Molecular characterization of novel and rare DNA variants in patients with galactosemia.

Introduction: Galactosemia is an inherited disorder caused by mutations in the three genes that encode enzymes implicated in galactose catabolism. Currently, the only available treatment for galactosemia is life-long dietary restriction of galactose/lactose, and despite treatment, it might result in long-term complications. Methods: Here, we present five cases of newborn patients with elevated galactose levels, identified in the context of the newborn screening program. Genetic analysis concerned a next generation sequencing (NGS) methodology covering the exons and adjacent splice regions of the GALT, GALK1, and GALE genes. Results: Our approach led to the identification of eight rare nonsynonymous DNA variants. Four of these variants, namely, p.Arg204Gln and p.Met298Ile in GALT, p.Arg68Leu in GALK1, and p.Ala180Thr in GALE, were already recorded in relevant databases, yet their clinical significance is uncertain. The other four variants, namely, p.Phe245Leu in GALT, p.Gly193Glu in GALK1, and p.Ile266Leu and p.Ala216Thr in the GALE gene, were novel. In silico analysis of the possible effect of these variants in terms of protein function and stability was performed using a series of bioinformatics tools, followed by visualization of the substituted amino acids within the protein molecule. The analysis revealed a deleterious and/or destabilizing effect for all the variants, supported by multiple tools in each case. Discussion: These results, given the extreme rarity of the variants and the specific phenotype of the respective cases, support a pathogenic effect for each individual variant. Altogether, our study shows that targeted NGS methodologies may offer a time- and cost-effective approach for the genetic investigation of galactosemia and can assist in elucidating the complex genetic background of this disorder.

Non-inferiority of liquid thyroxine in comparison to tablets formulation in the treatment of children with congenital hypothyroidism.

OBJECTIVES: The aim of the current prospective randomized control study was to assess efficacy, safety, and non-inferiority of a new liquid L-thyroxine formulation dissolved in glycerol and water (T4® drops, produced by a Greek pharmaceutical Company, Uni-Pharma, Athens, Greece) in comparison to the standard Tablets form (T4® tablets, Uni-Pharma, Athens, Greece) in the substitutive treatment of children with congenital hypothyroidism (CH). METHODS: Thirty-nine children with CH, aged 3-12 years old, were enrolled in the study, after parental Informed Consent has been obtained, while three patients were lost from follow-up. At baseline, all participants had normal thyroid-stimulating hormone (TSH) and Free T4 values. Patients were randomly subdivided according to the assigned treatment in Group A (n=17)-Tablet Form and Group B (n=19)-Liquid Form. TSH and Free T4 levels were evaluated at 0, 2, 4, and 6 months. RESULTS: TSH values showed a statistically significant difference (p=0.017) between groups only at six months (Group A having higher TSH levels than Group B, albeit within the normal range), while Free T4 levels had no statistical difference throughout the six month study period and were always within the normal range. Moreover, dose adjustments were more frequent in Group A (p=0.038) during the six months. Liquid L-thyroxine substitutive treatment exhibited no statistically significant adverse effects in comparison to the widely used tablets. CONCLUSIONS: Levothyroxine (LT4) as liquid solution formulation is safe and noninferior to the widely used L-thyroxine Tablets, with less need for dose adjustment, and can therefore be safely used in the treatment of children with CH.

Regulatory landscape of providing information on newborn screening to parents across Europe.

Newborn screening (NBS) is an important part of public healthcare systems in many countries. The provision of information to parents about NBS is now recognised as an integral part of the screening process. Informing parents on all aspects of screening helps to achieve the benefits, promote trust and foster support for NBS. Therefore, policies and guidelines should exist to govern how the information about NBS is provided to parents, taking into account evidence-based best practices. The purpose of our survey was to explore whether any legally binding provisions, guidelines or recommendations existed pertaining to the provision of information about NBS to parents across Europe. Questions were designed to determine the regulatory process of when, by whom and how parents should be informed about screening. Twenty-seven countries participated in the survey. The results indicated that most countries had some sort of legal framework or guidelines for the provision of information to parents. However, only 37% indicated that the provision of information was required prenatally. The majority of countries were verbally informing parents with the aid of written materials postnatally, just prior to sample collection. Information was provided by a neonatologist, midwife or nurse. A website dedicated to NBS was available for 67% of countries and 89% had written materials about NBS for parents. The survey showed that there is a lack of harmonisation among European countries in the provision of information about NBS and emphasised the need for more comprehensive guidelines at the European level.

Adrenal Steroids in Female Hypothyroid Neonates: Unraveling an Association Between Thyroid Hormones and Adrenal Remodeling.

