bluuebunny/crossref_metadata_2025_split huggingface dataset:
A-287 Evaluation of Urinalysis Reflex to Culture in Long-Term Care Facilities: Is It Worth it?
Authors: Khoury R , Gandhi A , Patel P , Gudaitis D , Gudaitis P 
Published: September 2023

Abstract

Background
Urinary Tract Infection (UTI) is one of the second common infections among the geriatric population. It is more common in women than men and the incidence increases with age. UTI can cause serious complications and it is a significant cause of morbidity and death. The high mortality rate is largely due to delayed presentation and the development of bacteremia/sepsis. Physicians rely heavily on urinalysis to diagnose UTI, and it is one of the most frequently requested tests; however, the need to reflect to urine culture became more in demand to cut the cost of test not needed without the sacrificing of patient care.

Methodology
4307 urine samples were collected for urinalysis and culture from residents in Long-Term Care Facilities (LTCF) over a period of 5 weeks. Urinalysis and microscopy were done using IQ WORKCELL automated system. All the specimens were cultured; the culture was done using MicroScan Walkaway96 conventional panels. We used urine culture as the reference standard, no growth or &lt;10 000 colony-forming unit/mL were considered negative, cultures with &gt;50 000 colonies colony-forming unit/mL were considered positive. UA is considered positive if it was positive leukocyte esterase, WBC &gt; 5, nitrate, or had &gt;moderate bacteria. We compared positive UA to the culture outcome. Statistical analyses were done using Analyse-it.

Results
Women represented 64.7% of the samples tested; the positivity rate was 49.2% (52.3% for women and 43.4% for men) and 7.0% of the all the cultures had mixed flora. Urinalysis identified 3038 as positive UA, only 1941 (63.9%) had positive culture and 846 (43.6%) had negative culture. Urinalysis identified 1269 samples as negative, 176 samples (13.9%) of them had positive culture.

Conclusion
The use of negative urinalyses to reflex to culture would help eliminating the majority of the cultures that are not necessary. However, avoiding the culture will risk missing infection in 13.9% of the negative urinalysis samples. In addition, more than one third of the positive urinalysis will require unnecessary cultures. Although the use of reflex will help eliminating the unnecessary culture, we have to remember that urinalysis and microscopy still lack the sensitivity and specificity to be used alone to diagnose urinary tract infection; urinalysis should not be the only marker for UTI, it should be used in conjunction with patients clinical diagnosis. The high positivity rate for UTI in LTCF adds to the complication of the reflex testing. More work needed to establish better parameters and algorithm to be used when screening patients for UTI using urinalysis.
A-289 Emergence of Unusual Non-Fermentative Gram-Negative Bacilli Associated to COVID-19 Period at Brazilian Hospitals
Authors: Nurmberger J M , Inoue F M , Lobo A T , Ramadan D R , Tufik S 
Published: September 2023

Abstract

Background
Since the global pandemic of coronavirus disease (COVID-19), some studies have reported on the emergence of opportunistic nosocomial pathogens associated with co-infection on the outcome of COVID-19 patients. The aim of this study was to describe the increase of six unusual species of Non-fermentative Gram-negative bacilli (NF-GNB) clinical isolates recovered from inpatients in several Brazilian hospitals comparing pre-Covid-19 (January 2018 to December 2019) period vs Covid-19 (January 2020 to December 2021) period.

Methods
This study design was a retrospective, observational analysis based on microbiological data of emergent NF-GNB isolates, detected in several Brazilian tertiary hospitals. The bacterial identification was performed by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF/MS) and the susceptibility of antibiotics was determined using disk diffusion method.

Results
During the 48 months period, a total of 1665 (2018; 349), (2019; 351), (2020; 485), (2021; 480) emergent NF-GNB isolated from blood (n = 744), respiratory tract (n = 239), skin and soft tissue (n = 264); urine (n = 119), catheter (n = 101), fluid and secretions (n = 113), Cerebrospinal fluid (n = 12) and others (n = 73) were analyzed. The frequency of NF-BGN according to species level identification was Stenotrophomonas maltophilia (1040; 62.5%), Burkholderia cepacea complex (457; 27.4%), Elizabethkingia meningoseptica (64; 3.8%), Elizabethkingia miricola (31; 1.8%), Ochrobactrum anthropi (69; 4.1%) and Ochrobactrum intermedium (4; 0.2%). The prevalence of these NF-BGN detected in pre-Covid-19 period (2018–2019) and Covid-19 period (2020–2021) were 42% and 58%, respectively. The incidence of Stenotrophomonas maltophilia, Burkholderia cepacea complex, Elizabethkingia spp. and Ochrobactrum spp. infection was (47.7% and 52.3%), (42.9% and 57.1%), (43.2% and 56.8%) and (50.7% and 49.3%) among female and man patients, respectively. For Stenotrophomonas maltophilia, Burkholderia cepacea complex and Ochrobactrum spp. the main age range was over 60 years (44.5%, 44.9% and 42.5%) while for Elizabethkingia spp. the main age range was 0–10 years of age with 42.5% of cases in the pre-COVID-19 period and over 60 years old with 43.9% in the COVID-19 period. Compared the two periods (2018–2019 vs 2020–2021) for Stenotrophomonas maltophilia the resistance rate to levofloxacin and sulfamethoxazole-trimethoprim was (3.9% vs 4.6%) and (4% vs 4.2%), respectively.

