Clinical chemistry最新文献

{"title":"A-240 Multicenter Performance Evaluation and Method Comparison of the Yumizen H550 Hematology Analyzer","authors":"Amin Mohammad, Azar Khatibi, Joanna Hipolito, Susan Behnke, Andrea Torres, Amber Jones","doi":"10.1093/clinchem/hvag086.192","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.192","url":null,"abstract":"Background Accurate hematological analysis is critical for clinical decision-making across diverse patient populations. This study evaluates the performance of the Yumizen H550, a compact hematology analyzer, by comparing it to the established Yumizen H2500 predicate device. The evaluation aimed to validate the H550’s accuracy across a broad analytical measuring range, including both normal and pathological samples. Methods A multicenter study was conducted at three clinical sites: Baylor Scott & White Medical Center (Texas, US), Columbia University Medical Center (New York, and CHU Nîmes (France). Following CLSI EP09c guidelines, at least 250 specimens were analyzed at each site, totaling over 750 samples. The study included adult and pediatric subjects (neonate to <22 years), utilizing both venous and capillary whole blood samples collected in K2EDTA. Samples were analyzed in DIF mode on both the Yumizen H550 and H2500 within established stability timeframes. Data analysis was performed using Passing-Bablok regression to estimate bias and correlation for CBC and differential parameters. Results The Yumizen H550 demonstrated strong correlation with the H2500 across all primary parameters, including White Blood Cells (WBC), Red Blood Cells (RBC), Hemoglobin (HGB), Hematocrit (HCT), and Platelets (PLT). Summary data indicated that the H550 met all pre-defined acceptance criteria for method comparison. Predicted bias at critical medical decision points for parameters such as HGB, MCV, and Neutrophil absolute counts remained within clinically acceptable limits. The analyzer effectively identified various pathologies, including leukocytosis, anemia, and thrombocytopenia, as well as abnormal cell types like schistocytes and immature granulocytes. Conclusion The Yumizen H550 shows excellent analytical agreement with the high-throughput Yumizen H2500 platform. Its robust performance across diverse age groups and pathological conditions confirms its suitability for clinical laboratory environments requiring reliable, low-to-mid volume hematology testing.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"30 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086424","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-404 Determinants of Analytical Performance in Centrifugation–Based Hematocrit: Effects of Calibration and Internal Quality Control Frequency Across Hospital and Primary Point-of-Care Sites","authors":"Wanvisa Treebuphachatsakul","doi":"10.1093/clinchem/hvag086.328","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.328","url":null,"abstract":"Background Manual centrifugation–based hematocrit (Hct) remains widely used as point-of-care testing (POCT) in hospital laboratories and subdistrict health promotion hospitals (SDHHs), particularly in decentralized settings. However, evidence is limited on whether quality-related factors influence satisfactory performance when evaluated using both precision (z-score) and trueness (bias%). This study aimed to determine whether calibration status, reading types, participation in external quality assessment (EQA), and internal quality control (IQC) frequency were associated with satisfactory performance in both settings. Methods A multicenter analysis included six reference blood materials (68-Hct001–006) tested by hospital laboratories and SDHH POCT sites. Z-scores were calculated using group-specific robust means determined by Algorithm A (ISO 13528). Bias% was calculated against target values derived from the mean results of three reference laboratories in accordance with ISO Guide 35. All blood materials were produced by an ISO 17034–certified reference material producer. Satisfactory performance was defined as |z|=2 and bias thresholds of =6% and the stricter =4%. Associations were evaluated using Chi-square analysis. Results Hospital laboratories demonstrated higher satisfactory performance than SDHH sites across all samples, with the largest differences observed when accuracy was assessed using bias% =4%. Calibration was significantly associated with improved accuracy in both settings (?² = 12.4, p < 0.001). Increased IQC frequency was associated with improved precision in hospital laboratories (|z|=2; ?