Journal of Applied Laboratory Medicine最新文献

{"title":"Leveraging Taylor Approximation-Based Decomposition of Clot Waveform Data to Advance Clinical Coagulation Testing.","authors":"Maximo J Marin","doi":"10.1093/jalm/jfag067","DOIUrl":"https://doi.org/10.1093/jalm/jfag067","url":null,"abstract":"","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":"11 5","pages":"1306-1310"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148889130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Total Serum Calcium Spike-Recovery Experiments to Investigate Bones of Contention in Clinical Laboratories.","authors":"Sarah L Davies, Rachel Marrington, Iryna Mikheenko, Khadan Mohamed, Finlay MacKenzie","doi":"10.1093/jalm/jfag059","DOIUrl":"10.1093/jalm/jfag059","url":null,"abstract":"<p><strong>Background: </strong>To help assess patient safety risks associated with ongoing differences in total calcium assays following bias shifts, we performed spike-recovery experiments within our clinical chemistry external quality assessment (EQA) schemes to evaluate bias and recovery against a reference measurement procedure (RMP).</p><p><strong>Methods: </strong>Aqueous calcium chloride dihydrate was spiked (0.30/0.60 mmol/L; 1.20/2.40 mg/dL) into pooled human serum. Bias was assessed against RMP-assigned targets and recovery against added spikes. Minimum analytical performance specifications (APS) for standard measurement uncertainty (1.36%) defined acceptable bias/recovery.</p><p><strong>Results: </strong>Commercially available analytical principles across analytical platforms did not achieve adequate bias against RMP-assigned targets and recovery against added spikes for total calcium in 3 EQA specimens. Roche Cobas (5-nitro-5'-methyl-1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid [NM-BAPTA]), Roche Cobas Pro (NM-BAPTA), and Beckman AU (Arsenazo III) methods exhibited better bias and long-term stability. The Abbott Alinity (Arsenazo III) method exhibited notable negative bias (-2.33% to -3.10%), apparently coinciding with the introduction of Abbott Calcium2. Negative bias was present to a lesser extent in the Abbott Architect (Arsenazo III). The Siemens Atellica (cresolphthalein complexone) assay exhibited notable proportional over recovery (110.2% to 112.0%). There was some positive bias in the Siemens Atellica (Arsenazo III) and QuidelOrtho (dry slide/sensor) methods.</p><p><strong>Conclusions: </strong>Differences across analytical principles/platforms and difficulties achieving minimum APS for total calcium were shown within our EQA schemes, notably negative bias for Abbott Alinity and Architect (Arsenazo III), over-recovery for Siemens Atellica (cresolphthalein complexone) and positive bias for Siemens Atellica (Arsenazo III). Understanding the impact on clinical decision-making and patient outcomes is imperative for managing any patient safety risks.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1093-1107"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147976303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical Performance of the Sixth Generation High-Sensitivity Cardiac Troponin T Assay.","authors":"Mengyuan Ge, Lori B Daniels, Spencer Seely, Ronald W McLawhon, Robert L Fitzgerald, Raymond T Suhandynata","doi":"10.1093/jalm/jfag055","DOIUrl":"10.1093/jalm/jfag055","url":null,"abstract":"<p><strong>Background: </strong>High-sensitivity cardiac troponin assays are integral to diagnosing myocardial infarction. The current Roche Elecsys® Troponin T high-sensitivity Gen 5 assay (Gen 5) received FDA clearance in 2017. A sixth-generation assay was recently developed with improved analytical characteristics, including sensitivity and resistance to interferences. Reference ranges for this assay were reported, but analytical performance in the clinical laboratory has yet to be evaluated.</p><p><strong>Methods: </strong>The Elecsys® Troponin T high-sensitivity Gen 6 (Gen 6) assay was evaluated on the Roche cobas e 801 analyzers. Measurement limits of the assay were determined in lithium-heparin plasma specimens per CLSI EP17-A2. Repeatability and intermediate precision of QC materials and plasma specimens were determined according to CLSI EP05-A2 and EP15-A2, respectively.