Defining a roadmap for harmonizing quality indicators in Laboratory Medicine: A consensus statement on behalf of the IFCC Working Group "laboratory Error and Patient Safety" and EFLM Task and Finish Group "performance specifications for the extra-analytical phases"

The improving quality of laboratory testing requires a deep understanding of the many vulnerable steps involved in the total examination process (TEP), along with the identification of a hierarchy of risks and challenges that need to be addressed. From this perspective, the Working Group \u201cLaboratory Errors and Patient Safety\u201d (WG-LEPS) of International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) is focusing its activity on implementation of an efficient tool for obtaining meaningful information on the risk of errors developing throughout the TEP, and for establishing reliable information about error frequencies and their distribution. More recently, the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) has created the Task and Finish Group \u201cPerformance specifications for the extraanalytical phases\u201d (TFG-PSEP) for defining performance specifications for extra-analytical phases. Both the IFCC and EFLM groups are working to provide laboratories with a system to evaluate their performances and recognize the critical aspects where improvement actions are needed. A Consensus Conference was organized in Padova, Italy, in 2016 in order to bring together all the experts and interested parties to achieve a consensus for effective harmonization of quality indicators (QIs). A general agreement was achieved and the main outcomes have been the release of a new version of model of quality indicators (MQI), the approval of a criterion for establishing performance specifications and the definition of the type of information that should be provided within the report to the clinical laboratories participating to the QIs project

Diagnostic value of N-terminal ProB-Type Natriuretic Peptide in Emergency Department: Analysis by subgroups

Objectives. Our aim was to evaluate the diagnostic impact of N-terminal pro B-type natriuretic peptide (NT-proBNP) measurement in patients presenting with acute dyspnea in Emergency Department (ED), taking into account clinical and chest x-ray results routinely obtained. Methods. This was a prospective observational study. Four hundred eighty-eight consecutive subjects evaluated for dyspnea in a metropolitan 600 beds hospital ED, entered into the final data analysis. According to a clinical and radiological score, the patients enrolled were divided in three groups: low (A-group), intermediate (B-group), and high (C-group) probability of heart failure. Results. NT-proBNP median value was 2445 ng/L (Inter Quartile Range 631-5847 ng/L), and the area under the receiver-operating characteristic curves (AUC) was 0.854 for NT-proBNP, 0.921 for clinical/radiological score and 0.936 for the two in combination (logistic model). In the B-group (intermediate) NT-proBNP test added correct diagnostic information in 126 subjects with HF and in 53 subjects without a final diagnosis of HF. In A- and C-group NT-proBNP test added correct diagnostic information in 1 patient. Conclusions. NT-proBNP did not substantially enhance diagnostic accuracy in all patients with shortness of breath in ED. However, in patients with not conclusive clinical and radiological results NT-proBNP determinations improved the percentage of correct diagnosis

Multiple micronutrients and docosahexaenoic acid supplementation during pregnancy : A randomized controlled study

Maternal dietary intake during pregnancy needs to meet increased nutritional demands to maintain metabolism and to support fetal development. Docosahexaenoic acid (DHA) is essential for fetal neuro-/visual development and in immunomodulation, accumulating rapidly within the developing brain and central nervous system. Levels available to the fetus are governed by the maternal diet. In this multicenter, parallel, randomized controlled trial, we evaluated once-daily supplementation with multiple micronutrients and DHA (i.e., multiple micronutrient supplementation, MMS) on maternal biomarkers and infant anthropometric parameters during the second and third trimesters of pregnancy compared with no supplementation. Primary efficacy endpoint: change in maternal red blood cell (RBC) DHA (wt% total fatty acids) during the study. Secondary variables: other biomarkers of fatty acid and oxidative status, vitamin D, and infant anthropometric parameters at delivery. Supplementation significantly increased RBC DHA levels, the omega-3 index, and vitamin D levels. Subscapular skinfold thickness was significantly greater with MMS in infants. Safety outcomes were comparable between groups. This first randomized controlled trial of supplementation with multiple micronutrients and DHA in pregnant women indicated that MMS significantly improved maternal DHA and vitamin D status in an industrialized setting\u2014an important finding considering the essential roles of DHA and vitamin D

