bluuebunny/crossref_metadata_2025_split huggingface dataset:
A-078 Accuracy Based Sigma Metrics of Alinity c System as Benchmarked against Roche c701
Authors: Cheng L , Guan Q , Li H , Miao J , Sun P , Chen C 
Published: September 2023

Abstract

Background
Assay performance is dependent on the accuracy and precision of a given method. Sigma metric is a well-established tool for objectively assessing such performances. The objective of the study is to evaluate the Alinity c system using a representative set of clinical chemistry assays in an independent central laboratory setting. The analytical performance of the Alinity c assays was compared with the Roche c701 assays using accuracy-based Sigma metrics.

Methods
Analytical performance of 7 clinical chemistry assays, including sodium, potassium, chloride (Integrated Chip Technology or ICT), Glucose, ALT, AST and creatine kinase (CK), was assessed on the Alinity c System as benchmarked against the Roche c701. The accuracy of the assays was evaluated by testing reference standard materials sourced from Reference Material Institute for Clinical Chemistry Standards (ReCCS)) in Japan or National Institute of Standards and Technology (NIST) in America. The 5-day precision evaluation per CLSI EP15-A3 was performed using the Bio-Rad Lyphochek® Assayed Chemistry Control and two patient sample pools. Linearity was assessed using 9 levels of patient sample pools covering the measuring interval of each assay. Method comparison with Roche c701 assays was performed per CLSI EP9-A3 using 60 patient samples spanning the measurement range. Sigma metrics for each assay were determined relative to the total allowable errors according to the Clinical Laboratory Improvement Amendments (CLIA) specifications.

Results
Within-lab (total) imprecision for the 7 assays on Alinity c and Roche were all &lt;3.5% CV for both the Bio-Rad Control and patient pools. Alinity c assays showed a better precision performance in all of assays tested. Bias of the 7 assays in reference to the assigned values was all below 7.5% for both platforms. Alinity c exhibited a good correlation with Roche c701 on all 7 assays in the method comparison evaluation. Linearity of the Alinity c assays was validated for the measuring intervals as claimed by the manufacturer. Majority of the assays on both analzyers demonstrated at least 6 sigma performance with Alinity c showing better sigma scores.

Conclusion
The Alinity c System demonstrated excellent accuracy, precision and linearity in an evaluation of 7 clinical chemistry assays. A majority of the assays demonstrated at least 6 sigma performance, supporting the fitness for clinical use.
A-096 Novel Gastrointestinal Testing: Comparative Performance of the ALPCO Five-Plex Gastrointestinal Marker Assay compared to Conventional ELISA/CLIA testing for Human Stool Samples
Authors: Cacicedo J M , Papkov S , Petzke J , Schmidt W , Vedrani H , Veenstra K , Wisherd C 
Published: September 2023

Abstract

Background
All modern gastrointestinal (GI) testing laboratories face a similar challenge: How to test a panel of analytes from the same stool or plasma/serum sample and deliver clinically accurate results in a timely fashion. GI analytes are tested primarily on ELISAs that while accurate, manual ELISA testing is time-consuming and work intensive. In this study, we utilize the automated ALPCO five-plex assay (AutoPlex™) to measure five key GI biomarkers: Calprotectin (CP), Pancreatic Elastase (PE), Lactoferrin (LF), Eosinophil derived neurotoxin (EDN), and Hemoglobin (Hgb). These biomarkers are widely recognized indicators of gut inflammation and disease, including inflammatory bowel disease, pancreatic insufficiency, and colorectal cancer. The assay employs a simple and efficient sample preparation protocol and utilizes multiplexed bead-based technology to quantify each biomarker at the same dilution and time point in an automated fashion. In this study, we determine how this new assay performs against gold standard ELISA/CLIAs that measure the same analytes.

Methods
Capture and detector antibodies were optimized for each of the analytes to perform on beads, and buffers were optimized to allow for all the analytes to be measured simultaneously. A stool extraction device was utilized to extract 386 human stool samples from both healthy controls and populations with suspected GI impairment. Samples were analyzed using the ALPCO 5-Plex (AutoPlex) assay run on the Multiplier® - a fully-automated chemiluminescence analyzer (DYNEX® Technologies, Chantilly, VA), and conventional Chemiluminescence ELISA/CLIA methods.

