Within- and Between-Subject biological variation estimates of serum free light immunoglobulin chains in healthy individuals in Turkey

IF 2.9 3区医学 Q2 MEDICAL LABORATORY TECHNOLOGY

Clinica Chimica Acta Pub Date : 2025-08-08 DOI:10.1016/j.cca.2025.120545

Müjgan Ercan , Esra Fırat Oğuz , Mehmet Özcan , Hamit Hakan Alp

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引用次数: 0

Abstract

Serum light immunoglobulin chains (LCs) are critical biomarkers for the diagnosis, prognosis, and treatment response monitoring in monoclonal plasma cell dyscrasias. Robust performance standards based on biological variation (BV) data are essential for optimizing patient care. This study aimed to provide updated BV estimates for serum free LCs (κ and λ) as well as their κ/λ LC ratio. Serum samples from 25 healthy volunteers (10 men, 15 women) were collected weekly over approximately 9 weeks. Serum free LCs were measured in duplicate using the Roche Cobas c501 analyzer. BV estimates with 95 % confidence intervals were calculated using coefficient of variation (CV) in ANOVA for the entire group and by sex, following assessments for outliers, normality, steady-state conditions, and variance homogeneity. The within-subject BV (CV_I) estimates were 9.2 %, 8.6 %, 6.6 % for free κ, free λ, free κ/λ ratio, respectively. The between-subject BV (CV_G) estimates were 24.6 %, 26.6 %, and 17.5 %for free κ, free λ and free κ/λ ratio, respectively. No significant sex differences were observed for CV_I with the exception of free κ and free κ/λ ratio or CV_G in serum free LCs and their ratio. Free LCs and their κ/λ ratio exhibited marked individuality. Analytical performance specifications (APSs) for desirable imprecision and bias ranged 3.9 %–5.4 %, 4.3 %–5.8 % and 2.9 %–4.6 % for free κ, free λ and free κ/ λ ratio, respectively. This study provides updated, well-characterized BV estimates for serum free (κ and λ) and free κ/λ ratio, providing essential data to define APSs. The individuality of κ and λ underscores the importance of prioritizing reference change values over traditional reference intervals for improved diagnosis and monitoring in clinical practice.

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土耳其健康个体血清游离轻免疫球蛋白链的受试者内和受试者间生物学变异估计

血清轻免疫球蛋白链（LCs）是单克隆浆细胞病变诊断、预后和治疗反应监测的重要生物标志物。基于生物变异（BV）数据的稳健性能标准对于优化患者护理至关重要。本研究旨在为血清游离LC （κ和λ）及其κ/λ LC比值提供最新的BV估计。在大约9周的时间里，每周收集25名健康志愿者（10名男性，15名女性）的血清样本。使用罗氏Cobas c501分析仪一式两份测定血清游离lc。在对异常值、正态性、稳态条件和方差齐性进行评估后，利用方差分析中的变异系数（CV）计算出整个组和性别的BV估计值，置信区间为95%。游离κ、游离λ和游离κ/λ比值的受试者内BV （CVI）估计值分别为9.2%、8.6%和6.6%。游离κ、游离λ和游离κ/λ比值的受试者间BV （CVG）估计值分别为24.6%、26.6%和17.5%。血清游离LCs的游离κ和游离κ/λ比值及CVG差异无统计学意义。游离LCs及其κ/λ比值表现出明显的个性。游离κ、游离λ和游离κ/ λ比的理想不精确性和偏差的分析性能指标（aps）分别为3.9% - 5.4%、4.3% - 5.8%和2.9% - 4.6%。本研究为血清游离（κ和λ）和游离κ/λ比值提供了最新的、特性良好的BV估计，为定义aps提供了必要的数据。κ和λ的个别性强调了优先考虑参考变化值而不是传统参考区间的重要性，以改善临床实践中的诊断和监测。

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来源期刊

Clinica Chimica Acta 医学-医学实验技术

CiteScore

10.10

自引率

2.00%

发文量

1268

审稿时长

23 days

期刊介绍： The Official Journal of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Clinica Chimica Acta is a high-quality journal which publishes original Research Communications in the field of clinical chemistry and laboratory medicine, defined as the diagnostic application of chemistry, biochemistry, immunochemistry, biochemical aspects of hematology, toxicology, and molecular biology to the study of human disease in body fluids and cells. The objective of the journal is to publish novel information leading to a better understanding of biological mechanisms of human diseases, their prevention, diagnosis, and patient management. Reports of an applied clinical character are also welcome. Papers concerned with normal metabolic processes or with constituents of normal cells or body fluids, such as reports of experimental or clinical studies in animals, are only considered when they are clearly and directly relevant to human disease. Evaluation of commercial products have a low priority for publication, unless they are novel or represent a technological breakthrough. Studies dealing with effects of drugs and natural products and studies dealing with the redox status in various diseases are not within the journal''s scope. Development and evaluation of novel analytical methodologies where applicable to diagnostic clinical chemistry and laboratory medicine, including point-of-care testing, and topics on laboratory management and informatics will also be considered. Studies focused on emerging diagnostic technologies and (big) data analysis procedures including digitalization, mobile Health, and artificial Intelligence applied to Laboratory Medicine are also of interest.