Search results for " hypothyroidism"
showing 9 items of 49 documents
Developmental Abnormalities of the Thyroid
2010
Publisher Summary This chapter explores the abnormalities in the development of the thyroid gland during organogenesis referred to as thyroid dysgenesis. Permanent primary congenital hypothyroidism (CH) is mentioned to be the most common congenital endocrine disorder as estimated from systematic biochemical screening of newborns. The functional disorders of the thyroid gland are known as thyroid dyshormonogenesis and this disorder is typically inherited in an autosomal recessive manner and common in populations with a high degree of consanguinity. It briefly reviews the single gene disorders that cause CH from thyroid dysgenesis, and mutations that activate the thyrotropin receptor (TSH) re…
A New Mutation in the Promoter Region of the PAX8 Gene Causes True Congenital Hypothyroidism with Thyroid Hypoplasia in a Girl with Down's Syndrome
2014
Thyroid dysfunction is common in newborn infants with Down's syndrome (DS), but defects causing classic thyroid dysgenesis (TD) with permanent congenital hypothyroidism (CH) have not been described.We studied a girl with DS and CH who had a mutation in the promoter sequence of the PAX8 gene.A female infant was found to have trisomy 21 and CH, with a venous thyrotropin (TSH) of150 mU/L and a free thyroxine (fT4) of 15.1 pmol/L (day 12). Thyroid peroxidase antibodies and thyroglobulin antibodies were elevated. Scintigraphy showed normal uptake, but ultrasound identified a small gland with heterogenous echotexture and cystic changes. Sequence analysis of the PAX8 gene revealed a new heterozygo…
Motor problems in children with early-treated congenital hypothyroidism: A matter of failing cerebellar motor control?
1998
This study addresses the question of whether "clumsiness" in children with early treated Congenital Hypothyroidism (CH) might be attributable to cerebellar dysfunction. CH is known to affect rapid perinatal growth of the cerebellum. If this would affect the supposed motor timing function of the cerebellum this should be especially reflected by difficulty in producing fast aiming movements. An experiment was devised in which children made sequences of fast, goal directed movements in order to examine two aspects of fast voluntary movements that are known to be affected by cerebellar injury: dysmetria and dysdiadochokinesis. Three groups of children between the ages of 9 and ii participated: …
Congenital secondary hypothyroidism caused by exon skipping due to a homozygous donor splice site mutation in the TSHbeta-subunit gene.
2002
Isolated TSH deficiency as a cause for congenital hypothyroidism is relatively uncommon. Even more rare is the identification of mutations in the TSHβ gene, only four of which have been identified. We here report a 4-month-old girl with isolated TSH deficiency born to consanguineous parents. Sequencing of the TSHβ-subunit gene revealed a homozygous G to A transition at position +5 of the donor splice site of intron 2. TSHβ gene transcript could not be obtained from fibroblasts or white blood cells by illegitimate amplification. Thus, to investigate further the mechanism leading to TSH deficiency in this patient, we used an in vitro exon-trapping system. The mutation at position +5 of the do…
Goitrous congenital hypothyroidism in a twin pregnancy causing respiratory obstruction at birth: Implications for management
2006
We report a twin pregnancy complicated by fetal goitrous hypothyroidism secondary to dyshormonogenesis caused by thyroglobulin deficiency. Antenatal treatment with intra-amniotic thyroxine was considered but not performed, given the late gestational age at diagnosis and the multiple nature of the pregnancy. Both twins developed airway obstruction at delivery, requiring intubation and ventilation. We review the literature and describe the practical issues relating to the antenatal assessment and perinatal management of fetal goitre.
Transient hypothyroidism during lactation arrests myelination in the anterior commissure of rats. A magnetic resonance image and electron microscope …
2018
Thyroid hormone deficiency at early postnatal ages affects the cytoarchitecture and function of neocortical and telencephalic limbic areas, leading to impaired associative memory and in a wide spectrum of neurological and mental diseases. Neocortical areas project interhemispheric axons mostly through the corpus callosum and to a lesser extent through the anterior commissure (AC), while limbic areas mostly project through the AC and hippocampal commissures. Functional magnetic resonance data from children with late diagnosed congenital hypothyroidism and abnormal verbal memory processing, suggest altered ipsilateral and contralateral telencephalic connections. Gestational hypothyroidism aff…
Mutations in the NKX2.5 Gene and the PAX8 Promoter in a Girl with Thyroid Dysgenesis
2011
Screening of the known candidate genes involved in thyroid organogenesis has revealed mutations in a small subset of patients with congenital hypothyroidism due to thyroid dysgenesis (TD).We studied a girl with TD who had mutations in two transcription factors involved in thyroid development.Sequencing analysis of candidate genes involved in thyroid gland development revealed a new paternally inherited heterozygous mutation in the NKX2.5 gene (S265R) and a new maternally inherited heterozygous mutation in the PAX8 promoter region (-456CT). Both parents and a brother, who was also heterozygous for both mutations, were phenotypically normal. Immunofluorescence microscopy showed a correct nucl…
L'ESAME CAPILLAROSCOPICO ORALE: NUOVA METODICA DIAGNOSTICA
2005
The morphological-functional study of microcirculation is of fundamental importance; in fact, the microvascular bed is directly involved both in autoimmune etiopathogenesis pathologies, and in acute and chronic inflammatory etiopathogenesis pathologies. Oral capillaroscopy is a very stimulating method for studying microcirculation, because of the possibility of studying small vessels in vivo by means of a microscope. Today, it is becoming more reliable thanks to the improvement of the observation tools (photography, videomicroscopy).