² = 4.9, p = 0.027) but showed no significant association in SDHH sites. Performance classification differed between z-score– and bias%-based evaluations, with larger between-setting differences observed when the bias =4% criterion was applied compared with z-score–based evaluation. Conclusion Calibration and IQC frequency were associated with satisfactory performance. However, their effects varied depending on the performance metric and assigned value approach. Use of target values with a strict bias criterion (=4%) resulted in different performance classification compared with z-scores based on group-specific robust means, underscoring the importance of assigned value definition when interpreting performance outcomes, particularly for SDHH POCT sites.","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":"149086425","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-285 Underdiagnosis and Gaps in Guideline-Recommended Testing for Chronic Kidney Disease in an Academic Health System: A Population-Based Race, Ethnicity, Language, and Sex Analysis","authors":"Zhengchun Lu, Yunpeng Lyu, Siouxzanna Downs, Raghav Wusirika, Vanderlene Kung, Guang Fan","doi":"10.1093/clinchem/hvag086.569","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.569","url":null,"abstract":"Background Chronic kidney disease (CKD) is underdiagnosed, and adherence to National Kidney Foundation (NKF) screening recommendations among high-risk patients remains suboptimal. NKF guidelines recommend annual assessment with both estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (uACR) among patients with diabetes or hypertension. We evaluated CKD diagnosis, risk burden, and testing gaps using the NKF CKD framework, stratified by race, ethnicity, language, and sex variables. Methods We conducted a retrospective population-based analysis of 407,894 adults aged 18–85 years with at least one clinical encounter in the Oregon Health & Science University (OHSU) health system between January 1 and December 31, 2025. CKD diagnosis was identified using ICD-10 codes. High-risk status was defined as diabetes and/or hypertension. Guideline-concordant testing was defined as completion of both eGFR and uACR within 12 months. Laboratory-identified CKD was defined as an eGFR <60 mL/min/1.73 m² on at least two measurements separated by =90 days in the absence of a documented CKD diagnosis. Results Overall, 5.01% (20,450/407,894) of adults had a documented CKD diagnosis, with prevalence increasing markedly with age (0.73% ages 18–35; 2.90% ages 35–65; 10.88% ages 65–85). Documented CKD prevalence differed by sex, with lower prevalence among males (4.12%, 9,746/236,766) compared with females (6.26%, 10,701/170,911). Race, and language information was largely disclosed but not complete. Race was documented for 93.84% of patients (382,776), while 5.01% (20,450) declined disclosure and 1.14% (4,668) had unknown race. Ethnicity was disclosed for 88.29% (360,124) patients, with 11.71% (47,770) declining or missing. Language preference was undocumented for 4.8% (19,664) patients. Across race, and language strata, patients with unknown demographic information consistently ranked lowest for guideline-concordant testing completion (Table 1). Among patients without a CKD diagnosis (n=387,444), 24.0% (92,946) had diabetes and/or hypertension, yet only 11.30% (10,501/92,946) completed guideline-concordant co-testing (eGFR and uACR) within 12 months. Completion was lowest among patients with hypertension alone (2.28%, 1,301/57,134). Additionally, 3,141 patients met laboratory criteria for CKD without a documented diagnosis; most were male (59.97%,884/3,141) and aged =65 years (70.8%, 2,225/3,141). Among all patients with diagnosed or laboratory-identified CKD (n=23,591), only 16.19% (3,820) had uACR measured in the prior 12 months. Conclusion Substantial gaps persist in CKD recognition and guideline-recommended testing, particularly among high-risk patients. Incomplete documentation of race, and language is common, and lower completion of guideline-concordant testing is consistently observed among these patients. System-wide strategies incorporating automated laboratory triggers, standardized uACR ordering, and improved demographic ","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"142 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086430","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-402 Development of a Rapid Multiplex LC-MS/MS Assay for Therapeutic Drug Monitoring of Antituberculosis Drugs and Metabolites","authors":"Hannah Lusk","doi":"10.1093/clinchem/hvag086.669","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.669","url":null,"abstract":"Background Tuberculosis (TB) remains a major public health concern that disproportionately affects medically complex and vulnerable populations. In San Francisco, TB incidence is 6.9 cases per 100,000 persons compared to 2.2 per 100,000 nationally, and all cases are managed through the San Francisco Department of Public Health Tuberculosis Clinic, which treats a predominantly older population with high rates of comorbidities and increased risk for drug toxicity/treatment complications. Approximately 30% of patients require treatment interruption or discontinuation due to adverse drug reactions, often resulting in prolonged therapy and increased morbidity. Therapeutic drug monitoring (TB-TDM) is increasingly used to optimize dosing and reduce toxicity; however, its clinical utility remains limited by delayed turnaround times, discordant results between laboratories, and incomplete pharmacokinetic assessment. TB-TDM in the United States