Conclusion
Our data point to a scenario wherein the presence of opportunistic pathogens may have been intensified by the covid-19 pandemic. Further studies should be carried out to clarify these findings.
A-330 Trending Treatment of Transplant-associated Thrombotic Microangiopathy (TA-TMA): Validation and Performance of Soluble C5b-9 on the Dynex DS2 Platform
Authors: Wilson R J , Johnson L M , Bhandari M , Dickerson J A 
Published: September 2023

Abstract

Background
The complement system membrane attack complex is comprised of the C5b fragment along with C6, C7, C8 and C9 polymers that form a pore to disrupt a membrane during complement activation. Inactive complexes that are not membrane-bound combine with Protein S to form soluble C5b-9 (sC5b-9). Elevated concentrations of sC5b-9 are associated with risk of development of hematopoietic stem cell transplant-associated thrombotic microangiopathy (TA-TMA), which can be treated by eculizumab therapy. TA-TMA is a complex syndrome of abnormal cell activation, microvascular hemolytic anemia, and complement dysregulation which can lead to multiple organ dysfunction and death. Therefore, recognition of this syndrome is critical in the context of not only preventing poor outcomes in patients but also promoting stewardship of an expensive, yet effective therapy. Our laboratory evaluated the performance of the Quidel Microvue sC5b-9 Plus enzyme immunoassay on the Dynex-DS2 platform for clinical use.

Methods
EDTA plasma samples were collected from remnant CBC samples ordered for bone marrow transplant (BMT) patients and other patients not at risk for TA-TMA. Validation studies included method correlation, inter- and intraday precision, assay linearity, hemolysis interference, and other experiments. Clinical accuracy was assessed by performing a retrospective review of sC5b-9 results from BMT pediatric patients at risk for TA-TMA.

Results
Intraday precision was 6.7%, 7.1% for the manufacturer low- and high-quality control materials, respectively and 9.9% for an in-house prepared plasma pool. Inter-day precision was 9.8% and 5.3% for manufacturer low- and high-quality control material, and 12.8% for an in-house plasma pool over a period of at least five days. The linearity of the assay was verified with a lower limit of quantification of 80 ng/mL and upper limit of qualification of 1600 ng/mL. Our method comparison indicated good correlation with send-out results, with an average percent bias of -10% and Pearson's r2 value of 0.986. The assay showed no interference up to 100 mg/dL of hemolysis. Retrospective analysis of a few patient results demonstrated that weekly monitoring of sC5b-9 concentrations detected rapid increases in patients at risk of TA-TMA, which prompted treatment with eculizumab therapy. Given the analytical performance, at least 2- to 3-fold changes in sC5b-9 concentrations are clinically meaningful when tracking trends in patients at risk for TA-TMA.

Conclusion
Our results indicate the Quidel Microvue sC5b-9 Plus enzyme immunoassay on the Dynex-DS2 platform had acceptable analytical and clinical performance for monitoring trends in patients at risk for TA-TMA.
A-357 Performance of Blood Urea Nitrogen on the epoc Analyzer
Authors: Dilks M , Evans L M , Goldsmith B M 
Published: September 2023

Abstract

Background
The epoc Blood Analysis System (Siemens, Tarrytown, NY) performs blood gases, electrolytes, and metabolites using a Blood Gas Electrolyte and Metabolite (BGEM) Test Card panel on 92 uL of whole blood. The BGEM Test Card uses potentiometric sensors to measure sodium, potassium, chloride, ionized calcium, pH, pCO2; amperometric sensors to measure pO2, glucose, creatinine, and lactate; and a conductometric sensor to measure hematocrit. Results are available in 3–10 minutes, depending upon the time of sample injection. TJUH implemented the epoc in its ICUs in 2012 to provide rapid, whole blood Point of Care (POC) results, then expanded to other locations (Emergency Department, Outpatient Radiology, Cardiothoracic Surgery). Siemens recently added a potentiometric sensor for measurement of Blood Urea Nitrogen (BUN) to its BGEM card. We evaluated this card for possible future use.

