Practical Laboratory Medicine最新文献

{"title":"Diagnostic value of full blood count derived systemic inflammatory biomarkers in malaria infection","authors":"Joseph Boachie ,&nbsp;Derrick Ahiable ,&nbsp;Leticia Awonbiistemi Ajabuin ,&nbsp;Richard Amissah ,&nbsp;Abigail Asmah-Brown ,&nbsp;Safianu Apalebilah ,&nbsp;Ama Gyasiwaah Owusu-Poku ,&nbsp;Henrietta Eshun ,&nbsp;Patrick Adu ,&nbsp;Joel Karikari Nyarkoh","doi":"10.1016/j.plabm.2025.e00494","DOIUrl":"10.1016/j.plabm.2025.e00494","url":null,"abstract":"<div><h3>Background</h3><div>Malaria remains a public health issue. Its associated inflammatory responses can easily shift from benefit to detriment, making early detection of malarial inflammation crucial. The full blood count promises to be a less expensive assay serving as a surrogate marker for inflammation. This study, therefore, aimed to determine the diagnostic value of FBC-derived systemic inflammatory biomarkers in malaria infection.</div></div><div><h3>Method</h3><div>We employ a single point case-control design that included 45 malaria patients and 50 healthy individuals. We collected their anthropometric, sociodemographic, and clinical information. FBC estimation and malaria parasite enumeration were determined for each participant.</div></div><div><h3>Results</h3><div>Malaria patients had higher values of all the systemic inflammatory biomarkers (monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and aggregate index of systemic inflammation (AISI)) compared with healthy individuals. There was significant moderate correlation between parasite count and NLR, and MLR (ρ = 0.5 and ρ = 0.4) and a weak negative correlation with PLR and AISI (ρ = - 0.2 each). A receiver operator characteristic (ROC) curve analysis showed that NLR (AUC = 0.937) had an excellent diagnostic and predictive value, with sensitivity of 86.7 % and specificity of 92.0 %.</div></div><div><h3>Conclusion</h3><div>We have shown that the FBC-derived inflammatory biomarker— NLR— increases as parasite count increases. At a level of 2.12 and above, NLR is 86.7 % sensitive and 92.0 % specific in identifying the inflammatory state in malaria patients. Our findings show that the FBC-derived systemic inflammatory biomarkers provide a solution to the need for cost-effective surrogate inflammatory markers, especially in resource-deprived areas.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00494"},"PeriodicalIF":1.7,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144711388","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":"Rapid identification of daratumumab interference with M-protein detection using MALDI-TOF mass spectrometry: a case study involving renal light chain amyloidosis","authors":"Hou-Long Luo ,&nbsp;Anping Xu ,&nbsp;Ling Ji","doi":"10.1016/j.plabm.2025.e00493","DOIUrl":"10.1016/j.plabm.2025.e00493","url":null,"abstract":"<div><div>Therapeutic monoclonal antibodies (t-mAbs), such as daratumumab (anti-CD38), are increasingly used in plasma cell disorders including systemic AL amyloidosis. However, their exogenous IgG kappa/lambda components can mimic endogenous monoclonal immunoglobulins in serum immunofixation electrophoresis (IFE), leading to diagnostic challenges. We report a 48-year-old male with biopsy-confirmed lambda-restricted renal AL amyloidosis. After transitioning to daratumumab-CyBorD therapy following CyBorD failure, his serum IFE unexpectedly revealed biclonal bands—a cathodal IgG kappa and anodal IgG lambda—suggesting biclonal gammopathy. Suspecting daratumumab interference (an IgG kappa antibody), we employed mass spectrometry (iMS-LC assay) for definitive analysis. Post-treatment serum showed two distinct peaks (endogenous lambda: <em>m</em>/<em>z</em> 22,718; daratumumab kappa: <em>m</em>/<em>z</em> 23,389), while pre-treatment serum contained only the endogenous lambda peak (<em>m</em>/<em>z</em> 22,716). This confirms daratumumab generates a cathodal IgG kappa band mimicking pathological gammopathy. To prevent diagnostic errors in plasma cell disorder monitoring, laboratories should proactively identify t-mAb interference using historical controls and targeted mass spectrometry.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00493"},"PeriodicalIF":1.7,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633080","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":"Evaluation of harmonization among thyroid hormone testing systems: A comparative study based on external quality assessment data","authors":"Lirui Kong ,&nbsp;Yanqun Liu ,&nbsp;Chaoqiong Zhou ,&nbsp;Dahai He ,&nbsp;Xiaoheng Wu ,&nbsp;Ying Huang ,&nbsp;Yehong Xie ,&nbsp;Xiaohua Xu ,&nbsp;Lin Wang ,&nbsp;Feng Wu ,&nbsp;Yan Zhang","doi":"10.1016/j.plabm.2025.e00491","DOIUrl":"10.1016/j.plabm.2025.e00491","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate thyroid hormone test harmonization using external quality assessment (EQA) data, guiding laboratory quality enhancement and big data interoperability.