Achieving diagnostic certainty in resource-limited settings.
Abstract
Disorders of sex development are complex disorders with atypical chromosomal, gonadal or anatomical sex. Decision making in relation to sex assignment has been perceived as extremely disturbing and difficult for families and healthcare professionals. This is mainly due to a general paucity of information about the condition, lack of advanced diagnostic settings, and an exaggerated feeling of stigma and shame associated with genital abnormalities. Lack of accurate healthcare information and reporting results in poor knowledge about the exact incidence and impact of these disorders in resource-poor ...
Source: Endocrine Development - September 25, 2014 Category: Endocrinology Authors: Raza J, Mazen I Tags: Endocr Dev Source Type: research
Global Application of Disorders of Sex Development-Related Electronic Resources: e-Learning, e-Consultation and e-Information Sharing.
Abstract
The past 20 years have seen proliferation of electronic (e) resources that promote improved understanding of disorders of sex development (DSD): e-learning for physicians and trainees, e-consultation between clinicians, and e-information for families and affected individuals. Recent e-learning advances have emerged from the European Society for Pediatric Endocrinology's online learning portal for current physicians and trainees. Developed with attention to developing clinical competencies incorporating learning theory, and presenting material that represents international best practice, this e-lea...
Source: Endocrine Development - September 25, 2014 Category: Endocrinology Authors: Muscarella M, Kranenburg-van Koppen L, Grijpink-van den Biggelaar K, Drop SL Tags: Endocr Dev Source Type: research
International networks for supporting research and clinical care in the field of disorders of sex development.
Abstract
Differences or disorders of sex development (DSD) are a wide range of relatively rare conditions with diverse pathophysiology that most often present in the newborn or the adolescent. Given their rarity and the need for input from a range of clinical disciplines, the management of the child with a complex form of DSD may be quite complicated, and the situation is worsened by a lack of evidence for many diagnostic and interventional procedures that are undertaken. It is, therefore, not surprising that there will be variation in the management as well as the outcome of patients with this group of co...
Source: Endocrine Development - September 25, 2014 Category: Endocrinology Authors: Ahmed SF, Bryce J, Hiort O Tags: Endocr Dev Source Type: research
Evolution, child development and the thyroid: a phylogenetic and ontogenetic introduction to normal thyroid function.
Abstract
Congenital thyroid diseases can be explained in the context of the individual ontogenetic development; however, they can also be mirrored in the perspective of the phylogenetic evolution of the thyroid hormone system. The unique feature of the system, e.g. the generation of iodinated tyrosine derivatives by specialized enzymes that are frequently disrupted by mutations in congenital hypothyroidism, occurred very early in plant evolution and can still be demonstrated in algae today. All other components like the thyroid hormone receptors (TRs), the transporter molecules, the regulation by thyroid-s...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Krude H Tags: Endocr Dev Source Type: research
Human fetal thyroid function.
Abstract
The early steps of thyroid development that lead to its function in the human fetus and subsequently the further maturation that allows the human fetus to secrete thyroxine (T4) in a significant amount are reviewed here. We underline the importance of the transfer of T4 from the pregnant woman to her fetus, which contributes at all stages of the pregnancy to fetal thyroid function and development. In the first trimester of pregnancy, the temporal and structural correlation of thyroid hormone synthesis with folliculogenesis supported the concept that structural and functional maturations are closel...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Polak M Tags: Endocr Dev Source Type: research
The role of thyroid hormones for brain development and cognitive function.
Abstract
Through its actions on regulatory genes that form, grow and sculpt the brain, thyroid hormone (TH) is essential for human brain development. Although much of what we know about these effects is based on research with rodents, recent studies of children exposed to TH insufficiencies during critical stages of early development provide preliminary evidence on how and when the human brain needs TH. This paper reviews some of the major studies from both the rodent research and research on offspring of women with hypothyroidism during pregnancy and children with congenital hypothyroidism (CH) who were a...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Rovet JF Tags: Endocr Dev Source Type: research
Neonatal screening for congenital hypothyroidism.
Abstract
The possibility of measuring thyroid hormones from blood dried on filter paper opened the way to identifying neonates with congenital hypothyroidism (CH) already in the first days of life. Consequently the early initiation of adequate replacement therapy opened the way to an effective prevention of mental retardation. Timely and complete specimen collection, transport logistics, rapid analysis and communication of results are key points for the organization of a CH newborn screening program. Close collaboration between laboratory and treating specialists is necessary to ensure an adequate treatmen...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Torresani T Tags: Endocr Dev Source Type: research
Diagnosis, treatment and outcome of congenital hypothyroidism.
Abstract
Screening for a disease begins a process that should lead to confirmation of the diagnosis, establishment of the etiology, optimal treatment and documentation of outcome. In newborns referred for an elevated thyroid-stimulating hormone (TSH) level on the screening specimen, a detailed family and personal history should be obtained, and a careful clinical examination should be performed. Hypothyroidism should be confirmed by measuring serum TSH and thyroxine (T4) and the underlying etiology established by sodium pertechnetate scintigraphy. Treatment should be started promptly with an adequate dose ...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Van Vliet G, Deladoëy J Tags: Endocr Dev Source Type: research
Clinical genetics of congenital hypothyroidism.
