International Federation Of Clinical Chemistry Research Articles

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript.The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

A Retrospective Observational Study to Assess the Quality Management System in a Molecular Diagnostic Laboratory of a COVID-19 Dedicated Hospital in Delhi, India

Introduction: A molecular diagnostic laboratory is the cornerstone of Coronavirus Disease-2019 (COVID-19) disease diagnosis, as the patient’s treatment and management protocol depend on molecular results. Therefore, the laboratory conducting these tests must adhere to quality management process to increase the accuracy and validity of the generated reports. Rajiv Gandhi Super Speciality Hospital established its molecular diagnostic set-up at the beginning of the pandemic. Hence, this study aims to generate quality management data to help improve weak points. Aim: To assess the quality management system for COVID-19 diagnosis. Materials and Methods: This retrospective observational study was conducted at Rajiv Gandhi Super Speciality Hospital in Delhi, India. A total of 14,561 samples were collected over six months, from February 2021 to July 2021. Data from all samples received during this period for COVID-19 ReverseTranscriptase Polymerase Chain Reaction (RT-PCR) testing were included. Data were retrospectively collected from the electronic Laboratory Information Management System (LIMS). Quality variables were analysed over six months from July to December 2021 and classified into preanalytical, analytical, and postanalytical variables. Quality Indicators (QIs) were selected from a common model of QIs set by the International Federation of Clinical Chemistry and Laboratory Medicine. The results were presented in percentages, and descriptive statistics were analysed using Statistical Package for Social Sciences (SPSS) software. Results: During the six-month study period, the molecular laboratory received 14,561 samples. Among the preanalytical variables, sample leakage was the most common cause of sample rejection (134 samples, 0.92%), followed by the non generation of Specimen Referral Form (SRF) identification (76 samples, 0.52%), and non compliance with triple packaging (44 samples, 0.3%). Other preanalytical aspects assessed included incomplete patient identification (17 samples, 0.11%), insufficient sample quantity (12 samples, 0.08%), missing forms/samples (7 samples, 0.04%), samples in the wrong vials/ empty Viral Transport Media (VTM) tubes (5 samples, 0.03%), and incomplete LIMS entry (2 samples, 0.01%). Internal Quality Control (QC) was not obtained in 55 samples (0.37%), and two incidents of cross-contamination resulted in false-positive results. Among the postanalytical factors, 11 samples (0.07%) could not be dispatched within the stipulated time frame. Conclusion: The assessment of the quality management system revealed some areas for improvement, emphasising the importance of adhering to QC processes for the smooth operation of diagnostic laboratories, especially those involved in critical reporting. The assessment of QIs helped monitor laboratory parameters effectively.

Cadmium, manganese, mercury and lead in the general adult population of Kinshasa, DR Congo

Background and Aim. Many metals are of health concern due to their toxic proprieties and health impairments in the human body. To evaluate values for the internal exposure in the general population, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and the International Union of Pure and Applied Chemistry (IUPAC), recommend the use of reference intervals (RIs) of metals as an indicator of the background exposures. This work aimed to derive RIs for Cd, Hg, Mn and Pb in the blood and urine of the adult population living in Kinshasa (n = 396, aged 18–70 years with 210 females). Methods. Levels of metals were measured using Inductively Coupled Argon Plasma - Mass Spectrometry (ICP-MS). Results. In blood, the proposed RIs [P5-P95 (GM)] were 0.089–2.365 µg/L (0.262), 41.41–199.20 µg/L (84.43), 0.100–1.964 µg/L (0.450) and 6.014–15.380 µg/L (9.394) for Cd, Pb, Hg and Mn, respectively. Urinary levels [(P5-P95 (GM)] were 0.142–1.430 µg/L (0.458) for Cd, 1.910–17.840 µg/L (5.424) for Pb, 0.349–2.295 µg/L (0.816) for Hg and 0.063–1.340 µg/L (0.188) for Mn. Conclusion. Except for Pb, levels of all metals were significantly lower than those found in the same city in 2012 and similar to databases involving non-occupationally exposed populations from other countries, probably due to exclusion criteria of metal exposure applying in the present survey (occupationally exposed to the studied metals, smoking habits, amalgam tooth fillings, fish consumption habit more than one time per week, etc.). These background metal exposures will be useful for future occupational and/or environmental surveys as well as undertaking a reliable regulation of chemical exposure in Kinshasa via a national HBM program.

