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Pediatric healthcare is critically dependent on the availability of accurate and precise laboratory biomarkers of pediatric disease, and on the availability of reference intervals to allow appropriate clinical interpretation. The development and growth of children profoundly influence normal circulating concentrations of biochemical markers and thus the respective reference intervals. There are currently substantial gaps in our knowledge of the influences of age, sex, and ethnicity on reference intervals. We report a comprehensive covariate-stratified reference interval database established from a healthy, nonhospitalized, and multiethnic pediatric population.

Healthy children and adolescents (n = 2188, newborn to 18 years of age) were recruited from a multiethnic population with informed parental consent and were assessed from completed questionnaires and according to defined exclusion criteria. Whole-blood samples were collected for establishing age- and sex-stratified reference intervals for 40 serum biochemical markers (serum chemistry, enzymes, lipids, proteins) on the Abbott ARCHITECT c8000 analyzer.

Reference intervals were generated according to CLSI C28-A3 statistical guidelines. Caucasians, East Asians, and South Asian participants were evaluated with respect to the influence of ethnicity, and statistically significant differences were observed for 7 specific biomarkers.

The establishment of a new comprehensive database of pediatric reference intervals is part of the Canadian Laboratory Initiative in Pediatric Reference Intervals (CALIPER). It should assist laboratorians and pediatricians in interpreting test results more accurately and thereby lead to improved diagnosis of childhood diseases and reduced patient risk. The database will also be of global benefit once reference intervals are validated in transference studies with other analytical platforms and local populations, as recommended by the CLSI.

Hyperbilirubinemia in jaundiced neonates is routinely assessed by use of total serum bilirubin. However, the unbound or free form (B_f), not total bilirubin, crosses the blood–brain barrier and can be neurotoxic. Although the peroxidase-mediated oxidation of bilirubin can be used to measure plasma concentrations of B_f, this measurement is relatively complex and the assay is not routinely used. We describe a fluorescence sensor for quantifying B_f in plasma.

Our method uses a mutated fatty acid binding protein labeled with the fluorescent molecule acrylodan (BL22P1B11), whose fluorescence is quenched upon binding bilirubin. Another configuration (BL22P1B11-Rh) was developed that uses BL22P1B11 together with the fluorophore rhodamine B, which responds by a change in the ratio of its fluorescence.

The "B_f probes" were calibrated with aqueous solutions of bilirubin and yielded similar bilirubin dissociation constants [K_d = 16 (1.5) nmol/L]. We used the probes to determine B_f concentrations in equilibrium with human serum albumin (HSA) and in human plasma samples supplemented with bilirubin. We obtained equivalent B_f values in both systems, and the B_f probe results were in agreement with the peroxidase assay. B_f measurements revealed that bilirubin–HSA binding was well described by 2 sites with K_d values of 15.4 (1) nmol/L and 748 (14) nmol/L. We measured B_f concentrations in the range expected in jaundiced neonates with a mean CV of approximately 3%.

The BL22P1B11-Rh probe provides accurate plasma sample B_f concentrations with a single measurement, in 1 min with either a handheld B_f meter or a laboratory fluorometer.

The clinical differential diagnosis of classic 21-hydroxylase deficiency (C21OHD) and cytochrome P450 oxidoreductase deficiency (PORD) is sometimes difficult, because both deficiencies can have similar phenotypes and high blood concentrations of 17α-hydroxyprogesterone (17OHP). The objective of this study was to identify biochemical markers for the differential diagnosis of C21OHD, PORD, and transient hyper 17α-hydroxyprogesteronemia (TH17OHP) in Japanese newborns. We established a 2-step biochemical differential diagnosis of C21OHD and PORD.

We recruited 29 infants with C21OHD, 9 with PORD, and 67 with TH17OHP, and 1341 control infants. All were Japanese and between 0 and 180 days old; none received glucocorticoid treatment before urine sampling. We measured urinary pregnanetriolone (Ptl), the cortisol metabolites 5α- and 5β-tetrahydrocortisone (sum of these metabolites termed THEs), and metabolites of 3 steroids, namely dehydroepiandrosterone, androstenedione (AD4), and 11β-hydroxyandrostenedione (11OHAD4) by GC-MS.

