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In France, sickle cell disease newborn screening (SCD NBS) has been targeted to at-risk regions since 1984, but generalization to the whole population will be implemented from November 2024. Although tandem mass spectrometry (MS/MS) is already used for the NBS of several inherited metabolic diseases, its application for SCD NBS has not been widely adopted worldwide. The aim of this study was to evaluate a dedicated MS/MS kit (Targeted MS/MS Hemo, ZenTech, LaCAR Company, Liege, Belgium) for SCD NBS and to compare the results obtained with those from an NBS reference center using matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) and cation-exchange high-performance liquid chromatography (CE-HPLC, Variant NBS, Biorad Laboratories, Inc., Hercules, CA, USA) as confirmatory method. The MS/MS Hemo kit was used according to the manufacturer's instructions and performed on a Waters Xevo TQ-D (Waters Corporation, USA). The software provided by the manufacturer was used for the calculation and analysis of peptide signal ratios. Among the 1333 samples, the results of 1324 samples were consistent with the HPLC and/or MALDI-TOF results (1263 FA, 50 FAS, 7 FAC, 1 FAO-Arab, and 3 FS). All the discordant results (one FAS on MS/MS vs. FA in CE-HPLC, one FA on MS/MS vs. FAS in CE-HPLC, seven FS on MS/MS vs. FAS in CE-HPLC) were corrected after modifying the peptide signal ratios thresholds, allowing the MS/MS Hemo kit to achieve near-100% sensitivity and specificity for SCD NBS. In conclusion, the MS/MS Hemo kit appears to be an effective method for SCD NBS, particularly for laboratories already equipped with MS/MS technology. However, these results should be confirmed in a larger cohort including a greater number of positive samples for SCD.

Neonatal screening for sickle cell disease (SCD) in France, targeted since 1995, indirectly detects newborns with sickle cell trait (SCT). Information about carrier status must be communicated to families in accordance with the 2006 National Consultative Ethics Committee recommendations; however, no national protocol for this exists. In the departments of Nord and Pas-de-Calais, the Regional Neonatal Screening Center transmits this information through a general practitioner (GP). This study aimed to assess the success rate of local practices in transmitting SCT information to parents. The secondary objectives included explaining transmission failures, evaluating post-information couple screening rates, and conducting a nationwide evaluation of SCT information dissemination. In this retrospective, multicenter study, family doctors were surveyed regarding newborns screened for SCT between January 1 and December 31, 2020, in the Nord and Pas-de-Calais departments. Among the 260 screened newborns, 197 were eligible for analysis. Results showed that 31.2% of newborns with SCT had their GP definitively sharing information with their parents. Based on this information, subsequent parental screening accounted for 13.6% of cases. The reasons cited by the GP for failing to convey information included elusive families (52.5%), unfamiliarity or refusal of the role (35%), limited SCD knowledge (25%), and ethical considerations (12.5%). This study highlights the difficulty and heterogeneity in transmitting carrier status information to parents of newborns with SCT. Our findings could serve as a foundation for the development of new methods for information transmission, given the generalization of neonatal screening for SCD by the French National Authority for Health., (© 2024 The Author(s). Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Newborn screening is a major public health concern. In France, it was established in 1972 with systematic screening for phenylketonuria. Subsequently, other screenings, including congenital hypothyroidism, congenital adrenal hyperplasia, cystic fibrosis, and sickle cell disease, were added. The introduction of tandem mass spectrometry in screening laboratories in 2020 enabled the inclusion of eight additional inherited metabolic diseases: aminoacidopathies (tyrosinemia type I, maple syrup urine disease, and homocystinuria), organic acidurias (isovaleric and glutaric type I acidurias), and disorders of fatty acid metabolism (MCADD, long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), and primary carnitine deficiency). We briefly present these newly added diseases, of which public awareness is still incomplete.