Osteoporosis: Investigations and Monitoring.

Osteoporosis is characterized by microarchitectural disruption of the bone, decrease in bone mineral density, and increased skeletal fragility and risk of fracture. Osteoporosis occurs due to the decoupling of bone formation and bone resorption, with a significant increase in resorption. This review article focuses on the role of laboratory investigations in the diagnosis and monitoring of treatment in patients with osteoporosis. This review article collected literature from various databases using keywords such as 'Laboratory investigations', 'Osteoporosis', 'Diagnosis', 'Monitoring', and 'Bone turnover markers'. Laboratory investigations, including serum calcium, alkaline phosphatase, vitamin D, and parathormone, are commonly performed tests to exclude secondary causes of osteoporosis and monitor the response to therapy. The biochemical markers of bone turnover are newly emerged tests for monitoring individual patients with osteoporosis. These markers are classified as bone formation and resorption markers, measurable in both serum and urine. The use of these markers is limited by biological and analytical variability. The International Federation of Clinical Chemistry and Laboratory Medicine and the International Osteoporosis Foundation recommend serum procollagen type 1 amino-terminal propeptide as the bone formation marker and β-form of C-terminal cross-linked telopeptide of type I collagen (β-CTx-1/β-CrossLaps) as the marker of choice, using standardized procedures. However, in specific cases, such as patients with chronic renal disease, CTx-1 is replaced by the resorption marker tartrate-resistant acid phosphatase 5b, as its levels are not affected by renal excretion. Bone turnover markers have emerged as tools for the assessment of osteoporosis, using standardized procedures, and are useful in monitoring therapy and treatment compliance.

Innovations in HbA1c analysis: finding the balance between speed and accuracy. An investigation of a potential new Secondary Reference Measurement Procedure for the IFCC.

The escalating prevalence of diabetes worldwide has resulted in a dramatic increase in the number of people who need testing, which in turn necessitates faster HbA1c measurement. The Tosoh GR01 addresses the need for fast turnaround times of whilst offering pragmatic steps to maintain result accuracy in a single instrument by offering two distinct operating modes: Short Mode (SM) and Long Mode (LM). The aim of this study was to evaluate all relevant aspects of the performance of the Tosoh GR01 with a view to accepting the instrument as a future Secondary Reference Measurement Procedure (SRMP) for the IFCC. Certified Clinical & Laboratory Standards Institute (CLSI) Evaluation Protocols (EP) were used to evaluate precision (EP-5), accuracy (EP-9), linearity (EP-6), carry-over (EP-10) and the effect of hemoglobin variants and other potential interferences. Both modes demonstrated CVs <0.6 % in SI units and <0.4 % in NGSP units at 46 mmol/mol (6.4 %) and 75 mmol/mol (9.0 %) and passed both National Glycohemoglobin Standardization Program (NGSP) and International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) certification procedures when compared with 7 IFCC Certified Secondary Reference Measurement Procedures (SRMP). Sigma for both modes was >6 when using the results of EP-5 and EP-9 at an HbA1c concentration of 50 mmol/mol (6.7 %). Neither mode showed any interference with common Hb-variants except for HbAE when HbA1c was >65 mmol/mol. In the SM HbAS, HbAD and HbAC were recognized but no result was reported. There is a good balance between speed and accuracy for determining HbA1c with the Tosoh GR01 in both analytical modes and the device is suitable for use as an IFCC SRMP.

The LEAP checklist for Laboratory Evaluation and Analytical Performance Characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

The LEAP checklist for Laboratory Evaluation and Analytical Performance characteristics reporting of clinical measurement procedures

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript.The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures.

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures.

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the Laboratory Evaluation and Analytical Performance Characteristics (LEAP) checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures.

Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers, and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.