Results
Comparative analysis of 386 human stool samples run on both the 5-Plex and ELISAs for each respective analyte, showed strong clinical correlation between the two platforms. With a clinical cut-off of 50 ug/g calprotectin had a 91% clinical correlation between the two platforms. Similarly, with a cut-off of 200 µg/g PE was at 91%, LF with a cut-off of 7.24 µg/g at 83%, EDN with a cut-off of 4.6 was at 97%, and Hgb with a cut-off of 20 µg/g was at 98% clinical correlation between the two platforms.

Conclusions
The results generated by ALPCO five-plex assay demonstrated on average &gt;90% clinical matching for all 5 GI analytes tested when compared to their gold standard ELISA/CLIA counterparts. Since this assay allows for the simultaneous measurement of five common GI analytes that occur from a single stool extract in one concurrent and automated workflow, this saves time as it eliminates the need for multiple ELISA/CLIA tests and reduces processing time for stool samples.
A-097 Stability Study of 21 Common Plasma Biochemistries in Unspun Whole Blood
Authors: Ospina Romero M , Robakowski T , Nelson A , Grant K , Jin Z , Galior K 
Published: September 2023

Abstract

Background
Most blood collection tube manufacturers typically recommend separating serum/plasma from red blood cells within 2 h of collection prior to biochemical analysis to minimize cell contact and thus maintain stability of analytes. This can lead to rejected testing when uncentrifuged samples are transported from ambulatory sites to core laboratories over long distances, leading to delayed patient care and decreased patient satisfaction from having to be redrawn. Few studies are available to make recommendations of specimen acceptance with delayed centrifugation time. Our study aimed to assess whole blood stability of routinely ordered chemistry tests.

Methods
Between November 30–December 1, 2022, venous blood from 20 non-fasting healthy adults(30% male) with ages ranging from 23 to 57 years were collected into 3-mL plastic Becton Dickinson(BD) Vacutainer™plasma separated tubes(PST). For each person, 6 PST were collected. One whole blood sample was centrifuged immediately(T0) at 4000g for 3 min at room temperature(RT) and analyzed. Remaining 5 whole blood samples were stored at either RT or 4 °C and the subsequent centrifugation of the samples occurred at 2, 4, 6, 12 and 24 h after collection. The analytes studied using Abbott Alinity instrumentation were comprehensive metabolic panel(CMP), lipid panel, TSH and FT4. Absolute and percent bias at various time points for each participant were calculated using the reference sample(T0). Observed biases were compared to allowable total error based on desirable biological variation(BV) from European-Federation-of-Laboratory-Medicine(EFLM) database and Clinical-Laboratory-Improvement-Amendments(CLIA) 2024 upcoming limits.

Results
Analytes stable in the whole blood at both RT and 4 °C up to 24 h based on EFLM-BV and CLIA were ALP, ALT, AST, BUN, cholesterol, creatinine, HDL, total bilirubin, triglycerides, and TSH. Analytes with variable stability times are shown in the table below:

Conclusion
This study provides a guideline of acceptable times for whole blood samples sent for routine chemistry tests when centrifugation was not performed within 2 h from collection.
A-128 Analytical Performance Evaluation of Assays Used for Iron Studies on the Atellica® CI 1900 Analyzer
Authors: Freeman J , Kolewe K , Singh S , Valdivia B , Varhue W , Arrode-Bruses G , Rhea-McManus J , Snyder J , Leipold H 
Published: September 2023

Abstract

Background
The Atellica® CI 1900 Analyzer is an automated, mid-throughput, integrated chemistry and immunoassay analyzer employing both Atellica CH and Atellica IM assays. This study was designed to evaluate the analytical performance of the Atellica CH Iron_2 (Iron_2), Total Iron Binding Capacity (TIBC), and Transferrin (Trf) assays* and the Atellica IM Ferritin (Fer) assay on the Atellica CI 1900 Analyzer.

Methods
The Atellica CI 1900 Iron_2, TIBC, and Trf assays use the same reagents and calibrators as the comparable Atellica chemistry assays. The Atellica CI 1900 Fer assay uses the same reagents and calibrators as the Atellica immunoassay. Precision and method comparison (MC) were used as performance indicators for the Atellica CI 1900 Analyzer. Precision studies were performed according to CLSI EP05-A3 using native and contrived human serum samples. MC studies were performed according to CLSI EP09-A3. Native and contrived human samples were analyzed using the Atellica CH Iron_2, TIBC, and Trf assays on both the Atellica® CH 930 and Atellica CI 1900 Analyzers. For Fer, native and contrived human samples were analyzed using the Atellica IM Fer assay on both the Atellica® IM 1600 and Atellica CI 1900 Analyzers.

