Extrathyroidal congenital defects in children with congenital hypothyroidism - observations from a single paediatric centre in Central Europe with a review of literature.

INTRODUCTION: Patients with congenital hypothyroidism (CH) can have an increased risk of occurrence of extrathyroidal defects compared to the general population, which could influence their development. The abnormalities occur mainly in organ systems whose development and function is dependent on genes that are also responsible for proper organogenesis of the thyroid gland and thyroid hormone synthesis. AIM OF THE STUDY: The aim of the study was to evaluate the frequency of extrathyroidal defects in CH patients, taking into consideration the cause of this co-occurrence and the role of genetic tests. MATERIAL AND METHODS: The study included 54 newborns with positive screening test for CH based on elevated TSH level, in the years 2010-2017, from South-Eastern Poland. The data was retrieved retrospectively from patients' medical records. RESULTS: Twenty of 54 newborns with CH (37%) had congenital defects of other organs. In 10 (18.5%) cardiac defects were found, in 5 (9.25%) abnormal symptoms of the respiratory system, 7 (12.96%) had abnormalities of the gastrointestinal system, five (9.25%) had genitouri-nary abnormalities, 3 (5.55%) had abnormalities of the nervous system, and 6 (11.1%) had musculoskeletal abnormalities. CONCLUSIONS: The analysis of our data and current literature suggests that genetic factors play the most important role in the development of extrathy-roidal abnormalities in newborns with CH. Identifying the mutation causing CH, the potential defects that can accompany newborns with CH, screening could be offered for these patients in order to obtain an earlier diagnosis and implement early and appropriate treat-ment.

Genetic analysis of the paired box transcription factor (PAX8) gene in a cohort of Polish patients with primary congenital hypothyroidism and dysgenetic thyroid glands.

BACKGROUND: The morphological and biochemical phenotype of PAX8 mutation in patients with congenital hypothyroidism (CH) is variable. The contribution of mutations in PAX8 gene in children with CH and dysgenetic thyroid glands still remains a subject of interest for researchers. PATIENTS AND METHODS: Some 48 children (37 girls and 11 boys) with CH associated with thyroid ectopy (n=22), agenesis (n=10), hypoplasia (n=6), or thyroid dysgenesis of unknown cause (n=10) were enrolled. The study participants were born in south-eastern Poland in the years 1993-2012 and were selected for neonatal mass screening for CH. DNA was extracted from peripheral blood samples using Master Pure DNA Purification Kit (Epicentre Biotechnologies, Madison, WI, USA). The 12 exons of the PAX8 gene along with their exon-intron boundaries were amplified and sequenced by the Sanger method. Capillary electrophoresis was run on ABI 3500 (Applied Biosystems, Carlsbad, CA, USA). RESULTS: Novel heterozygous transition in exon 3 (c.68G>A) was detected in a 3-year-old girl with a thyroid hypoplasia. This substitution was not identified in the patient's parents (de novo event). Additionally, a novel genetic variant in 3'UTR region of exon 12 (c.*416C>T) occurred in a 3-year-old boy with ectopic thyroid tissue and concomitant congenital urogenital malformation. This heterozygous variant was also detected in other healthy family members. Thirteen well-described single nucleotide polymorphisms were revealed in the PAX8 gene. CONCLUSIONS: The study reports on the occurrence of two novel heterozygous substitutions in the PAX8 gene. Estimation of the contribution of the revealed c.68G>A variant to the etiology of CH in a girl with hypoplastic thyroid requires further functional analysis.

Identification of deletions in children with congenital hypothyroidism and thyroid dysgenesis with the use of multiplex ligation-dependent probe amplification.

INTRODUCTION: Thyroid dysgenesis (TD) is the most common cause of congenital hypothyroidism (CH). Important genetic factors possibly contributing to TD etiologies include mutations of thyroid transcription factors and TSHR-encoding genes. OBJECTIVE: Our objective was to determine multiplex ligation-dependent probe amplification (MLPA) utility in detecting the copy number changes in patients with CH and TD. METHODS: The study included 45 children from southeastern Poland selected via already established neonatal screening for CH. Genomic DNA was extracted from peripheral blood samples and used in MLPA analysis. Genetic variations were analyzed within selected fragments of the PAX8, FOXE1, NKX2-1, thyroid stimulating hormone receptor (TSHR), and TPO genes. RESULTS: Three heterozygous deletion types in probe hybridization regions were identified for the following genes: PAX8 (exon 7), TSHR (exon 2), and FOXE1 (exon 1). Monoallelic deletions were identified in 5/45 TD subjects. CONCLUSIONS: MLPA is a useful tool for copy number changes detection and might both improve and expand genetic analysis for CH and TD.