</div></div><div><h3>Methods</h3><div>EQA data for T3, T4, FT3, FT4, and TSH from January 2022 to December 2024 were collected. We calculated the total allowable error for both our laboratory (TEa-Lab) and peer groups (TEa-peer) using bias and coefficient of variation data. We derived harmonization indices (HI) by comparing TEa values against three biological variation thresholds (minimum, desirable, and optimal). An HI value ≤ 1 indicated satisfactory harmonization.</div></div><div><h3>Results</h3><div>The TSH test in our laboratory showed desirable harmonization; however, the HI for T3, T4, FT3, and FT4 ranged from 1.1 to 1.9, failing to reach the minimum harmonization level. Among the peer group tests, the level of coordination of each analysis system varies, and the harmonization levels ranging from below the minimum to the optimal harmonization level, even failing to reach the minimum level. The harmonization level of thyroid hormones between our laboratory and peer groups showed strong consistency.</div></div><div><h3>Conclusion</h3><div>The HI values quantitatively calculated from EQA data accurately reflect the harmonization level between thyroid hormone testing systems in the laboratory and peer groups. This helps identify laboratory issues and implement corrective actions, providing a reference for laboratory big data interoperability and clinical decision-making.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00491"},"PeriodicalIF":1.7,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633079","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":"Differential Distributions: A refined methodology to indirect reference interval estimation by including Patient's health status according to associated ICD-10 codes","authors":"David Schär ,&nbsp;Tobias U. Blatter ,&nbsp;Harald Witte ,&nbsp;Jivko Stoyanov ,&nbsp;Martin Hersberger ,&nbsp;Christos T. Nakas ,&nbsp;Alexander B. Leichtle","doi":"10.1016/j.plabm.2025.e00492","DOIUrl":"10.1016/j.plabm.2025.e00492","url":null,"abstract":"<div><h3>Background</h3><div>Traditional methods for estimating reference intervals (RIs) using patient's blood test results from the clinical routine, typically remove outliers without considering the nuanced health statuses of patients. This removes a vast majority of test results for reference interval estimation without considering the actual health status of the patient.</div></div><div><h3>Methods</h3><div>We introduce the Differential Distribution Method (DDM) which uses laboratory routine data coded with ICD-10 to approximate an underlying non-diseased age and sex stratified population from mixed clinical data. By removing test results that stem from subpopulations significantly different from the general population, reference intervals can be generated stratified by sex and age, taking into account the associated health conditions of the patients as derived by the ICD-10 coding system.</div></div><div><h3>Results</h3><div>Applying the DDM to blood plasma potassium levels demonstrated its ability to adjust RIs dynamically across different patient groups. The method effectively differentiated RIs in a decade-based stratification, showing significant variability and tighter confidence intervals, particularly in older (above 60 years old) adults. The RIs were slightly wider with advancing age in both males and females, while their standard deviation was reduced by removing large portions of test results differing significantly, grouped by either their individual ICD-10 code or clusters of ICD-10 codes.</div></div><div><h3>Conclusions</h3><div>This DDM data mining approach offers a robust framework for RI inference by generating adjusted RIs that incorporate clinical nuances reflected in ICD-10 codes. This approach not only enhances the accuracy of patient diagnostics but also facilitates the identification of potential multimorbidities affecting laboratory results.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00492"},"PeriodicalIF":1.7,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605542","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":"Exploring the impact of pre-analytical processes on the determination of neuron-specific enolase in serum samples","authors":"Tang Honghui ,&nbsp;Wang Yifei ,&nbsp;Bian Sihan ,&nbsp;Mao Yanqing ,&nbsp;Wang Lin","doi":"10.1016/j.plabm.2025.e00490","DOIUrl":"10.1016/j.plabm.2025.e00490","url":null,"abstract":"<div><h3>Objective</h3><div>To explore pre-analysis factors affecting the results of neuron-specific enolase (NSE) testing of serum samples, select optimal testing conditions, and reduce the false-positive rate of NSE.