is performed at only two reference laboratories, requiring specimen shipment and resulting in turnaround times of several weeks, delaying dose adjustments and clinical decision-making. Additionally, existing methods measure only parent drug concentrations and do not quantify metabolites or degradation products, limiting assessment of drug metabolism, adherence, and sample integrity. These limitations represent a significant barrier to effective TB-TDM and highlight an unmet clinical need. Methods A quality improvement study evaluated concordance of TB drug concentrations measured by two commercial reference laboratories. To address identified limitations, we developed a multiplex hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC LC-MS/MS) assay using a Waters Acquity BEH amide column coupled to a SCIEX 4500 triple quadrupole mass spectrometer. The assay simultaneously quantifies 12 analytes including first-line drugs (rifampin, isoniazid, pyrazinamide, ethambutol), metabolites (25-desacetyl-rifampin, N-acetyl-isoniazid), degradation products (rifampin quinone), and second-line therapeutics (rifapentine, rifabutin, linezolid, bedaquiline, pretomanid). Serum samples underwent protein precipitation and dilution prior to analysis. Chromatographic separation was achieved using ammonium formate and acetonitrile mobile phases in a 5-minute runtime. Preliminary validation was performed according to CLSI and FDA bioanalytical method validation guidelines. Results Concurrent testing at commercial laboratories demonstrated clinically significant discordance in rifampin and isoniazid serum concentrations, highlighting limitations of current TB-TDM practices and risk for inappropriate dose adjustments. The HILIC LC-MS/MS assay achieved chromatographic separation of all analytes within 5 minutes despite wide polarity differences. Preliminary validation demonstrated acceptable analytical performance. Accuracy bias ranged from -0.9% to 4%. Limits of quantification were 0.6–7.5 µg/mL, encompassing therape","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"8 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086431","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-347 MMP-7 as an effective biomarker for ruling out biliary atresia","authors":"Chris Streicher, James Rose, Thelma Kathman, Erin Schuler","doi":"10.1093/clinchem/hvag086.282","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.282","url":null,"abstract":"Background The nephrology clinical lab at Cincinnati Children’s Hospital Medical Center has recently validated a diagnostic test to quantify matrix metalloproteinase-7 (MMP-7) in human serum/plasma. MMP-7 also known as uterine metalloproteinase is an enzyme that is key in the breakdown of extracellular macromolecules and has shown promise as a biomarker for the detection of several pathologies. In infants, MMP-7 is has been demonstrated as a potential biomarker for biliary atresia (BA). BA is a liver disorder occurring in babies where bile ducts become blocked and prevent appropriate excretion from the liver. BA must be treated with a hepatoportoenterostomy (Kasai procedure) to fix the blockage. Early detection and surgery have been correlated with improved clinical outcomes and longer life of their natural liver. Currently, biopsy is the gold standard for detection of BA. MMP-7 offers a non-invasive alternative to rule out BA when evaluated in a high-risk patient population. Methods Validation was completed on the fully automated DZ-Lite MMP-7 chemiluminescent immunoassay (CLIA) kit on the Diazyme DZ-Lite 3000 Plus for determination of MMP-7 concentration. This kit uses an ABEI labeled anti-MMP-7 polyclonal antibody and magnetic microbeads coated with anti-MMP-7 monoclonal antibody for capturing. Specimens are mixed with the capturing and detecting reagents to form a sandwich complex at 37 ° C. After sedimentation, the sample is washed to remove unbound substances. Starter reagents containing diluted NaOH and H2O2 are added and begin the flash chemiluminescent reaction. The light signal produced is directly proportional to the concentration of MMP-7 in the sample. Statistical analysis was performed in EP evaluator. Results All performance metrics were evaluated against a total allowable error of 4 ng/mL or 20 %. The analytical measuring range was determined to be 0.4 ng/mL to 26.4 ng/mL. Age dependent reference ranges were determined from peer-reviewed publication or manufacturer claim, and each range was verified by assaying normal serum samples. The normal MMP-7 concentration range for ages 0-30 days was 4.6-23.8 ng/mL based on 36 samples tested, for 31-150 days the normal range was determined to 3.4-14.3 ng/mL based on 22 samples, and for =151 days the normal ranges was 0.2-5.4 ng/mL based on 116 samples. The cutoff for BA was determined from an ROC analysis using 8 confirmed positive BA cases obtained via the Kasai biopsy procedure. MMP-7 concentrations below the established cutoff of 28.8 ng/mL for the age range between 0-30 days and MMP-7 concentrations under the cutoff of 18.5 ng/mL for ages between 30-150 