bluuebunny/crossref_metadata_2025_split huggingface dataset:
A-329 Accuracy of the pH, PO2, and PCO2 Tests in the i-STAT® G3+ Cartridge Using the i-STAT 1 System for Venous, Arterial and Capillary Whole Blood Specimens in Clinical Settings
Authors: Kornfeld S F , Gonzalez Aguirre M , Mohammed A , Kovacevic S , Zhang H , Gupta M 
Published: October 2024

Abstract

Background
Precise and accurate measurements of blood gases are important for the diagnosis, monitoring and treatment of respiratory, metabolic, and acid-base disturbances. This study demonstrates the accuracy of the pH, partial pressure of oxygen (PO2), and partial pressure of carbon dioxide (PCO2) tests in the i-STAT G3+ cartridge with the i-STAT 1 System in arterial, venous, and capillary whole blood specimens in point of care or clinical laboratory settings.

Methods
The accuracy of the PO2, and PCO2 tests in the i-STAT G3+ cartridge was assessed at external clinical sites in a method comparison study using whole blood specimens across the measurement range for each test: pH 6.5-7.8, PO2 5-700 mmHg, PCO2 5.0-130.0 mmHg. Specimens used in this study were venous, arterial, and capillary specimens prospectively collected under Institutional Review Board-approved informed consent or were leftover de-identified venous or arterial specimens. The study included venous and arterial whole blood samples from ∼140 adult subjects (≥ 18 years) at 3 clinical sites, and capillary whole blood samples from ∼180 adult subject at 3 clinicals sites and ∼25 neonate subjects (birth to 28 days) at 2 clinical sites. The RapidPoint System was used as comparator. For venous and arterial whole blood, samples were collected and tested in duplicate on the i-STAT G3+ cartridge and in singlicate on the RapidPoint System. For capillary whole blood samples, adult fingerstick samples and neonate heel-stick samples were collected in capillary tubes and tested in singlicate on the i-STAT G3+ cartridge and on the RapidPoint System. Passing-Bablok regression was performed for venous and arterial whole blood samples combined, using the first replicate from the i-STAT G3+ cartridge versus the singlicate result from the comparator, and for capillary whole blood samples (adult and neonate combined) using the singlicate result from the i-STAT G3+ cartridge versus the singlicate result from the comparator.

Results
Passing-Bablok regression of i-STAT G3+ cartridge results versus the comparator was used to calculate slope and correlation coefficient (r). For adult venous and arterial whole blood results, pH had slope = 0.96 and r = 0.99, PO2 had slope = 1.05 and r = 1.00, and PCO2 had slope = 1.04 and r = 0.98. For adult and neonate capillary whole blood results, pH had slope = 1.02 and r = 0.98, PO2 had slope = 1.09 and r = 0.99, and PCO2 had slope = 1.07 and r = 0.96.

Conclusions
These results demonstrate that the i-STAT 1 System delivers accurate pH, PO2, and PCO2 test results with ∼2 minutes using the i-STAT G3+ cartridge for venous, arterial and capillary whole blood samples for adult and neonate subjects when tested by end-users in a point of care or clinical laboratory setting. This study was funded by Abbott Laboratories.
B-033 Real World Assessment of the Impact of Infectious Disease Assays on Workflow Capabilities of Siemens Atellica IM Analyzers
Authors: Abou-Diwan C , Hempton R , Clouet J , Diabate D , Aguanno J 
Published: October 2024

Abstract

Background
Instrument immunoassay throughputs publicized in the industry are often theoretical, performed in relatively smaller scale, and/or in the best case generated only with fast assays, not representing the typical assay mix of routine activity. Infectious disease (ID) serology assays typically have long analytical times and have the potential to influence throughput capabilities and turnaround time (TAT) of other assays with shorter analytical times. The objective of this study is to utilize real world evidence across a large fleet of Atellica® IM 1300 and IM 1600 analyzers representing variously sized laboratories, using variations of ID assay mixes, to assess the impact on TAT on select STAT immunoassays.