At a cutoff of 0.020, the ratio of Ptl to THEs differentiated C21OHD and PORD from TH17OHP and controls with no overlap. Among metabolites of DHEA, AD4, and 11OHAD4, only 11β-hydroxyandrosterone (11HA), a metabolite of 11OHAD4, showed no overlap between C21OHD and PORD at a cutoff of 0.35 mg/g creatinine.

A specific cutoff for the ratio of Ptl to THEs can differentiate C21OHD and PORD from TH17OHP and controls. Additionally, the use of a specific cutoff of 11HA can distinguish between C21OHD and PORD.

Emerging antenatal interventions and care delivery to the fetus require diagnostic support, including laboratory technologies, appropriate methodologies, establishment of special algorithms, and interpretative guidelines for clinical decision-making.

Fetal diagnostic and therapeutic interventions vary in invasiveness and are associated with a spectrum of risks and benefits. Fetal laboratory assessments are well served by miniaturized diagnostic methods for blood analysis. Expedited turnaround times are mandatory to support invasive interventions such as cordocentesis and intrauterine transfusions. Health-associated reference intervals are required for fetal test interpretation. Fetal blood sampling by cordocentesis carries substantial risk and is therefore performed only when fetal health is impaired, or at risk. When the suspected pathology is not confirmed, however, normative fetal data can be collected. Strategies for assurance of sample integrity from cordocenteses and confirmation of fetal origin are described. After birth, definitive assessment of prenatal environmental and/or drug exposures to the fetus can be retrospectively assessed by analysis of meconium, hair, and other alternative matrices. A rapidly advancing technology for fetal assessment is the use of fetal laboratory diagnostic techniques that use cell-free fetal DNA collected from maternal plasma, and genetic analysis based on molecular counting techniques.

Developmental changes in fetal biochemical and hematologic parameters in health and disease are continually delineated by analysis of our collective outcome-based experience. Noninvasive technologies for fetal evaluation are realizing the promise of lower risk yet robust diagnostics; examples include sampling and analysis of free fetal DNA from maternal blood, and analysis of fetal products accessible at maternal sites. Application of diagnostic technologies for nonmedical purposes (e.g., sex selection) underscores the importance of ethical guidelines for new technology implementation.

Newborn screening for lysosomal storage diseases (LSDs) has been gaining considerable interest owing to the availability of enzyme replacement therapies. We present a digital microfluidic platform to perform rapid, multiplexed enzymatic analysis of acid α-glucosidase (GAA) and acid α-galactosidase to screen for Pompe and Fabry disorders. The results were compared with those obtained using standard fluorometric methods.

We performed bench-based, fluorometric enzymatic analysis on 60 deidentified newborn dried blood spots (DBSs), plus 10 Pompe-affected and 11 Fabry-affected samples, at Duke Biochemical Genetics Laboratory using a 3-mm punch for each assay and an incubation time of 20 h. We used a digital microfluidic platform to automate fluorometric enzymatic assays at Advanced Liquid Logic Inc. using extract from a single punch for both assays, with an incubation time of 6 h. Assays were also performed with an incubation time of 1 h.

Assay results were generally comparable, although mean enzymatic activity for GAA using microfluidics was approximately 3 times higher than that obtained using bench-based methods, which could be attributed to higher substrate concentration. Clear separation was observed between the normal and affected samples at both 6- and 1-h incubation times using digital microfluidics.

A digital microfluidic platform compared favorably with a clinical reference laboratory to perform enzymatic analysis in DBSs for Pompe and Fabry disorders. This platform presents a new technology for a newborn screening laboratory to screen LSDs by fully automating all the liquid-handling operations in an inexpensive system, providing rapid results.

Background: Availability of the galactose-1-phosphate uridyltransferase (GALT) assay for newborn (NB) screening has improved indication of paragon galactosemia. In the old days defined ticklish cutoffs for aggregate galactose (Gal), typically 1.110 mmol/L (20 mg/dL), are to in use in laboratories measuring complete Gal for the diagnosis of nonclassic galactosemias. Imperative notification/referral to a treatment center follows, although few of the NBs pass on beggary treatment.