days effectively ruled out BA. Conclusion MMP-7 is an effective screening test for BA in newborns and infants. Having an automated, clinically validated CLIA kit available as a screening test allows for an efficient, non-invasive and cost-effective methodology to rule out BA.","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":"149086473","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-293 Sustainability Through the Implementation of Evidence-Based Equations: A Pilot Study using the Friedewald and NIH-Sampson Equations","authors":"Stephanie Hart, Joe Wiencek","doi":"10.1093/clinchem/hvag086.238","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.238","url":null,"abstract":"Background Low-density lipoprotein cholesterol (LDL-C) is an important metric for risk stratifying cardiovascular disease and therapeutic monitoring. The gold standard for measuring LDL-C is beta-quantification. However, most laboratories utilize the 1972 Friedewald equation to calculate LDL-C from measured total cholesterol, high-density lipoprotein, and triglycerides (TG). Patients with TG >400 mg/dL are a known limitation of the calculation and must be reflexed to a direct LDL-C (DLDL) measurement on an automated chemistry analyzer. More recently, the evidence-based NIH-Sampson equation became an alternative. It was derived from a multiple least squares regression to calculate LDL-C for patients with TG up to 800 mg/dL. This study investigated the potential environmental, laboratory and patient savings of implementing the new NIH-Sampson equation. Methods Our institution reports the calculated LDL-C using the Friedewald equation with the intent to switch to the NIH-Sampson equation. Currently, DLDL is measured on the Abbott Alinity c or Roche cobas 503 platforms for patients with TGs >400 mg/dL at either our hospital or reference laboratories, respectively. To understand potential savings, total lipid panels resulted and associated results were collected from January to December 2025. Reagent costs for DLDL assays for both sites were determined by the laboratory (reagent cost/test). The weight of both non-recyclable reagent cartridges was measured in grams and patient charges for the lipid panel and DLDL assays were provided by the institution’s billing department. Results A total of 144,041 lipid panels resulted in 2025 (hospital: 39,737; reference: 104,304). Of the lipid panels performed, patient TG were >400 mg/dL in 3.3% (n=1,296) and 1.6% (n=1,663) resulting in a reflex DLDL assay at the hospital and reference laboratories, respectively. If our institution were to replace the Friedewald equation with the NIH-Sampson equation, 1,785 DLDL tests could be eliminated at both sites from patients with TG between 400-800 mg/dL (hospital: 727, reference: 1,058). The hospital reagent cartridge produces 77.5 g of non-recyclable waste whereas the reference laboratory reagent produces 35.3 g. This could result in a total reduction of 225.6 g (hospital: 155 g, reference laboratory: 70.6 g) of non-recyclable reagent waste at the hospital and reference laboratories. In addition, the institution would save a total of $1480.54 in hospital reagent costs ($2.04/test) and $1,595.46 in reference laboratory reagent costs ($1.51/test). Patients are currently charged $161 per lipid panel and an additional $79 for the reflex DLDL assay. The elimination of DLDL assays for patients with triglycerides between 400-800 mg/dL amounts to $141,015 of patient charge savings. Conclusion Our study demonstrates switching to the NIH-Sampson equation for calculating LDL-C would decrease the environmental impact, laboratory costs, and overall patient healthc","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"171 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086479","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-245 Robust Performance of the Quantra® Hemostasis Analyzer in Global Proficiency Testing","authors":"Nat Sherwood","doi":"10.1093/clinchem/hvag086.196","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.196","url":null,"abstract":"Background Both CLIA and CAP mandate biannual proficiency testing, which assesses the accuracy and reliability of a methodology. Coagulation proficiency testing aims to routinely monitor a diagnostic analytical method via blind sample testing by a trained user with demonstrated competency. Resulting data is then analyzed against a peer group to determine proficiency. Fulfillment of PT quality standards, backed by comprehensive statistical analysis, ensures accurate, reliable methodology directly correlating to patient safety. The required use of whole blood samples in conventional coagulation proficiency testing poses challenges for interpretation of statistical inter-laboratory comparison due to naturally occurring donor-to-donor variation in coagulation characteristics. Methods An External Quality Assessment (EQA) commensurate to regulatory proficiency testing requirements was developed using alternative, controlled test materials to enable a more robust, comprehensive statistical analysis across all participants. Lot-specific