Guidelines for the correct use of the nomenclature of biochemical indices of bone status: a position statement of the Joint IOF Working Group and IFCC Committee on Bone Metabolism
-
Giovanni Lombardi
,
Niklas Rye Jørgensen
,
Nicholas C. Harvey
,
Eugene V. McCloskey
,
Kristina E. Åkesson
,
Richard Eastell
,
Patrick Garnero
,
John A. Kanis
,
Patricia Khashayar
,
Nancy E. Lane
Abstract
The presented guidelines are an update of the position paper, endorsed by the International Osteoporosis Foundation (IOF), on nomenclature of bone markers published over 2 decades ago. Novel insight into bone biology and pathophysiology of bone disorders has highlighted the increasing relevance of new and known mediators implicated in various aspects of bone metabolism. This updated guideline proposes the nomenclature Bone Status Indices (BSI) as the comprehensive classification rather than bone turnover markers, bone markers, metabolic markers of bone turnover or metabolic markers of bone turnover, that are currently in use for the implicated molecules. On behalf of the IFCC Committee on Bone Metabolism and the Joint IOF Working Group and IFCC Committee on Bone Metabolism, the authors propose standardized nomenclature, abbreviations and measurement units for the bone status indices.
Introduction
In 2000, Pierre D. Delmas, during his term in office as the President of the International Osteoporosis Foundation (IOF), together with a group of other experts, authored an IOF endorsed position paper proposing the standardisation of the nomenclature of bone markers [1]. The main aim of the paper, also published in Clinical Chemistry, was “to avoid confusion in the literature, given the growing number of various assays, especially for measurement of bone resorption” [2], 3]. Until today, the objective of consistency and uniformity in the use of the nomenclature proposed by Delmas has not been realized. Laboratories continue to use the terms and abbreviations at their own discretion without consistency or uniformity. Furthermore, there is a lack of standardisation in naming of new markers, especially several regulatory molecules, for which various terms have been used in studies to name the same markers. An example is given by osteocalcin, that is also called bone gla-protein, and is abbreviated as OC, OCN, BGLAP [4]. This inconsistency, along with the rejection, in practice, by some journals, to use the proposed nomenclature, has compelled authors to report the various aliases pertaining to the marker studied. In the era of big data sharing, it is inconceivable that either a molecule can be called differently, or different molecules share the same name. Again, the example comes from osteocalcin: it can exist in different forms with different degree of carboxylation, from zero to three; however, these forms are overall called osteocalcin or, sometimes, uncarboxylated or undercarboxylated osteocalcin [4]. Further, the abbreviation CTX-I (carboxyterminal collagen type I crosslinks) often is used indiscriminately to indicate α-CTX-I, β-CTX-I and the CTX generated by matrix metalloproteinases activity [5]. The need for uniformity in nomenclature is driven by the need for comparability of the results among studies. These and other factors justify the need for an update and revision of the previous position paper.
The first step in standardising nomenclature is the provision of a collective names for these indices. A considerable body of literature refers to these markers as “bone turnover markers”, “bone markers”, “metabolic markers of bone turnover” or “biochemical markers of bone turnover”. Each idiom contemplates specific, but not comprehensive, aspects of the functions of the molecules involved. Indeed, the term “turnover”, specifically identifies a process of replacement of “old”, functionally impaired (or less efficient) components by newly synthesised molecules and is mainly associated with structural elements [6]. On the other hand, the term “metabolic” refers to the anabolic-versus-catabolic activity of bone cells. Even in this case it refers to the structural and enzymological aspects, completely excluding any regulatory, hormonal and elemental mediators [6]. Finally, these terms include only bone-derived molecules disregarding indices or mediators originating from other tissues and yet importantly affecting bone cell metabolism and bone matrix turnover are considered [7].
Based on these considerations we propose the alternative term Bone Status Indices (BSIs) to better embrace the entire set of molecules, including structural components, side products of either anabolic or catabolic activities, regulatory molecules, enzymatic activities, and hormones that altogether contribute to defining the status of the skeleton.
