Clinical chemistry最新文献

{"title":"A-118 A simple and effective method to reduce blood culture contamination rate (BCCR)","authors":"Narayan Torke, Dani Bodecker, Allison Boehler, Breanna Caraway, Marella Lucas","doi":"10.1093/clinchem/hvag086.092","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.092","url":null,"abstract":"Background Blood culture (BC) contamination occurs when microorganisms that are not actually causing a bloodstream infection are introduced into a blood culture sample either during phlebotomy, or through skin flora. Blood contamination can lead to inaccurate diagnoses, unnecessary antibiotic treatment, and prolonged hospital stays. Minimizing blood culture contamination rates (BCCR) is an important quality improvement tool. Current benchmark for BCCR in the U.S. is <3%, although many facilities have been able to drive this to below 2% through various strategies. Employing a simple, initial ‘discard tube’ method, our laboratory has shown BCCR can be reduced to significantly lower than 1%. Methods The blood collection site was prepared using established phlebotomy procedures. Upon insertion of the needle into the collection site, the initial portion of the blood drawn was diverted to a ‘discard’ tube (approximately 2.0 mL) and the same needle was subsequently used to aseptically inject blood culture specimens into BD BACTEC culture bottles. These bottles were then placed into BD BACTEC™ FX instrument for incubation and testing. Each bottle contained a sensor which detected increases in CO2 levels produced by the growth of microorganisms. Bottles were automatically reviewed at defined intervals for chemical changes in the sensor which indicated bacterial growth (Positive BC). Positive bottles were removed from BACTEC™ FX, sub-cultured to plates for bacterial/fungal ID and sensitivity, gram stained and tested by PCR for the most common blood culture pathogens. Results A total of 1,511 blood cultures from Emergency Department and hospitalized patients collected over a period of 3 months were included in the study. Of these, 112 cultures were positive for a positivity rate of 7.4%. Three specimens were considered contaminated for a BCCR of 0.2%. This result compared to the pre-study baseline of 2.3% BCCR, indicating an overall performance improvement of 91%. The contamination rate was primarily in the specimens from the Emergency Department, given the serious challenges posed for infection control and prevention. A contaminated BC sample gave a positive reading but did not indicate a clinically relevant result. BC contaminations were determined based on such factors as type of organism recovered, occurrence of the same organism in multiple cultures and patient history, etc. Comparison of the results with the list of organisms on file and generally considered non-pathogenic was a part of the evaluation process. Conclusion Maintaining a low BCCR substantially improves accurate diagnosis of infections. False positive results due to contamination and insufficient blood culture volume can result in such serious consequences as misdiagnosis, repeat diagnostic testing, delayed accurate diagnosis, unnecessary antibiotic exposure, prolonged length of hospitalization and related unnecessary added costs. By implementing a simple, inexpensive blood diversi","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"22 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-173 Impact of Cut-off Adjustment on Inter-Assay Agreement of Anti-Cardiolipin and Anti-ß2 Glycoprotein I IgG Across Three Automated Immunoassay Platforms","authors":"Howon Lee","doi":"10.1093/clinchem/hvag086.475","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.475","url":null,"abstract":"Background Anti-cardiolipin (aCL) and anti-ß2 glycoprotein I (aß2GPI) IgG assays are essential in the evaluation of systemic lupus erythematosus (SLE) and antiphospholipid antibody testing. With increasing adoption of automated immunoassays, concerns have emerged regarding inter-assay variability and overclassification of low-titer positivity, particularly when uniform cut-off values are applied across different platforms. This study compared the diagnostic performance of three automated immunoassays and assessed the effect of cut-off modification on assay concordance. Methods Serum samples from 248 patients (81 SLE and 167 non-SLE) were analyzed for aCL IgG and aß2GPI IgG using three automated platforms: a chemiluminescent immunoassay (BIO-FLASH®), a multiplex bead-based immunoassay (BioPlex® 2200), and a fluorescence enzyme immunoassay (Phadia® 250). Sensitivity and specificity for SLE were evaluated using a uniform cut-off of 20 units. For BIO-FLASH® aCL IgG, additional