material was incorporated into the annual assessment, maintaining the tenets of biannual, blind-sampled proficiency testing structure. To ensure the structure satisfied laboratory proficiency testing performance needs, the EQA’s procedure mirrored that of a core device operational element. This EQA design facilitated two metrics of comprehensive statistical analysis not afforded by the conventional method: Youden Plot and Z-Score. These analyses afford quantitative insight into both intra-laboratory execution and comparative inter-laboratory performance. Results Between 126-129 data points were collected for each of the four QPlus Cartridge parameters across 74 global participating sites in 2024. Results for all parameters (CTH, CT, CS, FCS) demonstrated an average coefficient of variation (CV) of 5.5% and CVs as low as 3.7% across all specimen compositions (Table 1). An average Z-Score of 0.008 was achieved across these four parameters by all US 2024 EQA participants. In alignment with published criteria, target values for each parameter were equal to the peer group mean. The peer group surpassed sample size requirements following removal of outliers, and result assessment was successfully executed based on an acceptability range defined by the target value ± three standard deviations. Conclusion This EQA with optimized material composition provided a robust statistical peer-to-peer analysis for proficiency testing participants using the Quantra Hemostasis System method in a clinical laboratory or POC setting. Extensive statistical evaluation yielded high precision outcomes, enabling increased confidence in the Quantra method, the reagent quality of the QPlus Cartridge, and overall user proficiency. The substantial participant volume afforded by a global audience enhanced credibility, and therefore reliability, in the results produced by the Quantra Hemostasis System.","PeriodicalId":10690,"journal":{"name":"Clinical chemistry","volume":"91 1","pages":""},"PeriodicalIF":9.3,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086496","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-230 Establishing an Optimal HIT Optical Density Value: A Six Year Study","authors":"Cate Hoesl, Atef Shrit, Paul Riley, Joffrey Feriel","doi":"10.1093/clinchem/hvag086.186","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.186","url":null,"abstract":"Background Our core laboratory provides Heparin Induced Thrombocytopenia antibody (HIT) laboratory screening to patients across our health system. Our enzyme-linked immunosorbent assay (ELISA) format can be reported using a Positive or Negative result and in raw optical density (OD) units. We validated an optimal HIT OD value for our providers that correlated with a positive HIT confirmatory assay result. Reporting the HIT OD value can bring greater confidence to clinicians, since a high HIT OD value strongly correlates to positive HIT confirmatory value by serotonin release assay (SRA), especially if the patient’s clinical score (i.e. 4Ts Score) is intermediate or high. Methods A polyspecific (IgG, IgM, IgA) HIT test using ELISA methodology was used for HIT screening (Asserachrom HPIA, Diagnostica Stago, Inc., Parsippany NJ, USA). HIT OD values were determined using a a VersaMax Microplate reader at a wavelength of 450 nm. Six years of positive HIT OD patient data was analyzed for mean average OD value, distribution of the OD values across the positive reportable range, and correlation with Serotonin Release Assay (SRA) results. ROC data analysis was performed for determination of the optimal HIT OD cutoff correlating with positive confirmatory SRA result. Results We determined a HIT OD of 1.281 with an optimal sensitivity of 85.7% and specificity of 82.7%. Conclusion A HIT OD value was determined with peak sensitivity and specificity versus a positive SRA value. Since SRA testing often takes days to complete at an outside reference laboratory, having an optimal HIT OD value can better predict a positive SRA result and can help diagnose HIT with a faster turnaround time, allowing for better patient management and therefore potential improved patient outcomes.","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":"149086510","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-083 Rapid screening for acute chikungunya virus infection using an interpretable machine learning model based on routine complete blood count parameters.","authors":"Yan Liu, Dongde Xie, Guobiao Zhang, Yongkun Lai","doi":"10.1093/clinchem/hvag086.061","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.061","url":null,"abstract":"Background The 2025 Chikungunya virus (CHIKV) outbreak in Foshan, China, highlighted an urgent need for rapid screening tools. Molecular diagnostics are constrained by time, cost, and availability. This study aimed to develop and validate an interpretable machine learning model using routine complete blood count (CBC) parameters to identify patients at high risk of CHIKV infection. Methods A retrospective cohort study was conducted on 1,537 suspected CHIKV patients from two