Affordable blood culture systems from China: in vitro evaluation for use in resource-limited settings.

BACKGROUND: Bloodstream infections (BSI) pose a significant threat due to high mortality rates and the challenges posed by antimicrobial resistance (AMR). In 2019, an estimated 4.95 million deaths were linked to bacterial AMR. The highest impact was seen in resource-limited settings (RLS). For diagnosis of BSI, performant continuously-monitoring blood culture systems (CMBCS) have been optimized. However, in RLS, the implementation of CMBCS is hindered by budget constraints and unsuitable environmental conditions. Manufacturers from growing economies are currently producing affordable in vitro diagnostics, which could fill the gap in capacity, but so far these are not established outside their domestic markets. METHODS: This study evaluated the performance, usability, and interchangeability of Chinese CMBCS in a laboratory setting using simulated blood cultures with a panel of 20 BSI-associated strains. Four systems were selected for the assessment: Autobio BC60, Mindray TDR60, Scenker Labstar50, and DL-biotech DL-60. FINDINGS: Overall, all evaluated CMBCS demonstrated good performance with high yield (96.7-100%) and specificity (97.5-100%), comparable to the reference system (bioMérieux 3D). In addition, when used as "manual" blood cultures in a conventional incubator with visual growth detection, performance was also satisfactory: yield was between 90 and 100% and specificity was 100% for all BCBs. Both the CMBCS and the BCBs were easy to use and lot-to-lot variability in BCBs was minimal. The interchangeability testing indicated that the BCBs from different brands (all except Scenker) were compatible with the various automates, further highlighting the potential for a harmonized "universal BCB." INTERPRETATION: Based on this in vitro study, we recommend the use of these systems in settings with challenging environments and limited resources. The Autobio system performed best for automatic detection and DL-Biotech BCBs for manual cultures respectively (combination of performance, price, usability). The appropriateness for use in RLS should still be confirmed in a field study. FUNDING: The study was funded by FIND.

Five accelerated schedules for the tick-borne encephalitis vaccine FSME-Immun® in last-minute travellers: an open-label, single-Centre, randomized controlled pilot trial.

BACKGROUND: The purpose of this exploratory study was to evaluate different accelerated tick-borne encephalitis (TBE) vaccine schedules for last-minute travellers. METHODS: In a single-centre, open-label pilot study, 77 TBE-naïve Belgian soldiers were randomized to one of the following five schedules with FSME-Immun®: group 1 ('classical accelerated' schedule) received one intramuscular (IM) dose at day 0 and day 14, group 2 two IM doses at day 0, group 3 two intradermal (ID) doses at day 0, group 4 two ID doses at day 0 and day 7, group 5 two ID doses at day 0 and day 14. The last dose(s) of the primary vaccination scheme were given after one year: IM (1 dose) or ID (2 doses). TBE virus neutralizing antibodies were measured in a plaque reduction neutralization test (PRNT90 and 50) at day 0, 14, 21, 28, month 3, 6, 12, and 12 + 21 days. Seropositivity was defined as neutralizing antibody titres ≥10. RESULTS: The median age was 19-19.5 years in each group. Median time-to-seropositivity up to day 28 was shortest for PRNT90 in ID-group 4 and for PRNT50 in all ID groups. Seroconversion until day 28 peaked highest for PRNT90 in ID-group 4 (79%) and for PRNT50 in ID-groups 4 and 5 (both 100%). Seropositivity after the last vaccination after 12 months was high in all groups. Previous yellow fever vaccination was reported in 16% and associated with lower GMTs of TBE-specific antibodies at all time points. The vaccine was generally well tolerated. However, mild to moderate local reactions occurred in 73-100% of ID compared to 0-38% of IM vaccinations, persistent discolouration was observed in nine ID vaccinated individuals. CONCLUSION: The accelerated two-visit ID schedules might offer a better immunological alternative to the recommended classical accelerated IM schedule but an aluminium-free vaccine would preferable.

Microsimulation Modeling in Food Policy: A Scoping Review of Methodological Aspects.

Food policies for the prevention and management of diet-related noncommunicable diseases (NCDs) have been increasingly relying on microsimulation models (MSMs) to assess effectiveness. Given the increased uptake of MSMs, this review aims to provide an overview of the characteristics of MSMs that link diets with NCDs. A comprehensive review was conducted in PubMed and Web of Knowledge. Inclusion criteria were: 1) findings from an MSM; 2) diets, foods, or nutrients as the main exposure of interest; and 3) NCDs, such as overweight/obesity, type 2 diabetes, coronary heart disease, stroke, or cancer, as the disease outcome for impact assessment. This review included information from 33 studies using MSM in analyzing diet and diverse food policies on NCDs. Hereby, most models employed stochastic, discrete-time, dynamic microsimulation techniques to calculate anticipated (cost-)effectiveness of strategies based on food pricing, food reformulation, or dietary (lifestyle) interventions. Currently available models differ in the methodology used for quantifying the effect of the dietary changes on disease, and in the method for modeling the disease incidence and mortality. However, all studies provided evidence that the models were sufficiently capturing the close-to-reality situation by justifying their choice of model parameters and validating externally their modeled disease incidence and mortality with observed or predicted event data. With the increasing use of various MSMs, between-model comparisons, facilitated by open access models and good reporting practices, would be important for judging a model's accuracy, leading to continued improvement in the methodologies for developing and applying MSMs and, subsequently, a better understanding of the results by policymakers.