</p><p><strong>Results: </strong>Serial dilutions of cardiac troponin T revealed that Gen 6 exhibits a positive bias relative to Gen 5 at concentrations >10 ng/L. Below this point, the bias reverses, indicating concentration-dependent crossover. The limit of blank and limit of detection were 0.4 ng/L and 1.2 ng/L, respectively. The limit of quantitation was 2.2 ng/L with a 10% CV. No cross-reactivity was observed on Gen 6 for skeletal muscle troponin T, cardiac troponin I, skeletal muscle troponin I, or troponin C at concentrations up to 10 000 ng/L. Interference from hemolysis was not observed up to 5000 mg/dL of hemoglobin.</p><p><strong>Conclusions: </strong>The Gen 6 assay demonstrates resistance to interference and greater analytical sensitivity, with a lower limit of detection and limit of quantitation relative to Gen 5, enabling broader coverage of healthy individuals.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1026-1038"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148206534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pediatric Glucose-6-Phosphate Dehydrogenase Reference Intervals Derived from Archived Phenotype and Genotype Test Results.","authors":"Kwaku Baryeh, Kelly Doyle","doi":"10.1093/jalm/jfag076","DOIUrl":"10.1093/jalm/jfag076","url":null,"abstract":"<p><strong>Background: </strong>Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most prevalent global enzymopathy with risks of hemolytic anemia and hyperbilirubinemia. G6PD activity peaks at birth and decreases during the first year of life. Therefore, partitioned reference intervals (RI) are important for diagnosing G6PD deficiencies in pediatric patients. Given the paucity of pediatric RIs and difficulties in direct sample collection from healthy children, indirect RI methods were utilized to evaluate RIs for G6PD activity in this population. We established accurate RIs and percentage of normal activity thresholds (PNAT) for G6PD activity in children using refineR and genotype data.</p><p><strong>Methods: </strong>G6PD activity (U/g Hb) from patients <18 years old tested in our laboratory were used to derive RIs and PNATs. refineR with 1-parameter Box-Cox transformation was used to determine RIs and medians for PNATs. Bootstrapping was used to calculate confidence intervals for the estimated RIs. Retrospective analysis of G6PD activity results and correlating G6PD genotypes, were used to verify the estimated RIs and PNATs.</p><p><strong>Results: </strong>Age-partitioned 2.5th, 50th, and 97.5th percentiles (point estimate, U/g Hb) for children were established from a dataset of 32 576 results <8 days (16.4, 19.9, 24.1), 8-<31 days (13.6, 18.2, 23.9), 1-<7 months (11.5, 16.2, 21.5), 7-<13 months (10.3, 13.7, 17.9), and 1-<18 years (9.7, 12.9, 16.9). Alignment of RIs and PNATs with genotype classification (n = 105) showed 96% and 93% agreement, respectively, in unaffected, heterozygous, and deficient individuals across age groups.</p><p><strong>Conclusions: </strong>Indirect RIs for G6PD in children from a noncurated real-world dataset showed strong alignment with genotype classification.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1050-1063"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148158607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of TIMP1, Transgelin-2, and Procalcitonin as Protein Biomarkers for Diagnosis and Prognosis of Bloodstream Infection in a Critically Ill Cohort.","authors":"Sajal Tiwary, Caroline A O'Neil, Sydney Lawless, Olivia Arter, Meghan Brown, Brittany Roemmich, Carleigh Samuels, Jennie H Kwon, Christopher W Farnsworth","doi":"10.1093/jalm/jfag084","DOIUrl":"10.1093/jalm/jfag084","url":null,"abstract":"<p><strong>Background: </strong>Bloodstream infections (BSI) are a significant contributor to morbidity and mortality among hospitalized patients. Rapid diagnosis of BSI is critical for timely and appropriate clinical management, but current diagnostic strategies have a prolonged turnaround time or only identify select pathogens with minimal prognostic information.</p><p><strong>Methods: </strong>We examined serial serologic samples from 77 intensive care unit (ICU) patients at time points before, during, and after diagnosis of presumptive BSI to identify host-derived protein biomarkers associated with specific organisms and with clinical outcomes in BSI. ICU patients with and without BSI were included. Two candidate biomarkers, tissue metalloproteinase 1 (TIMP-1) and transgelin-2 (transgelin), were analyzed using enzyme-linked immunosorbent assay (ELISA) analysis and with procalcitonin (PCT) as a positive control.