medical centers in Foshan. CBC and cell population data (CPD) were obtained using Mindray BC-7500 analyzers. CHIKV infection was confirmed by reverse transcription polymerase chain reaction (RT-PCR). After rigorous data preprocessing and feature selection using LASSO regression, four models Logistic Regression (LR), Support Vector Machine (SVM), Random Forest (RF), and LightGBM (LGBM) were developed on a training set (n=1,132 from Center A) and evaluated on an internal test set (n=192) and an independent external test set (n=213 from Center B). Model performance was assessed by the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and net benefit. Results In the external validation set, the LR model demonstrated superior and robust performance (AUC = 0.807, sensitivity = 88.0%, specificity = 65.0%, NPV = 93.0%), significantly outperforming the tree-based models. Decision curve analysis confirmed its clinical utility across a wide range of risk thresholds. SHAP analysis revealed that lower white blood cell count (WBC_N), lower lymphocyte percentage (Lym%), and increased neutrophil morphological heterogeneity (D_Neu_SSC_CV) were the strongest predictors, aligning with the established pathophysiology of CHIKV infection. Conclusion We developed an interpretable LR model based on CBC parameters that can effectively screen for acute CHIKV infection with high sensitivity and NPV. This model serves as a reliable, rapid, and cost-effective tool for patient triage during outbreaks, especially in resource-limited settings awaiting confirmatory PCR testing.","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":"149086531","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-223 Early Recognition of Thrombotic Thrombocytopenic Purpura Using the Mindray BC-6800Plus Hematology Analyzer in a Low-Incidence Setting in Peru: A Case Report","authors":"Michael Baron","doi":"10.1093/clinchem/hvag086.179","DOIUrl":"https://doi.org/10.1093/clinchem/hvag086.179","url":null,"abstract":"Background The High-Complexity Hospital Virgen de la Puerta – EsSalud La Libertad in Trujillo, Peru, is a specialized center for the diagnosis and management of complex medical conditions. Thrombotic Thrombocytopenic Purpura (TTP) is a very rare and life-threatening hematologic disorder, with an estimated global incidence of 4–5 cases per million people per year. There are no official records that accurately detail the incidence of TTP in Trujillo or nearby areas. The diagnosis of TTP is primarily based on clinical suspicion of thrombotic microangiopathy, confirmed by the triad of severe thrombocytopenia, microangiopathic hemolytic anemia (with schistocytes), and ADAMTS13 enzyme activity below 10%. Methods A 32-year-old male patient from Chimbote, presented with petechiae on the arms and back, accompanied by general malaise. His Glasgow Coma Scale score was 15. Later, scleral and palmar jaundice appeared, along with nausea and vomiting. The patient subsequently became encephalopathic, with incoherent speech. A whole blood sample was collected in a K2-EDTA tube for complete blood count analysis using the Mindray BC-6800Plus hematology analyzer. Scattergrams, histograms, and cytograms were evaluated, and a peripheral blood smear (PBS) was reviewed. Other biochemical analyses were also performed as part of the evaluation protocol. Results Liver and spleen were normotrophic. Laboratory findings: Coagulation times were within normal limits, and d-dimer was 0.89 µg/mL. Blood group and Rh factor: A1 Rh positive, and direct Coombs test was negative. Total bilirubin 8.58 mg/dL, direct bilirubin 0.58 mg/dL, glucose 126 mg/dL, creatinine 0.96 mg/dL, urea 43 mg/dL, LDH 3,337 IU/L. Hematocrit 22.7%, hemoglobin 7.8 g/dL, platelets 7,000/mm³, and IMG 3%. PBS revealed anisocytosis 1+, polychromatophilia 3+, schistocytes 3+, and spherocytes 1+. Fourteen normoblasts per 100 leukocytes were observed. Reticulocyte count was 17%, RBC fragments 1.21%, and reticulocyte production index (RPI) 4.1. Analyzer alarms included: Abnormal lymphocytes/blasts, immature granulocytes, presence of NRBC, lymphopenia, anemia, RBC fragments, abnormal RET scattergram, reticulocytosis, abnormal platelet histogram, and thrombocytopenia. The DIFF scattergram showed high-fluorescence cells above neutrophils compatible with IMG and low-fluorescence cells below lymphocytes, which correlates with NRBC. In the RET scattergram, an increase in fragments and immature red blood cells with intermediate to high fluorescence corresponding to reticulocytosis was observed. Peripheral smear review confirmed the presence of schistocytes and marked thrombocytopenia. Conclusion This case highlights the importance of having diagnostic tools capable of identifying unlikely clinical conditions in small localities such as this city in Peru. The Mindray BC-6800Plus analyzer, which uses optical and fluorescence-based methodology for cell counting, was of critical value, especially in differentiating platelets fr","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":"149086541","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}