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Galactosemia is an inborn disorder of carbohydrate metabolism of which early detection can prevent severe illness. Although the assay for galactose-1-phosphate uridyltransferase (GALT) enzyme activity has been available since the 1960s, many issues prevented it from becoming universal. In order to develop the Israeli newborn screening pilot algorithm for galactosemia, flow injection analysis tandem mass spectrometry measurement of galactose-1-phosphate in archived dried blood spots from newborns with classical galactosemia, galactosemia variants, epimerase deficiency, and normal controls, was conducted. Out of 431 330 newborns screened during the pilot study (30 months), two with classical galactosemia and four with epimerase deficiency were identified and confirmed. Five false positives and no false negatives were recorded. Following this pilot study, the Israeli final and routine newborn screening algorithm, as recommended by the Advisory Committee to the National Newborn Screening Program, now consists of galactose-1-phosphate measurement integrated into the routine tandem mass spectrometry panel as the first-tier screening test, and GALT enzyme activity as the second-tier performed to identify only newborns suspected to be at risk for classical galactosemia. The GALT enzyme activity cut-off used in the final algorithm was lowered in order to avoid false positives.

Severe iodine deficiency during pregnancy has substantial hormonal consequences, such as fetal brain damage. Data on the potential effects of mild-to-moderate iodine deficiency on the thyroid function of pregnant women and their newborns are scarce and divergent. We investigated the association between iodine intake in pregnancy and maternal and neonatal thyroid function in a region with mild-to-moderate iodine deficiency. Pregnant women’s iodine status was evaluated using an iodine food frequency questionnaire, serum thyroglobulin (Tg), and urinary iodine concentration (UIC). Neonatal thyrotropin (nTSH) values were measured after birth. Obstetrics and anthropometric data were also collected. Among the 178 women (median age 31 years) included in the study, median (interquartile range) estimated dietary iodine intake, Tg and UIC were 179 (94–268) μg/day, 18 (11–33) μg/L, and 60 (41–95) μg/L, respectively. There was a significant inverse association of iodine intake with Tg values among the study population (β = −0.2, F = 7.5, p < 0.01). Women with high free triiodothyronine (FT3) values were more likely to exhibit an estimated iodine intake below the estimated average requirement (160 μg/day, odds ratio [OR] = 2.6; 95% confidence interval [CI], 1.1–6.4; p = 0.04) and less likely to consume iodine-containing supplements (OR = 0.3, 95% CI, 0.1–0.8; p = 0.01). It is possible that thyroid function may be affected by iodine insufficiency during pregnancy in regions with mild-to-moderate iodine deficiency. The relatively small sample size of the studied population warrants further investigation.

Performing thyroid function tests (TFT) at 2 weeks of age in neonates of mothers with hypothyroidism, despite having a newborn screening program, is a debated approach. We examined whether there is an additional clinical benefit in TFT at 2 weeks of age in neonates born to mothers with hypothyroidism, in addition to the neonatal screening program. We performed a retrospective study which included all newborns of mothers with a diagnosis of hypothyroidism and gave birth in a single regional hospital between the years 2010 and 2016. Data were collected from a computerized medical record system of the hospital and the community clinics, and from Israel's national newborn screening program. Main outcome measure was results of serum TFT in comparison to the results of the neonatal screening test. There were 1392 newborns eligible according to the study criteria. Of these, 1033 underwent a newborn screening test, and serum TFT at least 2 weeks after birth. Eight babies with congenital hypothyroidism were detected independently by both the newborn screening program and at the TFT performed at 2 weeks of age.Conclusions: No added clinical benefit was found in retesting newborns of hypothyroid mothers for thyroid function in addition to the newborn screening program. What is Known • Performing thyroid function test 2 weeks after birth is a common practice in newborn to a mother with hypothyroidism. • Neonatal screening program for thyroid function is also done in these newborns. What is New • No newborn was found to have a normal newborn screening test but abnormal serum thyroid function test. • No added clinical benefit was found in retesting newborns of hypothyroid mothers for thyroid function in addition to the newborn screening program.

Introduction Maternal thyroid disease is considered as a risk factor for abnormal thyroid function at birth, as well as for long-term morbidity in offspring. The potential harmful effects on the neonate had led to the clinical practice of thyroid function assessment in infants born to mothers with thyroid disease during pregnancy. In this study, we evaluated the usefulness of routine thyroid function tests for every newborn of a mother with thyroid dysfunction. Methods Data were collected retrospectively from the medical files of mothers diagnosed with thyroid disease and their infants (496 mother–neonate pairs). All mothers with diagnosed thyroid disease who gave birth in the years 2016–2019 at our medical center were included. Results Hypothyroidism was the most common maternal diagnosis (91.4%), among which 48.7% had Hashimoto’s thyroiditis. Hyperthyroidism was diagnosed in 8.6% of the cohort – 71.6% of them with Graves’ disease. None of the newborns was diagnosed with congenital hypothyroidism in the screening program. Thyroid-stimulating hormone was >10 mIU/L in 14.6% and >20 mUI/L in 2.2%; all had free thyroxine within normal range. Serum thyroid function test identified four infants with thyroid disease; two had congenital hypothyroidism not related to maternal thyroid disease, one had transient familial congenital hypothyroidism and one had neonatal Graves’ disease. Conclusions Thyroid function testing for all newborns of mothers with thyroid dysfunction seems redundant. However, in cases of congenital hypothyroidism in siblings, thyroid function test, in addition to newborn thyroid screening, is recommended, and more careful follow-up is indicated. In maternal Graves’ disease, thyroid function test on days 2–3 of life is recommended.

