso terapêutico , Pneumonia por Pneumocystis/prevenção & controle , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Seguimentos , Infecções por HIV/terapia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pneumonia por Pneumocystis/tratamento farmacológico , Fatores de Tempo , Resultado do Tratamento , Zidovudina/uso terapêutico
20.
Am J Health Promot ; 8(2): 117-23, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-10146826

RESUMO

PURPOSE: The purpose of this report is to provide general information on the personal characteristics, health status, and health interests reported by long-haul truck drivers. DESIGN: A cross-sectional survey was conducted based on a convenience sample. Statistical independence between comparison groups for driver type, age, and gender were tested with the Pearson chi-square test. SETTING: The study population consisted of truck drivers who stopped at one of 65 truck stops participating in a trucker trade show. SUBJECTS: Subjects were 2,945 male self-identified truck drivers and 353 female self-identified truck drivers who visited health booths at the trade show. It was estimated that two thirds of visitors to the health booth participated. MEASURES: A self-administered, close-ended questionnaire recorded the participant's personal characteristics, health status, and health interests. Blood pressure was measured by trained volunteers. RESULTS: A large percentage of male truck drivers smoked cigarettes (54% vs. 30% of U.S. white males), did not exercise regularly (92%), were overweight (50% vs. 25% of U.S. white males), and/or were not aware they had high blood pressure (66% vs. 46% of U.S. population). Also, 23% of surveyed truck drivers tested positive on one measure of alcoholism. CONCLUSIONS: Although a scientific sample frame was not used, the health status and lifestyle observed in this study suggest truck drivers would clearly benefit from a health education and promotion program. The truck stops should be evaluated as a possible setting for such a program.


Assuntos
Condução de Veículo , Comportamentos Relacionados com a Saúde , Adolescente , Adulto , Idoso , Pressão Sanguínea , Demografia , Feminino , Promoção da Saúde , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Ocupacional , Fatores de Risco , Inquéritos e Questionários
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