</div></div><div><h3>Methods</h3><div>Serum NSE levels were measured using the Roche e801 electrochemiluminescence immunoassay in healthy participants who underwent physical examinations at the Fourth Affiliated Hospital of Soochow University from September 2022 to December 2024, including both outpatients and hospitalized patients. Further, we analyzed the effects of various pre-analytical factors on the NSE positivity rate (NSE&gt;16.3 ng/mL was judged to be NSE-positive) and the proportion of hemolysis index (H) ≥13 (H = 13 was equivalent to hemoglobin concentration of 13 mg/dl).</div></div><div><h3>Results</h3><div>This study found that the positive rate of NSE and the H ≥ 13 proportion were influenced by factors such as hemolysis, the method of sample transportation, pre-centrifugation storage time, the brand of blood collection tube, and centrifugation conditions. However, post-centrifugation storage time had little effect on these results.</div></div><div><h3>Conclusion</h3><div>After blood collection, the NSE positive rate and the H ≥ 13 proportion significantly decreased using a gentler transportation method, such as a box logistics or manual transport, centrifuging within 30–40 min or no longer than 1 h at the latest post-collection, and centrifuging at 2100 <em>g</em> (acceleration 4, deceleration 6) and 20 °C for 10 min with brand B blood collection tubes. Under these conditions, there was no significant impact on NSE results for males with H &lt; 6 and females with H &lt; 5.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00490"},"PeriodicalIF":1.7,"publicationDate":"2025-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144581185","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":"External quality assessment of genetic testing for hereditary hearing loss in Shanghai and other regions","authors":"Yun Bao,&nbsp;Pengyin Zhang,&nbsp;Jing Quan,&nbsp;Xue Yang,&nbsp;Yanqun Xiao,&nbsp;Xiaobo Hu","doi":"10.1016/j.plabm.2025.e00488","DOIUrl":"10.1016/j.plabm.2025.e00488","url":null,"abstract":"<div><h3>Objectives</h3><div>Hereditary hearing loss is one of the most common birth defects in humans. Genetic screen in pregnant women and newborns could provide prenatal intervention or guidance on the early diagnosis and treatment. Currently, this screen has been widely applied; however, its accuracy and reliability have not been determined. The objective of this pioneering study was to evaluate the performance of clinical laboratories in Shanghai and other regions for their ability to analyze the genetic variants related with hearing loss.</div></div><div><h3>Methods</h3><div>The EQA program were carried out twice a year. We generated a sample panel consisting of five dry blood spots with genomic DNA from different cell lines with normal whole blood as the matrix. The panel included four samples with nine different pathogenic variants of <em>GJB2, GJB3, SLC26A4</em> as well as mitochondria DNA (mt DNA) and one wild type sample. The panel was distributed to participant laboratories for genetic analysis, and the results were compared and scored.</div></div><div><h3>Results</h3><div>Thirty and twenty-nine clinical laboratories participated in the two EQA scheme in 2023, respectively. 28 (93.33 %) and 27 (93.10 %) laboratories achieved an acceptable or superior performance score(≥80). There were ten errors with eight false-negative and two false-positive results in the first EQA scheme, and seven errors with five false-negative and two false-positive in the second EQA scheme.</div></div><div><h3>Conclusions</h3><div>The results indicate that the majority of the clinical genetic analysis of deafness-related genes were satisfactory in China, while some participant laboratories needed further improvement. In addition, external quality assessment was demonstrated as an important method for monitoring the performance of clinical laboratories.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00488"},"PeriodicalIF":1.7,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550042","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":"Performance validation of Abbott Alinity i chemiluminescence analyzer for five thyroid function tests","authors":"Hongyu Zhang ,&nbsp;Baixiu Wu ,&nbsp;Liuhua Ke ,&nbsp;Zheng Peng","doi":"10.1016/j.plabm.2025.e00487","DOIUrl":"10.1016/j.plabm.2025.e00487","url":null,"abstract":"<div><h3>Objective</h3><div>To verify and evaluate the performance of the Abbott Alinity i chemiluminescence analyzer for five thyroid function tests.