Insights into the association of ACEIs/ARBs use and COVID-19 prognosis: a multistate modelling study of nationwide hospital surveillance data from Belgium.

OBJECTIVES: The widespread use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) by patients with chronic conditions raised early concerns on the potential exacerbation of COVID-19 severity and fatality. Previous studies addressing this question have used standard methods that may lead to biased estimates when analysing hospital data because of the presence of competing events and event-related dependency. We investigated the association of ACEIs/ARBs' use with COVID-19 disease outcomes using time-to-event data in a multistate setting to account for competing events and minimise bias. SETTING: Nationwide surveillance data from 119 Belgian hospitals. PARTICIPANTS: Medical records of 10 866 patients hospitalised from 14 March 2020to 14 June 2020 with a confirmed SARS-CoV-19 infection and information about ACEIs/ARBs' use. PRIMARY OUTCOME MEASURE: Multistate, multivariate Cox-Markov models were used to estimate the hazards of patients transitioning through health states from admission to discharge or death, along with transition probabilities calculated by combining the baseline cumulative hazard and regression coefficients. RESULTS: After accounting for potential confounders, there was no discernable association between ACEIs/ARBs' use and transfer to intensive care unit (ICU). Contrastingly, for patients without ICU transfer, ACEIs/ARBs' use was associated with a modest increase in recovery (HR 1.07, 95% CI 1.01 to 1.13, p=0.027) and reduction in fatality (HR 0.83, 95% CI 0.75 to 0.93, p=0.001) transitions. For patients transferred to ICU admission, no evidence of an association between ACEIs/ARBs' use and recovery (HR 1.16, 95% CI 0.97 to 1.38, p=0.098) or in-hospital death (HR 0.91, 95% CI 0.73 to 1.12, p=0.381) was observed. Male gender and older age were significantly associated with higher risk of ICU admission or death. Chronic cardiometabolic comorbidities were also associated with less recovery. CONCLUSIONS: For the first time, a multistate model was used to address magnitude and direction of the association of ACEIs/ARBs' use on COVID-19 progression. By minimising bias, this study provided a robust indication of a protective, although modest, association with recovery and survival.

Use of metformin and outcome of patients with newly diagnosed glioblastoma: Pooled analysis.

Metformin has been linked to improve survival of patients with various cancers. There is little information on survival of glioblastoma patients after use of metformin. We assessed the association between metformin use and survival in a pooled analysis of patient data from 1,731 individuals from the randomized AVAglio, CENTRIC and CORE trials. We performed multivariate Cox analyses for overall survival (OS) and progression-free survival (PFS) comparing patients' use of metformin at baseline and/or during concomitant radiochemotherapy (TMZ/RT). Further exploratory analyses investigated the effect of metformin with a history of diabetes and nonfasting glucose levels in relation to OS or PFS of glioblastoma patients. Metformin alone or in any combination was not significantly associated with OS or PFS (at baseline, hazard ratio [HR] for OS = 0.87; 95% confidence interval [CI] = 0.65-1.16; HR for PFS = 0.84; 95% CI = 0.64-1.10; during TMZ/RT HR for OS = 0.97; 95% CI = 0.68-1.38; HR for PFS = 1.02; 95% CI = 0.74-1.41). We found a statistically nonsignificant association of metformin monotherapy with glioblastoma survival at baseline (HR for OS = 0.68; 95% CI = 0.42-1.10; HR for PFS = 0.57; 95% CI = 0.36-0.91), but not during the TMZ/RT period (HR for OS = 0.90; 95% CI = 0.51-1.56; HR for PFS = 1.05; 95% CI = 0.64-1.73). Diabetes mellitus or increased nonfasting glucose levels were not associated with a difference in OS or PFS in our selected study population. Metformin did not prolong survival of patients with newly diagnosed glioblastoma in our analysis. Additional studies may identify patients with specific tumor characteristics that are associated with potential benefit from treatment with metformin, possibly due to metabolic vulnerabilities.

Temporal muscle thickness is an independent prognostic marker in patients with progressive glioblastoma: translational imaging analysis of the EORTC 26101 trial.