Methods
Assay mix, test volumes and TAT data was mined from the Atellica® Smart Remote Services (SRS), a Siemens Healthineers proprietary remote connectivity platform over 3 distinct 14-day time windows. Real world data from &gt;1800 Atellica IM and &gt;8 million tests were queried per time window for the following ID assays: HIV, Hepatitis B, Hepatitis C, TORCH, Syphilis (long analytical time) and a selection of non-ID immunoassays: hs-troponin I (TNIH), Thyroid Stimulating Hormone (TSH3UL), total HCG (ThCG), and B-Type Natriuretic Peptide (BNP) (short analytical time). Median TAT for short assay was analyzed with 6 variations of ID assay mix (0%, &lt;10%, &lt;20%, &lt;30%, &lt;40%, &lt;50%) in the run representing increasing percentages of assays requiring longer incubation times. TAT was represented as barcode to result and aspiration to result.

Results
The median TAT for TNIH remained consistent at 10.1 minutes across increasing % of ID assays (N=100961). The median TAT for TNIH for platforms not running ID assays (83237) remained consistent at 10.03 minutes. The median TAT for TSH remained consistent at 14.02 minutes across increasing % of ID assays (N=1183344). The median TAT for TSH for platforms not running ID assays (N=480219) remained consistent at 13.98 minutes. The median TAT for ThCG remained consistent at 10.28 minutes across increasing % of ID assays (N=24677). The median TAT for ThCG for platforms not running ID assays (N=79275) remained consistent at 10.27 minutes. The median TAT for BNP remained consistent at 10.1 minutes across increasing % of ID assays (N=42949). The median TAT for BNP for platforms not running ID assays (N=14990) remained consistent at 10.03 minutes.

Conclusions
Throughput and TAT on the Atellica IM Analyzer is relatively unaffected by mix of longer-incubation and shorter-incubation assays. The dual incubation rings allow more flexibility in the mix of incubation times with predictable and consistent TAT for all assays including STAT.
B-050 A comparison of two semi-quantitative tests, Abbott’s Advise DX SARS-CoV-2 IgG II and Beckman Coulter’s Access SARS-COV-2 IgG II, for measuring IgG antibody levels after Sars-CoV-2 Pfizer-BioNTech vaccination
Authors: Niklinski W , Niklinska E , Siddiqui S , Ferrer Peace D 
Published: October 2024

Abstract

Background
Using 219 samples collected from volunteer employees of our lab, obtained in different times after Sars-CoV-2 Pfizer-BioNTech vaccination, we compared two semi-quantitative tests:

Methods
Abbott's AdviseDx SARS-CoV-2 IgG II and Beckman Coulter’s Access SARS-CoV-2 IgG II assay. Both assays detect IgG antibodies to the receptor binding domain of the S1 subunit of the spike protein of SARS-CoV-2 in serum and plasma of tested individuals. For the Beckman test, AMR is from 0 to 450 AU/ml with cut off for positive test 10 AU/ml; for the Abbott test, AMR is from 0 to 25000 AU/ml with cut off for positive test 100 AU/ml.

Results
Using a fitted regression line, it appears that the best correlation between these two tests was found in the lower value range, below 25AU/ml for Beckman test and 4000 AU/ml for Abbott test (R-squared value of 0.842 and y=87.165x). For higher antibody levels, the result distribution resembles a binary pattern, which we find very interesting. We will discuss possible explanations of this finding.