FRI485 High Interlaboratory Variability In Free Thyroxine Measurement Indicates Need For Method Standardization

Abstract Disclosure: A. Ribera: None. U. Danilenko: None. O. Sugahara: None. L. Collins: None. T. Buchannan: None. N. Vazquez: None. F. Pokuah: None. D. Wirtz: None. L. Zhang: None. A.N. Lyle: None. H.W. Vesper: None. Thyroid function tests are critical to diagnose diseases of the thyroid. Concerns about the accuracy and reliability of thyroid function tests, especially free thyroxine (FT4), have been stated by the clinical laboratory community for many years. In response to these concerns, the CDC Clinical Standardization Program (CSP) has created a standardization program for FT4 based on the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference system and is partnering with IFCC to standardize FT4 and harmonize TSH testing globally. As part of this program, CDC developed an accurate and sensitive reference measurement procedure (RMP) to assign reference values to individual donor sera. Assay manufacturers and research and clinical laboratories can use these sera to assess the analytical performance of their measurements, and monitor analytical performance over time. To obtain initial information about the analytical performance of FT4 and TSH measurements, an interlaboratory study among commercial assays and laboratory developed test was conducted. A panel of 40 blinded, fresh-frozen single donor patient serum samples with FT4 concentration ranging between 11-32 pmol/L concentrations was measured by participants and compared to the results obtained by CDC RMP for FT4. In addition, commercial assay manufacturers were asked to measure thyroid-stimulating hormone (TSH). Results from sixteen commercial assays and four laboratory developed test (LDT) participated. Preliminary results indicate a negative mean bias for all commercial FT4 assays ranging from -34.46% to -5.08%. Some of the assays agreed more closely to the RMP than others (four assays had mean bias over -25%). An equilibrium dialysis mass spectrometry-based assays had mean biases ranging from -8.86% to - 1.72% agreeing well with RMP. The data suggest that the observed bias can be effectively minimized through recalibration to the RMPs operated by the CDC CSP and the IFCC reference laboratory network. The mean TSH concentrations ranged from 0.34 to 21.56 uIU/mL with mean %CV of 11.42% (95%CI 8.07%-14.76%) suggesting good agreement between various platforms. Findings from this study will be used to customize CDC’s protocols and procedures for standardizing FT4 measurements. Presentation: Friday, June 16, 2023

A-023 Performance Evaluation of the Atellica IM High-Sensitivity Troponin I Assay on the Atellica CI 1900 Analyzer

Abstract Background The Atellica® CI 1900 Analyzer is an automated, high-throughput, integrated chemistry and immunoassay analyzer employing both Atellica CH and Atellica IM assays. This study was designed to evaluate the analytical performance of the Atellica IM High Sensitivity Troponin I (TnIH) assay* on the Atellica CI 1900 Analyzer*. Methods Precision and method comparison were used as performance indicators for the Atellica CI 1900 Analyzer. Precision studies were performed according to CLSI EP05-A3 and method comparison according to CLSI EP09-A3. Precision studies used a panel of four native and one contrived serum/lithium-heparin plasma samples. One aliquot of each sample pool was tested in duplicate in two runs per day &amp;gt;2 h apart on each analyzer for &amp;gt;20 days with two reagent lots on two systems. For the method comparison, individual native human lithium-heparin plasma samples were analyzed using the Atellica IM TnIH assay on both the Atellica IM and Atellica CI 1900 Analyzers. Detection capability studies including limit of blank (LoB), limit of detection (LoD), and 20-day functional sensitivity (LoQ) were performed according to CLSI EP17-A2 guidelines. Expected values of normal healthy individuals and hook effect were also verified on the Atellica CI 1900 Analyzer. Results Repeatability and within-lab %CVs ranged from 0.7% to 4.4% and 1.3% to 5.1%, respectively, at TnIH concentrations ranging from 13.73 to 23 197.12 ng/L. Method comparison between the Atellica IM TnIH assay on the Atellica CI 1900 Analyzer vs the Atellica IM Analyzer showed a regression slope of 1.00 and an intercept of 0.04 ng/L (n = 170). In detection capability studies, four lots of the Atellica IM TnIH assay on two Atellica CI 1900 analyzers showed a LoB of 0.35 ng/L and an LoD of 0.76 ng/L. LoQ, defined as the lowest amount of analyte in a sample at which within-lab %CV = 20%, was 1.10 ng/L; %CV was approximately 10% at a TNIH concentration of 2.57 ng/L. In addition, &amp;gt;50% of healthy individuals tested had TnIH values &amp;gt;LoD. The 99th percentile for the Atellica IM TnIH assay (45.20 ng/L) was verified on Atellica CI 1900 Analyzer and was consistent with the Atellica IM Analyzer. No interference from biotin was observed up to a concentration of 3500 ng/mL, and no hook effect was observed up to a concentration of 500 000 ng/L. Conclusion Evaluation of the Atellica IM TnIH assay using the Atellica CI 1900 Analyzer demonstrated reproducible assay precision, sensitive detection capabilities, and equivalent performance compared to the same assay on the Atellica IM Analyzer. This evaluation shows that the Atellica IM TnIH assay on Atellica CI 1900 Analyzer meets the definition of a true high-sensitivity troponin I assay as defined by the International Federation of Clinical Chemistry (IFCC) Task Force on Clinical Applications of Cardiac Biomarkers. *The products/features mentioned here are not commercially available in all countries. Their future availability cannot be guaranteed.