The current advances in automation and the inflexibility of laboratory software in usable characters for acronyms are other aspects to be considered. As these acronyms will be included in laboratory reports, uniformity will help readers, patients and physicians by simplifying the retrieval of related information from specialised sources and avoid potential misunderstanding and erroneous interpretations.
The updated guidelines thus take into consideration all those additional indices that are related to bone status but do not originate from the bone.
Finally, the issue of measurement units, although not directly related to the nomenclature, is associated to the need of standardisation of laboratory reports. As for indices’ names, the units frequently used mostly reflect habits, often at the national level, and very often do not adhere to the standards of the International System of Units (SI).
The aim of this report, written on behalf of the Joint International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Committee on Bone Metabolism and the IOF Working Group on Bone Metabolism, is to propose a comprehensively revised nomenclature of the BSIs with appropriate abbreviations as well as the correct measurement unit, based on the indication of the SI. As described above, the field of bone-related markers has been enlarged, in the last years, to newly discovered molecules and to already known mediators with newly discovered roles in bone structure and metabolism. Most of these are currently used in diagnostics while others have a diagnostic potential that might justify their clinical implementation in the future. Therefore, since the variety of roles and origin of the components which measurements are useful in determining the bone status, nomenclature and related issues will be treated separately for three main groups of markers: i) bone turnover markers, ii) bone cells’ enzymes and iii) regulatory molecules.
Recommended nomenclature for bone status indices (BSIs)
Bone status indices (BSIs) have been categorised based on the general process they belong to: i) bone turnover markers, ii) bone cells’ enzymes or iii) regulatory molecules.
Table 1 reports the main information related to grouping, nomenclature and recommended units of measurement.
Recommended nomenclature (and related acronyms), grouping and measurement unit for BSIs.
| Category | Group/Family | Recommended name [UniProt/Expasy recommended name, UniProt/Expasy/PubChem ID]a | Used acronyms (acronyms marked withb are explained in the footnote) | Recommended acronym | Recommended unit |
|---|---|---|---|---|---|
| Bone turnover markers | Type I collagen propeptides | Procollagen type I N-propeptide | PINP, P1NP | PINP | µg/L |
| Intact procollagen type I N-propeptide (trimer) | Intact PINP, intact P1NP, iPINP, iP1NP | iPINP | µg/L | ||
| Procollagen type I N-propeptide (trimer + monomer) | Total PINP, total P1NP, tPINP, tP1NP | tPINP | µg/L | ||
| Procollagen type I C-propeptide | PICP, P1CP | PICP | µg/L | ||
| Type I collagen cross-linked telopeptides | N-terminal telopeptide of type I collagen | NTX-I, NTX-1, NTx-I, NTx-1 | NTX-I | µg/L (serum/plasma, urine) | |
