scholarly journals QUALITY OF DRIED BLOOD SPOTS IS AN INTEGRAL COMPONENT OF PROMPT DETECTION OF INBORN ERRORS OF METABOLISM

2020 ◽  
Vol 10 (4(38)) ◽  
pp. 77-86
Author(s):  
Tetiana Znamenska ◽  
O. Vorobiova ◽  
I. Kuzneczov ◽  
I. Lastivka ◽  
A. Kremezna ◽  
...  
Keyword(s):  
Newborn Screening ◽  
Inborn Errors Of Metabolism ◽  
Dried Blood Spots ◽  
Poor Quality ◽  
Blood Sampling ◽  
Inborn Errors ◽  
Blood Spots ◽  
Expanded Newborn Screening ◽  
Practical Recommendations

Introduction. Inborn Errors of Metabolism (IEM) are constituted a group of genetic diseases that are associated with defects in the synthesis or catabolism of complex molecules, impaired intermediary metabolism and energy production/utilization processes. The clinical manifestation of IEM is nonspecific, that looks similar to septicemia, and most often occurs in the neonatal period with life-threatening acute metabolic crises. Expanded Newborn Screening (ENS) – a biochemical study of the blood of all newborns without exception with the purpose to identify molecular markers of these diseases proved to be the most effective instrument of early IEM diagnostics. The quality of the biological samples (dried blood spots, DBS) in great extent determines the timing, accuracy, and reliability of the results of biochemical measurements. Obtaining of equivocal results in the case of analysis of poor quality DBS requires repeated laboratory tests, that delays the diagnostic process and postpones the start of specific treatment, which usually results in irreversible damage of the brain and internal organs of the child. The aim of this work is to (i) review the first results of the implementation of Expanded Newborn Screening in Ukraine (pilot part of the Baby Screen Project), and to analyze literature data regarding the negative impact of poor quality DBS on laboratory determination of IEM marker substances contents in the specimens, (ii) to characterize the typical errors in blood sampling and drying of  blood spots, and (iii) to provide practical recommendations for the proper performance of these procedures. Materials and methods. Own data of retrospective analysis of the questionable ENS results was superimposed with dried blood specimens, that were investigated in the Pharmbiotest ENS Lab to outline most common inaccuracies. Based on the comparison of these data with the relevant publications it was formulated the practical recommendations for improving quality of DBS preparation to ensure the accuracy and reliability of laboratory measurements and speed up IEM diagnostics. Results. The quality of biomaterial selection is an important part of obtaining reliable results during expanded newborn screening. Capillary blood is collected in the maternity hospital from 48-72 hours (full-term) and for 7-11 days (in preterm babies) after the birth from the heel of babies. In this case, a few drops of blood are applied to a special test card made of filter paper, which is dried and sent to the laboratory. Blood tests are performed using a highly sensitive and accurate method of chemical analysis - tandem mass spectrometry in the laboratory "Pharmbiotest", located in Ukraine. Taking into analysis the low-quality samples lead to questionable results, which requires repeated DBS sampling and re-examining. This proved to be the most common cause of delaying IEM detection, diagnosis establishment, and initiation of treatment, which can be fatal for a child with severe IEM forms. Conclusions. Informing healthcare professionals and parents about the current results of laboratory monitoring of dried blood spots quality, typical errors in blood sampling and following on-site procedures and negative consequences of its improper performance, as well as providing clear practical recommendations of how these procedures should be done is a proven way of improving and speeding up IEM diagnostics.

scholarly journals Diagnostic potential of stored dried blood spots for inborn errors of metabolism: a metabolic autopsy of medium-chain acyl-CoA dehydrogenase deficiency

2018 ◽  
Vol 71 (10) ◽  
pp. 885-889 ◽  
Author(s):  
Noriyuki Kaku ◽  
Kenji Ihara ◽  
Yuichiro Hirata ◽  
Kenji Yamada ◽  
Sooyoung Lee ◽  
...  
Keyword(s):  
Newborn Screening ◽  
Inborn Errors Of Metabolism ◽  
Dried Blood Spots ◽  
Screening Tests ◽  
Inborn Errors ◽  
Mcad Deficiency ◽  
Medium Chain ◽  
Blood Spots ◽  
Chain Acyl ◽  
Biochemical Analyses