Conclusions
B-065 Comparative Analysis of 14-3-3η Autoantibody Assays on Luminex Platform for Diagnosing Axial Spondyloarthritis
Authors: Sidhu N , Maksymowych W P , Wichuk S , Marotta A 
Published: October 2024

Abstract

Background
The pathophysiological significance of extracellular 14-3-3η antigen and its autoantibodies (AAbs) is well-documented in autoimmune rheumatologic disorders. Use of 14-3-3η protein blood tests is common in diagnosing and managing rheumatoid arthritis (RA). Prior studies have established the diagnostic and prognostic value of 14-3-3η AAbs in RA and axial spondyloarthritis (AS), particularly in differentiating AS patients from healthy individuals and in relation to disease severity and progression. This study explores the performance of a novel assay platform in the context of AS diagnosis, especially in younger patients who are most responsive to early treatment interventions.This research aims to evaluate the discriminative accuracy of the 14-3-3η AAb assay on the Luminex® platform, a widely recognized clinical tool, in distinguishing AS patients from healthy subjects, and to compare its performance with that of the Meso Scale Discovery® (MSD) research-use only (RUO) platform.

Methods
Sera from 49 AS patients and 25 healthy controls (HC), previously assessed using the MSD platform, were reanalyzed using a new Luminex 14-3-3η AAb assay. These samples were sourced from the Follow Up Research Cohort in Axial Spondyloarthritis (FORCAST) Prognostic Cohort. Spearman correlations were employed for variable analysis, and the Mann-Whitney U-test was used to compare AAb levels between groups. Receiver Operating Characteristic (ROC) Area Under Curve (AUC) analyses were conducted for both assay platforms, with a specific focus on patients aged 45 and under.

Results
The AS patient group had a mean age (SD) of 44 (13) years, with 67% male representation. The median (IQR) disease duration was 19 (10-24) years, and median (IQR) C-reactive protein (CRP) levels were 9.6 (4.3 - 24.8) mg/L. Median (IQR) 14-3-3η AAb levels were significantly higher in AS patients at 136 U/μl (48 - 408) compared to HCs at 54 (28 - 161) U/μl, p=0.02. ROC AUC analysis for the MSD RUO platform showed an AUC of 0.67 (95% CI, 0.55 - 0.79), and for the Luminex platform, an AUC of 0.66 (95% CI, 0.53 - 0.80), indicating comparable performance across platforms. In the subgroup of AS patients aged ≤45 years, the Luminex assay demonstrated an AUC of 0.74 (95% CI, 0.61-0.88), p=0.003. Combination of 14-3-3η AAbs and CRP was able to identify 90% of AS patients. No correlation between the two markers was observed (r= -0.14, p=0.38).

Conclusions
The Luminex-based 14-3-3η AAb assay exhibits equivalent discriminative capability to the MSD RUO assay in differentiating AS patients from healthy individuals. The combined use of 14-3-3η AAbs and CRP, identifying 90% of AS patients, highlights the potential of these biomarkers as complementary diagnostic and prognostic tools in AS, meriting further research.
B-070 Supar: what UACR and GFR don't say…
Authors: Valaperta S , Gamba S , Leo C , Moioli V , Saiaci C , Marozzi R , Alessio M 
Published: October 2024

Abstract

Background
Soluble urokinase-type plasminogen activator receptor (suPAR) is the circulating form of a three domain membrane protein expressed on a variety of cells, including immunologically active cells, endothelial cells, and podocytes. Diabetic nephropathy (DN) typically manifests with impaired glomerular filtration and microalbuminuria and progresses to end-stage renal disease. The study investigated whether high levels of suPAR may be added to KDIGO models that includes estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR) to give more information about diabetic patients at higher risk of DN occurrence.

Methods
We measured plasma suPAR levels in 142 patients (67F/75M, median age 67 years) admitted to our hospital to check their glucose and glycated A1c hemoglobin (HbA1c) levels. We also recorded information about UACR and eGFR, and the relationship between suPAR levels and these parameters was investigated together with the distribution of suPAR levels according to KDIGO category risk of CKD.