</div></div><div><h3>Method</h3><div>Referring to the relevant documents of the Clinical and Laboratory Standards Institute (CLSI) and related literature, the precision, accuracy, linear range, reference interval, and sample carryover effect of Abbott Alinity i immunoassay system for measuring FT3, FT4, T3, T4, and TSH were verified and analyzed.</div></div><div><h3>Results</h3><div>Precision: Repeatability ranged from 1.23 % to 6.11 %, and intermediate precision ranged from 1.84 % to 7.33 %, both meeting the quality targets (≤6.25 % and ≤8.33 %, respectively). Accuracy: The deviation between the mean value and the target value was less than 12.5 %, indicating good agreement. Linearity: For T3, T4, and TSH, the 95 % confidence intervals of the deviation from linearity (difference between measured and expected value) were entirely within the allowable deviation limits (ADL). For FT3 and FT4, manufacturer guidelines preclude dilution; thus, linearity verification was omitted. Reference interval: All test values of 20 healthy individuals were within the reference intervals provided by the manufacturer. Sample carryover effect: The sample carryover effect ranged from −0.4 % to 0.17 %, which met the requirement of less than 1 %.</div></div><div><h3>Conclusion</h3><div>The Abbott Alinity i analyzer demonstrated acceptable performance in precision, accuracy, linearity (for T3, T4, and TSH), reference interval, and carry-over effect for the five thyroid function tests, meeting manufacturer specifications.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00487"},"PeriodicalIF":1.7,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517730","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":"Validation of an assay for NGAL in a pediatric population","authors":"Nazmin Bithi ,&nbsp;Ridwan B. Ibrahim ,&nbsp;Estella L. Tam ,&nbsp;Radwa Almamoun ,&nbsp;Annette C. Frenk Oquendo ,&nbsp;Ayse Akcan-Arikan ,&nbsp;Sridevi Devaraj","doi":"10.1016/j.plabm.2025.e00486","DOIUrl":"10.1016/j.plabm.2025.e00486","url":null,"abstract":"<div><h3>Background and objectives</h3><div>Acute kidney injury (AKI) poses a serious clinical challenge, particularly in high-risk environments, due to its association with increased morbidity and mortality. Traditional diagnostic markers, such as serum creatinine, often detect AKI only after significant kidney damage has occurred, limiting opportunities for early intervention. Neutrophil gelatinase-associated lipocalin (NGAL) has emerged as a promising early biomarker due to its rapid upregulation following kidney ischemia. NGAL supports renal recovery by reducing toxicity and promoting tubular regeneration via heme oxygenase-1 activity. This study aimed to validate the BioPorto ProNephro AKI™ turbidimetric immunoassay for urinary NGAL on the Ortho Vitros XT7600 analyzer and evaluate its clinical utility in detecting early-stage AKI.</div></div><div><h3>Design and methods</h3><div>Assay performance was evaluated in accordance with CLSI guidelines, assessing precision, linearity, method agreement, specificity, and reference range. Method comparison involved 20 urine samples, while reference range verification used 57 pediatric samples. A clinical validation study included 21 pediatric CRRT patient samples to assess real-world diagnostic performance.</div></div><div><h3>Results</h3><div>The assay demonstrated strong precision (intra-assay CV: 1.3–1.8 %; inter-assay CV: 1.8–2.7 %) and excellent linearity (18–1140 ng/mL; extended to 15,000 ng/mL with dilution). High correlation (r = 0.9836) was observed in method comparison. Specificity tests showed minimal interference. Clinical validation yielded 76.19 % sensitivity and 100 % specificity for AKI detection.</div></div><div><h3>Conclusions</h3><div>The BioPorto ProNephro AKI™ assay on the Ortho Vitros XT7600 shows high sensitivity and specificity for urinary NGAL detection in pediatric patients, enabling early AKI identification, timely intervention, and potentially improved clinical outcomes through enhanced diagnostic performance.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00486"},"PeriodicalIF":1.7,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491144","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":"External quality assessment for nucleic acid quantitative testing of human hepatitis B and hepatitis C virus in Chongqing, China: 2009–2024","authors":"Yuanyuan Guo ,&nbsp;Kun Wang ,&nbsp;Liying Wang,&nbsp;Shuang Liu,&nbsp;Zhijie Li,&nbsp;Tian Li,&nbsp;Changchun Niu","doi":"10.1016/j.plabm.2025.e00485","DOIUrl":"10.1016/j.plabm.2025.e00485","url":null,"abstract":"<div><h3>Background</h3><div>To achieve the goal of eliminating viral hepatitis as a public health threat by 2030, accurate detection of HBV-DNA and HCV-RNA is crucial. This study presents the implementation of HBV-DNA and HCV-RNA External Quality Assessment (EQA) programs conducted in Chongqing, China, from 2009 to 2024, highlighting the significant contributions made by clinical laboratories.