analyses were performed with elevated cut-offs of 30 and 40 units to assess changes in diagnostic performance and inter-assay concordance. Results At a cut-off of 20 units, marked inter-assay differences were observed for aCL IgG. Sensitivity for SLE was highest on BIO-FLASH® at 62% (50/81), compared with 31% (25/81) on BioPlex® 2200 and 36% (29/81) on Phadia® 250. However, specificity for aCL IgG was lowest on BIO-FLASH® (69%, 115/167), whereas BioPlex® 2200 and Phadia® 250 demonstrated higher specificities of 95% (159/167) and 88% (147/167), respectively. For aß2GPI IgG at the same cut-off, sensitivity ranged from 31% to 49% (BIO-FLASH® 49%, 40/81; BioPlex® 2200 41%, 33/81; Phadia® 250 31%, 25/81), with relatively consistent specificity across platforms (87–91%). Raising the BIO-FLASH® aCL IgG cut-off resulted in a stepwise trade-off between sensitivity and specificity. Sensitivity decreased from 62% at 20 units to 43% (35/81) at 30 units and 33% (27/81) at 40 units, while specificity increased from 69% to 80% (134/167) and 87% (145/167), respectively. Elevation of the cut-off substantially reduced low-titer positivity among non-SLE patients and improved concordance with the other platforms. Conclusion Low-titer aCL IgG results are a major source of inter-assay discordance among automated immunoassays. Application of uniform cut-offs across platforms may lead to reduced specificity and potential overclassification, particularly with CLIA-based assays. Platform-specific cut-off adjustment for aCL IgG improves specificity and inter-assay concordance while preserving acceptable sensitivity, underscoring the need for assay-specific harmonization strategies in routine clinical laboratories.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"465 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-304 Open-Channel Validation of Urea and Phosphorus: Analytical Performance and Reagent Equivalence under Routine Laboratory Conditions","authors":"Sergio Tufik, Kelly Donato, José Dichirico, Renata Pereira, Thais Camargo, Jussimara Nurmberger, Carolina Piccinini, Mariana Viana","doi":"10.1093/clinchem/hvag086.586","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.586","url":null,"abstract":"Background Validation is a complex process performed to confirm analytical performance under routine laboratory conditions. Under regulatory requirements, commercial reagents are validated by manufacturers within a specific analytical system (instrument, reagent, and sample matrix). However, when modifications to an analytical system are necessary, laboratory validation becomes required, especially during supply disruptions, even when product equivalence is recommended and documented by the manufacturer. This process ensures proper system operation, compliance with internal quality requirements, and reliable patient results. This study aimed to evaluate the analytical performance of urea and phosphorus (serum and urine) using Advia reagents on the Atellica CH analyzer in an open-channel configuration. Methods Three studies were performed to determine analytical performance: precision, method comparison, and linearity. For precision, two levels of routine commercial quality controls were analyzed in quintuplicate over five days. Acceptance criteria included compliance with the manufacturer’s instructions for use and/or a variation below one-quarter of the total allowable error (TEa). For method comparison, at least 40 samples were analyzed using the ADVIA® Chemistry Inorganic Phosphorus (IP) reagent (test) and Atellica CH Inorganic Phosphorus (IP) reagent (reference), on the Atellica CH analyzer (all from Siemens healthineers®), with acceptance criteria including a correlation coefficient r²>0.95, agreement within the TEa, and/or semiquantitative analysis (when applicable). For linearity, two samples (high and low concentrations) were selected and mixed to obtain four dilutions (20%, 40%, 60%, and 80%). All six levels were analyzed in duplicate. Acceptance criteria were r² > 0.99 and a difference below ½ TEa. The TEa used in the analysis was derived from the laboratory’s internal quality control program. All analyses were performed using EP Evaluator software, version 12.4. Results The analytical system evaluated in this study was implemented according to the manufacturer’s recommendations, with stated equivalence between the Advia and Atellica reagents. Minor protocol adjustments were implemented to optimize performance on the Atellica CH analyzer in an open-channel configuration, as defined by Siemens technical support. Imprecision ranged from 1.2% to 4.9%, in accordance with one or more of the established criteria. The method comparison