Results
Among our study population, according to KDIGO risk category, 80 patients were at low risk, 47 were at moderate risk and 13 were at high risk of CKD. Mean plasma suPAR levels are 4.613±3.331 ng/mL, and significant correlation between suPAR and eGFR (P=0.0001) and between suPAR and HbA1c (P=0.0026) were found, while there is not a significant correlation with UACR (p=0.207) . According to KDIGO category risk, suPAR levels significantly increased from low to high risk, in particular, the increase is higher between the first two category (4.176 vs 6.285 ng/mL) risk compared to the highest (7.557 vs 7.427 ng/mL). We classified the 80 patients at low risk for KDIGO according suPAR levels divided into 4 quartiles according to literature (S. Salim Hayek et Al 2015) and 52 of them had suPAR levels in the third and fourth quartiles. Moreover, among these 52 patients, only 5 had HbA1c levels over the therapeutic target of 53 mmol/mol.

Conclusions
We identified an association between elevated plasma suPAR levels and a decline in the eGFR. However, we did not find a correlation with UACR, this is because suPAR levels are associated with a prospective membrane damage through interference with podocyte migration and apoptosis. According to this analysis, suPAR is a possible best candidate marker to stratify those patients who, according to the KDIGO criteria, are at low risk and have good glycemic compensation, but suPAR levels suggest a more careful follow-up.
B-072 Analytical Evaluation of a Novel Fully Automated Multiplexed Microarray Immunoassay for the Simultaneous Detection of Eleven Autoantibodies Associated with Connective Tissue Diseases in a Spanish Reference Laboratory
Authors: Gomez G , Pérez-Artes R , Fischer C , Viñas-Giménez L , Sanz-Martínez M 
Published: October 2024

Abstract

Background
Detection of different autoantibodies is key in the identification of autoimmune diseases; however, most available devices are either individual tests and/or manual/semi-automated. Development of fully-automated multiplexed devices for autoantibody testing is needed. We evaluated the analytical performance of the novel MosaiQ® AiPlex CTD (AiPlex-CTD) microarray, used with the fully-automated MosaiQ system, for simultaneous qualitative detection of eleven autoantibodies associated with connective tissue diseases (CTD), compared with selected CE-marked devices.

Methods
AiPlex-CTD microarrays (AliveDx, Switzerland) were prepared by printing antigens onto functionalized glass chips. Microarrays consisting of 2 separate sides (1 side was printed, leaving the other side available for future addition of antigens) were assembled into magazines (containing 250 microarrays) for processing on the MosaiQ 125 instrument. Serum samples from a Spanish refence laboratory, characterized as reactive to ≥1 autoantibodies using Quanta Flash® CTD Screen (Werfen, Spain) or as non-reactive by FIDISTM Connective Profile (Theradiag, France). All samples were tested with AiPlex-CTD. Positive percent agreement (PPA) and negative percent agreement (NPA), overall and for individual analytes were calculated.

Results
Compared with Quanta Flash® CTD Screen, AiPlex-CTD showed PPA ranging from 80% for Sm to 100% for SS-A 60, TRIM21, U1RNP, Jo-1 and Scl-70. No reactive samples were available for Sm/RNP and Ribosomal P. Compared with FIDIS, NPA ranged from 95% for dsDNA, Scl-70 and CENP-B and 100% for SS-A 60, TRIM21, SS-B, Sm, Sm/RNP, U1RNP, Jo-1 and Ribosomal P. Performance details for individual analytes are shown in the Table.

Conclusions
In this sample cohort, AiPlex-CTD demonstrated high concordance with the compared CE-marked devices for the automated qualitative detection of the autoantibodies included in the assay, which is line with previous observations in a larger cohort using FIDIS and other CE-marked devices. This high throughput multiplexed platform has the potential to help optimize CTD testing by simplifying complex testing pathways.
B-074 Comparative Evaluation of Clinical Utility between Indirect Immunofluorescence and Immunoassay Methods for Antineutrophil Cytopalsmic Antibody Detection
Authors: Jeon S , Park J , Choi H , Nah E , Choi H , Kee S 
Published: October 2024

Abstract

Background
ANCA testing is essential for the diagnosis of vasculitis, commonly using indirect immunofluorescence(IIF) and immunoassay(IA) methods. Recent guidelines recommend IA as the primary test for suspected GPA and MPA, but actual practice varies among physicians. Here, we retrospectively analyzed ANCA test results, focusing on new cases of ANCA-associated vasculitis, and compared the utility of IIF and IA to guide appropriate test selection.