</p><p><strong>Results: </strong>TIMP-1 was higher in those with gram-negative BSI [median = 746 ng/mL, interquartile range (IQR): 355-1410] than gram-positive BSI (662 ng/mL, 396-1111), and culture negative (377 ng/mL, 189-708). For transgelin, those with gram-negative BSI were highest (14.6 ng/mL, 9.6-22.0), followed by gram-positive BSI (9 ng/mL, 6.1-16), and negative cultures (9.1 ng/mL, 5.6-13.0). PCT was highest among patients with gram-positive BSI (10.8 ng/mL, 1.3-23.3), followed by gram-negative BSI (7.7 ng/mL, 1.6-57.7), and negative cultures (1.2 ng/mL, 0.3-3.5). The multiplicative product of all 3 markers had an AUC of 0.8 (0.7-0.9). No biomarker was associated with risk for ICU admission, 30-day mortality, or length of stay.</p><p><strong>Conclusion: </strong>TIMP1 and transgelin-2 are candidate biomarkers for diagnosing BSI. Larger studies comparing their utility to PCT and other sepsis biomarkers are warranted.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1064-1077"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148220162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Current State and Needs of Clinical Laboratories in Selected Countries in Africa.","authors":"Merih Tesfazghi, Anne E Tebo, Roa Harb, Anthony O Okorodudu, Lee Schroeder, Jeannette Guarner, Christine Bales, Jack Ladenson, Allison Targowski, Kerry Cosby, Olajumoke Oladipo","doi":"10.1093/jalm/jfag089","DOIUrl":"10.1093/jalm/jfag089","url":null,"abstract":"<p><p>The Africa Working Group, under the auspices of the Global Laboratory Quality Initiative of the Association for Diagnostics & Laboratory Medicine (ADLM), conducted several educational workshops in Africa to promote laboratory quality in the region. The challenges faced in maintaining quality in clinical laboratories in low-resource countries may differ from region to region and country to country. To better understand current gaps and inform our engagement with partners in Africa, a needs assessment survey was distributed to 1427 ADLM members in Africa and further disseminated through local partners, resulting in 121 responses from participants across 8 countries in the region. Additionally, interviews were conducted with laboratory professionals from the countries surveyed. The surveys primarily focused on quality management, continuing education, budgeting, infrastructure and funding, supplies, and staffing issues. The data collected from the surveys and interviews strongly indicate that respondents face major challenges in all areas assessed, including lack of funding, lack of equipment, lack of quality control (QC) and external quality assessment (EQA) materials, gaps in quality management, lack of appropriate budgeting, staffing issues, and lack of accessible training/continuing education. Consistent with the primary focus of ADLM;s Global Quality Initiative, improved access to continuing education was identified as the primary need by the participants (58%). The assessment highlights that while a strong role for educational workshops in mitigating some of the challenges continues to exist, there is also an opportunity to broaden the scope of the working groups beyond education.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1231-1242"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148309736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Commentary on A Diagnostic Pivot Triggered by a Cerebrospinal Fluid Critical Value.","authors":"Allison L Haas","doi":"10.1093/jalm/jfag073","DOIUrl":"10.1093/jalm/jfag073","url":null,"abstract":"","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1276-1277"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147989400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analytical Performance Evaluation of the Cardiac Troponin T High Sensitivity Gen 6 Assay.","authors":"Marko Knoll, Lori B Daniels, Christian Mueller, Nicholas L Mills, Evangelos Giannitsis, Alisa F A Rösser, Dunja Kurtoic, Annika Wahl, Richard Body, Robert H Christenson, Christa Cobbaert, Christopher R deFilippi, Kai M Eggers, Kenji Inoue, Allan S Jaffe, Cian P McCarthy, James McCord, Johannes T Neumann, Torbjørn Omland, Cynthia Papendick, Yader Sandoval, Jack Wei Chieh Tan, Martin P Than, Raphael Twerenbold, W Frank Peacock, Steven J R Meex","doi":"10.1093/jalm/jfag031","DOIUrl":"10.1093/jalm/jfag031","url":null,"abstract":"<p><strong>Background: </strong>High-sensitivity cardiac troponin (hs-cTn) assays are recommended for the diagnosis of acute myocardial infarction. Here, we characterize the analytical performance of a next-generation hs-cTn assay, Elecsys® Troponin T hs Gen 6 (Roche Diagnostics International).