8 research outputs found
A multi-country comparative study of two treponemal tests for the serodiagnosis of Syphilis amongst Men Who Have Sex with Men (MSM):Chemo-luminescent assay vs Treponema pallidum particle agglutination assay
Introduction:International guidelines recommend routine screening for syphilis amongst keypopulations and vulnerable populations using tests detecting treponemal and nontreponemalantibodies. Whilst treponemal tests have high sensitivities and specificities,they differ regarding subjective or objective interpretation, throughput and workload.CLIAs are cost- and time-effective automated methods for detecting treponemalantibodies. The TPPA has been considered the “gold standard” treponemal assay,however, this includes a highly manual procedure, low throughput and subjectiveinterpretation. The present multi-country study evaluated the ADVIA Centaur® SyphilisCLIA assay compared to the reference SERODIA-TP·PA® for the serodiagnosis ofsyphilis amongst MSM.Method:1,485 MSM were enrolled in Brighton (UK), Malta, and Verona (Italy) as part of a largerWHO multi-country and multi-site ProSPeRo study. Serum was tested with the CLIAassay and TP·PA, in accordance with the manufacturers’ instructions, for a first roundof validation. A second round of validation was carried out for discrepant results thatwere additionally tested with both Western Blot and an Immunoblot.Sensitivity, specificity, positive and negative predictive value (PPV and NPV), likelihoodratios (positive/negative), and the Diagnostic Odds Ratio (DOR)/pre-post-testprobability were calculated.Results:Out of 1,485 eligible samples analysed in the first phase, the SERODIATP·PA identified 360 positive and 1,125 negative cases. The CLIA assay identified 366positives, missclassifying one TPPA-positive sample. In the second phase, the CLIAresulted in 1 false negative and 4 false positive results. Considering the syphilis studyprevalence of 24% (95% CI: 22-26.7), The sensitivity of the ADVIA Centaur® SyphilisCLIA assay was 99.7% (95% CI: 98.5-100), and the specificity was 99.4% (95% CI:98.7-99.7). The ROC area values were 0.996 (95% CI: 0.992-0.999), and both the PPVand NPV values were above 98%Conclusions:The CLIA assay showed similar performance compared to the SERODIA-TP·PA.Considering the study is based on QUADAS principles and with a homogeneouspopulation, results are also likely to be generalisable to MSM population but potentiallynot applicable to lower prevalence populations routinely screened for syphilis. Theautomated CLIA treponemal assay confirmed to be accurate and appropriate forroutine initial syphilis screening, i.e. when the reverse testing algorithm is applied
Adjunctive rifampicin for Staphylococcus aureus bacteraemia (ARREST): a multicentre, randomised, double-blind, placebo-controlled trial.
BACKGROUND: Staphylococcus aureus bacteraemia is a common cause of severe community-acquired and hospital-acquired infection worldwide. We tested the hypothesis that adjunctive rifampicin would reduce bacteriologically confirmed treatment failure or disease recurrence, or death, by enhancing early S aureus killing, sterilising infected foci and blood faster, and reducing risks of dissemination and metastatic infection. METHODS: In this multicentre, randomised, double-blind, placebo-controlled trial, adults (≥18 years) with S aureus bacteraemia who had received ≤96 h of active antibiotic therapy were recruited from 29 UK hospitals. Patients were randomly assigned (1:1) via a computer-generated sequential randomisation list to receive 2 weeks of adjunctive rifampicin (600 mg or 900 mg per day according to weight, oral or intravenous) versus identical placebo, together with standard antibiotic therapy. Randomisation was stratified by centre. Patients, investigators, and those caring for the patients were masked to group allocation. The primary outcome was time to bacteriologically confirmed treatment failure or disease recurrence, or death (all-cause), from randomisation to 12 weeks, adjudicated by an independent review committee masked to the treatment. Analysis was intention to treat. This trial was registered, number ISRCTN37666216, and is closed to new participants. FINDINGS: Between Dec 10, 2012, and Oct 25, 2016, 758 eligible participants were randomly assigned: 370 to rifampicin and 388 to placebo. 485 (64%) participants had community-acquired S aureus infections, and 132 (17%) had nosocomial S aureus infections. 