analysis showed r²>0.95 and variation within the TEa. Furthermore, in the comparison study, serum urea demonstrated a positive bias of the test method relative to the reference; therefore, a semiquantitative analysis was performed and the generated data demonstrated the absence of clinically significant impact. In the linearity studies, excellent correlation was observed (r²>0.99), with the only limitation related to the difficulty of obtaining high-concentration samples to fully asse","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"7 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-319 INCIDENCE AND CAUSES OF NEEDLESTICK INJURIES CONNECTED WITH BLOOD COLLECTION IN SAUDI ARABIA: A NATIONAL SURVEY","authors":"Ana-Maria Simundic, Waleed Tamimi, Salwa Almrwani, Anwar Borai, Fatima Aldawood, Amerah Thabat, Noof Alobaid, Essa Al Muharraq, Jaffar Khiariy, Ibraheem Alshahrani, Sara Suliman, Maryam Aloqbi, Nada Alnaemi, Hatan Alsubhi, Hind Abdulhakim, Regina Borovac, Daniel Leitner, S N E Z A N A JOVICIC","doi":"10.1093/clinchem/hvag086.261","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.261","url":null,"abstract":"Background Needlestick injuries (NSIs) are a significant occupational risk for healthcare workers (HCWs), especially nurses, phlebotomists, and laboratory technicians. Globally, approximately 40–43% of HCWs experience at least one NSI, mainly during procedures with hollow-bore needles such as blood collection, injections, and improper disposal. These injuries expose HCWs to bloodborne pathogens, psychological stress, and financial costs, and are often underreported, with up to half not formally documented. In Saudi Arabia, annual NSI rates range from 11% to 24%, with nurses being most affected. However, limited data exist on NSIs across the different stages of venous blood collection in the country. The Preanalytical Working Group of the Saudi Society for Clinical Chemistry conducted an anonymous survey estimating the incidence and causes of NSIs before, during, and after venous blood collection. Methods An anonymous online survey was conducted using Microsoft Forms from January 14 to 28, 2026, targeting HCWs involved in blood collection in 25 hospitals in cross Saudi Arabia. The 26-question survey explored occupation, experience, safety protocols, awareness of risks, NSI occurrence and timing, reporting practices, and use of safety devices. Data was summarized using counts and percentages in Microsoft Excel. Multivariable stepwise logistic regression was used to identify independent predictors, considering factors like work experience, daily venipuncture volume, and training frequency. Chi-square tests compared proportions. Statistical analyses were performed using MedCalc©, version 23.2.8, with p-values <0.05 considered significant. Results Among 164 HCWs (mostly nurses, 84.7%; laboratory technicians, 7.9%; phlebotomists, 3.6%), 72% (118/164) reported never experiencing an NSI, while 28% (46/164) had at least one during their career. Notably, 7.3% (12/164) reported experiencing NSIs in all three blood collection phases – before, and after. NSIs were most frequently reported after venipuncture, particularly during handling and disposal, with 20.1% (33/164) reporting such events. However, no phase showed a statistically higher incidence of NSIs (?²=0.146, df=1, p=0.7020). Stepwise logistic regression identified several independent predictors of NSI. HCWs with less than one year of experience had lower odds of NSI compared to their more experienced counterparts (OR 0.11, 95% CI 0.01–0.92, p=0.0421). In contrast, those who received only one-time training upon employment (OR 3.76, 95% CI 1.56–9.08, p=0.0032) and those performing 11–20 venipunctures per day (OR 6.95, 95% CI 1.27–38.20, p=0.0256) faced higher odds of NSI. The model showed acceptable discrimination with an AUC of 0.70 and adequate calibration (Hosmer–Lemeshow p=0.96). Conclusion NSIs remain a relevant occupational risk among HCWs performing venous blood collection in Saudi Arabia, with nearly one-third reporting at least one lifetime NSI. Although NSIs occurred across all phases","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"401 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-363 Comparison of comprehensive syndromic versus limited respiratory panel results in a point-of-care setting","authors":"Kylie Sage, Brooklyn Nawrocki, Jay Jones, Tom Robbins","doi":"10.1093/clinchem/hvag086.296","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.296","url":null,"abstract":"Background Syndromic multiplex molecular point-of-care (POC) tests boast high sensitivity and short turnaround times, supporting prompt diagnosis and informed treatment