Clinical chemistry and laboratory medicine最新文献

{"title":"Biological variation of serum cholinesterase activity in healthy subjects.","authors":"Emiş Deniz Akbulut, Müjgan Ercan","doi":"10.1515/cclm-2025-0240","DOIUrl":"https://doi.org/10.1515/cclm-2025-0240","url":null,"abstract":"<p><strong>Objectives: </strong>Serum cholinesterase (ChE) 3.1.1.8 is measured to assess exposure to organophosphorus pesticides and determine deficiency related to prolonged apnea after the induction of anesthesia with certain drugs and less often as an indicator of liver function. Biological variation (BV) is an accepted endogenous source that contributes to the total variation in laboratory medicine. No data on the BV of serum ChE have been found in the European Federation of Clinical Chemistry and Laboratory Medicine BV database. Thus, this study aimed to contribute to the data on BV of serum ChE activity.</p><p><strong>Methods: </strong>Detailed inclusion and exclusion criteria were used for the enrollment of 20 (10 women and 10 men, 8-10 weeks) ostensibly healthy volunteers from Turkey. The serum ChE activity was measured on Roche Cobas c501. Statistical analyses included the detection of outliers, control for the normality of distribution, checking steady-state condition, assessment for homogeneity, subgroup analysis, analysis of variance with 95 % confidence intervals, and estimation of analytical performance specifications (APS).</p><p><strong>Results: </strong>After exclusion, 332 results were included in the study. The within-subject BV of men (3.5 % [2.9-4.2 %]) was lower than that of women (4.8 % [4.1-5.8 %]). Between-subject BV of men and women were 15.9 % [10.5-32.4 %] and 12.3 % [8.4-22.6 %], respectively. The index of individuality was 0.18 and reference change value (RCV) was +9.1 %/-8.3 %. The calculated desirable APS for imprecision and bias were 1.7 and 3.2 %, respectively.</p><p><strong>Conclusions: </strong>We believe that this study will contribute to the BV data on serum ChE activity. The prominent individuality of serum ChE activity favors the use of RCV instead of population-based reference intervals for more reliable follow-up.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143990044","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":"Development of commutable candidate certified reference materials from protein solutions: concept and application to human insulin.","authors":"Shiwen Luo, Yao Tan, Ziliang Wang, Bin Yang, Yahui Liu, Jing Wang, Liqing Wu","doi":"10.1515/cclm-2025-0329","DOIUrl":"https://doi.org/10.1515/cclm-2025-0329","url":null,"abstract":"<p><strong>Objectives: </strong>To explore the reasons behind the lack of commutability in protein solution reference materials (RMs) and seeks to eliminate these factors in order to develop commutable reference materials, using human insulin (hINS) as example, to meet the growing demand for standardization in <i>in vitro</i> diagnostics.</p><p><strong>Methods: </strong>A concept for development of commutable protein solution RMs by matrix matching, structural-activity analysis, higher order structure adjustment, active concentration measurement, and commutability verification was investigated. This concept was applied in the development of hINS solution candidate certified RMs (cCRMs). Bovine serum solution (7 %) was used for matrix matching and hINS-Zn²⁺ aggregates were found to be the key for commutability. hINS-Zn²⁺ aggregates were constructed <i>in vitro</i> and the presence of the aggregates was confirmed through circular dichroism spectroscopy and mass photometry. The active concentration of the aggregate solution was analyzed using surface plasmon resonance. Then, six levels of hINS solution cCRMs were developed and the commutability was evaluated using both CLSI EP14 and IFCC approaches.</p><p><strong>Results: </strong>The hINS solution cCRMs exhibited excellent homogeneity and remained stable for at least 6 months when stored at -70 °C. The relative uncertainties of these cCRMs ranged from 4.0 to 5.0 %. Both CLSI EP14 and IFCC commutability evaluations indicated good commutability between routine chemiluminescent immunoassay systems.</p><p><strong>Conclusions: </strong>A new concept for developing commutable RMs with pure protein material, which avoids the challenges in developing commutable matrix RMs and should contribute to the standardization of clinical test results for proteins, was successfully applied to develop commutable hINS solution cCRMs.