Search results for "hypothyroidism"
showing 10 items of 80 documents
Goitrous Congenital Hypothyroidism and Hearing Impairment Associated with Mutations in the TPO and SLC26A4/PDS Genes
2006
Abstract Context: Pendred syndrome (PS) and thyroid peroxidase (TPO) deficiency are autosomal-recessive disorders that result in thyroid dyshormonogenesis. They share congenital hypothyroidism, goiter, and an iodide organification defect as common features. Whereas the hallmark of PS is sensorineural deafness, other forms of congenital hypothyroidism may also lead to hearing impairment. Therefore, a definite diagnosis may be difficult and require molecular genetic analyses. Case Report: The propositus presented at birth with primary hypothyroidism and goiter. He also had congenital bilateral moderate hearing loss, and PS was suspected. Methods: We sequenced the SLC26A4/PDS and TPO genes in …
Hypothyroidism in patients treated with radiotherapy for head and neck carcinoma: standardised long-term follow-up study
2016
AbstractObjective:Hypothyroidism is a common complication when radiotherapy is part of the treatment for head and neck tumours. This study aimed to show the incidence of hypothyroidism and possible risk factors in these patients.Methods:Factors related to the population, tumour, treatment and occurrence of hypothyroidism were analysed in 241 patients diagnosed with head and neck carcinoma.Results:Approximately 53 per cent of patients were diagnosed with radiation-induced hypothyroidism. Its occurrence was related to: tumour location, laryngeal surgery type, neck dissection type, post-operative complications, cervical radiotherapy and radiotherapy unit type (linear particle accelerator or te…
Pseudodominant inheritance of goitrous congenital hypothyroidism caused by TPO mutations: molecular and in silico studies.
2007
CONTEXT AND OBJECTIVE: Most cases of goitrous congenital hypothyroidism (CH) from thyroid dyshormonogenesis 1) follow a recessive mode of inheritance and 2) are due to mutations in the thyroid peroxidase gene (TPO). We report the genetic mechanism underlying the apparently dominant inheritance of goitrous CH in a nonconsanguineous family of French Canadian origin. DESIGN, SETTING, AND PARTICIPANTS: Two brothers identified by newborn TSH screening had severe hypothyroidism and a goiter with increased (99m)Tc uptake. The mother was euthyroid, but the father and two paternal uncles had also been diagnosed with goitrous CH. After having excluded PAX8 gene mutations, we hypothesized that the und…
Reduction of mortality rate in premature infants by substitution of thyroid hormones.
1981
Our previous examinations had shown that 9 of 13 premature infants with severe respiratory distress had hypothyroid T4-values. On the basis of these results a prospective study was initiated. Every second neonate born after less than 37 weeks gestation or weighing less than 2200 g and admitted to our intensive care unit since Janary 1979 received a prophylactic dose of 25 μg l-Thyroxine and 5 μg Tri-iodothyronine daily. Five of the patients inadvertently did not receive the drug and were included in the non-treated group which thus numbered 55. Both groups were nearly identical with regard to gestational age, birth weight and Apgar score. In the treated group of 45 infants three (=6.6%) die…
Neonatal screening for congenital hypothyroidism in an Italian Centre: a 5-years real-life retrospective study
2021
Abstract Introduction Congenital hypothyroidism is an endocrine disease with a significant incidence in the general population (1:2000–1:3000 newborns in Italy) and a different geographical distribution, partially explained by endemic iodine deficiency, genetic traits and autoimmune thyroid diseases. Objectives Aims of this study are: to evaluate the incidence of positive neonatal blood spot screening for CH in western Sicily, identified by the screening centre of the Children Hospital “G. Di Cristina”, ARNAS, Palermo; to evaluate the impact of a lower TSH cutoff in the neonatal blood spot screening for CH. Materials and methods The TSH threshold of the neonatal screening was established as…
Mutations in the PDS Gene in German Families with Pendred’s Syndrome: V138F Is a Founder Mutation
2003
Pendred's syndrome, an autosomal-recessive condition characterized by congenital sensorineural hearing loss and goiter, is caused by mutations in the PDS gene. Located on chromosome 7q22-q31, it encodes a chloride-iodide transporter expressed in the thyroid, inner ear, and kidney. We investigated the PDS gene of six affected individuals from four unrelated families with Pendred's syndrome by direct sequencing. PDS mutations were identified in homozygous or compound heterozygous state in all six cases. A homozygous missense mutation leading to the amino acid substitution S133T was detected in a family of Turkish origin. The mutations found in the other affected individuals, who originate fro…
Effect of Thyroid Hormones on Urea Biosynthesis and Related Processes in Rat Liver*
1988
The results of the few studies on the effect of the thyroid status on nitrogen metabolism have been inconclusive and/or contradictory. In an attempt to elucidate this important relationship, we have studied the effect of experimental hypo- and hyperthyroidism on urea biosynthesis and related processes. We have found that the capacity of the liver to synthesize urea was increased in hypothyroid rats, as were the activities of the urea cycle enzymes; there were also changes in the activities of some related enzymes and in the levels of intermediates and amino acids. Isolated hepatocytes from these rats showed an increased capacity for urea synthesis. In hyperthyroid rats the picture was more …
Thyroid hormone deficiency disrupts rat eye neurodevelopment
2010
Clinical and experimental studies have highlighted the role played by thyroid hormones (TH) in neural and neuro-sensorial development. However, knowledge on TH mechanisms on the developing visual system is still incomplete. To uncover TH actions on the eyes and vision we carried out a microscopical study on the role of TH in the developing retina and optic nerve, in a rat model of controlled TH deficiency (THD). Morphometric and stereological analyses of the retina and optic nerve showed a reduction in the volume of the eye (p<0.001) and optic nerve cross-sectional area (p<0.001), and thinning of the retinal layers (p<0.001). Glial development and myelination was significantly delayed in th…
A Novel Deletion in the Thyrotropin Beta-Subunit Gene Identified by Array Comparative Genomic Hybridization Analysis Causes Central Congenital Hypoth…
2014
<b><i>Background:</i></b> Isolated central congenital hypothyroidism (ICCH) is rare but important. Most ICCH patients are diagnosed later, which results in severe growth failure and intellectual disability. <b><i>Objective:</i></b> We describe a boy with ICCH due to a large homozygous <i>TSHβ </i>gene deletion. <b><i>Results:</i></b> A 51-day-old male Turkish infant, whose parents were first cousins, was admitted for evaluation of prolonged jaundice. His clinical appearance was compatible with hypothyroidism. Venous thyrotropin (TSH) was undetectably low, with a subsequent low free T4 and a low free T3, sugg…
Abnormal thyroid hormones and non-thyroidal illness syndrome in obstructive sleep apnea, and effects of CPAP treatment
2016
Objective In obstructive sleep apnea (OSA), while both hypothyroidism and hyperthyroidism have been studied, the occurrence of non-thyroidal illness syndrome (NTIS) (normal thyroid stimulating hormone [TSH] with low triiodotironine) has not been investigated. We explored the occurrence of NTIS in patients with moderate to severe OSA and its relationship to the severity of nocturnal respiratory disorders. We also studied the occurrence of subclinical hypothyroidism (SH, ie, high TSH with normal thyroxine) in OSA and changes in circulating TSH, free triiodotironine (fT3) and free thyroxine (fT4) after CPAP treatment. Methods After a nocturnal respiratory polysomnography, 125 consecutive patie…