Objective: We compare the risk of Down syndrome among five patients carrying a foetus with digynic triploidy and suggest a course of action for these particular serological profiles., Methods: The concentrations of the different markers used are transformed into multiples of the median by using each of the three software types present on the French market which then determine the risk of Down syndrome., Results: For comparable biochemical and ultrasound profiles, the risk of Down syndrome turns out to be vastly different depending on the type of software employed. The relevance of an immediate diagnostic procedure, of a cell free DNA test or of a basic ultrasound follow-up then arises, leading to a potentially variable care pathway for the patient., Conclusions: This study confirms that for this type of biochemical profile, the laboratory's advisory service is fundamental, that a control ultrasound is essential and that an invasive procedure must be used almost invariably due to the extremely substantial risk factors., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

Screening for fetal Down's syndrome has the peculiarity of combining the biochemical assay of 2 or 3 serum markers with the risk associated with maternal age. If the accuracy of measurement of each parameter is known by the biologist, the uncertainty of the ultimate risk to the patient is not. Indeed, the means of risk calculation involve numerous multi-parameter equations which are not practical for daily use. Defining a re-test limit on thresholds of 1/50 and 1/1,000 is therefore impossible. Since the use of an arbitrarily defined threshold is not being satisfactory, we propose, by default, a methodology based on the exploitation of patient files in the laboratory with risks close to the two decision thresholds. Modulations of the concentrations of all the markers according to their uncertainty allow new risks to be obtained, which can be averaged and framed by an interval of several standard deviations. Choosing the level of uncertainty, the number of files to include, the number of standard deviations framing the average risk, as well as the calculation software, are all choices available to the biologist. The proposed methodology is therefore highly empirical but open, and adaptable, to the specific environment and performance capabilities of each and every laboratory involved.

Previous research has shown that a MALDI-MS technique can be used to screen for sickle cell disease (SCD), and that a system combining automated sample preparation, MALDI-MS analysis and classification software is a relevant approach for first-line, high-throughput SCD screening. In order to achieve a high-throughput "plug and play" approach while detecting "non-standard" profiles that might prompt the misclassification of a sample, we have incorporated various sets of alerts into the decision support software. These included "biological alert" indicators of a newborn's clinical status (e. g., detecting samples with no or low HbA), and "technical alerts" indicators for the most common non-standard profiles, i.e., those which might otherwise lead to sample misclassification. We evaluated these alerts by applying them to two datasets (produced by different laboratories). Despite the random generation of abnormal spectra by one-off technical faults or due to the nature and quality of the samples, the use of alerts fully secured the process of automatic sample classification. Firstly, cases of β-thalassemia were detected. Secondly, after a visual check on the tagged profiles and reanalysis of the corresponding biological samples, all the samples were correctly reclassified without prompting further alerts. All of the samples for which the results were not tagged were well classified (i.e., sensitivity and specificity = 1). The alerts were mainly designed for detecting false-negative classifications; all the FAS samples misclassified by the software as FA (a false negative) were marked with an alert. The implementation of alerts in the NeoScreening ® Laboratory Information Management System's decision support software opens up perspectives for the safe, reliable, automated classification of samples, with a visual check solely on abnormal results or samples. It should now be possible to evaluate the combination of the NeoSickle ® analytical solution and the NeoScreening ® Laboratory Information Management System in a real-life, prospective study of first-line SCD screening., Competing Interests: Conflicts of InterestThe authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results., (© 2019 by the authors.)

The reference methods used for sickle cell disease (SCD) screening usually include two analytical steps: a first tier for differentiating haemoglobin S (HbS) heterozygotes, HbS homozygotes and β-thalassemia from other samples, and a confirmatory second tier. Here, we evaluated a first-tier approach based on a fully automated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) platform with automated sample processing, a laboratory information management system and NeoSickle ® software for automatic data interpretation. A total of 6701 samples (with high proportions of phenotypes homozygous (FS) or heterozygous (FAS) for the inherited genes for sickle haemoglobin and samples from premature newborns) were screened. The NeoSickle ® software correctly classified 98.8% of the samples. This specific blood sample collection was enriched in qualified difficult samples (premature newborns, FAS samples, late and very late samples, etc.). In this study, the sensitivity of FS sample detection was found to be 100% on the Lille MS facility and 99% on the Dijon MS facility, and the specificity of FS sample detection was found to be 100% on both MS facilities. The MALDI-MS platform appears to be a robust solution for first-tier use to detect the HbS variant: it is reproducible and sensitive, it has the power to analyze 600-1000 samples per day and it can reduce the unit cost of testing thanks to maximal automation, minimal intervention by the medical team and good overall practicability. The MALDI-MS approach meets today's criteria for the large-scale, cost-effective screening of newborns, children and adults., Competing Interests: Conflicts of InterestPatrick Ducoroy was an employee of the University of Burgundy at the time of the research described here. He then founded the company Biomaneo, and currently serves as its CEO., (© 2019 by the authors.)

