bluuebunny/crossref_metadata_2025_split huggingface dataset:
A-290 Evaluation of a Commercial Turbidity Monitoring System Followed by Mass Spectrometry to Rapid Identification of Microorganisms from Urine Samples
Authors: Nurmberger J M , Inoue F M , Lobo A T , Ramadan D R , Tufik S 
Published: September 2023

Abstract

Background
Urinary tract infections (UTIs) are one of the most common bacterial infections in worldwide and represent a worried public health problem, especially due to a significant rise in global antibiotic use in recent years. The purpose of the study was to evaluate the performance of Uro-Quick (UQ) system (Alifax) and the Vitek-MS system (bioMérieux) to identify bacteria isolates directly from urine samples.

Methods
We analyzed 352 clinical samples of urine. From automated screening by UQ system was used 500 µL of homogenized urine sample manually pipetted into a UQ vial containing 4 mL of broth. The inoculated vials were manually introduced into the Uro-Quick reading unit and incubated for 3 h. The signals are processed by software which monitors the growth curves and calculates the microbial count as colony forming units (CFU/mL). Sample preparation to the mass spectrometry (Vitek-MS) was performed using an in-house protocol based on a centrifugation-wash (CW) method. In parallel with the Vitek-MS direct identification, all the urine samples were submitted to standard culture (SC) method on ChromID™CPS® plate by semi-quantitative technique using 1 µL disposable loop, incubated at 35–37°C and the colony counting were read after 24 and 48h of incubation. Bacterial isolates from positive cultures were identified by Vitek®2 System, according to the manufacture’s recommendations. Cultures with the presence of three or more microorganisms were considered negative.

Results
Out of 334 clinical samples, 261 (78.1%) were negative for the growth by UQ system and for the presence of microorganisms by SC, 78 (21.9%) samples were positive with growth as ≥104 CFU/mL by UQ system, of which 32 samples were also positive with microorganism isolated by SC. Among the 78 microorganisms detected on the samples with growth curve by UQ system, 74 (94.8%) were identified to the species level by the mass spectrometry and 4 (5.2%) were not identified. The microorganisms were Escherichia coli (n = 40), Enterococcus faecalis (n = 12), Klebsiella pneumoniae (n = 6), Proteus mirabilis (n = 4), Citrobacter koseri (n = 4), Streptococcus agalactiae (n = 3), Morganella morganii (n = 2), Enterobacter cloacae (n = 1), Citrobacter freundii (n = 1) and Gardnerella vaginalis (n = 1). Among the 32 microorganisms detected by SC, 28 showed the same identification at species level when was compared with direct identification by Vitek-MS.

Conclusion
This study showed that both UQ and CW methods by Vitek-MS technology used together were able to provides a rapid result (&lt;4 h) for bacterial identification directly from urine samples, that can be useful in clinical practices, especially in severe infectious cases like pyelonephritis. So, future studies should address with a larger number of samples to improve the sensibility of this test for different groups of microorganisms.
A-334 Investigation on Use of NHANES Data to Develop Continuous Pediatric Reference Intervals - Pilot Study with Hemoglobin
Authors: Lyle A N , Akinbami L J , Chen T , Pokuah F , Kit B K , Vesper H W 
Published: September 2023

Abstract

Background
Accurate Pediatric Reference Intervals (PRIs) are critical for assessing health, diagnosing disease, and establishing treatment efficacy. A recent literature review established that current PRIs are inconsistent, and partitioning reference intervals into arbitrary age groups may conceal the underlying biochemistry of child development. To overcome these challenges, continuous PRIs derived using specimens collected with standardized procedures from a well-defined population were proposed. The National Health and Nutrition Examination Survey (NHANES) meets these criteria and could be used to provide accurate PRIs for public health and clinical community use. However, no U.S. studies have described developing continuous PRIs for biomarkers. This study investigates a potential approach to develop continuous hemoglobin PRIs with NHANES data.