Methods
From January 2022 to July 2023, 24 new cases of ANCA-associated vasculitis were diagnosed. We checked whether ANCA testing was performed and the results, and compared the turnaround time(TAT) and costs. IIF ANCA tests were performed on a computer-based automated instrument(Helios), and IA ANCA tests were performed on automated instruments(Alegria, Phadia 250) with MPO antigen and PR3 antigen tested simultaneously in a bundled prescription.

Results
Among the 24 cases, there were 6 GPA, 7 MPA, 7 EGPA, and 4 ANCA-associated GN, with varying diagnostic sensitivities. GPA and EGPA had different ANCA positivity rates than previously reported, suggesting potential ethnic variations in ANCA expression and positivity rates. The test sequence and results, summarized in Table 1, showed 21 out of 22 cases had identical concordance between methods, with an excellent concordance rate (kappa value=0.83). TAT for IIF was 3,452 minutes, and for IA was 1,491 minutes for the whole period, but IA TAT increased to 2,748 minutes after implementing a days-of-the-week testing system. Test costs, with a relative value score of 118.99 for IIF and 156.05 for IA, indicated IA cost approximately 2.6 times higher, considering the bundled prescription of both antigens for IA ANCA testing.

Conclusions
Evaluating the utility of both methods for ANCA detection, our study highlights high inter-method agreement in ANCA-associated vasculitis. Considering overall cost and turnaround time, IIF ANCA testing remains effective as a screening test, demonstrating standalone effectiveness.
B-076 Detection of KLHL11 Autoantibodies Using a New Cell-based Indirect Immunofluorescence Assay
Authors: Weiss J , Mindorf S , Jäger D , Sabater L , Pitsch J , Baumgartner T , Becker A J , Budhram A , Honnorat J , Saschenbrecker S , Dalmau J , Komorowski L 
Published: October 2024

Abstract

Background
Autoantibodies against kelch-like protein 11 (KLHL11) were first described in 2019 as markers of paraneoplastic encephalitis. Early diagnosis and treatment are imperative to improve prognosis and outcome of affected patients. Rat brain immunohistochemistry was reported to be not useful in routine screening for KLHL11 antibodies. This study evaluates the performance of a new recombinant cell-based assay for the standardized detection of KLHL11-specific IgG and reports the characteristics of the examined patients.

Methods
Serum (n=9), CSF (n=5) and/or plasmapheresis (n=1) samples from 10 patients with clinical presentations compatible with anti-KLHL11 encephalitis as well as sera from 100 healthy blood donors were analyzed using a prototype indirect immunofluorescence assay (IFA; EUROIMMUN) based on recombinant HEK293 cells expressing human KLHL11.

Results
KLHL11 autoantibodies were detected at high titers in all samples (serum &gt;1:1,000; CSF &gt;1:320; plasma &gt;1:100,000) from all (10/10) patients but in none (0/100) of the blood donors, indicating 100% sensitivity and specificity. Anti-KLHL11-positive patients had a median age of 52 years (range 27-71) and 80% were male. The most common reported clinical presentations were cerebellar syndrome (ataxia), brainstem diencephalic encephalitis, rhombencephalitis and limbic encephalitis. Testicular or ovarian tumors were found in 87.5% (7/8) of the cases with available results from malignancy screening.