After a short description of the structure and the physiological roles of unconjugated estriol, this paper points out pre-analytical conditions and performances of the serum unconjugated estriol immunoassay, essentially used for Down syndrome screening.

The paper describes the development of an inductively coupled plasma mass spectrometry (ICP MS) method for multitrace element determination in dried blood spots (DBSs). The analytical conditions were optimized using Seronorm™ L-3 and L-1 Certified Reference Materials. The best results were obtained by sampling blood drops on a decontaminated PVDF filter membrane. After drying under metal-free conditions, the DBSs underwent acidic digestion and were analyzed with ICP MS. The method was then validated for As, Cd, Cu, Pb, Mo, Se and Zn. Using a matrix-matched calibration curve, the recovery levels ranged from 96% to 117%. The repeatability and reproducibility were generally below 15%. Limits of quantification ranging from 0.5 to 50 μg/L. In order to investigate the analytical procedure under real sampling conditions, the results obtained from DBSs and liquid blood aliquots (less subject to contamination) from two adult subjects were compared., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Purpose: Universal newborn screening for sickle cell diseases (SCDs) is not currently performed in many countries concerned by this public health problem. Owing to the technical and financial limitations of standard profiling methods (IEF coupled to subsequent HPLC), ethnically targeted neonatal screening is often preferred. Here, we demonstrate that MALDI-MS-based SCD newborn screening could be considered as a potential method for a strategy to universal screening because of its high throughput, cost-effectiveness, sensitivity and ability to automatically discriminate sickle haemoglobin., Experimental Design: We carried out a retrospective study of dried blood spots from 844 Guthrie cards. Four determinations of 1000 mass spectra were performed from each tested dried blood spot., Results: The MALDI-MS-based screening was highly correlated with the reference method. Only 2.3% of the samples presented a poor spectral quality., Conclusions and Clinical Relevance: Given that the overall acquisition, data reprocessing and software-assisted classification (ClinProTools™) time for processing four mass determinations (corresponding to one sample) was around 1 min, 1000 samples can be analysed per day. Rather than seeking to detect as many different haemoglobinopathies as possible, it would become possible to use MALDI-TOF-MS to screen (at a constant cost) as many samples as possible for sickle cell disease., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Most screening programs for sickle cell disease (SCD) utilize isoelectric focusing (IEF) or high performance liquid chromatography (HPLC) to detect haemoglobin (Hb) variants. The first method is not automated and becomes too tedious when many samples have to be investigated. The aim of this work is to explore the capacity of an automated capillary electrophoresis (CE) system, with full traceability, as a tool for newborn screening of SCD., Methods: The Capillarys neonat fast automated system has been developed by Sebia for newborn screening. We performed separate studies using different types of samples to evaluate the utility of the Capillarys for (i) separating Hb S and other variants, and (ii) for performing the routine activity of our laboratory for 20 working days., Results: A throughput of 48 samples per hour with a loading capacity of 192 samples was achieved. Migration times of the major Hb variants were distinct. There were few variants showing similar migration times to Hb S and Hb C and thalassaemia could be detected. In addition, late screening, screening of premature or transfused babies and screening performed using poor quality Guthrie's cards did not interfere with reporting of accurate phenotypes., Conclusions: Sebia Capillarys neonat fast automated system is a reliable tool for haemoglobinopathy neonatal screening.

A comparison was made between the conjugate of national production made by "Carlos J. Finlay" Enterprise of Biological Products for diagnosing rabies by direct immunofluorescence and the viral antinucleocapsid conjugate manufactured by BIORAD that is commercialized at the international level. 150 samples of brain from different animal species were studied at the Rabies Reference Laboratory of "Pedro Kouri" Institute of Tropical Medicine from 2000 to 2002. On comparing both conjugates, there were obtained sensibility, specificity and concordance values of 100%, 94.3% and 98%, respectively. The discordant results were analyzed by the polymerase chain reaction and the biological test in mice.

