High-resolution melting analysis (HRM) for mutational screening of Dnajc17 gene in patients affected by thyroid dysgenesis.

BACKGROUND: Congenital hypothyroidism is a frequent disease occurring with an incidence of about 1/1500 newborns/year. In about 75% of the cases, CH is caused by alterations in thyroid morphogenesis, defined "thyroid dysgenesis" (TD). TD is generally a sporadic disease but in about 5% of the cases a genetic origin has been demonstrated. Previous studies indicate that Dnajc17 as a candidate modifier gene for hypothyroidism, since it is expressed in the thyroid bud, interacts with NKX2.1 and PAX8 and it has been associated to the hypothyroid phenotype in mice carrying a single Nkx2.1 and Pax8 genes (double heterozygous knock-out). PURPOSE: The work evaluates the possible involvement of DNAJC17 in the pathogenesis of TD. METHODS: High-resolution DNA melting analysis (HRM) and direct sequencing have been used to screen for mutations in the DNAJC17 coding sequence in 89 patients with TD. RESULTS: Two mutations have been identified in the coding sequence of DNAJC17 gene, one in exon 5 (c.350A>C; rs79709714) and one in exon 9 (c.610G>C; rs117485355). The last one is a rare variant, while the rs79709714 is a polymorphism. Both are present in databases and the frequency of the alleles is not different between TD patients and controls. CONCLUSIONS: DNAJC17 mutations are not frequently present in patients with TD.

Pregnancy outcome in women treated with methimazole or propylthiouracil during pregnancy.

PURPOSE: Control of thyroid function in hyperthyroid women during pregnancy is based on antithyroid drugs (ATD) [propylthiouracil (PTU) and methimazole (MMI)]. While a teratogenic effect has been suggested for MMI and, more recently, for PTU, a clear demonstration is still lacking. Aim of this study was to assess the safety of ATD during pregnancy. METHODS: A total of 379 pregnancies were retrospectively recruited in eight Italian Departments of Endocrinology and divided in five groups: (1) MMI-treated and euthyroid throughout pregnancy (n = 89); (2) MMI-treated and hyperthyroid on at least two occasions (n = 35); (3) PTU-treated women and euthyroid throughout pregnancy (n = 32); (4) PTU-treated women and hyperthyroid on at least two occasions (n = 20); and (5) non-ATD-treated (n = 203). Data on maternal thyroid function, miscarriages, type of delivery, neonatal weight, length and TSH, perinatal complications and congenital malformation were analyzed. RESULTS: The gestational age at delivery, the rate of vaginal delivery, neonatal weight, length and neonatal TSH did not significantly differ among groups. In all groups, the rates of spontaneous miscarriage and of major congenital malformations were not higher than in the general population. No newborns were born with a phenotype similar to those described in the "MMI embryopathy". CONCLUSIONS: While a clear demonstration of a teratogenic effect of MMI is currently lacking, it seems reasonable to follow the current guidelines and advice for PTU treatment in hyperthyroid women during the first trimester of pregnancy. Further, large and prospective worldwide studies will be needed to fully clarify the issue of ATD safety during pregnancy.

The molecular causes of thyroid dysgenesis: a systematic review.

BACKGROUND: Congenital hypothyroidism (CH) is a frequent disease occurring with an incidence of about 1/2500 newborns/year. In 80-85% of the cases CH is caused by alterations in thyroid morphogenesis, generally indicated by the term "thyroid dysgenesis" (TD). TD is generally a sporadic disease, but in about 5% of the cases a genetic origin has been demonstrated. In these cases, mutations in genes playing a role during thyroid morphogenesis (NKX2-1, PAX8, FOXE1, NKX2-5, TSHR) have been reported. AIM: This work reviews the main steps of thyroid morphogenesis and all the genetic alterations associated with TD and published in the literature.

A mouse model for hereditary thyroid dysgenesis and cleft palate.

Alteration of thyroid gland morphogenesis (thyroid dysgenesis) is a frequent human malformation. Among the one in three to four thousand newborns in which congenital hypothyroidism is detected, 80% have either an ectopic, small and sublingual thyroid, or have no thyroid tissue. Most of these cases appear sporadically, although a few cases of recurring familial thyroid dysgenesis have been described. The lack of evidence for hereditary thyroid dysgenesis may be due to the severity of the hypothyroid phenotype. Neonatal screening and early thyroid hormone therapy have eliminated most of the clinical consequences of hypothyroidism such that the heritability of this condition may become apparent in the near future. We have recently cloned cDNA encoding a forkhead domain-containing transcription factor, TTF-2, and have located the position of the gene, designated Titf2, to mouse chromosome 4 (ref. 3). Titf2 is expressed in the developing thyroid, in most of the foregut endoderm and in craniopharyngeal ectoderm, including Rathke's pouch. Expression of Titf2 in thyroid cell precursors is down-regulated as they cease migration, suggesting that this factor is involved in the process of thyroid gland morphogenesis. Here we show that Titf2-null mutant mice exhibit cleft palate and either a sublingual or completely absent thyroid gland. Thus, mutation of Titf2-/- results in neonatal hypothyroidism that shows similarity to thyroid dysgenesis in humans.