Urea cycle disorders (UCDs), including OTC deficiency (OTCD), are life-threatening diseases with a broad clinical spectrum. Early diagnosis and initiation of treatment based on a newborn screening (NBS) test for OTCD with high specificity and sensitivity may contribute to reduction of the significant complications and high mortality. The efficacy of incorporating orotic acid determination into routine NBS was evaluated. Combined measurement of orotic acid and citrulline in archived dried blood spots from newborns with urea cycle disorders and normal controls was used to develop an algorithm for routine NBS for OTCD in Israel. Clinical information and genetic confirmation results were obtained from the follow-up care providers. About 1147986 newborns underwent routine NBS including orotic acid determination, 25 of whom were ultimately diagnosed with a UCD. Of 11 newborns with OTCD, orotate was elevated in seven but normal in two males with early-onset and two males with late-onset disease. Orotate was also elevated in archived dried blood spots of all seven retrospectively tested historical OTCD patients, only three of whom had originally been identified by NBS with low citrulline and elevated glutamine. Among the other UCDs emerge, three CPS1D cases and additional three retrospective CPS1D cases otherwise reported as a very rare condition. Combined levels of orotic acid and citrulline in routine NBS can enhance the detection of UCD, especially increasing the screening sensitivity for OTCD and differentiate it from CPS1D. Our data and the negligible extra cost for orotic acid determination might contribute to the discussion on screening for proximal UCDs in routine NBS.

Objective To assess the clinical and neurological outcomes in newborns with primary congenital hypothyroidism presented with delayed TSH elevation (dTSH), and to define parameters that may predict the evolution of transient vs. permanent hypothyroidism in these newborns. Design and patients An observational study was performed of a cohort of 113 children with a history of dTSH. Measurements Birth parameters, thyroid screening results, thyroid gland imaging, levothyroxine dose and neurological outcome were compared between newborns with spontaneous recovery and children with a final diagnosis of either transient or permanent hypothyroidism. Results Of the children with a history of dTSH, 93% demonstrated recovery, either spontaneously or following levothyroxine treatment (transient hypothyroidism). Newborns with spontaneous recovery demonstrated milder thyroid dysfunction at the newborn screening compared to those who started levothyroxine treatment. Levothyroxine dose was lower in children with transient vs. permanent hypothyroidism only during the first 6 months of life; otherwise, these groups were similar in birth parameters, thyroid screening results and gland images. Seventeen out of 61 children (28%) that underwent neurological assessment demonstrated a developmental delay. Duration of treatment was highly variable in children with transient hypothyroidism. Conclusions Thyroid dysfunction is transient in most cases of dTSH. No reliable parameters can predict a priori transient vs. permanent hypothyroidism.

Objective The aim of the study is to evaluate the effect of the coronavirus disease 2019 (COVID-19) pandemic national lockdown period on the rate of singleton preterm births in Israel. Study Design This is a population-based cohort study of 3,41,291 singleton infants born in the months of January to July 2017 to 2020. Multivariable logistic regression analyses were used to estimate the influence of period and year on the rates of preterm births during the lockdown period (11th March − 5th May 2020) compared with rates before (January 1st 2020 − March 10th 2020), and after the lockdown (May 6th 2020–June 30th 2020) and to the corresponding periods in 2017to 2019. Results During the lockdown period the preterm birth rate (primary outcome) decreased by 9.7% from 5.05 to 4.56% in the pre-lockdown period (p = 0.006), an adjusted decrease of −0.52% (95% confidence interval −0.89%; −0.15%), odds ratio 0.898 (95% confidence interval 0.832; 0.970). Conclusion The rate of singleton preterm births declined by 9.7% during the COVID-19 pandemic national lockdown period in Israel. Key Points

Introduction: Thyroid peroxidase (TPO) deficiency is the most common enzymatic defect causing congenital hypothyroidism (CH). We aimed to characterize the long-term outcome of patients with TPO deficiency. Methods: Clinical and genetic data were collected retrospectively. Results: Thirty-three patients with primary CH caused by TPO deficiency were enrolled. The follow-up period was up to 43 years. Over time, 20 patients (61%) developed MNG. Eight patients (24%) underwent thyroidectomy: one of them had minimal invasive follicular thyroid carcinoma. No association was found between elevated lifetime TSH levels and the development of goiter over the years. Conclusions: This cohort represents the largest long-term follow up of patients with TPO deficiency. Our results indicate that elevated TSH alone cannot explain the high rate of goiter occurrence in patients with TPO deficiency, suggesting additional factors in goiter development. The high rate of MNG development and the risk for thyroid carcinoma indicate a need for long-term follow up with annual ultrasound scans.

International audience; Neonatal screening (NBS) was initiated in Europe during the 1960s with the screening for phenylketonuria. The panel of screened disorders ("conditions") then gradually expanded, with a boost in the late 1990s with the introduction of tandem mass spectrometry (MS/MS), making it possible to screen for 40-50 conditions using a single blood spot. The most recent additions to screening programmes (screening for cystic fibrosis, severe combined immunodeficiency and spinal muscular atrophy) were assisted by or realised through the introduction of molecular technologies. For this survey, we collected data from 51 European countries. We report the developments between 2010 and 2020 and highlight the achievements reached with the progress made in this period. We also identify areas where further progress can be made, mainly by exchanging knowledge and learning from experiences in neighbouring countries. Between 2010 and 2020, most NBS programmes in geographical Europe matured considerably, both in terms of methodology (modernised) and with regard to the panel of conditions screened (expanded). These developments indicate that more collaboration in Europe through European organisations is gaining momentum. We can only accomplish the timely detection of newborn infants potentially suffering from one of the many rare diseases and take appropriate action by working together.

