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1.

Background

Because a recent cluster of false positive results on the OraQuick ADVANCE® Rapid HIV-1/2 Antibody Test occurred in San Francisco on test kits close to their expiration date, we decided to assess the relationship between time to expiration and rate of false positive results from tests used with oral fluid.

Methodology/Principal Findings

We analyzed results of 20,904 tests with either an initial HIV-negative result (n = 20,828) or a preliminary positive result that was then negative on confirmatory tests (n = 76). We computed specificity for kits with time to expiration from ≤1 to ≥6 months, with exact binomial confidence intervals, then used logistic regression to estimate the independent association of time to expiration with false positive results, adjusting for site and technician effects. For 1,108 kits used in the last month before expiration, specificity was 98.83% (95% exact binomial confidence interval (CI) 98.00%–99.37%); the upper bound is below the claimed specificity of 99.60%. After adjustment using regression standardization for the effects of site, test lot, and technician factors, adjusted specificity in the last month before expiration was 99.18% (95% bootstrap confidence interval 98.60–99.57%).

Conclusions/Significance

We found that specificity of the OraQuick ADVANCE® with oral fluid declined significantly with ≤1 month remaining to expiration, leaving little margin for error from other sources.  相似文献   

2.

Background

It remains controversial how HCV coinfection influences the disease progression during HIV-1 infection. This study aims to define the influence of HCV infection on the replication of HIV-1 and the disease progression in HIV-infected former plasma donors (FPDs) naïve to ART.

Methodology/Principal Findings

168 HIV-1-infected FPDs were enrolled into a cohort study from Anhui province in central China, and thereafter monitored at month 3, 9, 15, 21 and 33. Fresh whole blood samples were used for CD4+ T-cell counting. Their plasma samples were collected and stored for quantification of HIV-1 viral loads and for determination of HCV and Toxoplasma. Out of 168 HIV-infected FBDs, 11.9% (20 cases), 80.4% (135 cases) and 7.7% (13 cases) were infected with HIV-1 alone, HIV-1/HCV and HIV/HCV/Toxoplasma, respectively. During the 33-month follow-up, only 35% (7 out of 20 cases) HIV-1 mono-infected subjects remained their CD4+ T-cell counts above 200 cells/µl and retained on the cohort study, which was significantly lower than 56% (75 out of 135 cases) for HIV/HCV group and 69% (9 out of 13 cases) for HIV/HCV/Toxoplasma group (p<0.05). CD4+ T cells in HIV mono infection group were consistently lower than that in HIV/HCV group (p = 0.04, 0.18, 0.03 and 0.04 for baseline, month 9, month 21 and month 33 visit, respectively). In accordance with those observations, HIV viral loads in HIV mono-infection group were consistently higher than that in HIV/HCV group though statistical significances were only reached at baseline (p = 0.04).

Conclusions/Significance

These data indicated HCV coinfection with HIV-1 is associated with the slower disease progression at the very late stage when comparing with HIV-1 mono-infection. The coinfection of Toxoplasma with HIV and HCV did not exert additional influence on the disease progression. It will be highly interesting to further explore the underlying mechanism for this observation in the future.  相似文献   

3.

Background

Recent reports suggest that Natural Killer (NK) cells may modulate pathogenesis of primary HIV-1 infection. However, HIV dysregulates NK-cell responses. We dissected this bi-directional relationship to understand how HIV impacts NK-cell responses during primary HIV-1 infection.

Methodology/Principal Findings

Paired samples from 41 high-risk, initially HIV-uninfected CAPRISA004 participants were analysed prior to HIV acquisition, and during viraemic primary HIV-1 infection. At the time of sampling post-infection five women were seronegative, 11 women were serodiscordant, and 25 women were seropositive by HIV-1 rapid immunoassay. Flow cytometry was used to measure NK and T-cell activation, NK-cell receptor expression, cytotoxic and cytokine-secretory functions, and trafficking marker expression (CCR7, α4β7). Non-parametric statistical tests were used. Both NK cells and T-cells were significantly activated following HIV acquisition (p = 0.03 and p<0.0001, respectively), but correlation between NK-cell and T-cell activation was uncoupled following infection (pre-infection r = 0.68;p<0.0001; post-infection, during primary infection r = 0.074;p = 0.09). Nonetheless, during primary infection NK-cell and T-cell activation correlated with HIV viral load (r = 0.32''p = 0.04 and r = 0.35;p = 0.02, respectively). The frequency of Killer Immunoglobulin-like Receptor-expressing (KIRpos) NK cells increased following HIV acquisition (p = 0.006), and KIRpos NK cells were less activated than KIRneg NK cells amongst individuals sampled while seronegative or serodiscordant (p = 0.001;p<0.0001 respectively). During HIV-1 infection, cytotoxic NK cell responses evaluated after IL-2 stimulation alone, or after co-culture with 721 cells, were impaired (p = 0.006 and p = 0.002, respectively). However, NK-cell IFN-y secretory function was not significantly altered. The frequency of CCR7+ NK cells was elevated during primary infection, particularly at early time-points (p<0.0001).