Mitochondrial acetoacetyl-CoA thiolase (T2) deficiency is an inborn error of metabolism that affects the catabolism of isoleucine and ketone bodies. This disorder is characterized by intermittent ketoacidotic episodes. Recently, we diagnosed T2 deficiency in two patients (GK45 and GK47) by the absence of potassium ion-activated acetoacetyl-CoA thiolase activity, whereas these patients were previously misinterpreted as normal by a coupled assay with tiglyl-CoA as a substrate. This method has been widely used for the enzymatic diagnosis of the T2 deficiency in the United States and Europe. We hypothesized that some residual T2 activity showed normal results in the assay. To prove this hypothesis, we analyzed these two patients together with three typical T2-deficient patients (GK46, GK49, and GK50) at the DNA level. Expression analysis of mutant cDNAs clearly showed that GK45 and GK47 had "mild" mutations (A132G, D339-V340insD) that retained some residual T2 activity, at least one of two mutant alleles, whereas the other three patients had null mutations (c.52-53insC, G152A, H397D, and IVS8+1g>t) in either allele. These results raise the possibility that T2-deficient patients with mild mutations have been misinterpreted as normal by the coupled assay with tiglyl-CoA.

Objective: To establish the frequency of very low maternal serum AFP and to differentiate congenital AFP deficiency from those diseases known to be associated with low AFP., Methods: AFP values below 2 microg/L and borderline values up to 3 microg/L were retrospectively analysed in 839 773 singleton pregnancies included in a programme for routine screening of trisomy 21 maternal serum markers., Results: Serum AFP was undetectable (< or =2 microg/L) in 8 cases, giving a frequency of 1/105 000. The calculated risk of Down syndrome was > or =1/250 in 5 cases. Fetal karyotype was normal. Seven of these pregnancies went to term (39-41 weeks) uneventfully, and birth weight was normal (3050-4110 g). In the 8th case, fetal death occurred at 35 weeks due to severe maternal diabetes. AFP levels between 2.1 and 3.0 microg/L were noted in 7 other cases. The calculated risk of Down syndrome was > or =1/250 in 5 cases, and fetal karyotype was normal. Pregnancies went to term in 4 cases (33-41 weeks), and birth weight was normal (3000-3380 g). In 3 cases, low hCG (<0.6 MoM) was associated with low AFP, and fetal death occurred at 15 to 16 weeks., Conclusion: Once technical errors have been excluded (repeat assay in a second run, calcium assayed to exclude the interference of EDTA for fluorimetric methods, dilution to exclude interfering antibodies, running on an alternative analyser, checking a second sample), very low second-trimester maternal serum AFP should prompt ultrasound examination in order to check fetal viability. Congenital AFP deficiency, an extremely rare disorder (1/100 000), should be suspected. It has no consequences for fetal and infant development, and parents should be reassured., (Copyright 2003 John Wiley & Sons, Ltd.)

In spite of the fact that pouchitis is the most frequently occurring and troublesome complication found in patients treated by ileo-anal anastomosis for ulcerative colitis, no biological marker currently exists to monitor the outcome of the disease. Since it has been noted faecal butyrate is reduced in patients with pouchitis, we developed a simple gas chromatography method to quantify butyrate in faecal water. This test is based on diethyl ether extraction with the use of methacrylic acid as an internal standard. We demonstrated that butyrate was effectively measured when this technique was applied to eleven patients with ileal-pouch anal anastomosis within the first year after the closure of their ileostomy. We also observed a noticeable reduction in the concentration of butyrate in patients who went on to develop a pouchitis.

Urinary trans,trans-muconic acid is a sensitive biomarker for low level benzene exposure. The method described by Ducos et al. (Int Arch Occup Environ Health 1990; 62:529-34) is commonly used for its determination. In this study, we demonstrate that N-benzoyl, L-glutamic acid added to urine samples is a suitable internal standard to control trans,trans-muconic acid recovery after solid phase extraction of urine and to compensate for variations which might occur during high-performance liquid chromatography analysis.