47 (6%) had meticillin-resistant infections. 301 (40%) participants had an initial deep infection focus. Standard antibiotics were given for 29 (IQR 18-45) days; 619 (82%) participants received flucloxacillin. By week 12, 62 (17%) of participants who received rifampicin versus 71 (18%) who received placebo experienced treatment failure or disease recurrence, or died (absolute risk difference -1·4%, 95% CI -7·0 to 4·3; hazard ratio 0·96, 0·68-1·35, p=0·81). From randomisation to 12 weeks, no evidence of differences in serious (p=0·17) or grade 3-4 (p=0·36) adverse events were observed; however, 63 (17%) participants in the rifampicin group versus 39 (10%) in the placebo group had antibiotic or trial drug-modifying adverse events (p=0·004), and 24 (6%) versus six (2%) had drug interactions (p=0·0005). INTERPRETATION: Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S aureus bacteraemia. FUNDING: UK National Institute for Health Research Health Technology Assessment
CSF1R inhibitor JNJ-40346527 attenuates microglial proliferation and neurodegeneration in P301S mice
Neuroinflammation and microglial activation are significant processes in Alzheimer’s disease pathology. Recent genome-wide association studies have highlighted multiple immune-related genes in association with Alzheimer’s disease, and experimental data have demonstrated microglial proliferation as a significant component of the neuropathology. In this study, we tested the efficacy of the selective CSF1R inhibitor JNJ-40346527 (JNJ-527) in the P301S mouse tauopathy model. We first demonstrated the anti-proliferative effects of JNJ-527 on microglia in the ME7 prion model, and its impact on the inflammatory profile, and provided potential CNS biomarkers for clinical investigation with the compound, including pharmacokinetic/pharmacodynamics and efficacy assessment by TSPO autoradiography and CSF proteomics. Then, we showed for the first time that blockade of microglial proliferation and modification of microglial phenotype leads to an attenuation of tau-induced neurodegeneration and results in functional improvement in P301S mice. Overall, this work strongly supports the potential for inhibition of CSF1R as a target for the treatment of Alzheimer’s disease and other tau-mediated neurodegenerative diseases
Inflammatory biomarkers in Alzheimer's disease plasma
Introduction:Plasma biomarkers for Alzheimer’s disease (AD) diagnosis/stratification are a“Holy Grail” of AD research and intensively sought; however, there are no well-established plasmamarkers.Methods:A hypothesis-led plasma biomarker search was conducted in the context of internationalmulticenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL;259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed.Results:Ten analytes showed significant intergroup differences. Logistic regression identified five(FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APOε4 adjusted, optimally differentiated AD andCTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI(AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Twoanalytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71).Discussion:Plasma markers of inflammation and complement dysregulation support diagnosis andoutcome prediction in AD and MCI. Further replication is needed before clinical translatio
A multi-country comparative study of two treponemal tests for the serodiagnosis of syphilis amongst men who have sex with men (MSM): Chemo-luminescent assay vs Treponema pallidum particle agglutination assay
Introduction: International guidelines recommend routine screening for syphilis (aetiological agent: Treponema pallidum subspecies pallidum) amongst key populations and vulnerable populations using tests detecting treponemal and non-treponemal antibodies. Whilst treponemal tests have high sensitivities and specificities, they differ regarding subjective or objective interpretation, throughput and workload. Chemiluminescence immunoassays (CLIAs) are cost- and time-effective automated methods for detecting treponemal antibodies. The Treponema pallidum particle agglutination assay (TPPA) has been considered the “gold standard” treponemal assay, however, this includes a highly manual procedure, low throughput and subjective interpretation. The present multi-country study evaluated the ADVIA Centaur® Syphilis CLIA (Siemens Healthcare) assay compared to the reference SERODIA-TP·PA® (Fujirebio Diagnostics) for