Conclusions/Significance

Analyses of immune cells before and after HIV infection revealed an increase in both NK-cell activation and KIR expression, but reduced cytotoxicity during acute infection. The increase in frequency of NK cells able to traffic to lymph nodes following HIV infection suggests that these cells may play a role in events in secondary lymphoid tissue.  相似文献   

4.

Background

Placental cytokines play crucial roles in the establishment and maintenance of pregnancy as well as protecting the foetus from infections. Previous studies have suggested the implication of infections such as P. falciparum and HIV in the stimulation of placental cytokines. This study assessed the impact of P. falciparum on placental cytokine profiles between HIV-1 positive and negative women.

Materials and Methods

P. falciparum infection was checked in peripheral and placental blood of HIV-1 negative and positive women by the thick blood smear test. Cytokines proteins and messenger RNAs were quantified by ELISA and real time PCR, respectively. Non-parametric tests were used for statistical analyses.

Results

Placental and peripheral P. falciparum infections were not significantly associated with HIV-1 infection (OR: 1.4; 95% confidence interval (95%CI): 0.5–4.2; p = 0.50 and OR: 0.6; 95%CI: 0.3–1.4; p = 0.26, respectively). Conversely, placental P. falciparum parasitemia was significantly higher in the HIV-1 positive group (p = 0.04). We observed an increase of TNF-α mRNA median levels (p = 0.02) and a trend towards a decrease of IL-10 mRNA (p = 0.07) in placenta from HIV-1 positive women compared to the HIV negative ones leading to a median TNF-α/IL-10 mRNA ratio significantly higher among HIV-1 positive than among HIV-1 negative placenta (p = 0.004; 1.5 and 0.8, respectively). Significant decrease in median secreted cytokine levels were observed in placenta from HIV-1 positive women as compared to the HIV negative however these results are somewhat indicative since it appears that differences in cytokine levels (protein or mRNA) between HIV-1 positive and negative women depend greatly on P.falciparum infection. Within the HIV-1 positive group, TNF-α was the only cytokine significantly associated with clinical parameters linked with HIV-1 MTCT such as premature rupture of membranes, CD4 T-cell number, plasma viral load and delay of NVP intake before delivery.

Conclusions

These results show that P. falciparum infection profoundly modifies the placenta cytokine environment and acts as a confounding factor, masking the impact of HIV-1 in co-infected women. This interplay between the two infections might have implications in the in utero MTCT of HIV-1 in areas where HIV-1 and P. falciparum co-circulate.  相似文献   

5.

Background

Concerns about false-positive HIV results led to a review of testing procedures used in a Médecins Sans Frontières (MSF) HIV programme in Bukavu, eastern Democratic Republic of Congo. In addition to the WHO HIV rapid diagnostic test algorithm (RDT) (two positive RDTs alone for HIV diagnosis) used in voluntary counselling and testing (VCT) sites we evaluated in situ a practical field-based confirmation test against western blot WB. In addition, we aimed to determine the false-positive rate of the WHO two-test algorithm compared with our adapted protocol including confirmation testing, and whether weakly reactive compared with strongly reactive rapid test results were more likely to be false positives.

Methodology/Principal Findings

2864 clients presenting to MSF VCT centres in Bukavu during January to May 2006 were tested using Determine HIV-1/2® and UniGold HIV® rapid tests in parallel by nurse counsellors. Plasma samples on 229 clients confirmed as double RDT positive by laboratory retesting were further tested using both WB and the Orgenics Immunocomb Combfirm® HIV confirmation test (OIC-HIV). Of these, 24 samples were negative or indeterminate by WB representing a false-positive rate of the WHO two-test algorithm of 10.5% (95%CI 6.6-15.2). 17 of the 229 samples were weakly positive on rapid testing and all were negative or indeterminate by WB. The false-positive rate fell to 3.3% (95%CI 1.3–6.7) when only strong-positive rapid test results were considered. Agreement between OIC-HIV and WB was 99.1% (95%CI 96.9–99.9%) with no false OIC-HIV positives if stringent criteria for positive OIC-HIV diagnoses were used.