Results
Representative precision and MC results for each assay are listed in the table. For the four assays tested, repeatability and within-lab %CVs were &lt;3.5% and &lt;4.5%, respectively. Slopes determined by the Deming linear regression model were approximately equal to 1.

Conclusion
Evaluation of the Atellica CH Iron_2, TIBC, and Trf and Atellica IM Fer assays using the Atellica CI 1900 Analyzer demonstrated good precision and equivalent performance compared to the same assays on their respective Atellica CH 930 and Atellica IM 1600 Analyzers.
*The products mentioned are not commercially available in all countries. Their future availability cannot be guaranteed.
A-134 Correlation Study of Haematology Analyser Sysmex XS 1000 vs Beckman DXH 520
Authors: Teng J 
Published: September 2023

Abstract

Background
An evaluation was conducted on 2 different haematology analysers to determine its result correlation. Both Sysmex XS1000i and Beckman DXH 520 are 5 part differential count analysers.

Methods
The evaluation was conducted on Sysmex XS 1000 and 2 units of Beckman DXH 520 at NHGD YIS lab in 2020. All instruments underwent precision study, carryover test and linearity to ascertain its performance prior to the concordance study.63 samples were used in the correlation all reportable parameters and WBC differential count and its flagging.

Results
The 2 units of DXH 520 demonstrated acceptable performance in precision, carryover and Linearity. The correlation of the parameters were within RCPA allowable error. However, we noted a low concordance of 39% in the WBC differential count flagging. To validate the flagging, manual differential count was conducted.

Conclusion
During the correlation, Sysmex XS appeared to be more sensitive to Atypical lymphocytes where manual differential count read &lt;5%. This inevitably resulted in more manual slide review. In the 63 samples, 4 cases with high atypical lymphocytes (&gt;5%) seen in manual differential count and they were flagged as lymphocytes in sysmex XS1000i and as monocytes in DxH 520. To counter the potential missed out in the reporting of Atypical lymphocytes in DXH, a lower threshold for monocytes in slide review may be needed.
A-216 Measuring Inflammation and Cardiovascular Markers at Benchtop NMR using Diffusion and Relaxation Edited Experiments
Authors: Wist J , Nitschke P , Masuda R , Lodge S , Schaefer H , Cannet C , Holmes E , Nicholson J K 
Published: September 2023

Abstract

Background
Metabolic phenotyping is an established tool in systems medicine that captures a profile of one’s individual health status and reflects the interaction between genes and external stressors. It uses analytical platforms such as NMR or MS to acquire molecular profiles, and modelling to extract actionable knowledge. Applying these techniques to a cohort of Australians infected by SARS-CoV-2 revealed a strong alteration in regions of 1D NMR spectra associated with lipoproteins and glycoproteins, and referred as Supramolecular Phospholipid Composite SPC (δ = 3.2 ppm) and Glyc (δ = 2.07 ppm). The latter is an established marker of inflammation. These results were later confirmed using larger cohorts from Spain (n = 525) and the UK (n = 1022). The urgent need for very rapid testing, at the early stage of the pandemic, prompted the development of bespoke NMR experiments able to measure this lipoproteins/glycoproteins signature without requiring complex modelling.

Methods
Physico-chemical properties of lipoprotein particles, such as diffusion, transverse and longitudinal relaxation rates, differ from low molecular weight metabolites. Therefore, an edited experiment JEDI (PGPE) was designed that combines diffusion, relaxation and scalar coupling editing blocks to produce a lipoprotein profile devoid of chemical noise (overlapping peaks) and where peaks give quantitative results.

Results
The SPC peak was further broken down into 3 sub-regions that are related to the main subfraction HDL and LDL (choline headgroups of phospholipids). Interestingly the ratio of SPC3/SPC2 highly correlates with the Apo-B100/Apo-A1 ratio, an established cardiovascular risk marker that is increased in patients with COVID19. Longitudinal data suggest this latter remains elevated even 30 days after onset in some patients. Furthermore, the edited experiment performs equally well at low field using a benchtop NMR.