decisions at the time of patient visit (Lucar 2024). The family of BIOFIRE® SPOTFIRE® Respiratory/Sore Throat (R/ST) Panels are such tests with options for a comprehensive syndromic panel (R/ST Panel) and a condensed menu panel (R/ST Mini) limited to five viral pathogens: Influenza A and B viruses, human rhinovirus, respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The comprehensive R/ST Panel has four additional viral pathogens, the ability to subtype influenza A/H1-2009 and A/H3, and four atypical bacterial pathogens (see Figure 1). When utilizing these types of POC tests appropriately, positive results can reduce antibiotic use, increase appropriate antiviral prescriptions, and may reduce hospitalization time (Schneider 2020, Egilmezer 2018). These outcomes ultimately improve diagnostic stewardship by eliminating the need for serial or individual testing. This analysis demonstrates how the respiratory menu for R/ST Panel Mini and the comprehensive R/ST Panel can increase diagnostic yield. Methods Deidentified patient test results were captured by BIOFIRE® FIREWORKS™ Trends (Trends), a cloud-based pathogen surveillance network for BIOFIRE® systems. Results were limited to 01/01/2025 to 01/31/2026 for the comprehensive R/ST Panel with the nasopharyngeal sample type. The diagnostic yield for all pathogens on the R/ST Panel was compared to the theoretical diagnostic yield for a subset of pathogens present on the R/ST Panel Mini over the course of 2025. Peak pathogen activity was also summarized and compared over time. Results During respiratory season, detection of R/ST Panel Mini pathogens were highest with an average diagnostic yield of 51.8%, and lowest during the late spring and summer months (diagnostic yield = 43.3%). In contrast, the R/ST Panel with all pathogens results in a diagnostic yield of 65.5% during the respiratory season and 56.8% during spring and summer months. The three most common pathogens identified on the comprehensive R/ST Panel that are not included on the R/ST Panel Mini include parainfluenza virus, seasonal coronaviruses, and adenovirus, with >2,500 detections from each virus. Many of these detections occur in the late spring and early summer, after the peak influenza season. Conclusion When respiratory virus transmission is high and contextual and/or operational constraints exist, the SPOTFIRE® R/ST Panel Mini detects five common respiratory viruses, which supports rapid clinical decision-making for patient treatment and management. In the months outside of respiratory season, the comprehensive syndromic SPOTFIRE® R/ST Panel improves diagnostic yield by 14% on average (range: 5% - 22%). The comprehensive SPOTFIRE® R/ST Panel therefore offers robust syndromic testing in a point-of-care setting, wh","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"22 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A-343 A plasma amino acid LC-MS/MS method for the diagnosis and monitoring of inborn errors of metabolism patients","authors":"Adam Ptolemy, Young Kim, Chris MacDonald, Alexander Kolb, Mark Kellogg, Roy Peake","doi":"10.1093/clinchem/hvag086.279","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.279","url":null,"abstract":"Background Quantitative plasma amino acid analysis is essential for the diagnosis and monitoring of inborn errors of metabolism (IEM). Chromatographic amino acid methods utilizing optical detectors are prone to interferences and limited by long analytical run times. We describe the development and validation of a liquid chromatography–tandem mass spectrometry (LC MS/MS) assay designed to provide rapid, sensitive, and interference resistant plasma amino acid testing for pediatric IEM patients. Methods Method development and clinical validation studies were performed using an Acquity™ iClass UPLC coupled to Xevo TQ-S Micro tandem mass spectrometer (Waters Corporation) operated in positive electrospray ionization mode (ESI+). Sample pretreatment was performed using a Kairos™ Amino Acid Kit (Waters Corporation), which utilizes protein precipitation and AccQTag® chemical derivation prior to analysis. Optimization of the sample preparation protocol permitted the use of 20 µL of plasma for testing. All amino acids (N=45) and internal standards were detected as their derivatized products using their respective MS/MS transitions. Column chemistry, mobile phase composition, flow rate and gradient conditions were optimized to provide the greatest isobaric amino acid resolution and sensitivity, within the shortest analytical runtime. Performance of the LC-MS/MS assay was initially evaluated through assessments to precision and accuracy. Results An ACCQ-TAG™ Ultra C18 (2.1 x 150 