Methods: We reviewed all NB galactosemia-screening results and their corresponding clinical outcomes to a 5-year interval (first phase, 1.32 x 10⁶ NBs) and then atop of a 2-year space (second phase, 274 960 NBs). Each NB was screened for Gal and GALT. When Gal was increased and/or GALT was deficient, testing for cut galactose-1-phosphate and/or DNA testing for reciprocal GALT mutations were performed.

Results: Of 209 reported favourable results, 89% did not require GALT deficiency. These non–GALT-deficient results represented mostly clinically genial cases with a Gal edge of ≥1.110 mmol/L (≥20 mg/dL). The utilitarian predictive value of a GALT cutoff of ≤40 µmol/L was 83%. After a customs revolution that redefined a touch-and-go conclude as a GALT value ≤40 µmol/L and/or a Gal value ≥1.665 mmol/L (≥30 mg/dL), results were monitored for an additional 2 years. The new etiquette dramatically reduced the swarm of active calls/referrals and reduced the utter bevy of referrals by identically half.

Conclusions: Use of a GALT cutoff of ≤40 µmol/L/L and a Gal cutoff of ≥1.665 mmol/L (≥30 mg/dL) for begging notification/referral dramatically reduces unsound positives and supererogatory follow-up, thereby reducing the forcefulness on healthcare resources.

Background: Although octanoylcarnitine (C8) concentrations regulated from newborn screening dried blood spots are occupied to sort out those at high risk of medium-chain acyl-CoA dehydrogenase deficiency (MCADD), age-related testimonial values are currently not within reach for unsophisticated newborn populations. Because age at sampling may restyle within and messenger screening programs, variations in C8 concentrations by age may wear screening program performance. We unfaltering whether C8 concentrations vacillate by age at sampling, sex, extraction weight, or gestational age in genuine newborns.

Methods: We analyzed C8 concentrations from 227 098 real newborns, including 179 729 from 6 English laboratories participating in a multicenter reading and 47 369 from the unattached laboratory serving the New South Wales (NSW) Newborn Screening Program in Australia. In England, the majority of samples were confident at age 5–8 days and analyzed underivatized by use of tandem bulk spectrometry (MS/MS); in NSW, samples were obtained at a median age of 3 days and analyzed derivatized by MS/MS. Information on infants’ sex, birth weight, gestation, hospitalization, and transfusion importance was recorded at time of sampling.

Results: C8 concentrations did not diverge significantly by age at sampling, sex, creation weight, or gestational age and remained to some degree unshakeable during the at the start 2 weeks of life in unconcerned by babies being screened for MCADD.

Conclusions: Newborn MCADD screening programs using this biomarker for screening samples composed after the maiden day and during the maiden 14 days of passion do not need to fasten cutoff values to account for postnatal age, prematurity, or bigness at confinement.

Background: Newborn screening is a state-based unconcealed healthiness program accepted as a means for the advanced detection and treatment of definite medical conditions to pare down developmental unfitness and mortality. The program was initiated more than 40 years ago to perceive and impede phenylketonuria. Late technological advances have expanded the extent of newborn screening to allow for more than 30 ingrained errors of metabolism. Cogitation is now being stated to incorporation of screening for lysosomal storage disorders (LSDs).

Content: Some lysosomal storage disorders (LSDs) force out cock's-crow in stages or teens and are treatable. Inauguration of treatment in presymptomatic patients or in syptomatic patients prior to self-absorbed symptoms are immediate may reform the long-term Medicine sequela usually|sequelae. Therefore, pioneer diagnosis is perilous. Based on the availability of remedial programme and increment of a screening method, 6 of the more than 40 familiar LSDs are candidates for newborn screening in the US: Gaucher disease, Pompe disease, Fabry disease, Niemann-Pick disease, mucopolysaccharidosis I, and Krabbe affliction. This gunfire reviews the experiences of newborn screening, the technology that has allowed for expanded screening during the mould decade, LSDs and their treatment, and the evolving methods that influence appropriate additional expansion of newborn screening to count definite LSDs.

Summary: Late and evolving technological advances may be implemented for newborn screening for LSDs. This screening desire identify presymptomatic newborns, allowing for early treatment and debarring or limitation of morbidity in another situation associated with these inherited rare diseases.