Thyroid dysfunctions in children detected in mass screening for congenital hypothyroidism.

BACKGROUND: Congenital hypothyroidism (CH) affects approximately 1:3000-1:4000 infants. OBJECTIVES: To determine the prevalence of CH and isolated hyperthyrotropinemia (IHT) in newborns selected in mass screening for CH. METHODS: Mass screening of 233,120 neonates born in southeastern Poland was carried out and CH-suspected children were identified. Serum thyroid-stimulating hormone and free thyroxine levels were determined during first confirmation and diagnosis re-evaluation in 118 and 34 children, respectively. Additionally, the patients were subjected to thyroid ultrasonography (n=53) and/or scintiscan (n=28). RESULTS: Out of 118 children, first confirmation indicated CH in 58 neonates and IHT in 4 neonates. Out of these, 34 were re-evaluated with regard to diagnosis. A final diagnosis of permanent CH was reported in 34 children with thyroid dysgenesis (n=27) or dyshormonogenesis (n=7), transient CH affected 15 children, and permanent IHT was diagnosed in 6 children. CH prevalence was 1:4570 (permanent 1:6475, transient 1:38,853) and permanent IHT 1:38,853. CONCLUSIONS: The prevalence of CH and IHT corresponds to the prevalence of the condition in iodine-sufficient and borderline iodine-deficient areas.

[Neonatal mass screening for cystic fibrosis in south-east Poland]. / Badania przesiewowe noworodków w kierunku mukowiscydozy w Polsce poludniowo-wschodniej.

UNLABELLED: The objective of neonatal mass screening programs that are obligatory in Poland is an early detection of congenital diseases: hypothyreosis, phenylketonuria and cystic fibrosis. Cystic fibrosis is the most common genetic monogenic disease affecting Caucasian individuals and having an autosomal recessive inheritance pattern. Neonatal screening for cystic fibrosis allows for diagnosing the disease in the first month of life and early introduction of preventive-therapeutic management. In the period between June 1, 2009 and July 31, 2010, a total of 82,250 newborns were screened in the Krakow mass screening lab. METHODS: Determinations of immunoreactive tripsin (IRT) by ELISA, and DNA analysis (searching for mutations in the CFTR gene by sequencing) if IRT was above 99.4 centile in blood on filter paper. The incidence of cystic fibrosis in south-east Poland was determined as 1:7,477, and carriership as 1:2,006. Of newborns with confirmed cystic fibrosis, five presented with signs of malnutrition, edemas, intrahepatic cholestasis and anemia. Almost all of these children passed fatty stools. Two were diagnosed with active CMV infections. CONCLUSIONS: 1) Neonatal mass screening allows for early detection of cystic fibrosis and introduction of appropriate therapeutic management (prevention of malnutrition through supplying appropriate amount of protein, essential fatty acids, pancreatic enzymes and vitamin A and E supplementation). 2) Children are recalled for diagnosis verification immediately after genetic test results are available, what maximally shortens the time needed for confirming the disease.

[Did the change of technique of screening investigations influence on improvement of test credibility in recognizing and differentiating diagnostics of hiperphenylalaninemias?]. / Czy zmiana techniki badan przesiewowych wplynela na poprawe wiarygodnosci testu w rozpoznawaniu i diagnostyce róznicowej hiperfenyloalaninemii?