Methods
Total hemoglobin values for children and adolescents 1–19 years from NHANES 2011–2018 were assessed. To exclude potentially abnormal hemoglobin values, individuals with diabetes, anemia, BMI &gt;95th percentile, serum cotinine &gt;10 ng/L, C-reactive protein &gt;10 mg/dL, and self-reported tobacco use, or poor health were excluded. Hemoglobin values at the 5th, 50th, and 95th percentiles were estimated at 6-month increments of age for males and females using survey weights. Continuous curves over the age range were then generated using smoothing methods.

Results
The initial sample size was 16 315, of which 3 183 had missing hemoglobin values. After applying exclusions (n = 3 311), the final sample size was 9 821, of which 51.8% were males and 48.2% were females. Males had higher hemoglobin levels with a steeper slope in the curve over the age range and an increase in slope with adolescence, whereas hemoglobin levels in females peaked around age 12 before plateauing.

Conclusion
This investigation suggests that cross-sectional NHANES data can be used to develop continuous hemoglobin PRIs that reflect the physiologic changes commonly obscured by age group binning. More detailed assessments of appropriate sample exclusions and smoothing methods are underway.
A-370 High Rates of Potassium, Chloride and Hemoglobin Discordances in Split Samples Drawn within 1 minute and Analyzed on Point of Care GEM 5000 and Central Laboratory Roche Cobas 8000 and Sysmex Analyzers
Authors: Cembrowski G , Xu Q , Sadrzadeh H 
Published: September 2023

Abstract

Background
Previously, we used serial intensive care unit patient data as well as split sample glucose comparisons to characterize the analytical performance of the GEM 4000 and its tendency to generate outliers in the early to late evening. In this work, we summarize the discordance rate of 2 years of split specimens (minimally 17 700 patient care samples) that were drawn within 1 minute of each other and analyzed on the GEM 5000, Roche Cobas 8000 and Sysmex analyzers.

Methods
Two years (2020 and 2021) of GEM-central laboratory Cobas 8000 and Sysmex comparisons were obtained for potassium, sodium, chloride, glucose and hemoglobin (Sysmex). We used the GEM's iQM2 control (drift) limits to define discordant differences between the GEM and Roche/Sysmex analyses. We graphed the differences vs time of day and applied Dahlberg's formula to derive the magnitude of the running variation of the differences.

Results
The Table summarizes the drift limits, the number of comparisons performed over the two-year period and the average incidence of discordances over the 24 hour period. What strikes the casual observer is the asymmetric distribution of the discordances. More subtle is the lower frequency of potassium and hemoglobin discordances in the early morning and the higher frequency in the late afternoon and evening. The Dahlberg running variation graphs readily demonstrate this diurnal pattern.

Conclusion
The GEM 5000 overcalls increases in potassium, decreases in chloride and increases in hemoglobin. We recommend that other laboratories verify these findings.
A-388 Evaluation of Performance of the nBili Assay on the RAPIDPoint®500e Analyzer Compared to the Total Bilirubin Assay for the Dimension EXL200 and Atellica CH Analyzers in Neonates Blood Samples
Authors: Paula R F , Lamo T C , Lage M S , Midrigal A D 
Published: September 2023

Abstract

Background
Neonatal hyperbilirubinemia is very common, with 60% of term newborns (NB) and 80% of premature neonates developing this condition. If not diagnosed and treated, can lead to severe complications, with bilirubin encephalopathy (BAE) being one of the most feared outcomes. Analysis of whole blood samples measured by the RapidPoint®500 Blood Gas Analyzer (RP500) is a technology option that provides rapid bilirubin results with a small sample volume and can also measure other important analytes. However, it is still unclear whether the blood gas analyzer can be used for biochemical dosage of bilirubin in newborns.

Objective
This study aimed to evaluate the clinical and analytical reliability of the method for detecting bilirubin in infants in comparison with classic biochemical analyzers such as Atellica® CH 930 and Dimension® EXL200.

Methods
A comparative clinical study was performed to evaluate the acceptable analytical agreement of total bilirubin results from 41 samples from neonatal patients between Atellica® CH 930, Dimension® EXL200 and RapidPoint®500 analyzers. Data were analyzed using Vericheck® software.