Estimation of mean erythrocyte age using HbA1c or HbA1c/glycated albumin for evaluation of anemia severity.

Hemoglobin A1c (HbA1c) levels are low in patients with hemolytic anemia, as HbA1c reflects mean erythrocyte age (MRBC ). Erythrocyte creatine (EC) is a hemolytic indicator that also reflects MRBC . We previously reported an equation for estimating MRBC using EC (EC-MRBC ). In this study, EC-MRBC was compared to the HbA1c level expressed in the International Federation of Clinical Chemistry and Laboratory Medicine units (iA1c) and to the iA1c/glycated albumin (GA) ratio to estimate MRBC . This study included 238 subjects, including patients with hemolytic anemia and/or type 2 diabetes mellitus (T2DM). In non-diabetic individuals, both iA1c and iA1c/GA showed a strong positive correlation with EC-MRBC (p < 0.0001). The equations to estimate iA1c-MRBC and iA1c/GA-MRBC derived from the regression equations between EC-MRBC and iA1c, and EC-MRBC and iA1c/GA in nondiabetic individuals were 1.45 × iA1c and 20.0 × iA1c/GA, respectively. iA1c-MRBC and iA1c/GA-MRBC in non-diabetic individuals without hemolytic anemia were 57.6 ± 4.0 and 57.1 ± 6.4 days, respectively, and iA1c/GA-MRBC in T2DM patients without hemolytic anemia was 56.0 ± 8.8 days.; no significant difference was seen in the comparisons. The MRBC can be estimated using iA1c or iA1c/GA in non-diabetic individuals, and iA1c/GA in T2DM patients.

Comprehensive Comparison of the Capacity of Functionalized Sepharose, Magnetic Core, and Polystyrene Nanoparticles to Immuno-Precipitate Procalcitonin from Human Material for the Subsequent Quantification by LC-MS/MS

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. The fast and accurate diagnosis of sepsis by procalcitonin (PCT) has emerged as an essential tool in clinical medicine. Although in use in the clinical laboratory for a long time, PCT quantification has not yet been standardized. The International Federation of Clinical Chemistry working group on the standardization of PCT (IFCC-WG PCT) aims to provide an LC-MS/MS-based reference method as well as the highest metrological order reference material to address this diagnostic need. Here, we present the systematic evaluation of the efficiency of an immuno-enrichment method, based on functionalized Sepharose, magnetic-core, or polystyrene (latex) nano-particles, to quantitatively precipitate PCT from different human sample materials. This method may be utilized for both mass spectrometric and proteomic purposes. In summary, only magnetic-core nano-particles functionalized by polyclonal PCT antibodies can fulfil the necessary requirements of the international standardization of PCT. An optimized method proved significant benefits in quantitative and specific precipitation as well as in the subsequent LC-MS/MS detection of PCT in human serum samples or HeLa cell extract. Based on this finding, further attempts of the PCT standardization process will utilize a magnetic core-derived immuno-enrichment step, combined with subsequent quantitative LC-MS/MS detection.