UNLABELLED: The phenylketonuria (PKU)/hyperphenylalaninemia (HPA) it is the most frequent inborn genetically conditioned error of metabolism of amino acids. It's occurrence in Polish population was estimated on the level 1:7.000 - 8.500. A. Folling was the first who described the phenylketonuria in 1934. It's diagnosed by neonatal screening, which was initiated in 1963 by prof. R. Guthrie. MATERIAL: since 1985 till 2007 1,172,310 newborns investigated by the neonatal screening proceeding by the Laboratory of Screening and Inborn Errors of Metabolism in Cracow. METHOD: in the years 1985-1998 the phenylalanine concentration in drop of blood on the blotting-paper was measured with half-quantitative Guthrie method. However after 1999 the colorimetric quantitative method measurement of phenylalanine concentration in capilar blood was introduced. It 2004 the cut-off value of phenylalanine in drop of blood on filter paper in neonatal screening investigation has was established below 3 mg/dl (till 2003 it was below 4mg/ dl). The blood had been taken from every newborn on filter paper Standard 903 between third and seventh day of the child's life. The verification of recognition in 1985-1988 was applied by Guthrie test, in 1989-2006 by the fluorymetric McCaman and Robins method, and since 2007 by colorimetric method. RESULTS: in 1985-1998 the group of 137 newborns was distinguished due to the newborn screening (1:4.204), the classic PKU was recognized at 96 (1:5.999), however in next years (after change of method) due to screening 186 (1:4.788) newborns were distinguished, the classic PKU was recognized at 94 (1:5.236) newborn children. The lowering the point of cut-off influenced on frequency recognizing mild HPA, which grew up from 1:25.909 to 1:12.720. In 2001 we verified the recognition at 51 of 93 women (data were have gained over from archive of Outpatient Department), who where identified by the neonatal screening in 1985-1998, and in the face of observed phenylalanine values (<10 mg/dl - mild HPA) did not require dietetic treatment, and they gave up with medical care gradually. With regard on possibility pronouncement the signs of maternal PKU at their offspring, we ask 45 of them to contact with our Outpatient Clinic again, but only 36 with different reasons answered, at 28 of them the phenylalanine concentration was raised: 2-4 mg/dl - in 1 patient; 4-6 mg/ dl - in 6 patients; 6-10 mg/dl - in 11 patients; 10-20 mg/dl - in 12 patients. With this reason at 19 women the low-phenylalanine diet had to be introduce. CONCLUSIONS: 1. Applied Guthrie test limited the individual differentiating diagnostics of HPA, which led to relinquishment of medical observation, especially in girls and young women, the birth the child with maternal PKU could be the result of that. 2. Introduction of colorimetric method improved the detecting of the mild PKU and hyperphenylalaninemia considerably.

High prevalence of SURF1 c.845_846delCT mutation in Polish Leigh patients.

Leigh syndrome is a neuropathological disorder with typical morphological changes in brain, appearing regardless of diverse molecular background. One of the most common enzymatic defects in Leigh patients is cytochrome c oxidase deficiency associated with recessive mutations in the SURF1 gene. To assess the SURF1 mutation profile among Polish patients we studied 41 affected children from 34 unrelated families by PCR-SSCP and sequencing. Four novel mutations, c.39delG, c.752-1G>C, c.800_801insT, c.821A>G, and five described pathogenic changes, c.311_312insAT312_321del10, c.688C>T, c.704T>C, c.756_757delCA, c.845_846delCT, were identified in 85.3% of analysed probands. One mutation, c.845_846delCT, was identified in 77.6% of SURF1 alleles. Up to now, it has been reported only in 9% of alleles in other parts of the world. The deletion was used as LS(SURF1-) marker in population studies. Eight heterozygous carriers of the mutation were found in a cohort of 2890 samples. The estimated c.845_846delCT allele frequency is 1:357 (0.28+/-0.2%), and the lowest predicted LS(SURF1-) frequency in Poland 1:126,736.births. Relatively high frequency of LS(SURF1-) in Poland with remarkable c.845_846delCT mutation dominance allows one to start the differential diagnosis of LS in each patient of Polish (and probably Slavonic) origin from the direct search for c.845_846delCT SURF1 mutation.

[Real activity of Kraków endocrine group in Institute of Pediatrics CMUJ on the eradication of IDD in Polish children]. / Aktualny stan dziallan grupy endokrynologów krakowskich Instytutu Pediatrii CMUJ, nad eliminacja chorób z niedoboru jodu (IDD) w Polsce.

The authors present the investigations concerned the Iodine deficiency disorders (IDD) elimination in children living in South-East of Poland in last 15 years. To achieve the full success, what, as we know is possible, the monitoring and the exact control of the salt iodine supplementation according to the National Program of Iodine Deficiency Elimination (1999-2003) should be maintained. To avoid any negligence, the prompt education of the whole population is necessary, but yet especially the pregnant women. It is important to instruct them about the direct influence of iodine deficiency on the mental development of the fetus and the newborn.

Screening for congenital hypothyroidism: the value of retesting after four weeks in neonates with low and very low birth weight.