Small for gestational age (SGA) and large for gestational age (LGA) newborns are at increased risk for developmental, metabolic and cardiovascular morbidities.To compare the metabolic biomarkers of SGA and LGA infants with those of appropriate for gestational age (AGA) newborns in order to shed more light on a possible pathogenesis of those morbidities.An observational retrospective study.70,809 term newborns divided into AGA, SGA, LGA, and severe subcategories (3rd percentile or ≥97th percentile).18 metabolites were measured by dried blood tandem mass spectrometry and compared in between groups in univariate and multivariate logistic regression.SGA newborns had a significant likelihood for elevated methionine, proline, free carnitine, and reduced valine levels compared to AGA newborns (P .0001). Severe SGA showed more apparent trends including elevated leucine. LGA newborns had a significant likelihood for low citrulline, glutamine, proline, tyrosine, and elevated leucine levels (P ≤ .0033). Severe LGA newborns showed the same trends, with the exception of citrulline and glutamine.SGA and LGA newborns demonstrate distinct metabolic biomarkers in newborn screening. Most of the altered metabolites in the SGA group were elevated while those in the LGA group were decreased in comparison to AGA newborns. These trends were more apparent in the severe SGA subgroup while they mostly remained the same in the severe LGA subgroup. Whether these metabolic changes are involved with or can predict long-term outcome awaits further trials.

Background: An association between hearing impairment (HI) and congenital hypothyroidism (CH) has been reported previously. However, in general, studies were retrospective and had small sample sizes, and the results were variable and inconclusive. The aim of our study was to assess the prevalence of HI among patients with CH and to examine factors potentially predictive of HI including severity of CH, etiology of CH, and timing of treatment initiation. Methods: Audiometry was undertaken prospectively in 66 patients aged 3–21 years diagnosed with primary CH and 49 healthy matched controls. All patients with HI underwent examination by an otolaryngologist, and in patients with sensorineural loss, brainstem evoked response audiometry was performed. A next-generation sequencing (NGS) panel for genes involved in deafness was performed in patients with sensorineural HI to exclude additional genetic etiologies. Results: HI was found in 19 patients (28.7%). Among them, 5 (7.6%) had moderate to severe bilateral sensorineural impairment and 14 (21.2%) had mild conductive HI. Conductive HI was bilateral in 5 of these patients (36%). None of the controls had HI. No specific etiology was found in patients with HI, and no differences were identified in age at diagnosis, age at initiation of levothyroxine (LT4) therapy, gender, or ethnicity between patients with and without HI. A nonsignificant trend toward lower mean screening TT4 levels was found in patients with HI (compared to those without HI) (3.42 vs. 5.34 μg/dL, p = 0.095). No pathogenic variants in genes attributed to HI were identified by NGS in the 5 patients with sensorineural deafness, indicating that HI in these patients was likely attributable to CH rather than other genetic etiologies. Conclusions: Our findings indicate a high prevalence of HI among patients with CH, predominantly of the conductive type. HI was not associated with the etiology of CH or with delayed initiation of LT4 therapy. Audiometry is recommended for children diagnosed with CH and repeat monitoring may be warranted to identify acquired HI and to prevent long-term sequelae of undiagnosed deafness.

Newborn screening (NBS) programs for severe combined immunodeficiency (SCID), using the TREC-based assay, have enabled early diagnosis, prompt treatment, and eventually changed the natural history of affected infants. Nevertheless, it was believed that some affected infants with residual T cell, such as patients with MHC II deficiency, will be misdiagnosed by this assay. A full immune workup and genetic analysis using direct Sanger sequencing and whole exome sequencing have been performed to a patient that was identified by the Israeli NBS program for SCID. The patient was found to have severe CD4 lymphopenia with an inverted CD4/CD8 ratio, low TREC levels in peripheral blood, abnormal response to mitogen stimulation, and a skewed T cell receptor repertoire. HLA-DR expression on peripheral blood lymphocytes was undetectable suggesting a diagnosis of MHC II deficiency. Direct sequencing of the RFX5 gene revealed a stop codon change (p. R239X, c. C715T), which could cause the patient's immune phenotype. His parents were found to be heterozygote carriers for the mutation. Whole exome sequencing could not identify other potential mutations to explain his immunodeficiency. The patient underwent successful conditioned hematopoietic stem cell transplantation from healthy matched unrelated donor and is currently well and alive with full chimerism. Infants with MHC class II deficiency can potentially be identified by the TREC-based assay NBS for SCID. Therefore, MHC II molecules (e.g., HLA-DR) measurement should be part of the confirmatory immune-phenotyping for patients with positive screening results. This will make the diagnosis of such patients straightforward.