Conclusions

The WHO HIV two-test diagnostic algorithm produced an unacceptably high level of false-positive diagnoses in our setting, especially if results were weakly positive. The most probable causes of the false-positive results were serological cross-reactivity or non-specific immune reactivity. Our findings show that the OIC-HIV confirmation test is practical and effective in field contexts. We propose that all double-positive HIV RDT samples should undergo further testing to confirm HIV seropositivity until the accuracy of the RDT testing algorithm has been established at programme level.  相似文献   

6.

Background

Testing pregnant women for HIV at the time of labor and delivery is the last opportunity for prevention of mother-to-child HIV transmission (PMTCT) measures, particularly in settings where women do not receive adequate antenatal care. However, HIV testing and counseling of pregnant women in labor is a challenge, especially in resource-constrained settings. In India, many rural women present for delivery without any prior antenatal care. Those who do get antenatal care are not always tested for HIV, because of deficiencies in the provision of HIV testing and counseling services. In this context, we investigated the impact of introducing round-the-clock, rapid, point-of-care HIV testing and counseling in a busy labor ward at a tertiary care hospital in rural India.

Methods and Findings

After they provided written informed consent, women admitted to the labor ward of a rural teaching hospital in India were offered two rapid tests on oral fluid and finger-stick specimens (OraQuick Rapid HIV-1/HIV-2 tests, OraSure Technologies). Simultaneously, venous blood was drawn for conventional HIV ELISA testing. Western blot tests were performed for confirmatory testing if women were positive by both rapid tests and dual ELISA, or where test results were discordant. Round-the-clock (24 h, 7 d/wk) abbreviated prepartum and extended postpartum counseling sessions were offered as part of the testing strategy. HIV-positive women were administered PMTCT interventions. Of 1,252 eligible women (age range 18 y to 38 y) approached for consent over a 9 mo period in 2006, 1,222 (98%) accepted HIV testing in the labor ward. Of these, 1,003 (82%) women presented with either no reports or incomplete reports of prior HIV testing results at the time of admission to the labor ward. Of 1,222 women, 15 were diagnosed as HIV-positive (on the basis of two rapid tests, dual ELISA and Western blot), yielding a seroprevalence of 1.23% (95% confidence interval [CI] 0.61%–1.8%). Of the 15 HIV test–positive women, four (27%) had presented with reported HIV status, and 11 (73%) new cases of HIV infection were detected due to rapid testing in the labor room. Thus, 11 HIV-positive women received PMTCT interventions on account of round-the-clock rapid HIV testing and counseling in the labor room. While both OraQuick tests (oral and finger-stick) were 100% specific, one false-negative result was documented (with both oral fluid and finger-stick specimens). Of the 15 HIV-infected women who delivered, 13 infants were HIV seronegative at birth and at 1 and 4 mo after delivery; two HIV-positive infants died within a month of delivery.

Conclusions

In a busy rural labor ward setting in India, we demonstrated that it is feasible to introduce a program of round-the-clock rapid HIV testing, including prepartum and extended postpartum counseling sessions. Our data suggest that the availability of round-the-clock rapid HIV testing resulted in successful documentation of HIV serostatus in a large proportion (82%) of rural women who were unaware of their HIV status when admitted to the labor room. In addition, 11 (73%) of a total of 15 HIV-positive women received PMTCT interventions because of round-the-clock rapid testing in the labor ward. These findings are relevant for PMTCT programs in developing countries.  相似文献   

7.

Background

This study evaluated two models of routine HIV testing of hospitalized children in a high HIV-prevalence resource-constrained African setting. Both models incorporated “task shifting,” or the allocation of tasks to the least-costly, capable health worker.

Methods and Findings

Two models were piloted for three months each within the pediatric department of a referral hospital in Lilongwe, Malawi between January 1 and June 30, 2008. Model 1 utilized lay counselors for HIV testing instead of nurses and clinicians. Model 2 further shifted program flow and advocacy responsibilities from counselors to volunteer parents of HIV-infected children, called “patient escorts.” A retrospective review of data from 6318 hospitalized children offered HIV testing between January-December 2008 was conducted. The pilot quarters of Model 1 and Model 2 were compared, with Model 2 selected to continue after the pilot period. There was a 2-fold increase in patients offered HIV testing with Model 2 compared with Model 1 (43.1% vs 19.9%, p<0.001). Furthermore, patients in Model 2 were younger (17.3 vs 26.7 months, p<0.001) and tested sooner after admission (1.77 vs 2.44 days, p<0.001). There were no differences in test acceptance or enrollment rates into HIV care, and the program trends continued 6 months after the pilot period. Overall, 10244 HIV antibody tests (4779 maternal; 5465 child) and 453 DNA-PCR tests were completed, with 97.8% accepting testing. 19.6% of all mothers (n = 1112) and 8.5% of all children (n = 525) were HIV-infected. Furthermore, 6.5% of children were HIV-exposed (n = 405). Cumulatively, 72.9% (n = 678) of eligible children were evaluated in the hospital by a HIV-trained clinician, and 68.3% (n = 387) successfully enrolled into outpatient HIV care.