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143977580","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":"New insights in preanalytical quality.","authors":"Mario Plebani, Sheri Scott, Ana-Maria Simundic, Mike Cornes, Andrea Padoan, Janne Cadamuro, Pieter Vermeersch, Hikmet Can Çubukçu, Álvaro González, Mads Nybo, Gian Luca Salvagno, Seán J Costelloe, Rosanna Falbo, Alexander von Meyer, Enrico Iaccino, Francesco Botrè, Giuseppe Banfi, Giuseppe Lippi","doi":"10.1515/cclm-2025-0478","DOIUrl":"https://doi.org/10.1515/cclm-2025-0478","url":null,"abstract":"<p><p>The negative impact of preanalytical errors on the quality of laboratory testing is now universally recognized. Nonetheless, recent technological advancements and organizational transformations in healthcare - catalyzed by the still ongoing coronavirus disease 2019 (COVID-19 pandemic) - have introduced new challenges and promising opportunities for improvement. The integration of value-based scoring systems for clinical laboratories and growing evidence linking preanalytical errors to patient outcomes and healthcare costs underscore the critical importance of this phase. Emerging topics in the preanalytical phase include the pursuit of a \"greener\" and more sustainable environment, innovations in self-sampling and automated blood collection, and strategies to minimize patient blood loss. Additionally, efforts to reduce costs and enhance sustainability through patient blood management have gained momentum. Digitalization and artificial intelligence (AI) offer transformative potential, with applications in sample labeling, recording collection events, and monitoring sample conditions during transportation. AI-driven tools can also streamline the preanalytical workflow and mitigate errors. Specific challenges include managing hemolysis and developing strategies to minimize its impact, addressing issues related to urine collection, and designing robust protocols for sample stability studies. The rise of decentralized laboratory testing presents unique preanalytical hurdles, while emerging areas such as liquid biopsy and anti-doping testing introduce novel complexities. Altogether, these advancements and challenges highlight the dynamic evolution of the preanalytical phase and the critical need for continuous innovation and standardization. This collective opinion paper, which summarizes the abstracts of lectures delivered at the two-day European Federation of Laboratory Medicine (EFLM) Preanalytical Conference entitled \"New Insight in Preanalytical Quality\" (Padova, Italy; December 12-13, 2025), provides a comprehensive overview of preanalytical errors, offers some important insights into less obvious sources of preanalytical vulnerability and proposes efficient opportunities of improvement.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143986847","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":"The accuracy of presepsin in diagnosing neonatal late-onset sepsis in critically ill neonates: a prospective study.","authors":"Cinzia Auriti, Domenico Umberto De Rose, Chiara Maddaloni, Lucilla Ravà, Ludovica Martini, Eleonora Di Tommaso, Paola Bernaschi, Emanuel Paionni, Ottavia Porzio, Fiammetta Piersigilli, Marco Iannetta, Andrea Dotta, Maria Paola Ronchetti","doi":"10.1515/cclm-2025-0128","DOIUrl":"https://doi.org/10.1515/cclm-2025-0128","url":null,"abstract":"<p><strong>Objectives: </strong>The diagnostic accuracy of presepsin (P-SEP) in the newborn is still under evaluation.</p><p><strong>Methods: </strong>In a multicenter study, we studied the accuracy of P-SEP as a diagnostic marker of late-onset sepsis (LOS) in critical newborns with underlying disorders, to define the most accurate cut-off to distinguish infected from uninfected patients.</p><p><strong>Results: </strong>Sixty-nine/351 newborns without infections at admission developed LOS. The median P-SEP value at T0 (admission) was 518.0 ng/L (IQR 313.0-789.0), without significant differences related to underlying diseases (p=0.52). In neonates who developed LOS, P-SEP increased at the onset of infection (T1) (median: 816.0 ng/L) and after 24-48 h (median: 901.0 ng/L) compared with their value at admission (median: 560.0 ng/L) (p<0.01 and p=0.03, respectively). The area under the ROC curve at T1 was 0.71 (95 % CI 0.65-0.78) when all cases of sepsis were included in the analysis and increased to 0.74 (95 % CI 0.66-0.81) considering only confirmed sepsis. Approximately two-thirds of patients were correctly classified, setting the cut-off at 713 ng/L, with a negative predictive value of 89.0 %.</p><p><strong>Conclusions: </strong>At a cut-off of 713 ng/L, P-SEP has good accuracy in diagnosing LOS in critically ill newborns. In uninfected newborns, the median value of P-SEP is not influenced by any underlying pathology.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143962217","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":"Evaluation of error detection and treatment recommendations in nucleic acid test reports using ChatGPT models.","authors":"Wenzheng Han, Chao Wan, Rui Shan, Xudong Xu, Guang Chen, Wenjie Zhou, Yuxuan Yang, Gang Feng, Xiaoning Li, Jianghua Yang, Kai Jin, Qing Chen","doi":"10.1515/cclm-2025-0089","DOIUrl":"https://doi.org/10.1515/cclm-2025-0089","url":null,"abstract":"<p><strong>Objectives: </strong>Accurate medical laboratory reports are essential for delivering high-quality healthcare. Recently, advanced artificial intelligence models, such as those in the ChatGPT series, have shown considerable promise in this domain. This study assessed the performance of specific GPT models-namely, 4o, o1, and o1 mini-in identifying errors within medical laboratory reports and in providing treatment recommendations.