Results
Forty-one whole blood samples from newborn patients were analyzed for total bilirubin measurement. The range of analyzed results was from 2.7 to 20.8 mg/dL. Were considered for the analysis of clinical data: gestational age, weight, age, visual assessment of the newborn, criteria for hospitalization, whether phototherapy was performed and how long it took. In the regression analysis, it was possible to obtain a Pearson regression coefficient of 0.9806 between the Atellica® CH 930 and RP500 analyzer. The average of the values obtained with the RP500 was 10.8 and for the Atellica® CH930 it was 11.10, obtaining a percentage difference of means of 2.70%. In comparison with the Dimension®EXL200 analyzer, it was possible to obtain a Pearson correlation coefficient of 0.9814. The average of the values obtained with the RP500 was 10.8 and for the Dimension it was 9.32, resulting in a percentage difference of mean of 15.83%.

Conclusion
The study showed good results for analytical comparability between analyzers. There was no change in the clinical management according to the criteria analyzed in conjunction with the laboratory analyses, making it possible to guarantee the safety of using the RP500 platform in the diagnosis and follow-up of newborns with suspected hyperbilirubinemia.
B-007 Measurement of Cytokines in Bronchoalveolar Lavage (BAL) Fluid and CSF Supports Model Development for Discovery Programs
Authors: Lambert T , Lynch K , Cortina R , Schultz M , Lewandowski T , Sellers T 
Published: September 2023

Abstract
In our laboratory, increased demand for cytokine measurements to support both safety and efficacy endpoints across discovery programs has also resulted in cytokine analyses in biological fluids other than routine serum or plasma samples. Recently we have evaluated cytokines in bronchoalveolar lavage (BAL) fluid and CSF to support a mouse respiratory infection and a rat neuroinflammatory model, respectively. Fit-for-purpose validation of these sample types is necessary to confirm cytokine methods are suitable for use, including selection of optimal sample dilutions to reduce or eliminate any matrix effects or interferences. Meso Scale Discovery® (MSD Gaithersburg, MD) methodology was used for measuring cytokines and validation parameters included precision and accuracy of calibration curves (CV% and %Relative Error &lt;20%) to confirm LLOQ and ULOQ for each cytokine method, precision of results for quality control and study samples (CV ≤ 20%) and linearity of response in samples. In development of the mouse respiratory infection model, cytokines IL-1β, IL-6, KC/GRO and MCP-1 were increased in BAL fluid (up to 2892-fold) 20 h post-infection compared to sham and vehicle control groups. Once the model was established, treatment of mice with Compound A demonstrated statistical decreases in these cytokines in BAL fluid compared to an infected control group. Dilutional linearity demonstrated that a minimal required dilution of 1:2 was required for mouse BAL fluids. In support of development of the rat neuroinflammatory model, cytokines IL-1β, IL-6, KC/GRO, MCP-1 and TNF-α were increased (325X, 13X, 28X, 23X and 7.7X, respectively) in CSF compared to plasma at 24 h post treatment. Dilutional linearity evaluations demonstrated that CSF samples can be run neat but a 1:4 dilution was required for plasma samples. In conclusion, fit-for-purpose validation confirmed MSD methods were acceptable for use in supporting these drug discovery models.
B-010 Comparison of Manual Urine Dipstick and Microscopy With Automated UC-3500 and UF-4000 Sysmex UN Series Urinalysis; A Comparative Experimental Research Approach at an Urban Referral Hospital in Ghana
Authors: Toboh E , Ephraim R K , Osei Darkwah K , Afriyie Gyamfi N , Duah Agyemang L , Kumah Forkuo E , Antwi P , Appiagyei K 
Published: September 2023

Abstract

Background
Urine analysis is one of the most common tests for assessing urinary-tract and kidney diseases. In recent years several automated instruments examining urine have been introduced. Though the introduction of automated urine analyzers is expected to reduce the labour involved, turnaround time and potential assay variations, manual urine analysis remains the gold standard or reference method for the analysis of urine. The new Sysmex UN-Series is believed to offer superior performance than other automated systems and manual methods.