| α-isomerized C-terminal telopeptide of type I collagen | α-CTX-I, α-CTx-I, α-CTX-1, α-CTx-1, αCTX-I, αCTx-I, αCTX-1, αCTx-1, aplhaCTX-I, aplhaCTx-I, aplhaCTX-1, aplhaCTx-1 | α-CTX-I (a-CTX-I)e | µg/L (serum/plasma/urine) | ||
| β-isomerized C-terminal telopeptide of type I collagen | β-CTX-I, β-CTx-I, β-CTX-1, β-CTx-1, βCTX-I, βCTx-I, βCTX-1, βCTx-1, betaCTX-I, betaCTx-I, betaCTX-1, betaCTx-1, crosslaps, beta crosslaps | β-CTX-I (b-CTX-I)e | ng/L | ||
| C-terminal cross-linking telopeptide of type I collagen generated by MMPs (matrix metalloproteinases) | CTX-MMP, ICTP | CTX-I-MMP | µg/L | ||
| Bone cells’ enzymes | Alkaline phosphatase | (Total tissue non-specific) alkaline phosphatase [UniProt: Alkaline phosphatase, tissue-nonspecific isozyme-P05186] | ALP, tnsALP, AP, TNAP | ALP | U/L |
| Bone-specific alkaline phosphatase (mass concentration) | BALP, bone ALP, BAP, BSAP | BALP | µg/L | ||
| Bone-specific alkaline phosphatase (catalytic activity) | U/L | ||||
| Acid phosphatase | Acid phosphatase [UniProt: Tartrate-resistant acid phosphatase type 5-P13686] | ACP | ACP | U/L | |
| Tartrate-resistant acid phosphatase isoform 5b [UniProt: Tartrate-resistant acid phosphatase type 5-P13686] | TRACP5b, TRAP5b | TRACP5b | U/L | ||
| Cathepsin K | Cathepsin K [UniProt: Cathepsin K-P43235] | CTSK | CTSK | µg/L | |
| Regulatory molecules | Osteocalcin formsc | Osteocalcin (total) | OC, OCN, BGLAP, B-GLAP, bone-gla-protein | OC | µg/L |
| Intact osteocalcin [UniProt: Osteocalcin-P02818] | iOC, intact OC | iOC | µg/L | ||
| N-mid fragment of osteocalcin | NmidOC, Nmid-OC, N-ter–mid OC | NmidOC | µg/L | ||
| Fully carboxylated osteocalcin | / | γ3OC (g3OC)e | µg/L | ||
| Undercarboxylated osteocalcin | / | γ2OC (g2OC)e
γ1OC (g1OC)e |
µg/L | ||
| Uncarboxylated osteocalcin | / | γ0OC (g0OC)e | µg/L | ||
| Vitamin D metabolites | Vitamin D (total)
|
vitD
|
vitD
|
nmol/L, µg/L | |
| Calcidiol 25-(OH) vitamin D (total)
|
25-(OH)D
|
25-(OH)D
|
nmol/L, µg/L |
||
| Free calcidiol Free 25-(OH) vitamin D (total)
|
f25-(OH)D
|
f25-(OH)D
|
pmol/L, ng/L |
||
| Calcitriol 1,25-(OH)2 vitamin D (total)
|
1,25-(OH)2D
|
1,25-(OH)2D
|
pmol/L, ng/L |
||
| Free calcitriol Free 1,25-(OH)2 vitamin D (total)
|
f1,25-(OH)2D
|
f1,25-(OH)2D
|
pmol/L, ng/L |
||
24,25-(OH)2 vitamin D (total)
|
24,25-(OH)2D
|
24,25-(OH)2D
|
nmol/L, µg/L | ||
3-epi-25-(OH) vitamin D (total)
|
3-epi-25-(OH)D
|
3-epi-25-(OH)D
|
nmol/L, µg/L | ||
1,24,25-(OH)3 vitamin D (total)
|
1,24,25-(OH)3D
|
1,24,25-(OH)3D
|
pmol/L, ng/L | ||
25-(OH) vitamin D-26,23-lactone (total)
|
25-(OH)D-26,23-lactone
|
25-(OH)D-26,23-lactone
|
nmol/L, µg/L | ||
| Vitamin D-binding protein [UniProt: Vitamin D-binding protein-P02774] | VDBP, VBP, VitD-BP, DBP, VDB | VDBP | μmol/L | ||
| Parathyroid hormone | Parathyroid hormone (previously intact PTH) [UniProt: Parathyroid hormone-P01270] | PTH, intact PTH, iPTH | PTH | pmol/L, ng/L | |
| 1-84 Parathyroid hormone | 1-84PTH, PTH1-84, PTH(1–84) | 1-84PTH | pmol/L, ng/L | ||
| Fibroblast growth factor 23 | Intact fibroblast growth factor 23 [UniProt: Fibroblast growth factor 23-Q9GZV9] | iFGF23, intact FGF23 | iFGF23 | ng/L | |
| C-terminal FGF23 | cFGF23, C-terminal FGF23, C-ter FGF23 | cFGF23 | RU/Ld | ||
| Wnt signalling pathway inhibitors | Sclerostin [UniProt: Sclerostin-Q9BQB4] | Sclerostin, SOST | Sclerostin | ng/L | |