the serodiagnosis of syphilis amongst men who have sex with men (MSM). Method: 1,485 MSM were enrolled in Brighton (UK), Malta, and Verona (Italy) as part of a larger WHO multi-country and multi-site ProSPeRo study. Ethical approval was obtained. Serum was tested with the ADVIA Centaur® Syphilis CLIA assay and SERODIA-TP·PA®, in accordance with the manufacturers’ instructions, for a first round of validation. A second round of validation was carried out for discrepant results that were additionally tested with both Western Blot (Westernblot EUROIMMUN®) and an Immunoblot (INNO-LIA, Fujirebio Diagnostics). Sensitivity, specificity, positive and negative predictive value (PPV and NPV), likelihood ratios (positive/negative), and the Diagnostic Odds Ratio (DOR)/pre-post-test probability (Fagan's nomogram) were calculated. Results: Out of 1,485 eligible samples analysed in the first phase, the SERODIA-TP·PA® identified 360 positive and 1,125 negative cases. The ADVIA Centaur® Syphilis CLIA assay (Siemens) identified 366 positives, missclassifying one TPPA-positive sample. In the second phase, the ADVIA Centaur® Syphilis CLIA resulted in 1 false negative and 4 false positive results. Considering the syphilis study prevalence of 24% (95% CI: 22–26.7), The sensitivity of the ADVIA Centaur® Syphilis CLIA assay was 99.7% (95% CI: 98.5–100), and the specificity was 99.4% (95% CI: 98.7–99.7). The ROC area values were 0.996 (95% CI: 0.992–0.999), and both the PPV and NPV values were above 98% (PPV 98.1%, 95% CI: 96.1–99.2; NPV 99.9%, 95% CI: 99.5–100). Conclusions: The ADVIA Centaur® Syphilis CLIA assay showed similar performance compared to the SERODIA-TP·PA®. Considering the study is based on QUADAS principles and with a homogeneous population, results are also likely to be generalisable to MSM population but potentially not applicable to lower prevalence populations routinely screened for syphilis. The automated CLIA treponemal assay confirmed to be accurate and appropriate for routine initial syphilis screening, i.e. when the reverse testing algorithm is applied.</p
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A multi-country comparative study of two treponemal tests for the serodiagnosis of syphilis amongst men who have sex with men (MSM): Chemo-luminescent assay vs Treponema pallidum particle agglutination assay
Introduction: International guidelines recommend routine screening for syphilis (aetiological agent: Treponema pallidum subspecies pallidum) amongst key populations and vulnerable populations using tests detecting treponemal and non-treponemal antibodies. Whilst treponemal tests have high sensitivities and specificities, they differ regarding subjective or objective interpretation, throughput and workload. Chemiluminescence immunoassays (CLIAs) are cost- and time-effective automated methods for detecting treponemal antibodies. The Treponema pallidum particle agglutination assay (TPPA) has been considered the “gold standard” treponemal assay, however, this includes a highly manual procedure, low throughput and subjective interpretation. The present multi-country study evaluated the ADVIA Centaur® Syphilis CLIA (Siemens Healthcare) assay compared to the reference SERODIA-TP·PA® (Fujirebio Diagnostics) for the serodiagnosis of syphilis amongst men who have sex with men (MSM). Method: 1,485 MSM were enrolled in Brighton (UK), Malta, and Verona (Italy) as part of a larger WHO multi-country and multi-site ProSPeRo study. Ethical approval was obtained. Serum was tested with the ADVIA Centaur® Syphilis CLIA assay and SERODIA-TP·PA®, in accordance with the manufacturers’ instructions, for a first round of validation. A second round of validation was carried out for discrepant results that were additionally tested with both Western Blot (Westernblot EUROIMMUN®) and an Immunoblot (INNO-LIA, Fujirebio Diagnostics). Sensitivity, specificity, positive and negative predictive value (PPV and NPV), likelihood ratios (positive/negative), and the Diagnostic Odds Ratio (DOR)/pre-post-test probability (Fagan's nomogram) were calculated. Results: Out of 1,485 eligible samples analysed in the first phase, the SERODIA-TP·PA® identified 360 positive and 1,125 negative cases. The ADVIA Centaur® Syphilis CLIA assay (Siemens) identified 366 positives, missclassifying one TPPA-positive sample. In the second phase, the ADVIA Centaur® Syphilis CLIA resulted in 1 false negative and 4 false positive