Conclusion
Translation of a spectral signature relevant for monitoring COVID patients from high to low field NMR is possible using sophisticated editing techniques.
A-221 Evaluation of Apolipoprotein B Equivalent Low-density Lipoprotein Cholesterol Measurements
Authors: Hornseth J M , Donato L J , Jaffe A S , Meeusen J W 
Published: September 2023

Abstract

Background
Low-density lipoprotein cholesterol (LDL-C) is the primary biomarker for assessing risk for atherosclerotic cardiovascular disease (ASCVD). However, multiple large studies have demonstrated greater accuracy using Apolipoprotein B (apoB). One obstacle to its widespread use is the lack of guideline endorsed apoB treatment targets. A recently published solution has proposed using population percentiles to calculate LDL-C using apoB values (PMID: 36366949). The LDL-C concentration correlated to an individual’s ApoB percentile may more appropriately reflect ASCVD risk compared to lipid panel LDL-C. Here we evaluated this approach using a cohort where LDL-C was measured with the gold-standard beta-quantification method (LDL-CBQ).

Method
Results from clinically ordered apoB, LDL-CBQ, and lipid panel were included (n = 18 852). Samples with triglycerides &gt;1000 mg/dL or LpX were excluded. Total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and apoB were measured using Roche Cobas c501 analyzers. LDL-CBQ was performed using Beckman LE-80K ultracentrifuge and dextran sulfate-Mg/Cl precipitation. ApoB equivalent LDL-C (eqLDL-CapoB) was calculated according to linear regression of LDL-C percentiles against apoB percentiles described by the equation eqLDL-CapoB = 1.45(apoB)-25. Concordance was determined based on clinical thresholds for LDL-CBQ and eqLDL-CapoB.

Results
Median (IQR) apoB and LDL-CBQ was 98 (79−119) mg/dL and 120 (94−150) mg/dL, respectively. LDL-CBQ and eqLDL-CapoB were concordant in 60% of samples overall.
Discordance between eqLDL-CapoB and LDL-CBQ shifted from primarily overestimating to underestimating as LDL-CBQ increased. Discordant eqLDL-CapoB was directly associated with TG and inversely associated with HDL-C.

Conclusion
The eqLDL-CapoB calculation is a useful tool to present apoB results in a more familiar context of LDL-C-equivalent units. The concordance findings largely confirm previously published results using eqLDL-CapoB. Furthermore, the pattern of HDL-C and TG suggests that a discordantly elevated eqLDL-CapoB is an indicator of a higher risk lipid profile. More investigation is needed to determine if eqLDL-CapoB is appropriate for widespread adoption.
A-239 Comparison Between Blood Culture and MeMed BV Test Results
Authors: Zuretti A , Christian M , Motov S , Kogan M 
Published: September 2023

Abstract

Background
The rate of cultures ordered for patients in which infection is suspected is approximately 40% on Emergency Department patients at Maimonides Medical Center and represents a significant financial burden for our institution. Most blood cultures in clinical practice do not grow organisms suggesting that suboptimal blood culture collection practices (e.g., suboptimal blood volume) or suboptimal selection of patients to culture (patients with low likelihood of bacteremia may be occurring.
•BV is a new host-protein test based on TRAIL, TNF-related apoptosis inducing ligand protein, IP-10, interferon gamma -induced protein 10 and CRP, C- reactive protein that produces a score between 1–100 indicating the likelihood of a bacterial vs viral infection. It has been validated in multiple studies to have sensitivity and specificity of more than 90%.• In this study we compare blood culture and BV results.

Methods
BV test were taken at ED physician discretion from March 2022 to December 2022
• BV score 0–35 is viral, 35–65 is equivocal and 65–100 is bacterial.
• BV test was measured using MeMed BV (MeMed, Israel) and MeMed Key (MeMed, Israel) from serum samples.
• This sub analysis focuses on patients presenting at the ED for whom blood culture was ordered and there was a record of the result.

Results
• BV test was taken for 545 patients during their ED visit, of these, 389 had blood cultures drawn and results recorded.
• There were 233 cases with BV score bacterial, 42 with BV score equivocal and 114 with BV score viral
• Out of the BV score viral, there were 7 with positive findings, of which 5 were considered contaminants

Conclusion
There is a high agreement between viral BV results and negative cultures. Ongoing collection of this data in real time will help establish this finding further in order to provide guidance for our clinicians to reduce the financial burden of unwarranted cultures as well as the unnecessary administration of antibiotics.
A-302 Agreement Assessment Between Molecular and Rapid Tests in Respiratory Viruses Detection
Authors: Martins L A , Domingues R S , Silva J D , Zauli D A , de Lima A B 
Published: September 2023

Abstract

Background
Diseases caused by respiratory viruses are the most frequent diseases in humans and have a significant impact on morbidity and mortality worldwide. Due to their transmission nature, these viruses are able to widespread dissemination. The pandemic caused by COVID-19 highlights this potential, however, other respiratory viruses also continue to circulate such as Respiratory Syncytial Virus (RSV) and Influenza (FLU). Efficient diagnostic tools are necessary, especially in endemic regions. Although molecular tests are gold standards, rapid tests (RTs) represent a great alternative once they are more accessible, faster, easier to manage, and can be performed at the point of care. Therefore, this work aimed to evaluate the analytical performance of RTs compared to molecular tests in the detection of viral antigens of RSV or FLU in swab samples.