Quality standards and internal quality control practices in medical laboratories: an IFCC global survey of member societies.

The trueness and precision of clinical laboratory results are ensured through total quality management systems (TQM), which primarily include internal quality control (IQC) practices. However, quality practices vary globally. To understand the current global state of IQC practice and IQC management in relation to TQM the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on Global Laboratory Quality (TF-GLQ) conducted a survey of IFCC member countries on IQC practices and management. The survey included 16 questions regarding IQC and laboratory TQM practices and was distributed to IFCC full and affiliate member countries (n=110). A total of 46 (41.8 %) responses were received from all regions except North America. Of the responding countries, 78.3 % (n=36) had legislative regulations or accreditation requirements governing medical laboratory quality standards. However, implementation was not mandatory in 46.7 % (n=21) of responding countries. IQC practices varied considerably with 57.1 % (n=28) of respondents indicating that they run 2 levels of IQC, 66.7 % (n=24) indicating they run IQC every 24 h and 66.7 % (n=28) using assay manufacturer IQC material sources. Only 29.3 % (n=12) of respondents indicated that every medical laboratory in their country has written IQC policies and procedures. By contrast, 97.6 % (n=40) of responding countries indicated they take corrective action and result remediation in the event of IQC failure. The variability in TQM and IQC practices highlights the need for more formal programs and education to standardize and improve TQM in medical laboratories.

Point-of-care testing performed by healthcare professionals outside the hospital setting: consensus based recommendations from the IFCC Committee on Point-of-Care Testing (IFCC C-POCT).

The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Committee on Point-of-Care Testing (C-POCT) supports the use of point-of-care testing (POCT) outside of the hospital setting performed by healthcare professionals without formal laboratory education because of its numerous benefits. However, these benefits are associated with risks that must be managed, to ensure the provision of reliable test results and minimize harm to the patient. Healthcare professionals, local regulatory bodies, accredited laboratories as well as manufacturers should actively be engaged in education, oversight and advice to ensure that the healthcare professional selects the appropriate equipment and is able to analyze, troubleshoot and correctly interpret the point-of-care (POC) test results.

Results from an IFCC global survey on laboratory practices for the analysis of circulating tumor DNA

BackgroundThe clinical validity of ctDNA analysis as a diagnostic, prognostic and predictive biomarker has been demonstrated in many studies. The rapid spread of tests for the analysis of ctDNA raises questions regarding their standardization and quality assurance. The aim of this study was to provide a global overview of the test methods, laboratory procedures and quality assessment practices using ctDNA diagnostics. MethodsThe Molecular Diagnostics Committee of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC C-MD) conducted a survey among international laboratories performing ctDNA analysis. Questions on analytical techniques, test parameters, quality assurance and the reporting of findings were included. ResultsA total of 58 laboratories participated in the survey. The majority of the participating laboratories (87.7 %) performed testing for patient care. Most laboratories conducted their assays for lung cancer (71.9 %), followed by colorectal (52.6 %) and breast (40.4 %) cancer, and 55.4 % of the labs used ctDNA analysis for follow-up/monitoring of treatment-resistant alterations. The most frequent gene analysed was EGFR (75.8 %), followed by KRAS (65.5 %) and BRAF (56.9 %). Participation in external quality assessment programs was reported by only 45.6 % of laboratories. ConclusionsThe survey indicates that molecular diagnostic methods for the analysis of ctDNA are not standardized across countries and laboratories. Furthermore, it reveals a number of differences regarding sample preparation, processing and reporting test results. Our findings indicate that ctDNA testing is being conducted without sufficient attention to analytical performance between laboratories and highlights the need for standarisation of ctDNA analysis and reporting in patient care.

Identifying elevated plasma free triiodothyronine levels: age-adapted reference intervals for pediatrics.