Some neonates develop idiopathic hyperbilirubinemia (INHB) requiring phototherapy, yet with no identifiable causes. We searched for an association between abnormal thyroid levels after birth and INHB.Of 5188 neonates, 1681 (32.4%) were excluded due to one or more risk factors for hyperbilirubinemia. Total thyroxine (TT4) and thyroid stimulating hormone values were sampled routinely at 40-48 hours of age and measured in the National Newborn Screening Program.Of the 3507 neonates without known causes for hyperbilirubinemia, 61 (1.7%) developed INHB and received phototherapy. Univariate analyses found no significant association between mode of delivery and INHB (vacuum-delivered neonates were a priori excluded). Nonetheless, in cesarean-delivered (CD) neonates, two variables had significant association with INHB: TT4 ≥ 13 µg/dL and birth at 38-38.6 weeks. In vaginally delivered (VD) born neonates, INHB was associated with weight loss 7.5% up to 48 hours of age. Multivariate logistic regression analysis showed a strong effect of mode of delivery on possible significant association with INHB. In CD neonates, such variables included: TT4 ≥ 13 µg/dL [P = 0.025, odds ratio (OR) 5.49, 95% confidence interval (CI) 1.23-24.4] and birth at 38-38.6 weeks (P = 0.023, OR 3.44, 95% CI 1.19-9.97). In VD neonates, weight loss 7.5% (P = 0.019, OR 2.1, 95% CI 1.13-3.83) and 1-min Apgar score 9 (P 0.001, OR 3.8, 95% CI 1.83-7.9), but not TT4, showed such an association.INHB was significantly associated with birth on 38-38.6 week and TT4 (≥ 13 µg/dL) in CD neonates, and with a weight loss 7.5% in VD neonates. We herein highlight some acknowledged risk factors for neonatal hyperbilirubinemia, and thus minimize the rate of INHB.

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a fatty acid and amino acid oxidation defect caused by a deficiency of the electron-transfer flavoprotein (ETF) or the electron-transfer flavoprotein dehydrogenase (ETFDH). There are three phenotypes of the disease, two neonatal forms and one late-onset. Previous studies have suggested that there is a phenotype–genotype correlation. We report on six patients from a single Bedouin tribe, five of whom were sequenced and found to be homozygous to the same variant in the ETFDH gene, with variable severity and age of presentation. The variant, NM_004453.3 (ETFDH): c.524G>A, p.(R175H), was previously recognized as pathogenic, although it has not been reported in the literature in a homozygous state before. R175H is located near the FAD binding site, likely affecting the affinity of FAD for EFT:QO. The single homozygous ETFDH pathogenic variant was found to be causing MADD in this cohort with an unexpectedly variable severity of presentation. The difference in severity could partly be explained by early diagnosis via newborn screening and early treatment with the FAD precursor riboflavin, highlighting the importance of early detection by newborn screening.

1. Galit Tal, MD* 2. Dalit E. Dar, PhD† 3. Shlomo Almashanu, PhD‡ 4. Stanley H. Korman, MBBS* 5. Elena Dumin, MD, PhD†,§ 1. *Metabolic Unit, Ruth Rappaport Children's Hospital, Rambam Health Care Campus, Haifa, Israel 2. †Department of Clinical Biochemistry, Rambam Health Care Campus, Haifa, Israel 3. ‡National Newborn Screening Program, Ministry of Health, Tel HaShomer, Israel 4. §Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel A 2-month-old girl presents with jaundice, pallor, and abdominal distention. She was born by normal delivery at term weighing 2,380 g. Her 22-month-old brother has tyrosinemia type I detected on newborn screening (NBS) and subsequently confirmed by the presence of succinylacetone on a urine organic acid analysis and demonstration of homozygosity for the IVS8-1(g-c) mutation in the FAH gene. He is doing well and has normal liver function on standard treatment with NTBC (nitisinone) and a tyrosine- and phenylalanine-restricted diet. The parents are first cousins of Christian Arab origin from the north of Israel and confirmed to be heterozygous for the FAH mutation. Prenatal genetic diagnosis performed in the latest pregnancy on chorionic villus sampling indicated that the girl is a heterozygous carrier for the FAH mutation. Findings from her NBS were completely normal, including a negative test for succinylacetone. She is being bottle-fed with a regular infant formula. On examination she looks pale and sweaty, although alert. Her abdomen is swollen but not tender, with a firm liver edge palpable below the costal margin, spleen not palpable. Initial laboratory results (Table) reveal a blood sugar level of 34 mg/dL (1.9 mmol/L), elevated hepatocellular and cholestatic liver enzyme levels, direct hyperbilirubinemia, hypoalbuminemia, and abnormal coagulation studies consistent with synthetic liver failure. She …

Background Maple syrup urine disease is a rare autosomal-recessive aminoacidopathy, caused by deficient branched-chain 2-keto acid dehydrogenase (BCKD), with subsequent accumulation of branched-chain amino acids (BCAAs): leucine, isoleucine and valine. While most cases of MSUD are classic, some 20% of cases are non-classic variants, designated as intermediate- or intermittent-types. Patients with the latter form usually develop normally and are cognitively intact, with normal BCAA levels when asymptomatic. However, intercurrent febrile illness and catabolism may cause metabolic derailment with life-threatening neurological sequelae. Thus, early detection and dietary intervention are warranted in intermittent MSUD. Patients and methods We describe eight patients from four unrelated families, diagnosed with intermittent MSUD. Their presenting symptoms during metabolic crises varied from confusion and decreased consciousness, to ataxia, and acute psychosis. Molecular confirmation of MSUD was pursued via sequencing of the BCKDHA, BCKDHB and DBT genes. Results All affected individuals were found to harbor bi-allelic pathogenic variants in either BCKDHB or DBT. Of the seven variants, four variants in BCKDHB (p.G101D, p. V103A, p. A221D, p. Y195C) and one variant in DBT (p.K427E) were not previously described. Conclusions While newborn screening programs allow for early detection of classic MSUD, cases of the intermittent form might go undetected, and present later in childhood following metabolic derailment, with an array of non-specific symptoms. Our experience with the families reported herein adds to the current knowledge regarding the phenotype and mutational spectrum of this unique inborn error of branched-chain amino acid metabolism, and underscore the high index of suspicion required for its diagnosis.