AimIt is estimated that 1–5% of sudden infant death syndrome (SIDS) cases might be caused by undiagnosed inborn errors of metabolism (IEMs); however, the postmortem identification of IEMs remains difficult. This study aimed to evaluate the usefulness of dried blood spots (DBSs) stored after newborn screening tests as a metabolic autopsy to determine the causes of death in infants and children who died suddenly and unexpectedly.MethodsInfants or toddlers who had suddenly died without a definite diagnosis between July 2008 and December 2012 at Kyushu University Hospital in Japan were enrolled in this study. Their Guthrie cards, which had been stored for several years at 4–8°C, were used for an acylcarnitine analysis by tandem mass spectrometry to identify inborn errors of metabolism.ResultsFifteen infants and children who died at less than 2 years of age and for whom the cause of death was unknown were enrolled for the study. After correcting the C0 and C8 values assuming the hydrolysation of acylcarnitine in the stored DBSs, the corrected C8 value of one case just exceeded the cut-off level for medium-chain acyl-CoA dehydrogenase (MCAD) deficiency screening. Genetic and biochemical analyses confirmed this patient to have MCAD deficiency.ConclusionDBSs stored after newborn screening tests are a promising tool for metabolic autopsy. The appropriate compensation of acylcarnitine data and subsequent genetic and biochemical analyses are essential for the postmortem diagnosis of inborn errors of metabolism.

scholarly journals Spectrum analysis of inborn errors of metabolism for expanded newborn screening in a northwestern Chinese population

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ruixue Zhang ◽  
Rong Qiang ◽  
Chengrong Song ◽  
Xiaoping Ma ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Newborn Screening ◽  
Inborn Errors Of Metabolism ◽  
Northwest China ◽  
Methylmalonic Acidemia ◽  
Shaanxi Province ◽  
Inborn Errors ◽  
Organic Acidurias ◽  
Genetic Characteristics ◽  
Disease Spectrum ◽  
Expanded Newborn Screening

AbstractExpanded newborn screening facilitates early identification and intervention of patients with inborn errors of metabolism (IEMs), There is a lack of disease spectrum data for many areas in China. To determine the disease spectrum and genetic characteristics of IEMs in Xi'an city of Shaanxi province in northwest China, 146152 newborns were screening by MSMS from January 2014 to December 2019 and 61 patients were referred to genetic analysis by next generation sequencing (NGS) and validated by Sanger sequencing. Seventy-five newborns and two mothers were diagnosed with IEMs, with an overall incidence of 1:1898 (1:1949 without mothers). There were 35 newborns with amino acidemias (45.45%, 1:4176), 28 newborns with organic acidurias (36.36%, 1:5220), and 12 newborns and two mothers with FAO disorders (18.18%; 1:10439 or 1:12179 without mothers). Phenylketonuria and methylmalonic acidemia were the two most common disorders, accounting for 65.33% (49/75) of all confirmed newborn. Some hotspot mutations were observed for several IEMs, including PAH gene c.728G>A for phenylketonuria; MMACHC gene c.609G>A and c.567dupT, MMUT gene c.323G>A for methylmalonic acidemia and SLC25A13 gene c.852_855del for citrin deficiency. Our study provides effective clinical guidance for the popularization and application of expanded newborn screening, genetic screening, and genetic counseling of IEMs in this region.

