External quality assessment performance in ten countries: an IFCC global laboratory quality project.

Objectives: This study aimed to assess the validity of external quality assessment (EQA) laboratory results across various cultural and environmental contexts and to identify potential improvement areas.

Methods: The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on Global Laboratory Quality (TF-GLQ) conducted a 2-year study (2022 and 2023) in which EQA materials, related software and online training was provided by a commercial vendor to 100 laboratories in ten IFCC member society countries. The results were analysed on a monthly basis by the TF-GLQ, to show the number of submissions per country, tests per lab, acceptability rates, random failures and to get a measure of which analytes performed poorly.

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

Objectives: 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.

Recommendations for the application and follow-up of quality controls in medical laboratories.

This is a translation of the paper "Recommendations for the application and follow-up of quality controls in medical biology laboratories" published in French in the journal Annales de Biologie Clinique (Recommandations pour la mise en place et le suivi des contrôles de qualité dans les laboratoires de biologie médicale. Ann Biol Clin (Paris). 2019;77:577-97.

[Examples of accreditation of serum and urinary proteins electrophoresis].

Serum proteins and urinary proteins electrophoresis are useful biological tests. They are often prescribed for the screening of monoclonal gammopathys and also during follow-up for treatment response. This test can be accredited according to standard NF ISO 15189 since laboratories use analysers and adapted reagents, but there are numerous protocols for the method validation.

[Recommendations for the application and the follow-up of quality controls in medical biology laboratories].

The recommendations that we formulate in this document come from LABAC, SFBC and FAEEQ. They describe the different steps from the initial application of quality controls, based on risk analysis: the changes of reagent batches or internal quality controls (IQC) batches, the course when IQC are not in accordance with references, the choice of external quality evaluation and the interpretation of its results, the comparability of results obtained in several analysers used in the same laboratory. Lastly, measurement uncertainty, robustness of methods and specificities of near-patient biology and rapid tests are described.

Recommendation for the review of biological reference intervals in medical laboratories.

This document is based on the original recommendation of the Expert Panel on the Theory of Reference Values of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), updated guidelines were recently published under the auspices of the IFCC and the Clinical and Laboratory Standards Institute (CLSI). This document summarizes proposals for recommendations on: (i) The terminology, which is often confusing, noticeably concerning the terms of reference limits and decision limits. (ii) The method for the determination of reference limits according to the original procedure and the conditions, which should be used.

L-carnitine treatment in incident hemodialysis patients: the multicenter, randomized, double-blinded, placebo-controlled CARNIDIAL trial.

Background: L-carnitine levels decrease rapidly and steadily with duration of hemodialysis, and carnitine depletion can impair response to recombinant human erythropoietin (rHuEPO). The study hypothesis was that L-carnitine supplementation during the first year of hemodialysis would improve this response.

Design, Setting, Participants, & Measurements: From October 2006 through March 2010, this multicenter, randomized, double-blinded study assigned 92 incident hemodialysis patients to receive placebo or 1 g of intravenous L-carnitine after each dialysis session for 1 year.

[Analytical quality of assays and comparison of procedures for the sweat test].

Sweat test measuring the chloride ion (Cl(-)) concentration in sweat is a tool for the cystic fibrosis (CF) diagnosis. We evaluated analytical criteria of different available methods and compared them into five hospitals and throught a national quality control program. Sweat tests were performed by stimulation using pilocarpine iontophoresis, sweat collection and measurement of sweat Cl(-) (mmol/L) by titration (colorimetric or coulometric end-point) or by in situ direct potentiometry using a chloride-selective electrode.

Successful treatment of severe cardiomyopathy in glycogen storage disease type III With D,L-3-hydroxybutyrate, ketogenic and high-protein diet.

Glycogen storage disease type III (GSD III) due to debranching enzyme deficiency presenting usually with hepatomegaly and hypoglycemia may be responsible for severe cardiomyopathy which is often fatal. Current treatment of GSD III is based on frequent high-carbohydrate meals that have no effect on the cardiomyopathy. We describe a 2-mo-old infant presenting with a familial form of GSD III complicated with cardiomyopathy.

Multiple sources of metabolic disturbance in ETHE1-related ethylmalonic encephalopathy.

Ethylmalonic encephalopathy (EE) is a rare metabolic disorder caused by dysfunction of ETHE1, a mitochondrial dioxygenase involved in hydrogen sulfide (H2S) detoxification. Patients present in infancy with psychomotor retardation, chronic diarrhea, orthostatic acrocyanosis and relapsing petechiae. High levels of lactic acid, ethymalonic acid (EMA) and methylsuccinic acid (MSA) are detected in body fluids.