Conclusions
The new cell-based IFA enables the sensitive and specific detection of KLHL11 autoantibodies, thus supporting the diagnosis of patients with predominantly paraneoplastic brainstem cerebellar syndrome. Future studies will evaluate assay performance in larger patient cohorts to address the reported association of KLHL11 autoimmunity with a wider spectrum of syndromes and tumors.
B-079 Characterization of an isoelectric focusing method for detection of IgG oligoclonal banding in paired cerebrospinal fluid and serum specimens
Authors: Hosseini S , Beatty P , Remaley A T , Duh S , Christenson R H 
Published: October 2024

Abstract

Background
Qualitative assessment of IgG-specific oligoclonal banding (OCB) in paired serum and cerebrospinal fluid (CSF) samples is useful for evaluating inflammatory conditions of the central nervous system such as multiple sclerosis. Here we characterized the performance of an IgG-specific method using isoelectric focusing on agarose gel matrix for the detection of OCB in paired serum and CSF samples.

Methods
Specimens of 20 paired, simultaneously collected CSF and serum patient samples were tested on Sebia (Hydrasys 2 System) provided by the National Institutes of Health (NIH) Diagnostic Laboratories. We tested these paired samples using the Helena IgG IFE-20 kit (SPIFE® Touch) method and the results were read by two independent individuals blinded to each other’s assessments. The results were compared to the NIH results for agreement. Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) were calculated. Analytical sensitivity of the Helena assay was assessed via serial dilutions of a CSF OCB positive sample (total IgG 4.5 mg/dL).

Results
Figure 1 shows serum and CSF pairs for the control (A), two example positive OCB patients (B & D) and a negative OCB patient (C). The Helena assay was concordant with Sebia for 11/12 positive OCB patients (PPA 91.6%) and 8/8 negative subjects (NPA 100%). 20-fold was the highest dilution that remained positive.

Conclusions
OCB detection using paired serum and CSF samples and isoelectric focusing electrophoresis is considered the preferred method. The Helena IgG IFE-20 assay is such a method and showed high PPA and NPA concordance with the Sebia System. Thus, the Helena OCB assay can be considered an accurate and analytically sensitive method for assessing OCB in serum and CSF.
B-086 Evaluation of Long-Term Adaptive Immune Responses Specific to SARS-CoV-2: Effect of Various Vaccination and Omicron Exposure
Authors: Oh E , Kang H , Jung J , Lee J , Ko G , Park H , Choi A 
Published: October 2024

Abstract

Background
The immune response to SARS-CoV-2 becomes increasingly complex as individuals receive different combinations of vaccines and encounter breakthrough infections. Our study aims to describe the immunogenicity observed over a two-year period in healthy individuals who completed two-dose series and then experienced booster and/or Omicron infection.

Methods
In June 2023, we recruited 78 healthcare workers who had previously participated in clinical research initiated in March 2021 at a single medical center. At 1, 5, 11, and 25 months after second dose, we assessed SARS-CoV-2-specific humoral and cellular immune responses using commercially available immunoassays and surrogate virus neutralization tests, along with interferon gamma (IFN-γ)-based enzyme-linked immunosorbent spot (ELIspot) assay using SARS-CoV-2 spike peptide pools.

Results
As the humoral immune response was monitored longitudinally, robust antibody production persisted after the third antigen exposure, in contrast to the rapid decline observed between the second and third dose injections. All immune metrics tended to increase as the number of vaccine doses increased. We also found a trend toward increased humoral immune response in the homologous mRNA-based vaccine group and enhanced cellular immune response in the vector-based primary series with mRNA booster heterologous combination group. Interestingly, no significant difference was found between Omicron exposure through breakthrough infection and bivalent vaccination. Omicron exposure significantly increased the breadth of neutralizing activity, while it did not significantly alter the cross-reactivity in the cellular immune response.

Conclusions
We identified individuals with diminished neutralization, aiding decisions for future vaccination prioritization. In addition, our findings suggest the role of cellular immunity as an important correlate of long-term protection through cross-reactivity to emerging variants.