Methodology
A total of 67 routine freshly voided midstream urine samples were analyzed within 1 hour in our study. The results of the automated system were compared with the results of the manual processing which consisted of physical, dipstick chemistry and sediment analysis. Correlation and concordance/agreement between the automated and the manual system were assessed by Bland-Altman plot and Cohen’s Kappa analysis respectively.

Results
There was a significant fair agreement between the manual analysis and Sysmex UF-3500, in the determination of urine physicochemical parameters (k = 0.193, P = 0.004). Both showed a significant moderate correlation (r = 0.593, P &lt; 0.001) and a significant fair agreement (κ = 0.109, P &lt; 0.001) for specific gravity and pH determination respectively. The best concordance between the two methods was in the nitrates (κ = 1.000, P &lt; 0.001). Both systems recorded strong positive correlation for RBC (r = 0.951 and R2 = 0.904) and WBC (r = 0.91 and R2 = 0.822, P &lt; 0.001) counts. Together, they had a significant good agreement [(65/67(97.0%), κ = 0.734, P &lt; 0.001)] and a significant fair agreement [(48/67 (71.6%) κ = 0.065, P = 0.491)] for cast and bacteria counts correspondingly.

Conclusion
We conclude that the new automated Sysmex-UN series urine analyzer can be safely used in our laboratory since it demonstrated good performance and compatibility with the manual method. We recommend that microscopy results of the automated platform should be confirmed by manual microscopy, particularly in pathological samples.
B-023 Optimizing Measurement of Homocysteine in an Emergency Care Pathway
Authors: Grzych G , Marchand D , Clarence D , Emeline G , Schult R , Van Nieuwenhuyse E , zerimech F 
Published: September 2023

Abstract

Background/Context
New indications for homocysteine measurement have emerged in recent years, and homocysteine is now being used as a marker of nutritional deficiency as well as a marker of nitrous oxide intoxication and there is a need to return quickly results to adapt the treatment and orientate diagnosis. Current rapid methods are not adapted to extremely high values encountered which are frequently greater than 50 µmol/L that need use of mass spectrometry that is unfortunately not adapt to emergency. Hence, we evaluated here a new immunological method that allows for the reliable and rapid rendering of homocysteine results in order to integrate it into our care pathways.

Method
We prospectively measured plasma homocysteine using both liquid chromatography-mass spectrometry (UPCL—Sciex AP 3200) and the Chemiluminescence Immunoassay (CLIA) method (Maglumi-Snibe). To limit the bias for each assay, the analyses were performed on the same EDTA plasma sample with the same pre-analytical treatment. Bland-Altman plots and Deming regression were used to assess agreement between the homocysteine LC-MS/MS method and homocysteine CLIA method.

Results
Our study included 169 paired samples. The intra- and inter-assay imprecision was comprised between 0.73–2.21% and between 2.75–3.73%, respectively. Linearity, without sample dilution, was acceptable in the range of 5–70 mol/L. This CLIA assay correlated with the HCY LC-MS/MS assay with a slope of 0.9334, intercept of 1.750, R2 = 0.9637 and average bias of −0.6867 μmol/L.

Discussion
The CLIA method produces results comparable to mass spectrometry while significantly reducing analysis time and result delay. This method is thus more appropriate when homocysteine is used not only for emergency diagnosis but also for nutritional monitoring of the patient. This method also allows for the measurement of extremely high concentrations, which are becoming more common in laboratories.
B-044 Analytical validation of an serum glycerol measured by nuclear magnetic resonance spectroscopy NMR
Authors: Wang Q , Scott R , Meeusen J , Donato L 
Published: September 2023

Abstract

Background
Glycerol kinase deficiency (GKD) is a rare X-linked recessive disorder biochemically characterized by hyperglycerolaemia. Adults with GKD are usually asymptomatic. However, they often present with pseudohypertriglyceridemia because most clinical triglyceride methods measure enzymatically generated glycerol from triglycerides. Currently, assays for measuring plasma glycerol are lacking. We describe a preliminary validation of glycerol measured by nuclear magnetic resonance spectroscopy (NMR).