Abstract
Congenital hypothyroidism (CH) is a state of insufficient thyroid hormone supply to the organism, starting in utero. Two forms of permanent primary or thyroidal CH are known. Thyroid dysgenesis (TD) describes a spectrum of defects of thyroid organogenesis. Five monogenetic forms due to mutations in TSHR, PAX8, NKX2-1, FOXE1 and NKX2-5 have been identified so far. Thyroid dyshormonogenesis comprises defects at every step of thyroid hormone synthesis. Mutations in 7 genes are well described causing iodine transport defect (SLC5A5), iodine organification defect (TPO, DUOX2, DUOXA2, SLC26A4), thyroglo...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Szinnai G Tags: Endocr Dev Source Type: research
Central hypothyroidism in children.
Abstract
Central congenital hypothyroidism (CCH) is an underdiagnosed disorder poorly described in childhood and adolescence. Congenital defects in thyroid-stimulating hormone (TSH) synthesis, secretion or bioactivity may lead to a state of 'regulatory' hypothyroidism expressed through aberrantly low or normal TSH levels and low thyroxine (T4), a hormonal pattern undetectable by TSH-based neonatal screening programs for congenital hypothyroidism (CH) implemented in most countries worldwide. CCH is more prevalent than previously thought, reaching 1 in 16,000 neonates in countries consistently identifying CC...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: García M, Fernández A, Moreno JC Tags: Endocr Dev Source Type: research
Thyroid hormone cell membrane transport defect.
Abstract
In the last few years, many studies have pinpointed the crucial role of thyroid hormone (TH) transporters for TH action in human target cells. The importance was better documented by the phenotype observed in patients harboring mutations of the monocarboxylate transporter 8 (MCT8) gene immediately linked to Allan-Herndon-Dudley syndrome, in which severe neurological findings are associated with abnormal TH levels. The hereditary pattern of MCT8 mutations is X chromosome linked, with males presenting a homogeneous neurological psychomotor phenotype and mental retardation associated with low serum t...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Ramos HE Tags: Endocr Dev Source Type: research
Resistance to thyroid hormone.
Abstract
Resistance to thyroid hormone (RTH) or thyroid hormone action defect (THAD) is the most frequent form of syndromes of reduced sensitivity to thyroid hormone. It is characterized by variable tissue hyposensitivity to thyroid hormone. RTHβ (formerly only RTH) is caused by mutations in the thyroid hormone receptor β gene (THRB). The clinical phenotype reflects the dysbalance between resistance of tissues predominantly expressing the thyroid hormone receptor β-isoforms 1 and 2 and the overstimulation of tissues mainly expressing the thyroid hormone receptor α-isoform to thyroid hormones. The hallm...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Onigata K, Szinnai G Tags: Endocr Dev Source Type: research
Iodine deficiency in children.
Abstract
Iodine is an essential trace mineral, required for the production of thyroid hormone. Iodine deficiency may result in goiter, hypothyroidism, miscarriage, stillbirth, congenital anomalies, infant and neonatal mortality, and impaired growth. Adequate thyroid hormone is critically important for normal growth and neurodevelopment in fetal life, infancy and childhood. The population iodine status is most commonly assessed using median urinary iodine concentration values, but goiter prevalence (determined by palpation or by ultrasound), serum thyroglobulin levels, and neonatal thyroid-stimulating hormo...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Pearce EN Tags: Endocr Dev Source Type: research
Thyroid autoimmunity.
Abstract
Autoimmune thyroid disease (AITD) is a multifactorial disease in which autoimmunity against thyroid antigens develops against a particular genetic background facilitated by exposure to environmental factors. Immunogenicity of the major thyroid antigens thyroid peroxidase, thyroglobulin (TG) and thyrotropin receptor (TSHR) is increased by genetic polymorphisms, a high number of antigenic peptides available for binding to human leukocyte antigen (HLA), and a high degree of glycosylation. Antigens bound to HLA are presented by antigen-presenting cells to T cell receptors. Further interaction between ...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Wiersinga WM Tags: Endocr Dev Source Type: research
Clinical Aspects of Hashimoto's Thyroiditis.
Abstract
Hashimoto's thyroiditis (HT) is one of the commonest autoimmune endocrine diseases in the paediatric age group. It is considered a typical, organ-specific, autoimmune disease, characterized by autoimmune-mediated destruction of the thyroid gland. The diagnosis is suggested by a typical ultrasound pattern and by the presence of antithyroid antibodies. Attention must be taken with obese children as they may have an echographic pattern very similar to that observed in patients with HT, without being affected. HT is frequently associated with other autoimmune diseases such as alopecia, vitiligo, coeli...
Source: Endocrine Development - September 20, 2014 Category: Endocrinology Authors: Radetti G Tags: Endocr Dev Source Type: research