Conclusions/Significance

The strategy presented here, task shifting from lay counselors alone to lay counselors and patient escorts, greatly improved program outcomes while only marginally increasing operational costs. The wider implementation of this strategy could accelerate pediatric HIV care access in high-prevalence settings.  相似文献   

8.

Introduction

Kaposi sarcoma (KS) is the leading cause of cancer in Uganda and occurs in people with and without HIV. Human herpesvirus-8 (HHV-8) replication is important both in transmission of HHV-8 and progression to KS. We characterized the sites and frequency of HHV-8 detection in Ugandans with and without HIV and KS.

Methods

Participants were enrolled into one of four groups on the basis of HIV and KS status (HIV negative/KS negative, HIV positive/KS negative, HIV negative/KS positive, and HIV positive/KS positive). Participants collected oral swabs daily and clinicians collected oral swabs, anogenital swabs, and plasma samples weekly over 4 weeks. HHV-8 DNA at each site was quantified by polymerase chain reaction (PCR).

Results

78 participants collected a total of 2063 orals swabs and 358 plasma samples. Of these, 428 (21%) oral swabs and 96 (27%) plasma samples had detectable HHV-8 DNA. HHV-8 was detected more frequently in both the oropharynx of persons with KS (24 (57%) of 42 persons with KS vs. 8 (22%) of 36 persons without, p = 0.002) and the peripheral blood (30 (71%) of 42 persons with KS vs. 8 (22%) of 36 persons without, p<0.001). In a multivariate model, HHV-8 viremia was more frequent among men (IRR = 3.3, 95% CI = 1.7–6.2, p<0.001), persons with KS (IRR = 3.9, 95% CI = 1.7–9.0, p = 0.001) and persons with HIV infection (IRR = 1.7, 95% CI = 1.0–2.7, p = 0.03). Importantly, oral HHV-8 detection predicted the subsequent HHV-8 viremia. HHV-8 viremia was significantly more common when HHV-8 DNA was detected from the oropharynx during the week prior than when oral HHV-8 was not detected (RR = 3.3, 95% CI = 1.8–5.9 p<0.001). Genital HHV-8 detection was rare (9 (3%) of 272 swabs).

Conclusions

HHV-8 detection is frequent in the oropharynx and peripheral blood of Ugandans with endemic and epidemic KS. Replication at these sites is highly correlated, and viremia is increased in men and those with HIV. The high incidence of HHV-8 replication at multiple anatomic sites may be an important factor leading to and sustaining the high prevalence of KS in Uganda.  相似文献   

9.

Background

FcRγ is an immunoreceptor tyrosine-based activation motif (ITAM)-signalling protein essential for immunoreceptor signaling and monocyte, macrophage and NK cell function. Previous study from our laboratory showed that FcRγ is down-regulated in HIV-infected macrophages in vitro. FcRγ expression in immune cells present in HIV-infected individuals is unknown.

Methodology/Principal Findings

We compared FcRγ expression in peripheral blood mononuclear cells isolated from HIV-1-infected individuals receiving combination antiretroviral therapy and healthy, HIV-1-uninfected individuals. FcRγ mRNA and protein levels were measured using quantitative real-time PCR and immunoblotting, respectively. CD56+ CD94+ lymphocytes isolated from blood of HIV-1 infected individuals had reduced FcRγ protein expression compared to HIV-uninfected individuals (decrease = 76.8%, n = 18 and n = 12 respectively, p = 0.0036). In a second group of patients, highly purified NK cells had reduced FcRγ protein expression compared to uninfected controls (decrease = 50.2%, n = 9 and n = 8 respectively, p = 0.021). Decreased FcRγ expression in CD56+CD94+ lymphocytes was associated with reduced mRNA (51.7%, p = 0.021) but this was not observed for the smaller group of patients analysed for NK cell expression (p = 0.36).