New SUCLG1 patients expanding the phenotypic spectrum of this rare cause of mild methylmalonic aciduria.

Deficiencies in two subunits of the succinyl-coenzyme A synthetase (SCS) have been involved in patients with encephalomyopathy and mild methylmalonic aciduria (MMA). In this study, we described three new SUCLG1 patients and performed a meta-analysis of the literature. Our report enlarges the phenotypic spectrum of SUCLG1 mutations and confirms that a characteristic metabolic profile (presence of MMA and C4-DC carnitine in urines) and basal ganglia MRI lesions are the hallmarks of SCS defects.

Multicenter evaluation of the hemolysis index in automated clinical chemistry systems.

Background: In vitro hemolysis, the prevailing cause of preanalytical error in routine laboratory diagnostics, might influence the reliability of several tests, affect the quality of the total testing process and jeopardize patient safety. Although laboratory instrumentation is now routinely equipped with systems capable of automatically testing and eventually correcting for hemolysis interference, to our knowledge there are no reports that have compared the efficiency of different analytical platforms for identifying and classifying specimens with hemolysis.

Methods: Serum from a healthy volunteer was spiked with varying amounts of hemolyzed blood from the same volunteer, providing a serum free hemoglobin concentration ranging from 0.

Causes, consequences, detection, and prevention of identification errors in laboratory diagnostics.

Laboratory diagnostics, a pivotal part of clinical decision making, is no safer than other areas of healthcare, with most errors occurring in the manually intensive preanalytical process. Patient misidentification errors are potentially associated with the worst clinical outcome due to the potential for misdiagnosis and inappropriate therapy. While it is misleadingly assumed that identification errors occur at a low frequency in clinical laboratories, misidentification of general laboratory specimens is around 1% and can produce serious harm to patients, when not promptly detected.

Haemolysis: an overview of the leading cause of unsuitable specimens in clinical laboratories.

Prevention of medical errors is a major goal of healthcare, though healthcare workers themselves have not yet fully accepted or implemented reliable models of system error, and neither has the public. While there is widespread perception that most medical errors arise from an inappropriate or delayed clinical management, the issue of laboratory errors is receiving a great deal of attention due to their impact on the quality and efficiency of laboratory performances and patient safety. Haemolytic specimens are a frequent occurrence in clinical laboratories, and prevalence can be as high as 3.

What's new in metabolic and genetic hypoglycaemias: diagnosis and management.

Hypoglycaemia in children can be a life-threatening situation that needs to be assessed rigorously in order to treat efficiently and avoid relapse that can be responsible for cerebral damage. The diagnosis of impairment in glucose homeostasis requires the knowledge of the mechanisms regulating blood glucose concentration. The clinical history and presentation, when available, especially the timing of hypoglycaemia with respect to the last meal and some simple clinical and biological tests may allow diagnosing the vast majority of patients presenting with hypoglycaemia.

Early energy deficit in Huntington disease: identification of a plasma biomarker traceable during disease progression.

Huntington disease (HD) is a fatal neurodegenerative disorder, with no effective treatment. The pathogenic mechanisms underlying HD has not been elucidated, but weight loss, associated with chorea and cognitive decline, is a characteristic feature of the disease that is accessible to investigation. We, therefore, performed a multiparametric study exploring body weight and the mechanisms of its loss in 32 presymptomatic carriers and HD patients in the early stages of the disease, compared to 21 controls.

Muscle-specific loss of apoptosis-inducing factor leads to mitochondrial dysfunction, skeletal muscle atrophy, and dilated cardiomyopathy.

Cardiac and skeletal muscle critically depend on mitochondrial energy metabolism for their normal function. Recently, we showed that apoptosis-inducing factor (AIF), a mitochondrial protein implicated in programmed cell death, plays a role in mitochondrial respiration. However, the in vivo consequences of AIF-regulated mitochondrial respiration resulting from a loss-of-function mutation in Aif are not known.

Heterogeneity of persistent hyperinsulinaemic hypoglycaemia. A series of 175 cases.

Unlabelled: Hyperinsulinism is a heterogeneous disorder characterised by severe hypoglycaemia due to an inappropriate oversecretion of insulin. In a personal series of 175 patients investigated for hyperinsulinaemic hypoglycaemia over the last 20 years, we review clinical presentations, molecular studies and therapeutic management of hyperinsulinism. There were 98 neonatal-onset patients, including 86 permanent hyperinsulinism and 12 transient forms, 68 with infancy-onset and nine with childhood-onset.