Clinical, molecular and glycophenotype insights in SLC39A8-CDG

Background: SLC39A8, a gene located on chromosome 4q24, encodes for the manganese (Mn) transporter ZIP8 and its detrimental variants cause a type 2 congenital disorder of glycosylation (CDG). The common SLC39A8 missense variant A391T is associated with increased risk for multiple neurological and systemic disorders and with decreased serum Mn. Patients with SLC39A8-CDG present with different clinical and neuroradiological features linked to variable transferrin glycosylation profile. Galactose and Mn supplementation therapy results in the biochemical and clinical amelioration of treated patients. Results: Here, we report clinical manifestations, neuroradiological features and glycophenotypes associated with novel SLC39A8 variants (c.1048G > A; p.Gly350Arg and c.131C > G; p.Ser44Trp) in two siblings of the same Italian family. Furthermore, we describe a third patient with overlapping clinical features harbouring the homozygous missense variant A391T. The clinical phenotype of the three patients was characterized by severe developmental disability, dystonic postural pattern and dyskinesia with a more severe progression of the disease in the two affected siblings. Neuroimaging showed a Leigh syndrome-like pattern involving the basal ganglia, thalami and white matter. In the two siblings, atrophic cerebral and cerebellum changes consistent with SLC39A8-CDG were detected as well. Serum transferrin isoelectric focusing (IEF) yielded variable results with slight increase of trisialotransferrin isoforms or even normal pattern. MALDI-MS showed the presence of hypogalactosylated transferrin N-glycans, spontaneously decreasing during the disease course, only in one affected sibling. Total serum N-glycome depicted a distinct pattern for the three patients, with increased levels of undergalactosylated and undersialylated precursors of fully sialylated biantennary glycans, including the monosialo-monogalacto-biantennary species A2G1S1. Conclusions: Clinical, MRI and glycosylation features of patients are consistent with SLC39A8-CDG. We document two novel variants associated with Leigh syndrome-like disease presentation of SLC39A8-CDG. We show, for the first time, a severe neurological phenotype overlapping with that described for SLC39A8-CDG in association with the homozygous A391T missense variant. We observed a spontaneous amelioration of transferrin N-glycome, highlighting the efficacy of MS-based serum glycomics as auxiliary tool for the diagnosis and clinical management of therapy response in patients with SLC39A8-CDG. Further studies are needed to analyse more in depth the influence of SLC39A8 variants, including the common missense variant, on the expression and function of ZIP8 protein, and their impact on clinical, biochemical and neuroradiological features

Frequency and phenotypic spectrum of KMT2B dystonia in childhood: A single‐center cohort study

Background: Childhood-onset dystonia is often genetically determined. Recently, KMT2B variants have been recognized as an important cause of childhood-onset dystonia. Objective: To define the frequency of KMT2B mutations in a cohort of dystonic patients aged less than 18 years at onset, the associated clinical and radiological phenotype, and the natural history of disease. Methods: Whole-exome sequencing or customized gene panels were used to screen a cohort of sixty-five patients who had previously tested negative for all other known dystonia-associated genes. Results: We identified fourteen patients (21.5%) carrying KMT2B variants, of which one was classified as a Variant of Unknown Significance (VUS). We also identified two additional patients carrying pathogenic mutations in GNAO1 and ATM. Overall, we established a definitive genetic diagnosis in 23% of cases. We observed a spectrum of clinical manifestations in KMT2B variant carriers, ranging from generalized dystonia to short stature or intellectual disability alone, even within the same family. In 78.5% of cases, dystonia involved the lower limbs at onset, with later caudo-cranial generalization. Eight patients underwent pallidal Deep Brain Stimulation with a median decrease of BFMDRS-M score of 38.5% in the long term. We also report four asymptomatic carriers, suggesting that some KMT2B mutations may be associated with incomplete disease penetrance. Conclusions: KMT2B mutations are frequent in childhood-onset dystonia and cause a complex neurodevelopmental syndrome often featuring growth retardation and intellectual disability as additional phenotypic features. A dramatic and long-lasting response to Deep Brain Stimulation is characteristic of DYT-KMT2B dystonia

IFCC Working Group Recommendations for Assessing Commutability Part 3 : Using the Calibration Effectiveness of a Reference Material

A process is described to assess the commutability of a reference material (RM) intended for use as a calibrator based on its ability to fulfill its intended use in a calibration traceability scheme to produce equivalent clinical sample (CS) results among different measurement procedures (MPs) for the same measurand. Three sources of systematic error are elucidated in the context of creating the calibration model for translating MP signals to measurand amounts: calibration fit, calibrator level trueness, and commutability. An example set of 40 CS results from 7 MPs is used to illustrate estimation of bias and variability for each MP. The candidate RM is then used to recalibrate each MP, and its effectiveness in reducing the systematic error among the MPs within an acceptable level of equivalence based on medical requirements confirms its commutability for those MPs. The RM is declared noncommutable for MPs for which, after recalibration, the CS results do not agree with those from other MPs. When a lack of agreement is found, other potential causes, including lack of calibration fit, should be investigated before concluding the RM is noncommutable. The RM is considered fit for purpose for those MPs where commutability is demonstrate