Conclusion/Significance

These data suggest biochemical defects in ITAM-dependent signalling within NK cells in HIV-infected individuals which is present in the context of treatment with combination antiretroviral therapy.  相似文献   

10.
Progenitor cell therapies show great promise, but their potential for clinical applications requires improved storage and transportation. Desiccated cells stored at ambient temperature would provide economic and practical advantages over approaches employing cell freezing and subzero temperature storage. The objectives of this study were to assess a method for loading the stabilizing sugar, trehalose, into hematopoietic stem and progenitor cells (HPC) and to evaluate the effects of subsequent freeze-drying and storage at ambient temperature on differentiation and clonogenic potential. HPC were isolated from human umbilical cord blood and loaded with trehalose using an endogenous cell surface receptor, termed P2Z. Solution containing trehalose-loaded HPC was placed into vials, which were transferred to a tray freeze-dryer and removed during each step of the freeze-drying process to assess differentiation and clonogenic potential. Control groups for these experiments were freshly isolated HPC. Control cells formed 1450±230 CFU-GM, 430±140 BFU-E, and 50±40 CFU-GEMM per 50 µL. Compared to the values for the control cells, there was no statistical difference observed for cells removed at the end of the freezing step or at the end of primary drying. There was a gradual decrease in the number of CFU-GM and BFU-E for cells removed at different temperatures during secondary drying; however, there were no significant differences in the number of CFU-GEMM. To determine storage stability of lyophilized HPC, cells were stored for 4 weeks at 25°C in the dark. Cells reconstituted immediately after lyophilization produced 580±90 CFU-GM (∼40%, relative to unprocessed controls p<0.0001), 170±70 BFU-E (∼40%, p<0.0001), and 41±22 CFU-GEMM (∼82%, p = 0.4171), and cells reconstituted after 28 days at room temperature produced 513±170 CFU-GM (∼35%, relative to unprocessed controls, p<0.0001), 112±68 BFU-E (∼26%, p<0.0001), and 36±17 CFU-GEMM (∼82%, p = 0.2164) These studies are the first to document high level retention of CFU-GEMM following lyophilization and storage for 4 weeks at 25°C. This type of flexible storage stability would potentially permit the ability to ship and store HPC without the need for refrigeration.  相似文献   

11.
12.

Background and Purpose

Asymptomatic central nervous system (CNS) involvement occurs in the early stage of the human immunodeficiency virus (HIV) infection. It has been documented that the hepatitis C virus (HCV) can replicate in the CNS. The aim of the study was to evaluate early disturbances in cerebral microcirculation using magnetic resonance (MR) perfusion-weighted imaging (PWI) in asymptomatic HIV-1-positive and HCV-positive patients, as well as to assess the correlation between PWI measurements and the clinical data.

Materials and Methods

Fifty-six patients: 17 HIV-1-positive non-treated, 18 HIV-1-positive treated with combination antiretroviral therapy (cART), 7 HIV-1/HCV-positive non-treated, 14 HCV-positive before antiviral therapy and 18 control subjects were enrolled in the study. PWI was performed with a 1.5T MR unit using dynamic susceptibility contrast (DSC) method. Cerebral blood volume (CBV) measurements relative to cerebellum (rCBV) were evaluated in the posterior cingulated region (PCG), basal ganglia (BG), temporoparietal (TPC) and frontal cortices (FC), as well as in white matter of frontoparietal areas. Correlations of rCBV values with immunologic data and liver histology activity index (HAI) were analyzed.

Results

Significantly lower rCBV values were found in the right TPC and left FC as well as in PCG in HIV-1-positive naïve (p = 0.009; p = 0.020; p = 0.012), HIV-1 cART treated (p = 0.007; p = 0.009; p = 0.033), HIV-1/HCV-positive (p = 0.007; p = 0.027; p = 0.045) and HCV-positive patients (p = 0.010; p = 0.005; p = 0.045) compared to controls. HIV-1-positive cART treated and HIV-1/HCV-positive patients demonstrated lower rCBV values in the right FC (p = 0.009; p = 0.032, respectively) and the left TPC (p = 0.036; p = 0.005, respectively), while HCV-positive subjects revealed lower rCBV values in the left TPC region (p = 0.003). We found significantly elevated rCBV values in BG in HCV-positive patients (p = 0.0002; p<0.0001) compared to controls as well as to all HIV-1-positive subjects. There were no significant correlations of rCBV values and CD4 T cell count or HAI score.

Conclusions

PWI examination enables the assessment of HIV-related as well as HCV-related early cerebral dysfunction in asymptomatic subjects. HCV-infected patients seem to reveal the most pronounced perfusion changes.  相似文献   

13.

Background

HIV-1 RNA plasma concentration at viral set-point is associated not only with disease outcome but also with the transmission dynamics of HIV-1. We investigated whether plasma HIV-1 RNA concentration and CD4 cell count at viral set-point have changed over time in the HIV epidemic in the Netherlands.