Elevated free T3 (FT3) is an important feature for the early diagnosis of several diseases among which Grave's disease or Allan-Hernon-Dudley syndrome. However, there is a lack of age-adapted reference intervals for plasma thyroid hormones in children. We conducted a study to define reference values of peripheral FT3 in children using a commonly used automated immunoassay. All thyroid function test (TFT) results from our lab collected during 9 months were extracted anonymously, and reference intervals establishment followed recommendations validated by International Federation of Clinical Chemistry (IFCC). We defined five reference intervals covering the whole pediatric period. Overall, 26.1% of peripheral FT3 measured in children with normal TSH are out of the adult reference range, and 22.2% are upper it leading to misinterpretation. In a 9-month old patient with severe neurodevelopmental disorders, a pathological elevated FT3 has been securely interpreted using the newly established interval. The study highlights the poor relevance of adult intervals in pediatric cares, as it confirms that plasmatic FT3 is higher during the whole pediatric period. This work reports useful age-adapted reference intervals for free T3 in pediatrics using a widely used electrochemiluminescent Immunoassay (ECLIA) kit.

Reference intervals for cd, hg, Mn and Pb in the general children population (3–14 years) of Kinshasa, Democratic Republic of Congo (DRC) between June 2019 and June 2020

The reference intervals (RIs), proposed by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and the International Union of Pure and Applied Chemistry (IUPAC), were derived for Cd, Hg, Mn and Pb in the blood and urine of the children population living in Kinshasa (n = 200, aged 3–14 years with 97 girls). Levels of metals were measured using coupled plasma mass (ICP-MS). In blood, the proposed RIs [P5-P95 (GM)] were 0.022–1.112 μg/L (0.074), 35.69–144.50 μg/L (71.43), 0.060 to 1.161 μg/L (0.208) and 6.597–15.740 μg/L (9.882) for Cd, Pb, Hg and Mn, respectively. Urinary levels [(P5-P95 (GM)] were 0.082–1.530 μg/L (0.366) for Cd, 1.827–18.500 μg/L (5.458) for Pb, 0.323–1.953 μg/L (0.709) for Hg and 0.070 to 1.703 μg/L (0.186) for Mn. As compared to the CDC updated blood Pb reference value (35 μg/L), Pb levels remain higher of public health concern. Cd and Mn levels were similar to those found in the same city in 2015 and databases involving non-occupationally exposed populations from other countries. Hg levels significantly lower than those found in the same city in 2015, probably due to exclusion criteria of metal exposure applying in the present survey (occupationally exposed to the studied metals, smoking habits, amalgam tooth fillings, fish consumption habit more than one time per week, etc.). These background metal exposures will be useful for future occupational and/or environmental surveys as well as undertaking a reliable regulation of chemical exposure in Kinshasa via a national HBM program.

External quality assessment practices in medical laboratories: an IFCC global survey of member societies.

Clinical laboratory results are required for critical medical decisions, underscoring the importance of quality results. As part of total quality management, external quality assessment (EQA) is a vital component to ensure laboratory accuracy. The goal of this survey was to evaluate the current status of global laboratory quality systems and assess the need for implementation, expansion, or harmonization of EQA programs (EQAP) for Clinical Chemistry and Laboratory Medicine. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on Global Laboratory Quality (TF-GLQ) conducted a survey of IFCC full and affiliate members (n=110) on laboratory quality practice. A total of 41 (37.3%) countries representing all IFCC regions except North America provided responses about EQA availability and practices. All 41 countries perform EQA, 38 reported that their laboratories had EQA policies and procedures, and 39 further act/evaluate unacceptable EQA results. 39 countries indicated they have international and/or national EQAP and 30 use alternative performance assessments. EQA frequency varied among countries. Generally, an EQAP provided the EQA materials (40/41) with four countries indicating that they did not have an EQAP in their country. Globally, most laboratories participate in an EQAP and have defined quality procedures for EQA. There remain gaps in EQA material availability and implementation of EQA as a part of a total laboratory quality system. This survey highlights the need for education, training, and harmonization and will guide efforts of the IFCC TF-GLQ in identifying areas for enhancing global laboratory quality practices.