</p><p><strong>Methods: </strong>In this retrospective study, 86 medical laboratory reports of Nucleic acid test report for the seven upper respiratory tract pathogens were compiled. There were 285 errors from four common error categories intentionally and randomly introduced into reports and generated 86 incorrected reports. GPT models were tasked with detecting these errors, using three senior medical laboratory scientists (SMLS) and three medical laboratory interns (MLI) as control groups. Additionally, GPT models were tasked with generating accurate and reliable treatment recommendations following positive test outcomes based on 86 corrected reports. χ2 tests, Kruskal-Wallis tests, and Wilcoxon tests were used for statistical analysis where appropriate.</p><p><strong>Results: </strong>In comparison with SMLS or MLI, GPT models accurately detected three error types, and the average detection rates of the three GPT models were 88.9 %(omission), 91.6 % (time sequence), and 91.7 % (the same individual acted both as the inspector and the reviewer). However, the average detection rate for errors in the result input format by the three GPT models was only 51.9 %, indicating a relatively poor performance in this aspect. GPT models exhibited substantial to almost perfect agreement with SMLS in detecting total errors (kappa [min, max]: 0.778, 0.837). However, the agreement between GPT models and MLI was moderately lower (kappa [min, max]: 0.632, 0.696). When it comes to reading all 86 reports, GPT models showed obviously reduced reading time compared with SMLS or MLI (all p<0.001). Notably, our study also found the GPT-o1 mini model had better consistency of error identification than the GPT-o1 model, which was better than that of the GPT-4o model. The pairwise comparisons of the same GPT model's outputs across three repeated runs showed almost perfect agreement (kappa [min, max]: 0.912, 0.996). GPT-o1 mini showed obviously reduced reading time compared with GPT-4o or GPT-o1(all p<0.001). Additionally, GPT-o1 significantly outperformed GPT-4o or o1 mini in providing accurate and reliable treatment recommendations (all p<0.0001).</p><p><strong>Conclusions: </strong>The detection capability of some of medical laboratory report errors and the accuracy and reliability of treatment recommendations of GPT models was competent, especially, potentially reducing work hours and enhancing clinical decision-making.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143987649","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":"Impact of renal function impairment on kappa free light chain index.","authors":"Martin Schmidauer, Fabian Föttinger, Klaus Berek, Michael Auer, Robert Barket, Franziska Di Pauli, Nik Krajnc, Markus Ponleitner, Anne Zinganell, Tobias Zrzavy, Florian Deisenhammer, Janette Walde, Gabriel Bsteh, Harald Hegen","doi":"10.1515/cclm-2025-0007","DOIUrl":"https://doi.org/10.1515/cclm-2025-0007","url":null,"abstract":"<p><strong>Objectives: </strong>To investigate whether renal function impacts CSF κ-FLC concentration and/or κ-FLC index.</p><p><strong>Methods: </strong>Patients with non-inflammatory neurological diseases were eligible. κ-FLC index was calculated as (CSF κ-FLC/serum κ-FLC)/albumin quotient. Structural equation modeling (SEM) was used to evaluate the direct influence of GFR on serum κ-FLC concentration and albumin quotient (Q_alb), and via these two variables the indirect influence on CSF κ-FLC concentration.</p><p><strong>Results: </strong>A total of 129 patients with a median age of 65 years and 42 % females were included. κ-FLC index ranged from 0.57 to 3.56 and glomerular filtration rate (GFR) ranged from 17 to 128 mL/min/1.73 m². While a correlation of GFR with CSF κ-FLC concentration was observed (r= -0.52, p<0.001), there was no statistically significant correlation with κ-FLC index (r=0.14, p=0.113). SEM revealed that higher age was associated with lower GFR (β= -0.53), which led to higher serum κ-FLC concentration (β= -0.45) and higher Q_alb (β= -0.17), while CSF κ-FLC concentration increased with serum κ-FLC concentration (β=0.75) and Q_alb (β=0.39), indicating that GFR did not directly influence CSF κ-FLC concentration (RMSEA=0.043).</p><p><strong>Conclusions: </strong>CSF κ-FLC concentration is not directly affected by renal function. The κ-FLC index compensates for renal function effects by factoring in serum κ-FLC concentration and Q_alb. κ-FLC index can be interpreted without considering renal function.