Methods
Precision and method comparison studies were performed at our Center City location. Inter- and intra-precision studies were performed on two levels of controls (Eurotrol, Elizabethtown, KY). Remnant whole blood was collected from 30 patients. Comparison studies were performed on the Piccolo Xpress (Abbott, Princeton, NJ), which provides a whole blood BUN measurement using a coupled-enzyme reaction.

Results
Intra-assay precision for epoc BUN (n = 20, 2 devices) was 2.8%CV and 6.5%CV for Levels 1 and 3, respectively. Inter-assay precision for epoc BUN (n = 20, 2 devices over 10 days) was 2.4%CV and 7.1%CV for Levels 1 and 3, respectively. Method comparison for BUN (n = 30) was: mean = 42, median = 29, r2 = 0.9889, y = 0.8840x-3.6416.

Conclusion
The epoc BUN studies showed comparable results when compared to the Piccolo Xpress. Previous studies showed good correlation between whole blood on the Piccolo Xpress and plasma on the Roche Cobas c702 which is also a coupled-enzyme reaction; therefore the test is considered acceptable for implementation at our Center City sites where epoc is currently in use.
A-367 Development of a Novel Handheld Platform for Real-time Fluorescence-based Nucleic Acid Detection
Authors: Hong Y , Song Q , Gao Y , Liua Y , Wen W 
Published: September 2023

Abstract

Background
Real-time fluorescent nucleic acid detection systems are usually large and complex to operate. In the past three years, the pandemic outbreak of COVID-19 has sparked a variety of point-of-care testing (POCT) nucleic acid detection platforms. However, most of these platforms need to be paired with specific reagents, and many detection reagents on the market cannot be applied to these POCT platforms.

Methods
In this research, a novel handheld real-time nucleic acid detection device was invented. The device uses a heating element to adjust the temperature in time with a sensor to ensure accuracy. The optical detection module is highly scalable and can be extended up to 6 fluorescence channels. The FAM and HEX fluorescence channels were utilized in this experiment. This platform is open and can adjust temperature for various types of isothermal nucleic acid detection, such as LAMP, RPA, and RCA.

Results
We used a commercial COVID-19 reagent kit with our device to get results in just 30 minutes, detecting SARS-CoV-2 virus as little as 500 copies/mL. Our system provides a reliable and efficient tool for COVID-19 testing in a variety of settings.

Conclusion
The handheld device was also used to test for flu A and mycobacterium tuberculosis, with good results. This device can be used not only for pathogen detection of human diseases, but also in pathogen detection for animals and plants, food safety, environmental monitoring, and other fields, thus expanding the application range of nucleic acid detection and making it simpler and more convenient to use.
A-382 Evaluation of the Labcorp TrueSpinTM for Decentralized Blood Sample Centrifugation
Authors: Iacovetti G , Collier B , Setzer S , Peevler M , Ragar J , Brandon W , Chappell M , Grant R P , Sommer G J , Schaff U Y 
Published: September 2023

Abstract

Background
The increased demand for decentralized blood sample collection presents numerous operational challenges for diagnostics providers. Sample degradation including sample hemolysis due to time, temperature, and handling between collection and laboratory analysis leads to limited test menus and unreliable results. Here we evaluate the light-weight, portable Labcorp TrueSpin™ for rapid point-of-care blood separation using commercially available microvolume blood collection tubes. The TrueSpin is a class I FDA registered device designed for layperson use. The centrifuge runs on AA batteries and separates a blood sample in five minutes.

Methods
Here we show results of studies evaluating sample quality and analyte stability in serum samples collected into gel microtubes and processed using the TrueSpin. Hemolysis and residual red blood cell (RBC) concentration are compared between samples separated using the TrueSpin and conventional centrifugation. Additionally, we evaluate serum-based chemistry analyte stability in both separated and unseparated samples stored for three days refrigerated and unrefrigerated.

Results
No significant difference was seen in hemolysis or residual RBC concentration in serum samples prepared by TrueSpin compared to the reference centrifuge method. Furthermore, we show that many common serum-based chemistry analytes have limited (&lt;1 day) stability if uncentrifuged, but improve to ≥3-day stability following TrueSpin separation and refrigerated or room temperature storage (see Table 1).