| Dickkopf-related protein 1 [UniProt: Dickkopf-related protein 1-O94907] | Dkk-1, Dkk1, DKK-1, DKK1 | DKK-1 | ng/L | ||
| Tumour necrosis factor superfamily | Receptor activator of nuclear factor κB ligand [UniProt: Tumour necrosis factor ligand superfamily member 11-O14788] | RANKL, TNFSF11b, TRANCEb, OPGLb, ODFb | RANKL | ng/L | |
| Receptor activator of nuclear factor κB [UniProt: Tumour necrosis factor receptor superfamily member 11A-Q9Y6Q6] | RANK, TNFRSF11Ab, TRANCE receptor | RANK | µg/L | ||
| Osteoprotegerin [UniProt: Tumour necrosis factor receptor superfamily member 11B-O00300] | OPG, TNFRSF11Bb, OCIFb | OPG | ng/L | ||
| Factors involved in cell migration and adhesion | Secreted protein acidic and rich in cysteine [UniProt: SPARC-P09486] | SPARC, osteonectin, ONb, BM-40b | SPARC | ng/L | |
| Osteopontin [UniProt: Osteopontin-P10451] | OPN, BSP-1b, BNSPb, ETA-1b, SPP1b, Ricb | OPN | ng/L | ||
| Periostin [UniProt: Periostin-Q15063] | PSTN, POSTN, PN, OSF-2b | PSTN | ng/L | ||
| Periostin fragment generated by cathepsin K | kPSTN, kPOSTN | kPSTN | µg/L |
-
aIf available. bTNFSF11, tumour necrosis factor ligand superfamily member 11. TRANCE, TNF-related activation-induced cytokine; OPGL, osteoprotegerin ligand; ODF, osteoclast differentiation factor; TNFRSF11A, tumour necrosis factor receptor superfamily member 11A; TNFRSF11B, tumour necrosis factor receptor superfamily member 11B; OCIF, osteoclastogenesis inhibitory factor; ON, osteonectin; BM-40, basement-membrane protein 40; BSP-1, bone sialoprotein 1; BNSP, bone sialoprotein; ETA-1, early T-lymphocyte activation 1; SPP1, secreted phosphoprotein 1; Ric, Rickettsia resistance; OSF-2, osteoblast-specific factor 2. cNomenclature is referred to the commercially available assays. dThis is a procedure-defined unit. eIn case the IT, system does not allow to use the Greek letters, it possible to substitute them with the Latin counterpart.
Comments on Tables
Here are some considerations that should be taken into account for a correct contextualization of the information reported in Table 1.
CTX-I corresponds to the C-terminal octapeptide sequence of α1 chain of type I collagen (EKAHDGGR) [8]. β-CTX-I (EKAHD-β-GGR) results from the β-isomerization of α-CTX-I, i.e., transfer of the peptide bound between aspartic acid (D) residues and the adjacent amino acid from the α-carboxyl group to the β-carboxyl group. The ratio between native (α-CTX-I) and isomerized β-CTX-I estimates the extent of type I collagen isomerization in bone. Due to high turnover in growing subjects, the equilibrium of isomerization cannot be achieved, resulting in a relatively higher α/β-CTX-I; once reached the peak bone mass (>20 years of age) since the rate of bone remodelling is slower than isomerization, the equilibrium is achieved, resulting in a fairly constant α/β-CTX-I ratio [9]. a-CTX-I and b-CTX-I can be used in case the IT system does not allow to use the Greek letters.
The CTX-I-MMP epitope (GPPSAGFDFSFLPQPPQEKAHDGGR) is a larger conformational epitope, than CTX-I, including at least two telopeptides and the first phenylalanine (F) of the phenylalanine -rich region; cathepsin K degrades CTX-I-MMP to generate CTX-I [10].
The term CTX-I-MMP is recommended instead of C-terminal telopeptide of type I collagen (ICTP).