Context Congenital adrenal hyperplasia (CAH) was among the first genetic disorders included in newborn screening (NBS) programs worldwide, based on 17α-hydroxyprogesterone (17-OHP) levels in dried blood spots. However, the success of NBS for CAH is hampered by high false positive (FP) rates, especially in preterm and low-birthweight infants. Objective To establish a set of cutoff values adjusting for both gestational age (GA) and birthweight (BW), with the aim of reducing FP rates. Design This cross-sectional, population-based study summarizes 10 years of experience of the Israeli NBS program for diagnosis of CAH. Multitiered 17-OHP cutoff values were stratified according to both BW and GA. Participants A total of 1,378,132 newborns born between 2008 and 2017 were included in the NBS program. Results Eighty-eight newborns were ultimately diagnosed with CAH; in 84 of these, CAH was detected upon NBS. The combined parameters-adjusted approach significantly reduced the recall FP rate (0.03%) and increased the positive predictive value (PPV) (16.5%). Sensitivity among those referred for immediate attention increased significantly (94%). There were four false negative cases (sensitivity, 95.4%), all ultimately diagnosed as simple-virilizing. Sensitivity and specificity were 95.4% and 99.9%, respectively, and the percentage of true-positive cases from all newborns referred for evaluation following a positive NBS result was 96%. Conclusions The use of cutoff values adjusted for both GA and BW significantly reduced FP rates (0.03%) and increased overall PPV (16.5%). Based on our 10 years of experience, we recommend the implementation of this two parameter-adjusted approach for NBS of classic CAH in NBS programs worldwide.

Newborn screening (NBS) programs for severe combined immunodeficiency (SCID), the most severe type of primary immunodeficiency, are being implemented in more and more countries with every passing year. Since October 2015, SCID screening via T cell receptor excision circle (TREC) quantification in dried blood spots (DBS) has been part of the Israeli NBS program. As an NBS program in its infancy, SCID screening is still evolving, making gathering input from the various programs crucial for compiling an ideal screening algorithm. The relatively high rate of consanguineous marriages in Israel, especially among non-Jews, correlates with an increased incidence of SCID. The Israeli algorithm uses a commercial kit and consists of a two-Guthrie card confirmation system prior to referral to a national immunology center. Preliminary data from the first year and a half of SCID screening in Israel has identified a surprisingly high prevalence of DNA cross-link repair protein 1c (DCLRE1C; ARTEMIS) mutations as the cause of SCID in Israel. The clinically unbiased nature of SCID screening helps unearth mild/leaky SCID phenotypes, resulting in a better understanding of true SCID prevalence and etiology.

Context Delayed thyrotropin (TSH) elevation (dTSH) is defined as elevated TSH at the second neonatal screening (after normal TSH levels at the initial screening) in premature, low-birth-weight, and ill newborns, mostly in the neonatal intensive care unit (NICU) setting. The pathogenesis of dTSH is elusive. Objective To identify the risk factors for dTSH development among newborns in the NICU. Design, Setting, and Patients A retrospective medical record review of neonates with dTSH was conducted in eight university-affiliated NICUs. Two controls were selected for each patient, matched for sex and birth weight. The risk factors for dTSH were identified by univariate analysis, followed by multivariate analysis. Main Outcome Measures Maternal variables, types of NICU treatments and procedures, syndromes, and various medical conditions were compared between dTSH patients and their matched controls. Results We enrolled 100 dTSH patients and 200 matched controls and 46 variables were compared between the two groups. Twelve risk factors for dTSH were identified on univariate analysis: cesarean section, mechanical ventilation, patent ductus arteriosus (PDA), pneumothorax, and administration of cefotaxime, vancomycin, fluconazole, dopamine, ibuprofen, furosemide, insulin, and packed red blood cells. On multivariate analysis, four risk factors were identified: PDA and vancomycin, insulin, and furosemide administration. In 26 twin pairs, in which one twin had dTSH, all variables presented similarly in both twins. Conclusions Although some variables had direct effects on pituitary–thyroid axis dysfunction, these variables, altogether, reflect the severity of the clinical conditions in the NICU, which is the common basis for dTSH.

To elucidate the incidence, clinical characteristics, and short-term outcome of delayed thyroid stimulating hormone (TSH) elevation (dTSH) in a large cohort of newborns admitted to the neonatal intensive care unit.Data were gathered from a cohort of 13 201 newborns admitted to the neonatal intensive care unit born between January 1, 2008, and October 31, 2014, who underwent TSH measurements because of low T4 levels on the second screen. The data from the newborn screening program included gestational age, birth weight (BW), T4 levels, and short-term outcome.Of 13 201 newborns, 333 (1:40) presented with dTSH (TSH15 IU/L). dTSH had a peak proportion at gestational age of 37-39 weeks, and 66% of the patients had BW1500 g. T4 levels in the 333 patients were negatively correlated with TSH levels (R = -0.505; P .001), and significantly lower than levels in the other newborns: 5.9 ± 2.8 vs 7.6 ± 1.7 µg/dL; P .001. TSH levels in dTSH newborns were already higher on the initial screen compared with the other newborns: 8.3 ± 5.2 vs 4.2 ± 3.7 IU/L; P .001. Fifty-eight percent of 193 patients with dTSH were started on levothyroxine treatment.dTSH has a higher incidence than previously reported, especially among newborns with BW1500 g. Relatively high TSH and low T4 levels on the initial and second screen respectively are predictors for dTSH. Levothyroxine treatment is required in most cases.