Conclusions
These findings suggest that the TrueSpin is a simple and effective solution for remote sample separation and may enable broader test menus and increased test result reliability for decentralized sample collection pursuits.
B-005 Blood pH and Phosphate Tend to Follow an Inversely Correlated Homeostatic Status
Authors: Islam S , Osa-Andrew B , Cao J , Muthukumar A R , Jones P M , Hashim I 
Published: September 2023

Abstract

Background
Phosphorus containing biomolecules perform an essential biochemical function in maintaining extra and intracellular acid-base status. Maintaining normal concentration (2.5–4.5 mg/dl) of phosphorus is indispensable for optimal cellular function and homeostasis. Serum concentration of phosphorus (mainly inorganic orthophosphates) is an indicator of H2PO4−/HPO42− acid-base buffer condition. Disturbance of pH could be an immediate impact of many respiratory and metabolic morbidities. Extra/intracellular redistribution of phosphates in response to an abnormal pH is an established homeostatic phenomenon. Failure to maintain an appropriate phosphate level to support the extra/intracellular redistribution may result in a pH shock. Therefore, it is important to have a clear understanding on how blood phosphate and pH levels are interconnected which could assist in guiding therapeutic interventions to fix phosphate abnormalities and acid-base disturbances. This study examined the homeostatic correlation between blood pH and phosphate level among hospitalized and ambulatory patients.

Methods
Serum phosphorus concentration and pH were retrieved from the biochemical profiles and arterial blood gas data of hospitalized and ambulatory patients who presented or admitted our tertiary care level university hospital during the first week of July, 2021. Logarithmic (base ten) values of phosphorus concentration were determined to normalize the distribution of the phosphorus data more uniform. Correlation analyses between phosphorus/log[phosphorus] and pH were performed by GraphPad PRISM version 8.

Results
A total of 101 corresponding blood gases and phosphate levels were obtained. Both phosphorus and log [phosphorus] values of the patients displayed an inverse correlation with arterial pH (Figure 1a and b). Pearson r values demonstrated a negative correlation between phosphorus/log [phosphorus] and pH (−0.6737 and −0.6450, respectively).Fig. 1.

Conclusion
Monitoring of phosphate levels provide an early indication of acid base status. Phosphorus level maintains an inverse correlation with pH profile. Therefore, a therapeutic manipulation of phosphorus or pH may have a mutual effect requiring further investigation.
B-021 Analytical Performance of Thyroid Function Test on DxI800 System
Authors: Jang J , Kang H , Jang H , Rim J , Lim J 
Published: September 2023

Abstract

Background
Thyroid function tests (TFT) which usually include thyroid stimulating hormone (TSH), total triiodothyronine (TT3), and free thyroxine (FT4) are widely applied in clinical practice for screening, diagnosis and monitoring of thyroid disease. We evaluated analytical performance of TSH, TT3, and FT4 using DxI800 (Beckman Coulter, USA) including comparison to Alinity I (Abbott, USA).

Methods
Precision was determined by percent coefficient of variation (%CV) measuring low, medium, and high levels of quality control material for 5 days with one run per day, 5 replicates per run. Linearity was evaluated using 5 levels of patient serum samples and concentrations were determined by the mean value of two replicates of each level. Method comparison was performed by Passing-Bablok regression using 40 patient serum samples.

Results
The within-run imprecision at low, medium and high level were 1.50%, 1.77%, and 2.59% for TSH; 4.10%, 2.45%, and 2.84% for TT3; and 3.23%, 2.76%, and 2.19% for FT4. The within-laboratory imprecision at low, medium, and high level were 1.61%, 1.91%, and 2.87% for TSH; 4.33%, 3.73%, and 3.70% for TT3; and 3.36%, 2.76%, and 2.20% for FT4. Linearity of TFT on DxI800 was demonstrated in the range of 0.01–44.68 µIU/mL, 0.09–7.40 ng/mL, and 0.18–5.52 ng/dL for TSH, TT3, and FT4, respectively. Method comparison between DxI800 and Alinity I showed a slope of 1.21 and intercept of 0.05 (correlation coefficient R = 0.994); a slope of 0.95 and intercept of 0.13 (correlation coefficient R = 0.971); and a slope of 1.81 and intercept of −0.88 (correlation coefficient R = 0.969) for TSH, TT3, and FT4, respectively.