OBJECTIVES: Thyroid-stimulating hormone (TSH), normally a reliable screening test for congenital hypothyroidism (CH), may fail to detect cases among infants who have low and very low birth weight. The purpose of this study was to identify neonates with false-negative screening results. SETTING: A province in Poland in which 3,854 neonates had body weight or= 10 mIU/L in 19 of the 3,854 low birth weight neonates. The final diagnosis in these neonates was permanent CH in two, transient CH in five, possible compensated CH in six and transient high TSH in six. Of the 19, 16 (84%) required iodine and/or thyroxine replacement therapy. CONCLUSIONS: In neonates with low and very low birth weight, normal TSH levels measured between the third and sixth day of life do not exclude thyroid dysfunction, but a repeat TSH measurement after the fourth week of life identifies the false-negative results. In our data, the prevalence of primary and secondary hypothyroidism (both permanent and transient) was about 0.5%.

Suprasellar arachnoidal cyst as a cause of precocious puberty--report of three patients and literature overview.

The authors present three boys--3 years old, 5.8 years old and 10.4 years old--who were diagnosed with isosexual precocious puberty (IPP) triggered by a rare developmental disorder of suprasellar arachnoid cyst (SAC) accompanied by corpus callosum and fornix dysgenesis as well as anterior commissura magna agenesis (patient 1) and empty sella (patients 2, 3). The reason for diagnostic management recommendation was a rapid progression of IPP signs over one year (patients 1, 2) or 6 months (patient 3) prior to hospitalization, these signs having been present but less intense since infancy (patient 1), 4th year of life (patient 2) and approximately 8 years of age (patient 3). Neurological signs (spastic paresis in patient 1, postural tremor in patient 2 and head bobbing and behavioral changes in patient 3), as well as slowly progressing increased head circumference were observed since neonatal period (patient 1), 1 year old (patient 2) and approximately 4 years old (patient 3). None of the patients manifested hypophyseal-hypothalamic axis dysfunction other than IPP prior to and after surgical management. Shunt implantation resulted in gradual resolution of neurological signs in all patients and in patient 3 also in partial normalization of serum testosterone levels and growth rate. Regression of IPP in patients 1 and 2 was achieved by administration of a long-acting GnRH analogue. Our observations are in accord with data reported by other investigators and confirm the often slow, insidious development of subsequent SAC signs, the type and intensity of which differ from patient to patient. We suggest that some of the neuroanatomical anomalies coexisting with SAC may have a common genesis, or they could under certain conditions be an additional trigger for IPP and possibly other hypothalamopituitary dysfunction.

[TSH levels in newborn with low and very low birth weight vs rescreening for congenital hypothyroidism]. / Analiza poziomów hormonu tyreotropowego u dzieci z niska i bardzo niska urodzeniowa masa ciala a celowosc przeprowadzenia powtórnego badania przesiewowego noworodków w kierunku wrodzonej niedoczynnosci tarczycy.

UNLABELLED: A disorder of thyroid function, as stated by various references, is very common among children with low and very low body weight. Also, the concentration of thyroid hormones in this group differs from that of neonates full term with the adequate body weight. In 1998, in southeastern Poland, a repeated screening for TSH level in blood spots on filter paper was introduced among neonates with low and very low birth-weight. The purpose of this work was the exclusion of late appearing transient hypothyroidism, as well as the verification of falsely positive results in the basic test. Newborns with low and very low birth-weight comprise nearly 5% of live births in the region. During 1998-2001, 4,445 children with body weight below 2500 g were tested. Tests for TSH level in blood on filter paper were carried out in neonates between three and six days of age and also at the end of the first month of life. TSH levels in blood on filter paper were estimated using the LIA method (Byk Sangtec Diagnostica). The results were divided into two groups: those with correct TSH, that is < 15 mIU/L, and those with a raised level 3 15 mIU/L. The repeated test confirmed the correct result in nearly 100% of the neonates, while in 20 (0.5%) showed the increase of TSH level above 15 mIU/L. TSH and fT4 monitoring followed by serum determinations during treatment showed primary hypothyroidism in 10 children and hyperthyrotropinemia in 5 cases. CONCLUSION: 1) It would appear advisable to introduce a repeated routine screening for hypothyroidism in the group of low and very low birth-weight neonates, as this permits the identification of cases with raised values requiring verification. 2) In addition, thanks to the repeated screening we avoid false negative pitfalls in low and very low birth-weight neonates, i.e. primary congenital and transient hypothyroidism.