Refeeding of elderly frail patients after food deprivation is commonly associated with a high mortality rate.To evaluate the effect of refeeding on metabolite fluctuation of blood carnitine fatty acids (15 compounds) and free amino acids (14 compounds).Metabolite fluctuation was followed up in an exploratory, cohort, and noninterventional study in elderly and frail patients (84.5 ± 5 years) after a long period of food deprivation. Patients in the study group were refed by enteral nutrition (EN) and were followed up during 7 days for blood metabolites (n = 27). Patients in the control group (n = 26) had been fed by EN for more than 3 months. Refeeding was initiated with 10 kcal/kg/d and gradual increases of 200 kcal/d for 3 days afterwards. Blood metabolites were assayed in a sample of 25 µL.On food deprivation, the concentrations of all even monocarboxylic carnitine fatty acids were much higher in the study group than in the EN control group (P.01). Upon refeeding, a remarkable decrease in all carnitine fatty acids was observed. In addition, significant daily fluctuations were observed for most metabolites in the study group of the refed patients as compared with the EN control group (P.01). The highest fluctuations were observed following refeeding in the 7 patients who later died.A significant metabolic instability is observed on refeeding even with a slow refeeding schedule of 10 kcal/kg/d. Measurement of metabolomics parameters may be used for the evaluation of malnutrition, refeeding status, and optimization of the enteral formula.

3-Methylcrotonyl-CoA carboxylase deficiency (3MCCD) is an inborn error of leucine catabolism. Tandem mass spectrometry newborn screening (NBS) programs worldwide confirmed 3MCCD to be the most common organic aciduria and a relatively benign disorder with favorable outcome. In addition, several asymptomatic 3MCCD mothers were initially identified following abnormal screening of their healthy babies and were appropriately termed maternal 3MCCD. This is a retrospective study that summarizes all the clinical, biochemical, and genetic data collected by questionnaires of all 3MCCD individuals that were identified by the extended Israeli NBS program since its introduction in 2009 including maternal 3MCCD cases. A total of 36 3MCCD subjects were diagnosed within the 50-month study period; 16 were classified primary and 20 maternal cases. Four additional 3MCCD individuals were identified following sibling screening. All maternal 3MCCD cases were asymptomatic except for one mother who manifested childhood hypotonia. Most of the primary 3MCCD individuals were asymptomatic except for two whose condition was also complicated by severe prematurity. Initial dried blood spot (DBS) free carnitine was significantly lower in neonates born to 3MCCD mothers compared with newborns with primary 3MCCD (p = 0.0009). Most of the mutations identified in the MCCC1 and MCCC2 genes were missense, five of them were novel. Maternal 3MCCD is more common than previously thought and its presence may be initially indicated by low DBS free carnitine levels. Our findings provide additional confirmation of the benign nature of 3MCCD and we suggest to exclude this disorder from NBS programs.

Background: Loss-of-function mutations in the thyrotropin receptor (TSHR) gene lead to resistance to TSH (RTSH) presenting with either congenital hypothyroidism (CH) or subclinical hypothyroidism (SCH). Despite several reports of patients with TSHR mutations, data on the long-term outcome of this condition are limited, and no consensus exists on the need for hormone replacement therapy. The aim of the present study was to assess the long-term outcome in children and adolescents with RTSH due to TSHR mutations. Methods: The TSHR gene was sequenced in 94 subjects (aged 3 days–21 years) with either nonautoimmune SCH or CH with RTSH. Results: Twenty-seven subjects (29%) carried mutations in TSHR. Fifteen infants were identified by neonatal screening, and the other 79 patients were detected in the process of testing for various other conditions or because of family occurrence of thyroid test abnormalities. Six different mutations were identified: c.484C>G (p.P162A), c.202C>T (p.P68S), c.790C>T (p.P264S), c.269...

PRODH maps to 22q11 in the region deleted in the velocardiofacial syndrome/DiGeorge syndrome (VCFS/DGS) and encodes proline oxidase (POX), a mitochondrial inner-membrane enzyme that catalyzes the first step in the proline degradation pathway. At least 16 PRODH missense mutations have been identified in studies of type I hyperprolinemia (HPI) and schizophrenia, 10 of which are present at polymorphic frequencies. The functional consequences of these missense mutations have been inferred by evolutionary conservation, but none have been tested directly. Here, we report the effects of these mutations on POX activity. We find that four alleles (R185Q, L289M, A455S, and A472T) result in mild (30%), six (Q19P, A167V, R185W, D426N, V427M, and R431H) in moderate (30%-70%), and five (P406L, L441P, R453C, T466M, and Q521E) in severe (70%) reduction in POX activity, whereas one (Q521R) increases POX activity. The POX encoded by one severe allele (T466M) shows in vitro responsiveness to high cofactor (flavin adenine dinucleotide) concentrations. Although there is limited information on plasma proline levels in individuals of known PRODH genotype, extant data suggest that severe hyperprolinemia (800 microM) occurs in individuals with large deletions and/or PRODH missense mutations with the most-severe effect on function (L441P and R453C), whereas modest hyperprolinemia (300-500 microM) is associated with PRODH alleles with a moderate reduction in activity. Interestingly, three of the four alleles associated with or found in schizophrenia (V427M, L441P, and R453C) resulted in severe reduction of POX activity and hyperprolinemia. These observations plus the high degree of polymorphism at the PRODH locus are consistent with the hypothesis that reduction in POX function is a risk factor for schizophrenia.