Methods
Swab samples in saline solution (n = 60) were tested by qPCR molecular assay Multiplex Alinity m Resp-4-Plex Assay (Abbott Molecular) and RTs immunofluorescence-based (ECO-F RSV ag and ECO-F Influenza A/B—ECO Diagnostica). For the molecular assay, samples were prepared according to the manufacturer's instructions. For RTs, samples were submitted to the extraction buffer, incubated for 10 or 15 minutes respectively, and analyzed by ECO Reader F200 equipment, according to the manufacturer's instructions. It uses a cut-off value ≥1.00 for positive samples and &lt;1.00 for negative samples.

Results
All negative samples (RSV = 20; FLU = 20) in molecular test were concordant with RTs results. The number of positive samples detected by molecular test was 4 and 16 for FLU and RSV respectively, while RTs detected a lower number of positive samples (FLU = 2; RSV = 10). Both RTs achieved a specificity of 100%; sensibility was 62, 50% for RSV and 50% for FLU. Using Cohen's Kappa index to assess the agreement between the compared tests, it was obtained the expected and observed values of 0.83 and 0.53 for RSV and 0.92 and 0.78 for FLU, which represents an index of 0.649 and 0.625 respectively. These results indicate substantial agreement between the tests, although the sensitivity of the molecular assay was superior.

Conclusion
Molecular tests can be used to confirm the results of RTs, once they are the gold standard for diagnosis. However, they have a high operational cost, which makes RTs a good alternative to help in the screening of these respiratory diseases, especially in resource-limited settings, allowing effective treatment and management for the patient.
A-309 Challeging Diagnostic of Neurosyphilis: Use of CXCL13 Concentration in Cerebrospinal Fluid
Authors: Carvalho R D , Rangel I D , Bacarov N B , Soane M M , Herbst V , Ferry F D 
Published: September 2023

Abstract

Background
Previous retrospective has been demonstrated the concentration of chemokine ligand CXCL13 in cerebrospinal fluid (CSF-CXCL13) is a promising biomarker in the diagnosis of neurosyphilis (NS) and monitoring of therapeutic efficacy. The goal of this study was to measure CXCL13 concentrations in CSF of NS suspected patients and compare with patients with syphilis non-NS and patients with treated syphilis.

Methods
One hundred and eleven NS-suspected participants from Rio de Janeiro (Brazil) were investigated for the detection of IgG antibodies against Treponema pallidum, using ELISA and Indirect Immunofluorescence tests (EUROIMMUN, Lübeck, Germany). CSF-CXCL13 concentration was prospectively performed by ELISA (EUROIMMUN, Lübeck, Germany) assay in all participants at baseline and in participants diagnosed with NS in follow-up visits at 3, 6, and 12 months after therapy.

Results
CSF-CXCL13 concentrations were significantly higher in patients with established NS presenting a median concentration of 207.4 pg/mL (IQR 69.3–1515.5 pg/mL) than in patients with syphilis non-NS with a median of 1.0 pg/mL (IQR 0.1–11.0 pg/mL, P &lt; 0.001) or patients with treated syphilis with a median of 0.1 pg/mL (IQR 0.1–7.1 pg/mL, P &lt; 0.001). The CSF-CXCL13 concentrations decreased after 3, 6 and 12 months of therapy compared to baseline in all cases of NS. The added concentration of CSF-CXCL13 above 62.8 pg/mL plus CSF-FTA-ABS reactivity agreed with diagnosis of NS in 88.9% of People Living with HIV (PLWHs) and plus CSF-TPHA reactivity agreed with the diagnosis of NS in 100% of HIV-uninfected patients.

Conclusion
The study suggests that the clinical use of CSF-CXCL13 is useful for supplementary biomarker for NS and as monitoring the effectiveness of NS therapy, especially in PLWHs with nonreactive CSF-VDRL, excluded other neurologic diseases.