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143981305","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":"Direct screening and quantification of monoclonal immunoglobulins in serum using MALDI-TOF mass spectrometry without antibody enrichment.","authors":"Hou-Long Luo, Peng Ye, Yuxi Wang, Huan Ding, Beiqi Cao, Shangying Wu, Hui Yu, Rong He, Liansheng Wang, Yueying Huang, Anping Xu, Ling Ji","doi":"10.1515/cclm-2025-0203","DOIUrl":"https://doi.org/10.1515/cclm-2025-0203","url":null,"abstract":"<p><strong>Objectives: </strong>Monoclonal gammopathies (MGs) are characterized by the presence of monoclonal immunoglobulins (M-proteins). Currently, recommendations for screening of MGs primarily rely on nephelometry, turbidimetry and electrophoresis, which have inherent limitations in sensitivity and throughput. This study aimed to evaluate a novel MALDI-TOF MS-based method, the intact M-protein Screening-Light Chain Assay (iMS-LC Assay), for direct M-protein detection and quantification without antibody enrichment.</p><p><strong>Methods: </strong>Residual serum samples previously analyzed via serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) were reduced to dissociate light chains from heavy chains. MALDI-TOF MS was then performed to determine the presence of M-protein characteristic pattern. The iMS-LC Assay's analytical sensitivity, specificity, and screening efficacy in healthy populations were assessed.</p><p><strong>Results: </strong>The iMS-LC Assay successfully detected all M-proteins identified by SPE and demonstrated higher sensitivity in analytical and diagnostic studies. It accurately quantified M-proteins at concentrations below 10 g/L, with a detection limit of 0.2 g/L and the ability to detect levels below 0.1 g/L. For samples with M-protein concentrations >1 g/L, intra-assay and inter-assay coefficients of variation were <10 %. In prospective screening of M-proteins in the healthy population, the iMS-LC Assay detected M-proteins at a prevalence of 3.15 %, higher than IFE (1.87 %) and SPE (0.94 %).</p><p><strong>Conclusions: </strong>The iMS-LC Assay shows potential to replace SPE and drive advancements in the screening, diagnosis, and monitoring of MGs. Further validation of its clinical sensitivity and specificity is essential to determine its adequacy as a routine screening tool for M-proteins.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143980331","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":"An isotope dilution-liquid chromatography-tandem mass spectrometry-based candidate reference measurement procedure for the quantification of cortisone in human serum and plasma.","authors":"Myriam Ott, Neeraj Singh, Marie Kubicova, Friederike Bauland, Daniel Köppl, Alexander Gaudl, Andrea Geistanger, Uta Ceglarek, Manfred Rauh, Christian Geletneky, Judith Taibon","doi":"10.1515/cclm-2024-1478","DOIUrl":"https://doi.org/10.1515/cclm-2024-1478","url":null,"abstract":"<p><strong>Objectives: </strong>Cortisone is an inert precursor/metabolite of the potent steroid hormone cortisol. Measurement of serum cortisone levels and the cortisol-cortisone ratio can be useful for the diagnosis of dysfunction in the regulation of cortisol levels (i.e., severe and subtle apparent mineralocorticoid excess, low-renin primary aldosteronism). Therefore, an isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC MS/MS)-based candidate reference measurement procedure (RMP) to quantify cortisone in human serum/plasma was developed and validated.</p><p><strong>Methods: </strong>Quantitative nuclear magnetic resonance (qNMR) was utilized to assign absolute content (g/g) and SI-traceability to reference materials used as primary calibrators. A supported liquid extraction sample preparation protocol as well as a two-dimensional heart-cut LC approach for LC-MS/MS analysis were employed to mitigate matrix effects and prevent co-elution of interferences. Selectivity was determined by analyzing a matrix sample containing the analyte, the internal standard and six potential interferents. A post-column infusion experiment and a comparison of standard line slopes were performed to evaluate matrix effects. An extensive protocol over five days was applied to determine precision, accuracy and trueness. Measurement uncertainty (MU) was evaluated in compliance with current guidelines.</p><p><strong>Results: </strong>This RMP is suitable for analyzing cortisone within the 0.0800-120 ng/mL (0.222-333 nmol/L) range, demonstrating selectivity, sensitivity and matrix independence. Intermediate precision was ≤3.4 %, repeatability was ≤2.9 % across all concentration levels and relative mean bias ranged from -3.7 to 2.8 % across all tested matrices and concentrations. Expanded MU (k=2) for target value assignment (n=6) ranged from 2.1 to 5.5 %, irrespective of concentration or sample type.