delta(1)-pyrroline-5-carboxylate synthase (P5CS), a bifunctional ATP- and NADPH-dependent mitochondrial enzyme, catalyzes the reduction of glutamate to delta(1)-pyrroline-5-carboxylate, a critical step in the biosynthesis of proline, ornithine and arginine. Recently, we reported the cloning and expression of human and murine P5CS cDNAs. Previously, we showed that mammalian P5CS undergoes alternative splicing to generate two isoforms differing only by a 2 amino acid insert at the N-terminus of the gamma-glutamyl kinase active site. The short isoform has high activity in the gut, where it participates in arginine biosynthesis and is inhibited by ornithine. The long isoform, expressed in multiple tissues, is necessary for the synthesis of proline from glutamate and is insensitive to ornithine. Here, we describe a newly recognized inborn error due to the deficiency of P5CS in two siblings with progressive neurodegeneration, joint laxity, skin hyperelasticity and bilateral subcapsular cataracts. Their metabolic phenotype includes hyperammonemia, hypoornithinemia, hypocitrullinemia, hypoargininemia and hypoprolinemia. Both are homozygous for the missense mutation, R84Q, which alters a conserved residue in the P5CS gamma-glutamyl kinase domain. R84Q is not present in 194 control chromosomes and dramatically reduces the activity of both P5CS isoforms when expressed in mammalian cells. Additionally, R84Q appears to destabilize the long isoform. This is the first documented report of an inborn error of P5CS and suggests that this disorder should be considered in the differential diagnosis in patients with neurodegeneration and/or cataracts and connective tissue disease.

Enumeration of T cell receptor excision circles (TREC) was recently adopted as a neonatal screening assay for severe combined immunodeficiency (SCID). Enumeration of kappa-deleting recombination excision circle (KREC) copy numbers can be similarly used for early assessment of B cell lymphopenia.To assess the ability of TREC and KREC counts to identify patients with combined T and B cell immunodeficiency in a pilot study in Israel.We studied seven children born in Israel during the years 2010-2011 and later diagnosed with SCID, and an additional patient with pure B cell immunodeficiency. TREC and KREC in peripheral blood upon diagnosis and in their neonatal Guthrie cards were analyzed using real-time quantitative polymerase chain reaction, as were Guthrie cards with dried blood spots from healthy newborns and from normal and SCID-like controls.The first features suggestive of SCID presented at age 3.1 +/- 2.4 months in all patients. Yet, the diagnosis was made 4.1 +/- 2.9 months later. Their TREC were undetectable or significantly low at their clinical diagnosis and in their originally stored Guthrie cards, irrespective of the amount of their circulating T cells. KREC were undetectable in six SCID patients who displayed B cell lymphopenia in addition to T cell lymphopenia. KREC were also undetectable in one patient with pure B cell immunodeficiency.TREC and KREC quantification are useful screening tests for severe T and B cell immunodeficiency. Implementation of these tests is highly important especially in countries such as Israel where a high frequency of consanguinity is known to exist.

Transient tachypnea of newborn is associated with hypothyroxinemia in animals via decreased stimulation of beta-adrenergic receptors and Na-K-ATPase activity. In 26 549 term neonates, serum total thyroxine 14 ug/dL, male sex, and elective cesarean delivery were significantly associated with greater risk for transient tachypnea of newborn.

ObjectiveContradictory reports ascribe neonatal hyperthyrotropinemia (HT) to prematurity or small weight for gestational age. We aimed to evaluate the association between neonatal HT and birth weight (BW), recovery rate of the disorder, and possible association with perinatal stress.DesignBased on a neonatal screening database, a retrospective twin study was designed where within-pair differences in thyroid function were evaluated while controlling for differences in gestational age and thyroid-affecting environmental confounders.MethodsTwo thousand five hundred and ninety-five twin pairs that were screened both for TSH and thyroxine (T4) over 3 years were included. TSH and T4levels were evaluated along with BW, birth order, gender, and 17-hydroxyprogesterone (17OHP) that was considered as a surrogate marker for stress.ResultsOf all the twin pairs, 7.2% had neonatal HT. Among 156 pairs, HT was more prevalent in the smaller twins (64%;PP=0.001). Seventy-five percent of the twins demonstrated a recovery within the first few weeks of life. 17OHP levels were similarly distributed between twins with and without HT. In a cohort of 1534 twin pairs with normal thyroid function, mean TSH levels were significantly higher in the smaller than in the larger twin in the whole group (4.1±3.2 vs 3.8±2.9 mIU/l;PPConclusionsElevated TSH levels are associated with low BW, both in infants with HT and in normal neonates. A rapid recovery rate is expected in most cases.