mm, 1.7µm, Waters Corporation) column with mobile phase compositions of 0.1% (v/v) formic acid in water and acetonitrile provided the highest resolution of all isobaric amino acids, including isoleucine and alloisoleucine (Rs 0.85). Under the devised gradient conditions of this method, which utilized a flow rate of 0.5 mL/min and column temperature of 55°C, all amino acids were eluted within a 17 min runtime. The optimized sample preparation and chromatographic conditions yielded an LC-MS/MS assay that was linear over a wide amino acid concentration range (5 to 1000 or 4000 µM, R>0.99) for all analytes. Average intra-day precision (N=10) of the low and high Kairos kit QC was 2.8% and 2.0%. The average inter-day precision (N=30) of this QC was 9.7% and 5.9%. LC-MS/MS derived plasma amino acid results had an acceptable bias relative to our current LC-UV method, with an average recovery of 113%. A blinded split sample analysis with a national reference laboratory also demonstrated good agreement, with an average plasma amino acid recovery of 102% relative to the reference laboratory mean. The accuracy of this protocol was further challenged by testing archived amino acid EQA material (N=7 samples) from ERNDiM. Good agreement relative to the ERDiM all method laboratory means were achieved, with amino acid (N=28) recoveries ranging from 93% (sulfocysteine) to 121% (glutamine) and a median recovery of 104%. Conclusion We have developed an accurate, precise and efficient LC-MS/MS meth","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"9 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-109 METALLOTHIONEIN AND ITS LEVELS DURING TREATMENT WITH PLATINUM-BASED CYTOSTATICS","authors":"Richard Prusa, Ondrej Mitrovsky, Ludek Melich, Matej Fusek, Jana Cepova, Rene Kizek","doi":"10.1093/clinchem/hvag086.424","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.424","url":null,"abstract":"Background Metallothionein (MT) is a low-molecular-weight intracellular protein whose primary function is heavy metal homeostasis. Several studies have already demonstrated a correlation between increasing MT concentrations in body fluids and cancer progression. The increased metabolic rate of cancer leads to higher consumption of metal ions. In cases where metal-based drugs are used for treatment, these MTs bind the drugs, subsequently leading to a decrease in therapeutic concentration. Methods Samples from patients following the administration of platinum cytostatics were analyzed in the experimental group. Patient anonymity was maintained at all times, and the entire study was approved by the Ethics Committee of Motol University Hospital. The observed group of evaluated data was from the years 2025–2026. A total of 20 probands were analyzed: 58 % female and 42 % male. The age range was from 16 to 81 years, with a mean age of 59 years (median 61 years). The frequency histogram clearly shows a skewness toward higher age categories. Electrochemical determination of MT was performed using the Brdicka reaction. Plasma was obtained from these probands and stored at -20 °C until processing. Samples were prepared according to our proposed procedure by thermal denaturation (99 °C, 20 min, 450 rpm). MT was determined via electrochemistry (differential pulse voltammetry, initial potential -0.7 V, final potential -1.85 V, scan rate 25 mV/s in Brdicka solution, 4 °C). For platinum analysis, GT-AAS determination was used (Pt 265.9 nm, lamp current 10 mA, argon flow 0.3 l/min, atomization 2850 °C, 1 s). Each studied sample was analyzed in 5 replicates. The obtained data were stored and processed in the laboratory information system QUINSLAB. Results During the optimization steps, the dependence on platinum concentration in plasma was studied. From the obtained data, a linear dependence of platinum concentration on absorbance was found (r = 0.9949). Analytical characteristics were calculated from all available data: LOD 40 ng/ml, LOQ 120 ng/ml, RSD up to 15%. In probands, concentrations upon drug administration were found between 2,000 – 1,500 ng/ml, and by 168 h, plasma concentrations were below the LOQ. MT levels were studied in these probands. The electrochemical study yielded MT voltammetric curves with typical signals (Cat1, Cat2, and Cat3). For each proband, the average curve was mathematically calculated and the area under the curve (AUC) was determined. Control sera from healthy probands (n = 40) were used to compare normal and abnormal MT levels, with a determined mean MT amount of 1.28±0.05 µg/l. In the group of probands, the mean MT amount at the time of cytostatic treatment administration was 18 ± 5.5 µg/l. During subsequent monitoring over time, MT