Conclusion
DxI800 showed acceptable performance in terms of precision and linearity for TFT assay including TSH, TT3, and FT4. This study demonstrated that TFT on DxI800 are suitable in clinical laboratory.
B-033 Impact of Red Blood Cell Sediment on HbA1c Measurement
Authors: Nanthakhan T , Jaru-arayanun M 
Published: September 2023

Abstract

Background
HbA1c testing using EDTA whole blood as specimens is essential for monitoring glycemic control in diabetic patients. In the laboratory that using total laboratory automation system, the transportation process might be impact the quality of HbA1c result according to red blood cell sedimentation. This study, we aimed to evaluate the impact of HbA1c result from red blood cell sediment which happen in transportation process of total laboratory automation system.

Methods
HbA1c samples (n = 50) were mixed once and HbA1c levels were determined by using an Alinity c analyzer at an initial time point (T0 = 0 min.), followed by three additional time points (T1 = 7 min., T2 = 15 min., and T3 = 30 min.). The HbA1c levels and samples analyzed at each time point were then used to calculate correlation coefficient, slope, intercept values. The percent difference in these parameter values from all time points was calculated using the analytical criteria of 5% bias according to the National Glycohemoglobin Standardization Program (NGSP) criteria.

Results
We discovered that the correlation coefficient, slope, and intercept values obtained from the samples at T1 are 0.999, 0.994, 0.008, respectively, T2 are 0.999, 0.982, 0.042, respectively and T3 are 0.999, 0.979, 0.028, respectively. The percent difference of all criteria was 0.00% which were not significantly different from those at the initial time point (T0).

Conclusion
This study shows that, the time that using in transportation process in total laboratory automation system at 7, 15 and 30 minutes will not impact quality of HbA1c result even though red blood cell might be sediment before aspirate in the analyzer.
B-050 A Versatile Immunoassay Platform for Fast Multiplex Detection of Protein Biomarkers Based on A Novel Magnetic Particle System
Authors: Cho Y , Moon D , Han K , Choi H , Kim J , Ro Y , Oh B , Song S , Jung Y 
Published: September 2023

Abstract

Background
A major challenge of clinical diagnostic applications in the field of emergency department is the not only fast but also accurate measurement of multiple protein biomarkers with broad dynamic range spectrum. Here, we describe the development of a versatile immunoassay platform, the VEUS (Versatile, Easy, and User-friendly System), with compact size which occupies minimal space.

Methods
The VEUS is designed to enable fast multiplex detection (i.e., 15∼60 minutes) of target proteins at a concentration with a low limit of detection (i.e., &lt;1 pg/mL) by automation of overall immunoassay processes.The system possesses four core technologies enabling entirely automated rapid diagnostics: (1) novel magnetic particles for enabling multiplexed assay using various length of rod-shaped magnetic particles (RSMPs) with conjugated individual antibodies, (2) RSMP movement controlling (up & down/well to well) for increasing antibody-antigen reaction and washing efficiency, (3) a unique optical module for highly sensitive imaging under large field of view for a whole imaging well, and (4) an artificial intelligence (A.I.) based intrinsic program for fast and accurate fluorescent signal analysis which covers detection and classification of RSMP based on their length, and then measurement of fluorescent signal and conversion to biomarker concentration. We evaluated clinical performance of the VEUS platform to diagnose traumatic brain injury (TBI), an emergency disease, as a proof of concept of the versatile immunoassay platform. Among TBI, mild TBI (mTBI) is prevalent in younger population with high level of physical activities that have been linked to increased rate of incidences. Although mTBI is rarely resulted in death, unidentified by the Computed Tomography (CT) and prolonged mTBI as a stealth pathology, may cause life-long disability.

Results
We determined the assay cut-off value from critical concentration of GFAP (Glial fibrillary acidic protein) and UCH-L1 (Ubiquitin carboxy-terminal hydrolase L1) as of 24 pg/mL and 138 pg/mL, respectively. The VEUS performance for a TBI clinical test showed 94.38 % sensitivity and 98.99 % specificity with the clinical serum samples of 89 TBI patients and 97 healthy controls within 50 minutes from the multiplexed assay of GFAP and UCH-L1.

Conclusions
As a versatile immunoassay platform, the VEUS system showed high specificity and sensitivity from the clinical test for the TBI diagnosis. Thus, the VEUS system can contribute to proper treatment for the TBI patients with rapid and accurate clinical results and be also applied for an independent and a precise diagnosis of multiple emergency diseases, such as sepsis, myocardial infraction, heart failure, and stroke which are common in the field of emergency department.