</div></div><div><h3>Methods</h3><div>Over a span of 16 years, a total of 160 samples were distributed in the HBV-DNA EQA program, while the HCV-RNA EQA program disseminated 105 samples encompassing diverse concentration levels. Factors such as the number of participating laboratories, employed detection methodologies, utilized reagents, and test outcomes were evaluated to assess the HBV-DNA and HCV-RNA detection capabilities of clinical laboratories over the past decade.</div></div><div><h3>Results</h3><div>By 2024, the number of laboratories participating in HBV-DNA EQA activities had increased from 45 in 2009 to 110 in 2024, representing a 144.44 % increase. Similarly, the number of laboratories participating in HCV-RNA EQA activities had risen from 7 in 2014 to 30 in 2024, marking a 328.57 % increase. The accuracy rate for HBV-DNA EQA activity results improved from 85.37 % in 2009 to 98.18 % in 2024, while the accuracy rate for HCV-RNA EQA activity results rose from 66.67 % in 2014 to 96.67 % in 2024. Satisfactory reproducibility was observed in parallel samples. However, certain laboratories exhibited significant bias in low- and high-concentration samples.</div></div><div><h3>Conclusion</h3><div>The performance of laboratories in Chongqing, China, for HBV-DNA and HCV-RNA testing has consistently improved through their participation in EQA programs. In the future, sample distribution should include more challenging ones, particularly low- or high-concentration samples. Emphasis should also be placed on standardized operation and performance validation of the assay system.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00485"},"PeriodicalIF":1.7,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514013","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":"Comparative evaluation of four new immunoassays and LC-MS/MS for the measurement of urinary free cortisol in Cushing's syndrome diagnosis","authors":"Qi Zhang ,&nbsp;Danni Mu ,&nbsp;Yichen Ma ,&nbsp;Yuemeng Li ,&nbsp;Yumeng Gao ,&nbsp;Yingying Hu ,&nbsp;Kui Zhang ,&nbsp;Fang Zhao ,&nbsp;Ran Gao ,&nbsp;Liangyu Xia ,&nbsp;Huijuan Zhu ,&nbsp;Songlin Yu ,&nbsp;Ling Qiu ,&nbsp;Xinqi Cheng","doi":"10.1016/j.plabm.2025.e00484","DOIUrl":"10.1016/j.plabm.2025.e00484","url":null,"abstract":"<div><h3>Objectives</h3><div>Twenty-four-hour urinary free cortisol (UFC) measurement is the initial diagnostic test for Cushing's syndrome (CS). We compared UFC determination by four new immunoassays using Autobio A6200, Mindray CL-1200i, Snibe MAGLUMI X8 and Roche 8000 e801 with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Additionally, we evaluated the value of 24-h UFC measured by four direct immunoassays for diagnosing CS.</div></div><div><h3>Methods</h3><div>Residual 24-hr urine samples of 94 CS and 243 non-CS patients collected from previous cohort were used. A laboratory-developed LC-MS/MS method was used as reference. UFC was measured by immunoassays using Autobio, Mindray, Snibe and Roche platforms. Method was compared using Passing–Bablok regression and Bland–Altman plot analyses. Cut-off values for each assay and corresponding sensitivities and specificities were calculated by ROC analysis.</div></div><div><h3>Results</h3><div>All four immunoassays showed strong correlations with LC-MS/MS (Spearman coefficient r = 0.950, 0.998, 0.967, and 0.951, respectively). All immunoassays showed proportionally positive bias. The areas under the curve were 0.953 for Autobio, 0.969 for Mindray, 0.963 for Snibe, and 0.958 for Roche. The cut-off values varied from 178.5 to 272.0 nmol/24 h). Assay sensitivity and specificity ranged from 89.66 % to 93.10 % and from 93.33 % to 96.67 %, respectively.</div></div><div><h3>Conclusions</h3><div>Four newly available direct immunoassays for measuring UFC show good analytical consistency compared to LC-MS/MS. The elimination of organic solvent extraction simplifies workflows while maintaining high diagnostic accuracy. Additionally, they exhibited similarly high diagnostic accuracy for CS identification. Future multi-center studies are needed to validate our findings and establish method-specific UFC cut-off values to enhance clinical utility.</div></div>","PeriodicalId":20421,"journal":{"name":"Practical Laboratory Medicine","volume":"46 ","pages":"Article e00484"},"PeriodicalIF":1.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144272332","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}