Methods
Serum glycerol was measured by NMR (Numares AG, Regensberg, Germany) using a Ascend 600 NMR (Bruker, Billerica, MA). Stability and matrix effects were determined by repeat measurement of 10 freshly collected samples following various storage conditions. Normal donors were recruited for reference interval (n = 143). Analytical specificity was assessed by spiking red cell lysate, bilirubin and intralipid. Precision was assessed by measuring three pools five times for five days. Accuracy was performed by spiking known concentrations of glycerol. Accuracy was assessed using an enzymatic method (Randox Laboratories, Ltd. County Antrim, UK) on a Roche Cobas c501 (Roche Diagnostics, Indianapolis, IN) as reference.

Results
Measured glycerol increased over time in both serum and plasma, however, prepared samples were stable on the instrument for up to 24 hours. Measured glycerol was not impacted by hemoglobin (1000 mg/dL) or bilirubin (625 mg/dL), however, spiking Intralipid® prevented any measurement. NMR and enzymatic assays strongly correlated, with a constant bias (Table 1). Repeatability and reproducibility were &lt;10% CV and % recovery from glycerol standard were &gt;80% for all concentrations.

Conclusion
Pre-analytical stability, imprecision and accuracy were acceptable for clinical measurement of glycerol using NMR. While there is a significant systematic bias with enzymatic methods, further studies in normal and disease populations will be necessary to determine clinical impact.
B-048 Performance Evaluation of the New Anti-Streptolysin-O Assay on Mindray BS-2800M System
Authors: Chen W , Liu S , Jiang M , Wang J , Dai J 
Published: September 2023

Abstract

Background
Elevated serum concentrations of Anti- Streptolysin-O(ASO) can be used to provide serologic evidence of past or present infection by β-Hemolytic Streptococci. Increasing serum concentrations of ASO antibodies are produced in response to ASO exotoxins secreted by the bacteria. Measurement of ASO antibody levels in serum can be used as an aid in the diagnosis of diseases such as glomerulonephritis, rheumatic fever, bacterial endocarditis, tonsillitis, and scarlet fever, etc. The New ASO assay has been evaluated on Mindray BS-2800M that is an automated, high throughput, and low cross-contamination system. The evaluation of this assay included precision, linearity, dilution accuracy, interference, high dose hook, and method comparison studies.

Methods
The new ASO reagent contains R1 buffer and R2 with latex particles conjugated with in-house made ASO antigen. The R1 is incubated with human serum sample containing ASO antibodies for 5 min at 37°C and then R2 is added. After another 5 min of incubation, immune-aggregation complex is formed. The increased turbidity is measured at 570 nm. By constructing a six-level calibration curve (water is used as reagent blank) from the absorbances of calibrators, the ASO antibody concentration of the sample is determined.

Results
The precision study was run according to EP05A3 with two commercial controls (approximately 80 and 300 IU/mL) and two serum sample pools (approximately 150 and 400 IU/mL) on the Mindray BS-2800M system. The repeatability and within-lab CVs ranged from 0.8% to 2.0% and 2.0% to 6.0%, respectively. The analytical linearity of the assay was determined as from 20 IU/mL to 1000 IU/mL with the limit of blank of 2 IU/mL and limit of detection of 10 IU/mL. The dilution accuracy was evaluated by diluting high ASO level samples at upper region of assay range using saline with 5-fold and run neat and diluted samples. The deviation in recoveries between diluted sample after calculation and the neat sample was found to be less than ±10%. The new ASO assay showed &lt;±10% interference with bilirubin (conjugated or free) up to 40 mg/dL,hemolysate hemoglobin up to 1000 mg/dL,Intralipid up to 1000 mg/dL,and Triglycerides up to1000 mg/dL. The assay on the Mindray BS-2800M system(y) correlated well with the ASO assay(x) on the Beckman AU5800 system:y = 1.01 x + 1.55(r = 0.9514,n = 95,range:50–971 IU/mL). No prozone was observed with the assay on the Mindray BS-2800M system up to the highest ASO antibody concentration of 5000 IU/mL.

Conclusion
We conclude that the New ASO assay with in-house developed ASO antigen raw material, when used on the Mindray BS-2800M system, can measure serum ASO antibody concentrations precisely and accurately over a broad range. It is suitable for use in routine clinical laboratories.