Since BALP is an enzyme, the activity should be measured. However, due to the heterogeneity of the commercially available assay kits, measurement in terms of mass concentration is acceptable. Based on UK-NEQAS results, U/L could be converted into µg/L, and vice versa, according to the following equations [11]:
However, the use of these equations is strongly discouraged since their reliability is scarce.
Osteocalcin exists in the circulation in different forms, associated with a different degree of carboxylation and/or resulting from proteolytic cleavage that can be assessed by different assays [4]. Therefore, the term osteocalcin (OC) refers to the total amount of OC, i.e., the sum of intact and fragmented OC fractions regardless of their degree of carboxylation. The terms iOC and NmidOC refers only to the intact and the N-terminal plus the mid-fragment (the most abundant circulating fragment), respectively. Regarding the carboxylation in position γ (“g” can be used in case the IT system does not allow to use the Greek letters) of the glutamic acid residues (19, 21 and 24), the two limit forms should be named γ3OC (g3OC), the fully carboxylated one, and γ0OC (g0OC), the fully uncarboxylated one. Finally, the intermediate forms of carboxylation, i.e., those bearing either 1 or 2 carboxylic groups, should be named γ1OC (g1OC) and γ2OC (g2OC), respectively, regardless of the position of the glutamic acid residue(s) within the protein sequence.
Vitamin D metabolites mass concentration must be expressed as nmol/L or µg/L and pmol/L or ng/L, according to [12]. Traditional units, such as ng/mL or pg/mL should be avoided. Vitamin D metabolites ratios (VMRs) are calculated parameters. It is recommended to measure both analytes simultaneously in one sample using the same analytical technique, preferably LC-MS/MS [13]. To unify VMRs’ results, we recommend the expression as a % for the following VMRs, although recently often used ratios are opposite to and in absolute values [14]. The term VMR is often used for 24,25-(OH)2D/25-(OH)D ratio but due to possible confusion with others VMRs, the metabolite type should be always mentioned, e.g., VMR (24,25/25) [15], 16].
Use mass concentration units for VMR calculations.
Table 2 reports the conversion formulas (µg/L to nmol/L and ng/L to pmol/L) for vitamin D metabolites.
Intact PTH is a misleading term now and should no longer be used. Parathyroid hormone (PTH) term includes 2nd generation PTH assays (intact PTH) that use detection antibodies against N-terminus (amino acids 12–24 or 26–32). For immunoassays, the term 1-84PTH is reserved for 3rd generation PTH assays (bioactive PTH or whole PTH) that use detection antibodies against N-terminus (amino acids 1–4). These assays also cross-react with amino-PTH. PTH and 1-84PTH assays results differ significantly, at least in standards used and therefore we recommend to use terms PTH for 2nd generation PTH assays and 1-84PTH for 3rd generation PTH assays. For fragments measured by LC-MS/MS or HRMS, the measured fragments should be stated in brackets, e.g., (x–y)PTH. Use following PTH conversion factors:
Conversion formulas for vitamin D metabolites.