Deficiency of 3-methylcrotonyl-CoA carboxylase (MCC) results in elevated excretion of 3-methylcrotonylglycine (3-MCG) and 3-hydroxyisovaleric acid (3-HIVA). MCC is a heteromeric mitochondrial enzyme comprising biotin-containing alpha subunits and smaller beta subunits, encoded by MCCA and MCCB, respectively. Mutations in these genes cause isolated MCC deficiency, an autosomal recessive disorder with a variable phenotype that ranges from severe neonatal to asymptomatic adult forms. No reported patients have responded to biotin therapy. Here, we describe two patients with a biochemical and, in one case, clinical phenotype of MCC deficiency, both of whom were responsive to biotin. The first patient presented at 3 months with seizures and progressive psychomotor retardation. Metabolic investigation at 2 years revealed elevated excretion of 3-MCG and 3-HIVA, suggesting MCC deficiency. High-dose biotin therapy was associated with a dramatic reduction in seizures, normalization of the electroencephalogram, and correction of the organic aciduria, within 4 weeks. MCC activity in fibroblasts was 25% of normal levels. The second patient, a newborn detected by tandem-mass-spectrometry newborn screening, displayed the same biochemical phenotype and remained asymptomatic with biotin up to the age of 18 months. In both patients, sequence analysis of the complete open reading frames of MCCA and MCCB revealed heterozygosity for MCCA-R385S and for the known polymorphic variant MCCA-P464H but revealed no other coding alterations. MCCA-R385S is unusual, in that it has a normal amount of MCC alpha protein but confers no MCC activity. We show that MCCA-R385S, but not other MCCA missense alleles, reduces the MCC activity of cotransfected MCCA-wild-type allele. Our results suggest that MCCA-R385S is a dominant negative allele and is biotin responsive in vivo.

Peroxisomes are typically spherical (0.1–1 m diameter), single-membrane-bound organelles present in numbers ranging from a few hundred to a few thousand in most mammalian cells. The pH of the mammalian peroxisome matrix has variously been estimated to be more basic or similar to that of cytosol. The dense, proteinaceous peroxisome matrix contains 50 or more enzymes, which participate in a variety of metabolic pathways including oxidation of straight and branched, very long and long chain fatty acids, synthesis of cholesterol and ether-lipids (for example, plasmalogens) and oxidation of polyamines, D-amino acids, and in non-primates, uric acid. The set of proteins found in the membranes of mammalian peroxisomes includes four half ABC transporters (ALDP, ALDR, PMP70, and P70R) comprising a distinct subset of the superfamily of ABC transporters designated subfamily D. Each has an N-terminal hydrophobic transmembrane domain with multiple transmembrane segments (TMS) and a hydrophilic C-terminal half containing a nucleotide-binding domain (NBD) with Walker A and B motifs. Topology studies indicate that the C-terminal hydrophilic halves of ALDP and PMP70 extend into the cytosol. This chapter reviews peroxisome function, genetic diseases, and biogenesis. It then focuses on the molecular, cellular, and evolutionary biology of the mammalian peroxisomal ABC transporters.

Isolated biotin-resistant 3-methylcrotonyl-CoA carboxylase (MCC) deficiency is an autosomal recessive disorder of leucine catabolism that appears to be the most frequent organic aciduria detected in tandem mass spectrometry-based neonatal screening programs. The phenotype is variable, ranging from neonatal onset with severe neurological involvement to asymptomatic adults. MCC is a heteromeric mitochondrial enzyme composed of biotin-containing alpha subunits and smaller beta subunits. Here, we report cloning of MCCA and MCCB cDNAs and the organization of their structural genes. We show that a series of 14 MCC-deficient probands defines two complementation groups, CG1 and 2, resulting from mutations in MCCB and MCCA, respectively. We identify five MCCA and nine MCCB mutant alleles and show that missense mutations in each result in loss of function.

Neurospora crassa ARG13 and Saccharomyces cerevisiae ARG11 encode mitochondrial carrier family (MCF) proteins that transport ornithine across the mitochondrial inner membrane. We used their sequences to identify EST candidates that partially encode orthologous mammalian transporters. We thereby identified such a gene (ORNT1) that maps to 13q14 and whose expression, similar to that of other urea cycle (UC) components, was high in liver and varied with changes in dietary protein. ORNT1 expression restores ornithine metabolism in fibroblasts from patients with hyperammonaemia-hyperornithinaemia-homocitrullinuria (HHH) syndrome. In a survey of 11 HHH probands, we identified 3 ORNT1 mutant alleles that account for 21 of 22 possible mutant ORNT1 genes in our patients: F188delta, which is common in French-Canadian HHH patients and encodes an unstable protein; E180K, which encodes a stable, properly targeted protein that is inactive; and a 13q14 microdeletion. Our results show that ORNT1 encodes the mitochondrial ornithine transporter involved in UC function and is defective in HHH syndrome.

A novel single base pair deletion in the acid sphingomyelinase (ASM) gene (677delT in the cDNA) was identified in 12 Israeli Arab families with Niemann-Pick disease (NPD) type A. This deletion creates a premature stop codon which explains the complete deficiency of ASM activity in these patients and the severe clinical manifestation. A single mutation in 12 families living in a relatively small geographical region suggests a founder effect and explains the high frequency of this disease in this population. This is in contrast to multiple mutations found in two other lysosomal storage disorders prevalent in this population, namely, Hurler disease (MPSI) and metachromatic leukodystrophy. Mutations analysis is therefore an important tool in characterizing the grounds for the high frequency of inherited diseases as well as a basis for prevention programs for prevalent diseases through carrier identification and the ascertainment of high risk families.