levels gradually increased (by 20 – 80%) relative to the time since drug administration. Conclusion A pilot study was conducted focusing on monitoring the dynamics of platinum cytostatic levels and the","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"12 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-225 Plasma GFAP and NfL as biomarkers of disease classification and differential diagnosis in optic neuritis","authors":"Yuting Xue, Xiangyi Liu","doi":"10.1093/clinchem/hvag086.524","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.524","url":null,"abstract":"Background To test the hypothesis that plasma levels of glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL), which are an intermediate astrocyte and neuron filaments, respectively, are clinically useful biomarkers of disease classification and differential diagnosis in optic neuritis. Methods Levels of GFAP and NfL in plasma samples were measured in healthy controls (HCs) (n=45), patients with optic neuritis (ON) (n=79), and patients with ischemic optic neuropathy (ION) (n=25) by chemiluminescence immunoassay (CLIA). We also categorized ON patients into three subgroups based on the type of patient antibodies: AQP4-positive (n=54), MOG-positive (n=11), and AQP4 and MOG double-negative (DN) (n=14). Association of GFAP and NfL levels with clinical parameters was determined. Results In patients with optic neuritis, plasma GFAP levels were significantly higher in AQP4-positive patients than in patients who were double negative for AQP4 and MOG (p<0.05). GFAP levels were significantly higher in AQP4-positive optic neuritis patients than in AQP4-negative (MOG-positive as well as double antibody-negative) patients (p<0.05). NfL levels were higher in AQP4-negative optic neuritis patients compared with normal subjects (p<0.05); both GFAP and NfL levels were higher in AQP4-positive optic neuritis patients than in normal subjects (p<0.05). NfL levels were lower in patients with optic neuritis compared to those with ischemic optic neuropathy (p<0.05). NfL had good differential diagnostic efficacy between ischemic optic neuropathy and optic neuritis, with an area under the ROC curve of 0.828. Conclusion Plasma GFAP can be used to differentiate between AQP4-positive and AQP4-negative optic neuritis, and plasma NfL can be used as a potential biomarker for the differential diagnosis of optic neuritis and ischemic optic neuropathy.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"4 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-072 Synergy between SF Cube Technology and peripheral blood morphology: clinical impact on early diagnosis and prognosis in a case with Sézary Syndrome","authors":"Karla Cárdenas Cerdan, Nancy Herrera","doi":"10.1093/clinchem/hvag086.396","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.396","url":null,"abstract":"Background Sézary syndrome is a rare and aggressive leukemic variant of cutaneous T-cell lymphoma (CTCL), which primarily manifests in the skin before progressing systemically. It is classified as an orphan disease, accounting for up to 3% of all CTCL cases worldwide. Although precise epidemiological data in Latin America are limited, in Peru, the Instituto Nacional de Enfermedades Neoplásicas reported 74 cases of primary cutaneous T-cell lymphoma between 2008 and 2012, highlighting its rarity. The characteristic clinical and hematological triad includes erythroderma, generalized lymphadenopathy, and clonal Sézary cells in peripheral blood, skin, and lymph nodes. Due to its rapid progression, debilitating systemic involvement, and frequent delayed diagnosis, this malignancy is often initially misinterpreted as a benign dermatologic disease. We report a case evaluated using the Mindray BC-6800Plus hematology analyzer, whose findings contributed to the diagnosis of Sézary syndrome. Methods A 38-year-old male presented to outpatient consultation with a 4-month history of erythema of the hands and feet, initially treated as palmoplantar psoriasis without clinical improvement. Two months later, he developed generalized skin involvement associated with multiple lymphadenopathies and was referred with suspected chronic T-cell lymphoproliferative disorder for further evaluation. A peripheral blood sample was collected in a K2-EDTA tube. Complete blood count and leukocyte differential were analyzed using the Mindray BC-6800Plus analyzer. Peripheral blood smears were prepared and morphologically evaluated. Results The CBC revealed: red blood cells 4.11 × 10¹²/L; hemoglobin 126 g/L; hematocrit 37.3%; MCV 90.8 fL; MCH 30.6 pg; MCHC 338 g/L; RDW-CV 13.7%; RDW-SD 45.8 fL; platelets 235 × 10?/L; WBC 22.1 × 10?