| Analyte | MW | Conversion formulas |
|---|---|---|
| vitamin D2 (ergocalciferol) | 396.60 | nmol/L=2.52 * µg/L |
| vitamin D3 (cholecalciferol) | 384.60 | nmol/L=2.60 * µg/L |
| 25-(OH) vitamin D2 | 412.60 | nmol/L=2.42 * µg/L |
| 25-(OH) vitamin D3 | 400.64 | nmol/L=2.50 * µg/L |
| free 25-(OH) vitamin D2 | 412.60 | pmol/L=2.42 * ng/L |
| free 25-(OH) vitamin D3 | 400.64 | pmol/L=2.50 * ng/L |
| 1,25-(OH)2 vitamin D2 | 428.60 | pmol/L=2.33 * ng/L |
| 1,25-(OH)2 vitamin D3 | 416.60 | pmol/L=2.40 * ng/L |
| free 1,25-(OH)2 vitamin D2 | 428.60 | pmol/L=2.33 * ng/L |
| free 1,25-(OH)2 vitamin D3 | 416.60 | pmol/L=2.40 * ng/L |
| 24,25-(OH)2 vitamin D2 | 429.00 | nmol/L=2.33 * µg/L |
| 24,25-(OH)2 vitamin D3 | 416.63 | nmol/L=2.40 * µg/L |
| 3-epi-25-(OH) vitamin D2 | 412.65 | nmol/L=2.42 * µg/L |
| 3-epi-25-(OH) vitamin D3 | 400.64 | nmol/L=2.50 * µg/L |
| 1,24,25-(OH)3 vitamin D2 | 444.64 | pmol/L=2.25 * ng/L |
| 1,24,25-(OH)3 vitamin D3 | 432.60 | pmol/L=2.31 * ng/L |
| 25-(OH) vitamin D2-26,23-lactone | 440.60 | nmol/L=2.27 * µg/L |
| 25-(OH) vitamin D3-26,23-lactone | 428.60 | nmol/L=2.25 * µg/L |
Conclusions
In this paper, we propose a revised guideline for the nomenclature of circulating markers useful to monitor both the metabolic activity of bone cells and the regulatory mediators that intervene in different aspects of bone cell biology, from differentiation, to migration, mechanosensing, mineral metabolism, and extracellular matrix dynamics.
Considering the diverse role of these compounds, the general terms bone turnover markers and metabolic markers of bone turnover no longer fully cover their biological roles. Therefore, the term Bone Status Indices (BSIs) is proposed as a more comprehensive terminology.
Acknowledgments
The authors would like to thank the members of the Joint IOF Working Group and IFCC Committee on Bone Metabolism: Vincent Delatour, Karen Phinney, and Cathie Sturgeon (consultants); Markus Herrmann, Jean-Paul Cristol, Edgard Delvin, Masakazu Miura, Aylin Sepici Dinçel and Galina Zemtsovskaja (national representatives); Kristina Åkesson, Nasser Al-Daghri, Cyrus Cooper, Richard Eastell, Joseph Foldes, Patrick Garnero, John A. Kanis, Patricia Khashayar, Nancy Lane, Michael McClung, Stuart Silverman. Members of the IFCC Scientific Committee on Nomenclature, Properties and Units (C-NPU) in collaboration with International Union of Pure and Applied Chemistry (IUPAC): Young Bae Hansen, Rebecca Ceder, Sridevi Deveraj, Koh Furuta, Fatma Meric Yilmaz, Gunnar Nordin; Aracelis Germán, Naohito Ishii, Dalius Vitkus, Aaron Ojule, Karin Toska, Valentina Naztmutdinova, Nada Majkic-Singh, Carlos Lacava (consultants and national representatives). The authors are grateful to the International Osteoporosis Foundation (IOF) Committee of Scientific Advisors for their endorsement of this position paper.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest related to this article.
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Research funding: None declared.
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Data availability: Not applicable.
References
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- Analytical characteristics and performance of a new hs-cTnI method: a multicenter-study
- Diabetes
- Use of labile HbA1c as a screening tool to minimize clinical misinterpration of HbA1c
- Letters to the Editor
- Current trends and future projections in the clinical laboratory test market: implications for resource management and strategic planning
- Particulate matter in water: an overlooked source of preanalytical error producing erroneous chemistry test results
- “Activation” of macro-AST by pyridoxal-5-phosphate in the assay for aspartate aminotransferase
- The correlation of albumin with total protein concentrations in cerebrospinal fluid across three automated analysers – relevance to the diagnosis of subarachnoid haemorrhage in clinical chemistry practice
- Adult reference intervals for serum thyroid‐stimulating hormone using Abbott Alinity i measuring system
- Cell population data in venous thrombo-embolism and erysipelas: a potential diagnostic tool?