BACKGROUND: Temporal muscle thickness (TMT) was described as a surrogate marker of skeletal muscle mass. This study aimed to evaluate the prognostic relevance of TMT in patients with progressive glioblastoma. METHODS: TMT was analyzed on cranial MR images of 596 patients with progression of glioblastoma after radiochemotherapy enrolled in the European Organisation for Research and Treatment of Cancer 26101 trial. An optimal TMT cutoff for overall survival (OS) and progression-free survival (PFS) was defined in the training cohort (n = 260, phase II). Patients were grouped as "below" or "above" the TMT cutoff and associations with OS and PFS were tested using the Cox model adjusted for important risk factors. Findings were validated in a test cohort (n = 308, phase III). RESULTS: An optimal baseline TMT cutoff of 7.2 mm was obtained in the training cohort for both OS and PFS (area under the curve = 0.64). Univariate analyses estimated a hazard ratio (HR) of 0.54 (95% CI: 0.42, 0.70; P < 0.0001) for OS and an HR of 0.49 (95% CI: 0.38, 0.64; P < 0.0001) for PFS for the comparison of training cohort patients above versus below the TMT cutoff. Similar results were obtained in Cox models adjusted for important risk factors with relevance in the trial for OS (HR, 0.54; 95% CI: 0.41, 0.70; P < 0.0001) and PFS (HR, 0.47; 95% CI: 0.36, 0.61; P < 0.0001). Results were confirmed in the validation cohort. CONCLUSION: Reduced TMT is an independent negative prognostic parameter in patients with progressive glioblastoma and may help to facilitate patient management by supporting patient stratification for therapeutic interventions or clinical trials.

MGMT Promoter Methylation Cutoff with Safety Margin for Selecting Glioblastoma Patients into Trials Omitting Temozolomide: A Pooled Analysis of Four Clinical Trials.

PURPOSE: The methylation status of the O6-methylguanine DNA methyltransferase (MGMT) gene promoter is predictive for benefit from temozolomide in glioblastoma (GBM). A clinically optimized cutoff was sought allowing patient selection for therapy without temozolomide, while avoiding to withhold it from patients who may potentially benefit.Experimental Design: Quantitative MGMT methylation-specific PCR data were obtained for newly diagnosed patients with GBM screened or treated with standard radiotherapy and temozolomide in four randomized trials. The pooled dataset was randomly split into a training and test dataset. The unsupervised cutoff was obtained at a 50% probability to be (un)methylated. ROC analysis identified an optimal cutoff supervised by overall survival (OS). RESULTS: For 4,041 patients valid MGMT results were obtained, whereof 1,725 were randomized. The unsupervised cutoff in the training dataset was 1.27 (log2[1,000 × (MGMT+1)/ACTB]), separating unmethylated and methylated patients. The optimal supervised cutoff for unmethylated patients was -0.28 (AUC = 0.61), classifying "truly unmethylated" (≤-0.28) and "gray zone" patients (>-0.28, ≤1.27), the latter comprising approximately 10% of cases. In contrast, for patients with MGMT methylation (>1.27) more methylation was not related to better outcome. Both methylated and gray zone patients performed significantly better for OS than truly unmethylated patients [HR = 0.35, 95% confidence interval (CI), 0.27-0.45, P < 0.0001; HR = 0.58, 95% CI, 0.43-0.78, P < 0.001], validated in the test dataset. The MGMT assay was highly reproducible upon retesting of 218 paired samples (R 2 = 0.94). CONCLUSIONS: Low MGMT methylation (gray zone) may confer some sensitivity to temozolomide treatment, hence the lower safety margin should be considered for selecting patients with unmethylated GBM into trials omitting temozolomide.

Associations of anticoagulant use with outcome in newly diagnosed glioblastoma.

BACKGROUND: To test the hypothesis that despite bleeding risk, anticoagulants improve the outcome in glioblastoma because of reduced incidence of venous thromboembolic events and modulation of angiogenesis, infiltration and invasion. METHODS: We assessed survival associations of anticoagulant use from baseline up to the start of temozolomide chemoradiotherapy (TMZ/RT) (period I) and from there to the start of maintenance TMZ chemotherapy (period II) by pooling data of three randomised clinical trials in newly diagnosed glioblastoma including 1273 patients. Progression-free survival (PFS) and overall survival (OS) were compared between patients with anticoagulant use versus no use; therapeutic versus prophylactic versus no use; different durations of anticoagulant use versus no use; anticoagulant use versus use of anti-platelet agents versus neither anticoagulant nor anti-platelet agent use. Cox regression models were stratified by trial and adjusted for baseline prognostic factors. RESULTS: Anticoagulant use was documented in 75 patients (5.9%) in period I and in 104 patients (10.2%) in period II. Anticoagulant use during period II, but not period I, was associated with inferior OS than no use on multivariate analysis (p = 0.001, hazard ratio [HR] = 1.52, 95% confidence interval [CI]: 1.18-1.95). No decrease in OS became apparent when only patients with prophylactic anticoagulant use were considered. No survival association was established for anti-platelet agent use. CONCLUSIONS: Anticoagulant use was not associated with improved OS. Anticoagulants may not exert relevant anti-tumour properties in glioblastoma.