/L; lymphocytes 8.48%; monocytes 5.48%; eosinophils 0.57%; basophils 0.1%; neutrophils 33.9%; reticulocytes 1.93%; high-fluorescence cells (HFC) 0.1% and 0.01 × 10?/L. Analyzer flags included blasts, abnormal lymphocytes/blasts, monocytosis, lymphocytosis, and leukocytosis. The leukocyte scattergram in the DIFF channel showed a pathological population with increased fluorescence (FL) and heterogeneous side scatter (SSC), displacing the monocyte centroid and extending vertically into the lymphoid region. Peripheral blood smear examination demonstrated large atypical lymphocytes with convoluted, grooved “cerebriform” nuclei, intermediate to mature chromatin, occasional nucleoli, and scant cytoplasm. Conclusions The alerts and scattergram patterns generated by the SF Cube technology of the Mindray BC-6800Plus analyzer were highly suggestive of a pathological lymphoid population and prompted detailed morphological evaluation. Although diagnosis required a multidisciplinary approach with immunophenotyping for confirmation, accurate staging is essential for prognosis and therapeutic decision-making. Identification of Sézary cells allowed classification of the pa","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"20 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"B-018 Diagnostic Performance and Clinical Utility of the Sysmex HISCL Automated Plasma Amyloid-ß 1-42/1-40 Assay in a Real-world Setting","authors":"Seseung Kim, Joon Hee Lee, Seokryun Kwon, Kyunghoon Lee, Sang Mee Hwang, Sang Hoon Song, Junghan Song","doi":"10.1093/clinchem/hvag086.351","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.351","url":null,"abstract":"Background The escalating socioeconomic burden of dementia necessitates the development of accessible and cost-effective diagnostic tools for Alzheimer’s disease (AD). While cerebrospinal fluid analysis and positron emission tomography (PET) imaging are diagnostic gold standards, their invasiveness and high costs limit widespread utility. Blood-based biomarkers offer a scalable alternative, but clinical implementation requires automated platforms that balance sensitivity with the high throughput needed for routine laboratory settings. This study evaluated the diagnostic performance and clinical utility of the fully automated Sysmex HISCL plasma amyloid-ß (Aß) 1-42/1-40 assay (Sysmex Corporation, Kobe, Japan) in a real-world clinical setting Methods We retrospectively enrolled 127 participants, stratified into Cognitively Normal (CN, n=39), Mild Cognitive Impairment (MCI, n=46), AD (n=18), and Non-AD (n=24) subgroups. Plasma Aß42 and Aß40 levels were quantified using the HISCL-800 chemiluminescence enzyme immunoassay (CLIA) and compared with the Simoa® Neurology 4-Plex E (N4PE) assay (Quanterix, Billerica, MA, USA) and the AlzOn oligomerized Aß (OAß) assay (PeopleBio, Gyeonggi-do, Korea). Additionally, plasma glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were measured using the Simoa kit to evaluate combinatorial diagnostic models. To assess assay flexibility, we also evaluated analytical stability between matched heparinized and EDTA plasma samples. Results The HISCL plasma Aß42/40 ratio was significantly lower in the AD continuum (MCI+AD) compared to the CN subgroup (P < 0.001) and the Non-AD subgroup (P = 0.0099). In Receiver Operating Characteristic (ROC) curve analysis, the HISCL assay demonstrated robust diagnostic performance (AUC=0.747), which was significantly superior to the OAß assay (AUC=0.523) and numerically higher than the Simoa Aß42/40 ratio (AUC=0.687). Although method comparison revealed a proportional difference between platforms, an analysis of discordant cases indicated that the Simoa assay frequently classified CN and Non-AD participants as positive. Specifically, 87% of Simoa-positive/HISCL-negative cases belonged to non-AD groups, suggesting that HISCL may offer better specificity in real-world screening contexts. Notably, integrating plasma GFAP and NfL with the HISCL Aß42/40 ratio significantly enhanced diagnostic accuracy, achieving an AUC of 0.823 (P = 0.046). Furthermore, the HISCL assay exhibited high stability across sample types, showing a regression slope near unity between heparinized and EDTA plasma. Conclusion The fully automated HISCL plasma Aß42/40 assay demonstrates reliable diagnostic performance for identifying AD pathology, effectively distinguishing the AD continuum from cognitively normal controls and non-AD dementias. Its analytical stability, high throughput, and automation capability support its feasibility for routine clinical practice. Moreover, the significant im","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"22 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}