CONTEXT: The adrenal gland undergoes substantial remodeling during the neonatal period, an essential developmental process that remains incompletely understood. With respect to control over the remodeling process and, specifically, the role of thyroid hormones (THs), no human studies have been published. The effects of both hypo- and hyperthyroidism have only been evaluated in adults, focusing on the mature adrenal. Recent studies have identified expression of the TH receptor ß1 in the mouse adrenal X-zone and have demonstrated that TH administration could alter the postnatal adrenal remodeling process. OBJECTIVE: To address whether THs influence adrenal steroid profiles and adrenal remodeling during the neonatal period. METHODS: We compared the adrenal steroid profile of a naturally occurring prototype, female neonates with severe congenital hypothyroidism (CH) (n = 22, upon diagnosis of CH), with that of euthyroid neonates (n = 20). RESULTS: Significantly higher levels of adrenal steroids (17-OH-progesterone, dehydroepiandrosterone sulfate, Δ4-androstenedione, and testosterone) were measured in neonates with severe CH compared with euthyroid neonates and returned to within normal range after euthyroid state had been established on l-thyroxine replacement therapy, whereas cortisol levels did not differ. TSH values in the CH group were positively correlated with circulating adrenal steroids, whereas free T4 levels were negatively correlated with circulating adrenal steroids. CONCLUSIONS: The hormonal profile of female neonates with severe CH suggests a more active adrenal fetal zone compared with control subjects. These data indirectly associate THs with the adrenal remodeling and maturation process in humans. Based on our results, we suggest that severe hypothyroidism decelerates the involution of the adrenal fetal zone that normally occurs postnatally.

Screening for congenital hypothyroidism: the significance of threshold limit in false-negative results.

CONTEXT: In our neonatal program, a number of infants with congenital hypothyroidism (CH) had escaped diagnosis, when a spot RIA-TSH value of 20 mU/liter whole blood was used as a cutoff point. OBJECTIVE: The objective of the study was to find out prospectively the additional number of newborns with CH if the TSH cutoff point is lowered to 10 mU/liter. POPULATION AND METHODS: The study included 311,390 screened newborns. The children with CH were followed up for a period of 3 yr. RESULTS: Twenty-eight percent of infants diagnosed with CH had neonatal TSH values between 10 and 20 mU/liter (56 of 200). Forty of 47 infants, who were reevaluated later on (85.1%), suffered permanent CH. A thyroid scintiscan and/or echogram revealed that eight of 40 children (20.0%) had a structural defect, and the remaining (32 of 40) had a functional defect of the thyroid gland without anatomical abnormality; 14 of 32 cases were familial. Eighteen of the 47 reevaluated infants were prematurely born (38.3%) and 15 of these 18 had permanent CH (83.3%). The lowering of TSH cutoff point from 20 to 10 mU/liter resulted in a 10-fold increase of recall rate. CONCLUSIONS: A significant number of cases with permanent CH are missed when a TSH threshold of 20 mU/liter is applied. Almost 40% of the missed CH cases were premature. A mild increase of TSH at screening is not a predictor of transient CH. The increase in recall rate constitutes a serious drawback and should be balanced against the possible consequences of thyroid dysfunction at this important developmental stage.

Transient congenital hypothyroidism due to maternal autoimmune thyroid disease.

The neonatal screening program for congenital hypothyroidism (CH) in Greece shows an overall incidence of the disease of 1:2321. The cases with permanent CH have an incidence of 1:2542, whereas the transient forms of CH account for 8.7% of all cases diagnosed as CH. Transplacental passage of maternal thyrotropin receptor-blocking antibodies is a rare cause of transient CH. In our program, a retrospective analysis of 508,358 screened newborns revealed 6 infants with transient CH caused by maternal thyroid autoimmunity, representing 2.7% of all cases of CH. All the newborns with transient CH, due to maternal autoimmune thyroid disease, had high serum TSH concentration (ranging from 98 to 689 mU/L), whereas serum thyroxine (T4) values were low normal to normal in 3 of them. Replacement therapy with L-thyroxine was initiated at a mean age of 6.5 days. The newborns with transient CH belonged to 4 families, one of which had 4 and another 2 children with the same pathology. Thyrotropin-receptor antibodies (TSH-R Abs), present at the initial examination in newborns' serum, had disappeared from the infants' circulation by the third month of life. One mother carried the Abs for at least 8 years during which period she delivered four babies. The diagnosis of transient CH should be suspected if the mother has autoimmune thyroid disease, if there are siblings with transient CH or if there is no need for an increase in L-thyroxine dose with advancing age. The diagnosis is very important for genetic counseling, early treatment initiation of subsequent offspring and adequate control of the mother's thyroid function during subsequent pregnancies so that any neurodevelopmental abnormality of the fetus could be avoided.