- Diagnostic performances and cut-off verification of blood pTau 217 on the Lumipulse platform for amyloid deposition in Alzheimer’s disease
- The first case of Teclistamab interference with serum electrophoresis and immunofixation
- Congress Abstracts
- Annual meeting of the Royal Belgian Society of Laboratory Medicine (RBSLM): “A Neurological Journey: Brain Teasers for Laboratory Medicine”
Articles in the same Issue
- Frontmatter
- Editorial
- Beyond test results: the strategic importance of metadata for the integration of AI in laboratory medicine
- Reviews
- Reference, calibration and referral laboratories – a look at current European provisions and beyond
- How has the external quality assessment/proficiency testing of semen analysis been developed in the past 34 years: a review
- Opinion Papers
- Data flow in clinical laboratories: could metadata and peridata bridge the gap to new AI-based applications?
- A comprehensive survey of artificial intelligence adoption in European laboratory medicine: current utilization and prospects
- Guidelines and Recommendations
- Guidelines for the correct use of the nomenclature of biochemical indices of bone status: a position statement of the Joint IOF Working Group and IFCC Committee on Bone Metabolism
- Candidate Reference Measurement Procedures and Materials
- Absolute quantitation of human serum cystatin C: candidate reference method by 15N-labeled recombinant protein isotope dilution UPLC-MS/MS
- General Clinical Chemistry and Laboratory Medicine
- Performance evaluation of the introduction of full sample traceability system within the specimen collection process
- Pre-analytical stability of haematinics, lactate dehydrogenase and phosphate in whole blood at room temperature up to 24 h, and refrigerated serum stability of lactate dehydrogenase, folate and vitamin B12 up to 72 h using the CRESS checklist
- Comparison of capillary finger stick and venous blood sampling for 34 routine chemistry analytes: potential for in hospital and remote blood sampling
- Performance evaluation of enzymatic total bile acid (TBA) routine assays: systematic comparison of five fifth-generation TBA cycling methods and their individual bile acid recovery from HPLC-MS/MS reference
- Clinical performance of a new lateral flow immunoassay for xylazine detection
- Evaluation of revised UK-NEQAS CSF-xanthochromia method for subarachnoid hemorrhage: outcome data provide evidence for clinical value
- Strategies to verify equimolar peptide release in mass spectrometry-based protein quantification exemplified for apolipoprotein(a)
- Evaluation of the clinical performance of anti-mutated citrullinated vimentin antibody and 14-3-3 eta testing in rheumatoid arthritis
- Diagnostic performance of specific biomarkers for interstitial lung disease: a single center study
- Reference Values and Biological Variations
- Neonatal reference intervals for serum steroid hormone concentrations measured by LC-MS/MS
- Paediatric reference intervals for haematology parameters analysed on Sysmex XN-9000: a comparison of methods in the framework of indirect sampling
- Cardiovascular Diseases
- Analytical characteristics and performance of a new hs-cTnI method: a multicenter-study
- Diabetes
- Use of labile HbA1c as a screening tool to minimize clinical misinterpration of HbA1c
- Letters to the Editor
- Current trends and future projections in the clinical laboratory test market: implications for resource management and strategic planning
- Particulate matter in water: an overlooked source of preanalytical error producing erroneous chemistry test results
- “Activation” of macro-AST by pyridoxal-5-phosphate in the assay for aspartate aminotransferase
- The correlation of albumin with total protein concentrations in cerebrospinal fluid across three automated analysers – relevance to the diagnosis of subarachnoid haemorrhage in clinical chemistry practice
- Adult reference intervals for serum thyroid‐stimulating hormone using Abbott Alinity i measuring system
- Cell population data in venous thrombo-embolism and erysipelas: a potential diagnostic tool?
- Diagnostic performances and cut-off verification of blood pTau 217 on the Lumipulse platform for amyloid deposition in Alzheimer’s disease
- The first case of Teclistamab interference with serum electrophoresis and immunofixation
- Congress Abstracts
- Annual meeting of the Royal Belgian Society of Laboratory Medicine (RBSLM): “A Neurological Journey: Brain Teasers for Laboratory Medicine”