Methodology/Principal Findings

We selected 906 therapy-naïve patients with at least one plasma HIV-1 RNA concentration measured 9 to 27 months after estimated seroconversion. Changes in HIV-1 RNA and CD4 cell count at viral set-point over time were analysed using linear regression models. The ATHENA national observational cohort contributed all patients who seroconverted in or after 1996; the Amsterdam Cohort Studies (ACS) contributed seroconverters before 1996. The mean of the first HIV-1 RNA concentration measured 9–27 months after seroconversion was 4.30 log10 copies/ml (95% CI 4.17–4.42) for seroconverters from 1984 through 1995 (n = 163); 4.27 (4.16–4.37) for seroconverters 1996–2002 (n = 232), and 4.59 (4.52–4.66) for seroconverters 2003–2007 (n = 511). Compared to patients seroconverting between 2003–2007, the adjusted mean HIV-1 RNA concentration at set-point was 0.28 log10 copies/ml (95% CI 0.16–0.40; p<0.0001) and 0.26 (0.11–0.41; p = 0.0006) lower for those seroconverting between 1996–2002 and 1984–1995, respectively. Results were robust regardless of type of HIV-1 RNA assay, HIV-1 subtype, and interval between measurement and seroconversion. CD4 cell count at viral set-point declined over calendar time at approximately 5 cells/mm3/year.

Conclusion

The HIV-1 RNA plasma concentration at viral set-point has increased over the last decade of the HIV epidemic in the Netherlands. This is accompanied by a decreasing CD4 cell count over the period 1984–2007 and may have implications for both the course of the HIV infection and the epidemic.  相似文献   

14.

Background

The performance of the tuberculosis specific Interferon Gamma Release Assays (IGRAs) has not been sufficiently documented in tuberculosis- and HIV-endemic settings. This study evaluated the sensitivity of the QuantiFERON TB-Gold In-Tube (QFT-IT) in patients with culture confirmed pulmonary tuberculosis (PTB) in a TB- and HIV-endemic population and the effect of HIV-infection and CD4 cell count on test performance.

Methodology/Principal Findings

161 patients with sputum culture confirmed PTB were subjected to HIV- and QFT-IT testing and measurement of CD4 cell count. The QFT-IT was positive in 74% (119/161; 95% CI: 67–81%). Sensitivity was higher in HIV-negative (75/93) than in HIV-positive (44/68) patients (81% vs. 65%, p = 0.02) and increased with CD4 cell count in HIV-positive patients (test for trend p = 0.03). 23 patients (14%) had an indeterminate result and this proportion decreased with increasing CD4 cell count in HIV-positive patients (test for trend p = 0.03). Low CD4 cell count (<300 cells/µl) did not account for all QFT-IT indeterminate nor all negative results. Sensitivity when excluding indeterminate results was 86% (95% CI: 81–92%) and did not differ between HIV-negative and HIV–positive patients (88 vs. 83%, p = 0.39).

Conclusions/Significance

Sensitivity of the QFT-IT for diagnosing active PTB infection was reasonable when excluding indeterminate results and in HIV-negative patients. However, since the test missed more than 10% of patients, its potential as a rule-out test for active TB disease is limited. Furthermore, test performance is impaired by low CD4 cell count in HIV-positive patients and possibly by other factors as well in both HIV-positive and HIV-negative patients. This might limit the potential of the test in populations where HIV-infection is prevalent.  相似文献   

15.

Background

Some HIV infected individuals remain asymptomatic for protracted periods of time in the absence of antiretroviral therapy (ART). Virological control, CD4 T cell loss and HIV-specific responses are some of the key interrelated determinants of HIV-1 disease progression. In this study, possible interactions between viral load, CD4 T cell slopes, host genetics and HIV-specific IFN-γ responses were evaluated in chronically HIV-1-infected adults.

Methodolology/Principal Findings

Multilevel regression modeling was used to stratify clade A or D HIV-infected individuals into disease progression groups based on CD4 T cell slopes. ELISpot assays were used to quantify the frequency and magnitude of HIV-induced IFN-γ responses in 7 defined rapid progressors (RPs) and 14 defined slow progressors (SPs) at a single time point. HLA typing was performed using reference strand conformational analysis (RSCA). Although neither the breadth nor the magnitude of the proteome-wide HIV-specific IFN-γ response correlated with viral load, slow disease progression was associated with over-representation of host immunogenetic protective HLA B* alleles (10 of 14 SPs compared to 0 of 7; p = 0.004, Fisher''s Exact) especially B*57 and B*5801, multiclade Gag T-cell targeting (71%, 10 of 14 SPs compared to 14%, 1 of 7 RPs); p = 0.029, Fisher''s Exact test and evident virological control (3.65 compared to 5.46 log10 copies/mL in SPs and RPs respectively); p<0.001, unpaired student''s t-test