results. Considering the syphilis study prevalence of 24% (95% CI: 22–26.7), The sensitivity of the ADVIA Centaur® Syphilis CLIA assay was 99.7% (95% CI: 98.5–100), and the specificity was 99.4% (95% CI: 98.7–99.7). The ROC area values were 0.996 (95% CI: 0.992–0.999), and both the PPV and NPV values were above 98% (PPV 98.1%, 95% CI: 96.1–99.2; NPV 99.9%, 95% CI: 99.5–100). Conclusions: The ADVIA Centaur® Syphilis CLIA assay showed similar performance compared to the SERODIA-TP·PA®. Considering the study is based on QUADAS principles and with a homogeneous population, results are also likely to be generalisable to MSM population but potentially not applicable to lower prevalence populations routinely screened for syphilis. The automated CLIA treponemal assay confirmed to be accurate and appropriate for routine initial syphilis screening, i.e. when the reverse testing algorithm is applied.</p
Independent clinic-based evaluation of dual POCTs for screening for HIV and syphilis in men who have sex with men in Italy, Malta, Peru, and the United Kingdom
Introduction: Globally, the incidence of HIV and syphilis can be reduced by the use of validated point of care tests (POCTs). As part of the WHO PRoSPeRo Network, we aimed to evaluate the performance, acceptability, and operational characteristics of two dual HIV/syphilis POCTs (Bioline HIV/Syphilis Duo (Abbott) and DPP® HIV-Syphilis assay (Chembio) for the screening of HIV and syphilis amongst men who have sex with men (MSM).Method and analyses: A cross sectional study of 2,577 MSM in Italy, Malta, Peru, and the United Kingdom (UK) presenting to seven clinic sites, were enrolled. Finger prick blood was collected to perform POCTs and results compared with standard laboratory investigations on venepuncture blood. Acceptability and operational characteristics were assessed using questionnaires. Diagnostic meta-analysis was used to combine data from the evaluation sites. Results: Based on laboratory tests, 23.46% (n=598/2549) of participants were confirmed HIV positive, and 35.88% of participants (n=901/2511) were positive on treponemal reference testing. Of all participants showing evidence of antibodies to Treponema pallidum, 50.56% (n=455/900) were Rapid Plasma Reagin (RPR) test reactive. Of HIV positive individuals, 60.62% (n=354/584) had evidence of antibodies to T. pallidum, and of these 60.45 % (n=214/354) exhibited reactive RPR tests indicating probable (co)infection. For Bioline POCT, pooled sensitivities and specificities for HIV were 98.95% and 99.89% respectively, and for syphilis were 73.79% and 99.57%. For Chembio pooled sensitivities and specificities for HIV were 98.66% and 99.55%, and for syphilis were 78.60% and 99.48%. Both tests can detect greater than 90% of probable active syphilis cases, as defined by reactive RPR and treponemal test results. These dual POCTs were preferred by 74.77% (n=1,926) of participants, due to their convenience, and the operational characteristics made them acceptable to health care providers (HCPs).Conclusions: Both the Bioline and the Chembio dual POCT for syphilis and HIV had acceptable performance, acceptability and operational characteristics amongst MSM in the PRoSPeRo network. These dual POCTs could serve as a strategic, more cost effective, patient and healthcare provider (HCP) friendly alternative to conventional testing; in clinical and other field settings, especially those in resource-limited settings.<br/
Inflammatory biomarkers in Alzheimer's disease plasma
Plasma biomarkers for Alzheimer's disease (AD) diagnosis/stratification are a "Holy Grail" of AD research and intensively sought; however, there are no well-established plasma markers. A hypothesis-led plasma biomarker search was conducted in the context of international multicenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL; 259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed. Ten analytes showed significant intergroup differences. Logistic regression identified five (FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APOε4 adjusted, optimally differentiated AD and CTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI (AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Two analytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71). Plasma markers of inflammation and complement dysregulation support diagnosis and outcome prediction in AD and MCI. Further replication is needed before clinical translation