</p><p><strong>Conclusions: </strong>This RMP allows for accurate and reproducible determination of cortisone in human serum and plasma. Implementation of this method supports routine assay standardization and patient sample measurement with confirmed traceability.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143968284","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":"Assessment of serum free light chain measurements in a large Chinese chronic kidney disease cohort: a multicenter real-world study.","authors":"Xia Luo, Xiaomeng Zhang, Xu Yuan, Pan Zhao, Wenqian Zhang, Lingyan Deng, Liming Cheng","doi":"10.1515/cclm-2024-1226","DOIUrl":"https://doi.org/10.1515/cclm-2024-1226","url":null,"abstract":"<p><strong>Objectives: </strong>Diagnosing monoclonal gammopathy in chronic kidney disease (CKD) patients is challenging due to the complex interpretation of serum free light chain (FLC) levels. This study aimed to assess the FLC levels in a large cohort of Chinese CKD patients.</p><p><strong>Methods: </strong>We enrolled 5,287 patients with all-cause nondialysis CKD from three medical centers between February 2018 and April 2023. Central 95 % reference ranges were established using data from one center and validated in an independent subpopulation from the other two centers. The crude prevalence of light chain monoclonal gammopathy of undetermined significance (LC-MGUS) was assessed against established norms for the entire cohort and subgroups based on estimated glomerular filtration rate (eGFR).</p><p><strong>Results: </strong>A notable proportion of patients exceeded the standard reference limits for kappa (89.0 %), lambda (72.1 %), and FLC ratio (10.5 %), whereas non-eGFR-based renal reference interval identified only 0.3 % with abnormal FLC ratios. The iStopMM reference ranges showed higher out-of-range rates for absolute FLC levels in patients with preserved kidney function and lower rates in those with impaired kidney function, while the FLC ratio references remained robust across all groups. The crude prevalence of LC-MGUS was 10.4 % using standard ranges, predominantly kappa LC-MGUS (99.8 %). This prevalence decreased to 0.3 % with non-eGFR-based renal reference interval and 0.5 % with the iStopMM ranges. Using the newly established reference ranges, the crude prevalence was found to be 0.9 %.</p><p><strong>Conclusions: </strong>Our findings suggest that current FLC reference ranges are inadequate for the Chinese population, underscoring the need for eGFR-based reference ranges tailored to this demographic.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143976879","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":"Defining dried blood spot diameter: implications for measurement and specimen rejection rates.","authors":"Nick Flynn, Stuart J Moat","doi":"10.1515/cclm-2025-0183","DOIUrl":"https://doi.org/10.1515/cclm-2025-0183","url":null,"abstract":"<p><strong>Objectives: </strong>Dried blood spot (DBS) specimen acceptance guidelines recommend rejecting specimens based on DBS size, often expressed as a diameter. Computer vision methods can estimate DBS size from images obtained from standalone equipment, smartphone cameras or existing laboratory instrumentation. However, no consensus definition of DBS diameter exists. We assessed how different DBS diameter definitions affect measurement and specimen rejection rates.</p><p><strong>Methods: </strong>We compared computer vision estimates of DBS diameter on 1,991 DBS using two different calculation methods and on 22 DBS where paired images were taken from either side of the filter paper. We modelled the impact on specimen rejection rate in >163,000 DBS specimens.</p><p><strong>Results: </strong>Two different calculation methods for DBS diameter showed a mean difference <0.1 mm for circular DBS. Greater variability was observed for incorrectly applied DBS with a mean (standard deviation) difference of 0.29 (0.41) mm. DBS diameter measured from the front of the filter paper was approximately 0.41 (0.25) mm larger than from the back of the filter paper. Changing the DBS diameter definition could more than double the number of insufficient DBS (<8 mm), potentially leading to 4,000 additional repeat collections annually in the UK newborn screening programme.</p><p><strong>Conclusions: </strong>DBS diameter definition can have a small but important and easily avoidable impact on measurement, impacting specimen rejection rates. We recommend that DBS diameter is defined as the diameter of a circle with equal area to the DBS, when measured from the opposite side of the filter paper to blood application.</p>","PeriodicalId":10390,"journal":{"name":"Clinical chemistry and laboratory medicine","volume":" ","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143976098","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}