Conclusions

These data are consistent with others that associated protection from HIV disease with inherent host HLA B allele-mediated ability to induce broader Gag T-cell targeting coupled with apparent virological control. These immunogenetic features of Gag-specific immune response which could influence disease progression may provide useful insight in future HIV vaccine design.  相似文献   

16.
Successful antiretroviral pre-exposure prophylaxis (PrEP) for mucosal and intravenous HIV-1 transmission could reduce new infections among targeted high-risk populations including discordant couples, injection drug users, high-risk women and men who have sex with men. Targeted antiretroviral PrEP could be particularly effective at slowing the spread of HIV-1 if a single antiretroviral combination were found to be broadly protective across multiple routes of transmission. Therefore, we designed our in vivo preclinical study to systematically investigate whether rectal and intravenous HIV-1 transmission can be blocked by antiretrovirals administered systemically prior to HIV-1 exposure. We performed these studies using a highly relevant in vivo model of mucosal HIV-1 transmission, humanized Bone marrow/Liver/Thymus mice (BLT). BLT mice are susceptible to HIV-1 infection via three major physiological routes of viral transmission: vaginal, rectal and intravenous. Our results show that BLT mice given systemic antiretroviral PrEP are efficiently protected from HIV-1 infection regardless of the route of exposure. Specifically, systemic antiretroviral PrEP with emtricitabine and tenofovir disoproxil fumarate prevented both rectal (Chi square = 8.6, df = 1, p = 0.003) and intravenous (Chi square = 13, df = 1, p = 0.0003) HIV-1 transmission. Our results indicate that antiretroviral PrEP has the potential to be broadly effective at preventing new rectal or intravenous HIV transmissions in targeted high risk individuals. These in vivo preclinical findings provide strong experimental evidence supporting the potential clinical implementation of antiretroviral based pre-exposure prophylactic measures to prevent the spread of HIV/AIDS.  相似文献   

17.

Background

Aspirin is a cornerstone in prevention of cardiovascular events and modulates both platelet aggregation and fibrin clot formation. Some patients experience cardiovascular events whilst on aspirin, often termed aspirin treatment failure (ATF). This study evaluated both platelet aggregation and fibrin clot structure in patients with ATF.

Methods

We included 177 stable coronary artery disease patients on aspirin monotherapy. Among these, 116 (66%) had ATF defined as myocardial infarction (MI) whilst on aspirin. Platelet aggregation was assessed by Multiplate® aggregometry and VerifyNow®, whereas turbidimetric assays and scanning electron microscopy were employed to study fibrin clot characteristics.

Results

Enhanced platelet aggregation was observed in patients with ATF compared with non-MI patients following stimulation with arachidonic acid 1.0 mM (median 161 (IQR 95; 222) vs. 97 (60; 1776) AU*min, p = 0.005) and collagen 1.0 µg/mL (293 (198; 427) vs. 220 (165; 370) AU*min, p = 0.03). Similarly, clot maximum absorbance, a measure of fibrin network density, was increased in patients with ATF (0.48 (0.41; 0.52) vs. 0.42 (0.38; 0.50), p = 0.02), and this was associated with thinner fibres (mean ± SD: 119.7±27.5 vs. 127.8±31.1 nm, p = 0.003) and prolonged lysis time (552 (498; 756) vs. 519 (468; 633) seconds; p = 0.02). Patients with ATF also had increased levels of C-reactive protein (CRP) (1.34 (0.48; 2.94) and 0.88 (0.32; 1.77) mg/L, p = 0.01) compared with the non-MI group. Clot maximum absorbance correlated with platelet aggregation (r = 0.31–0.35, p-values<0.001) and CRP levels (r = 0.60, p<0.001).

Conclusions

Patients with aspirin treatment failure showed increased platelet aggregation and altered clot structure with impaired fibrinolysis compared with stable CAD patients without previous MI. These findings suggest that an increased risk of aspirin treatment failure may be identified by measuring both platelet function and fibrin clot structure.  相似文献   

18.

Objective

The objective of this work was to compare two generic questionnaires assessing patients’ satisfaction with medication. In addition we tested whether satisfaction can predict adherence to medication regimens in patients with chronic diseases, and which dimensions of satisfaction are most involved.