The first territory-wide expanded newborn screening for inborn errors of metabolism in Hong Kong: a pilot study

Pathology ◽  
2017 ◽  
Vol 49 ◽  
pp. S98 ◽  
Author(s):  
Ching-wan Lam ◽  
Chun-yiu Law ◽  
Chloe Miu Mak ◽  
Wai-kwan Siu ◽  
Hencher Han-Chih Lee ◽  
...  
Keyword(s):  
Hong Kong ◽  
Pilot Study ◽  
Newborn Screening ◽  
Inborn Errors Of Metabolism ◽  
Inborn Errors ◽  
Expanded Newborn Screening

scholarly journals Performance of Expanded Newborn Screening in Norway Supported by Post-Analytical Bioinformatics Tools and Rapid Second-Tier DNA Analyses

2020 ◽  
Vol 6 (3) ◽  
pp. 51 ◽  
Author(s):  
Trine Tangeraas ◽  
Ingjerd Sæves ◽  
Claus Klingenberg ◽  
Jens Jørgensen ◽  
Erle Kristensen ◽  
...  
Keyword(s):  
Newborn Screening ◽  
Screening Program ◽  
Good Health ◽  
Dried Blood Spots ◽  
Case Definitions ◽  
Inborn Errors ◽  
Disease Spectrum ◽  
Expanded Newborn Screening ◽  
Second Tier ◽  
Biochemical Testing

In 2012, the Norwegian newborn screening program (NBS) was expanded (eNBS) from screening for two diseases to that for 23 diseases (20 inborn errors of metabolism, IEMs) and again in 2018, to include a total of 25 conditions (21 IEMs). Between 1 March 2012 and 29 February 2020, 461,369 newborns were screened for 20 IEMs in addition to phenylketonuria (PKU). Excluding PKU, there were 75 true-positive (TP) (1:6151) and 107 (1:4311) false-positive IEM cases. Twenty-one percent of the TP cases were symptomatic at the time of the NBS results, but in two-thirds, the screening result directed the exact diagnosis. Eighty-two percent of the TP cases had good health outcomes, evaluated in 2020. The yearly positive predictive value was increased from 26% to 54% by the use of the Region 4 Stork post-analytical interpretive tool (R4S)/Collaborative Laboratory Integrated Reports 2.0 (CLIR), second-tier biochemical testing and genetic confirmation using DNA extracted from the original dried blood spots. The incidence of IEMs increased by 46% after eNBS was introduced, predominantly due to the finding of attenuated phenotypes. The next step is defining which newborns would truly benefit from screening at the milder end of the disease spectrum. This will require coordinated international collaboration, including proper case definitions and outcome studies.

Contamination of dried blood spots – an underestimated risk in newborn screening

2018 ◽  
Vol 56 (2) ◽  
pp. 278-284 ◽  
Author(s):  
Theresa Winter ◽  
Anja Lange ◽  
Anke Hannemann ◽  
Matthias Nauck ◽  
Cornelia Müller
Keyword(s):  
Newborn Screening ◽  
Infant Formula ◽  
False Positive ◽  
Dried Blood Spots ◽  
Substantial Effect ◽  
Blood Collection ◽  
Inborn Errors ◽  
Blood Spots ◽  
Filter Papers ◽  
The Impact

Abstract Background: Newborn screening (NBS) is an established screening procedure in many countries worldwide, aiming at the early detection of inborn errors of metabolism. For decades, dried blood spots have been the standard specimen for NBS. The procedure of blood collection is well described and standardized and includes many critical pre-analytical steps. We examined the impact of contamination of some anticipated common substances on NBS results obtained from dry spot samples. This possible pre-analytical source of uncertainty has been poorly examined in the past. Methods: Capillary blood was obtained from 15 adult volunteers and applied to 10 screening filter papers per volunteer. Nine filter papers were contaminated without visible trace. The contaminants were baby diaper rash cream, baby wet wipes, disinfectant, liquid infant formula, liquid infant formula hypoallergenic (HA), ultrasonic gel, breast milk, feces, and urine. The differences between control and contaminated samples were evaluated for 45 NBS quantities. We estimated if the contaminations might lead to false-positive NBS results. Results: Eight of nine investigated contaminants significantly altered NBS analyte concentrations and potentially caused false-positive screening outcomes. A contamination with feces was most influential, affecting 24 of 45 tested analytes followed by liquid infant formula (HA) and urine, affecting 19 and 13 of 45 analytes, respectively. Conclusions: A contamination of filter paper samples can have a substantial effect on the NBS results. Our results underline the importance of good pre-analytical training to make the staff aware of the threat and ensure reliable screening results.

Sign in / Sign up

Export Citation Format

Share Document