</p><p><strong>Methods: </strong>Surplus lithium-heparin plasma or serum samples from patients or healthy volunteers were run on Cobas® e 801, e 402, and Pro analyzers. Limits of blank (LoB), limits of detection (LoD), and limits of quantitation (LoQ) were determined according to CLSI EP17-A2, with target values of 1.0 and 1.5 ng/L for LoB/LoD and 3.0 ng/L (10% CV) and 1.5 ng/L (20% CV) for LoQ, respectively. Precision was measured, per CLSI EP17-A2, using 3 QC samples (approximately 4, 30, and 220 ng/L), 12 native samples, and 3 reagent lots. Linearity, per CLSI EP06-Ed2, was determined by diluting samples with cardiac troponin T (cTnT) concentration above the measuring range with a low/blank sample. Interference (per Glick) with endogenous and assay components at 5 cTnT concentrations was assessed.</p><p><strong>Results: </strong>Measured values for LoB, LoD, and LoQ at 10% and 20% CV were 0.1 to 0.7 ng/L, 0.3 to 1.4 ng/L, 1.0 to 2.9 ng/L, and 0.4 to 1.2 ng/L, respectively. Repeatability CVs were 1.0 to 5.8% for mean cTnT concentrations of 2.6 to 9230 ng/L in lithium-heparin plasma. High precision was shown across lots, and linearity was observed across the measuring range (1.5 to 9500 ng/L, all Pearson's r = 1.00). No interferences were observed, specified up to ≤1000 mg/dL hemoglobin, ≤50 mg/dL [≤855 µmol/L] icterus/bilirubin, and ≤1200 ng/mL biotin.</p><p><strong>Conclusions: </strong>The analytical performance characterization of the assay demonstrated high sensitivity, high precision at the low end and across the measuring range, and resistance to interference.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1009-1025"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147515553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sample Size Guidance and Justification for Studies of Biological Variability.","authors":"Alice J Sitch, Jacqueline Dinnes, Sue Mallett, Jonathan J Deeks","doi":"10.1093/jalm/jfag062","DOIUrl":"10.1093/jalm/jfag062","url":null,"abstract":"<p><strong>Background: </strong>Good estimates of analytical, within-subject, and between-subject variation, from appropriately designed biological variability studies, allow the potential for a biomarker to diagnose and monitor disease to be assessed in addition to setting goals for test performance. Sample sizes for these studies require consideration of the numbers of participants (n1), observations per participant (n2), and replicates of each observation (n3). Little guidance exists to compute these values.</p><p><strong>Methods: </strong>Data was simulated to examine the effect of changes in each component of sample size on analytical, within-subject, and between-subject variability, and on common measures of variability including the coefficient of variation (CV), reference change values (RCV), and index of individuality (II).</p><p><strong>Results: </strong>Simulations showed the precision of estimated results (CVs, RCVs, and IIs) for varying sample sizes. Greater numbers of participants increased the precision of estimated analytical, within-subject, and between-subject variability; increasing the number of observations per participant increases the precision of estimates of analytical and within-subject variability; and increasing the number of replicates of observations per participants increases precision of only analytical variability.</p><p><strong>Conclusions: </strong>The sample sizes for biological variability studies can be planned better, with consideration of the primary estimate evaluated in a study and resource used to increase the precision of this estimate. Studies with sample sizes too small to achieve reasonable precision can be redeveloped or abandoned, minimizing research waste. If the desired precision of variability components is known, values for the sample size (number of participants, observations and replicates of observations) can be determined.</p>","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1184-1196"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148158236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainability through Evidence-Based Equations: A Pilot Study Modeling the Friedewald and NIH-Sampson Equations.","authors":"Stephanie A Hart, Joesph R Wiencek","doi":"10.1093/jalm/jfag082","DOIUrl":"10.1093/jalm/jfag082","url":null,"abstract":"","PeriodicalId":46361,"journal":{"name":"Journal of Applied Laboratory Medicine","volume":" ","pages":"1292-1294"},"PeriodicalIF":2.3,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148220200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}