Methods

This prospective, observational study was conducted over one year in a heterogeneous population of patients with various chronic diseases. Satisfaction with medication was assessed by using the TSQM® vII and the SatMed-Q® questionnaires, and adherence to treatment was assessed with the Morisky-Green questionnaire. Clinical pharmacists interviewed patients to collect clinical, demographic and therapeutic data.

Results

190 patients were enrolled. Both questionnaires showed excellent reliability and correlation was high (R = 0.70; p<0.001). Adherence was correlated with satisfaction with medication whether assessed with the SatMed-Q® (R = 0.23; p = 0.002) or the TSQM® (R = 0.17; p = 0.02). Among different dimensions of satisfaction, convenience of use and side effects are prominent predictors of adherence.

Conclusion

Adherence is related to the patient’s satisfaction with medication whether assessed with the TSQM® vII or the SatMed-Q®. Therefore, these simple questionnaires could be used as predictive tools to identify patients whos’ adherence needs to be improved.  相似文献   

19.

Background

The diagnosis of smear-negative or sputum-scarce tuberculosis (TB) is problematic as culture takes several weeks and representative biological samples are difficult to obtain. RD-1 antigen-specific interferon-γ release assays (IGRAs) are sensitive and specific blood-based tests for the diagnosis of M. tuberculosis infection. The feasibility and diagnostic utility of this rapid immunodiagnostic assay, using cells from induced sputum, is unknown.

Methodology/Principal Findings

Cells isolated from induced sputum were co-cultured with ESAT-6 and CFP-10 antigens using a standardized enzyme-linked immunospot (ELISPOT) assay (T-SPOT®.TB) in 101 consecutively recruited TB suspects or non-TB controls. An optimization phase using 28 samples was followed by a validation phase using samples from 73 participants (20 with definite or probable TB, and 48 with non-TB). Despite optimization of sputum processing 65/73 (89%) of the IGRAs in the validation phase were inconclusive. 44/73 (60%) tests failed due to sputum induction-related factors [sputum induction-related adverse events (n = 5), inadequate sputum volume (n = 8), non-homogenisable sputum (n = 7), and insufficient numbers of cells to perform the assay (n = 24)], whilst 20/73 (27%) tests failed due T-SPOT®.TB assay-related factors [excessive debris precluding reading of spots in the ELISPOT well (n = 6), failure of the positive control (n = 11), or high spot count in the negative control (n = 3)]. Only 8/73 (11%) of the available samples could therefore be correctly categorized (7 definite or probable TB, and 1 non-TB patient). Thus, 13/20 (65%) of the definite or probable TB cases remained undiagnosed.

Conclusions/Significance

Rapid immunodiagnosis of pulmonary TB by antigen-specific IFN-γ ELISPOT responses, using cells from induced sputum, is possible. However, the test, in its current ELISPOT format, is not clinically useful because the majority of the assays are inconclusive.  相似文献   

20.

Background

Current laboratory and point-of-care tests for HIV detect different analytes and use different sample types. Some have fast turnaround times (<1 hour). We investigated how HIV test choice could impact case finding by testing programs.

Methods

We analyzed 21,234 consecutive HIV tests with venous blood obtained by San Francisco HIV testing programs from 2003 to 2008. For a subset, oral fluid (n = 6446) or fingerstick blood (n = 8127) samples were also obtained for rapid testing. In all cases, HIV status was determined using an HIV antibody-plus-RNA test algorithm. We assessed how the screening antibody tests performed individually versus the gold standard of the full algorithm. We then evaluated the potential ability of other tests (including new tests) to detect more cases, by re-testing all specimens that had negative/discrepant antibody results on initial screening.

Findings

The antibody-RNA algorithm identified 58 acute and 703 established HIV infection cases. 1st-generation (Vironostika) and 3rd-generation (Genetic Systems) immunoassays had 92 and 96 percent sensitivity, respectively. The Oraquick rapid test had clinical sensitivity of only 86 percent on oral fluid samples, but 92 percent on finger-stick blood. Newer 4th-generation, antigen-antibody combo rapid immunoassay (ARCHITECT) detected HIV in 87 percent of all the acute cases that had been missed by one of the previous screening assays. A point-of-care 4th generation antigen-antibody combo rapid test (Determine) detected about 54 percent of such acute cases.

Conclusions

Our study suggests that some rapid antibody blood tests will give similar case detection to laboratory antibody tests, but that oral fluid testing greatly reduces ability to detect HIV. New 4th-generation combo tests can detect the majority of acute infections detectable by HIV RNA but with rapid results. Using these tests as a primary screening assay in high-risk HIV testing programs could reduce or eliminate the need for HIV RNA testing.  相似文献   

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