PAX8 mutations associated with congenital hypothyroidism caused by thyroid dysgenesis.

Permanent congenital hypothyroidism (CH) is a common disease that occurs in 1 of 3,000-4,000 newborns. Except in rare cases due to hypothalamic or pituitary defects, CH is characterized by elevated levels of thyroid-stimulating hormone (TSH) resulting from reduced thyroid function. When thyroid hormone therapy is not initiated within the first two months of life, CH can cause severe neurological, mental and motor damage. In 80-85% of cases, CH is associated with and presumably is a consequence of thyroid dysgenesis (TD). In these cases, the thyroid gland can be absent (agenesis, 35-40%), ectopically located (30-45%) and/or severely reduced in size (hypoplasia, 5%). Familial cases of TD are rare, even though ectopic or absent thyroid has been occasionally observed in siblings. The pathogenesis of TD is still largely unknown. Although a genetic component has been suggested, mutations in the gene encoding the receptor for the thyroid-stimulating hormone (TSHR) have been identified in only two cases of TD with hypoplasia. We report mutations in the coding region of PAX8 in two sporadic patients and one familial case of TD. All three point mutations are located in the paired domain of PAX8 and result in severe reduction of the DNA-binding activity of this transcription factor. These genetic alterations implicate PAX8 in the pathogenesis of TD and in normal thyroid development.

SERS assisted sandwich immunoassay platforms for ultrasensitive and selective detection of human Thyroglobulin.

We developed an immunoassay platform for the detection of human Thyroglobulin (Tg) to be integrated with fine-needle aspiration biopsy for early detection of lymph node metastases in thyroid cancer patients. The sensing platform detects Tg by a sandwich immunoassay involving a self-assembled surface-enhanced Raman scattering (SERS) substrate assisted by functionalized gold nanoparticles that provide additional Raman signal amplification and improved molecular specificity. Specifically, the SERS-active substrates were functionalized with Tg Capture antibodies and fabricated either on-chip or on optical fiber tips by nanosphere lithography. Gold nanoparticles were functionalized with Detection antibodies and conjugated with 4-mercaptobenzoic acid, which serves as a Raman reporter. The sandwich assay platform was validated in the planar configuration and a detection limit as low as 7 pg/mL was successfully achieved. Careful morphological examination of the SERS substrates before and after Tg measurements further assessed the effective capture of nanoparticles and correlated the average nanoparticle coverage with the Tg concentration obtained by SERS measurements. The sandwich assay was successfully demonstrated on washout fluids of fine needle aspiration biopsies from cancer patients and confirmed the high specificity of the proposed methodology when complex biological matrices are considered. Finally, SERS optrodes were fabricated and successfully used to detect Tg concentration by applying the same bio-recognition strategy and Raman interrogation through an optical fiber. This opens the possibility of transferring the Tg detection approach to the optical fiber tip to develop point-of-care platforms that can be directly integrated into fine needle aspiration biopsies.

Screening for mutations in the ISL1 gene in patients with thyroid dysgenesis.

CONTEXT: Congenital hypothyroidism (CH) is a common endocrine disorder with an incidence of 1:3000- 4000 newborns. In 80-85% of cases, CH is caused by defects in thyroid organogenesis, resulting in absent, ectopically located, and/or severely reduced gland, all conditions indicated as "thyroid dysgenesis" (TD). A higher prevalence of congenital heart diseases has been documented in children with CH compared to the general population. This association suggests a possible pathogenic role of genes involved in both heart and thyroid development. Among these, it can be included Isl1, a transcription factor containing a LIM homeodomain that is expressed in both thyroid and heart during morphogenesis. OBJECTIVE: In the present study, we investigate the role of ISL1 in the pathogenesis of TD. SETTINGS AND PATIENTS: By single stranded conformational polymorphism, we screened for mutations the entire ISL1 coding sequence in 96 patients with TD and in 96 normal controls. RESULTS: No mutations have been found in patients and controls. CONCLUSION: Our data indicate that, despite the relevant role of ISL1 in thyroid and heart morphogenesis, mutations in its coding region are not associated with TD in our group of patients.

Mutations in TAZ/WWTR1, a co-activator of NKX2.1 and PAX8 are not a frequent cause of thyroid dysgenesis.

AIM: In 80-85% of cases, congenital hypothyroidism is associated with thyroid dysgenesis (TD), but only in a small percentage of cases mutations in thyroid transcription factors (NKX2.1, PAX8, FOXE1, and NKX2.5) have been associated with the disease. Several studies demonstrated that the activity of the transcription factors can be modulated by the interaction with other proteins, such as coactivators and co-repressors, and TAZ (transcriptional co-activator with PDZ-binding motif or WWTR1) is a co-activator interacting with both NKX2.1 and PAX8. In the present study we investigate the role of TAZ in the pathogenesis of TD. MATERIAL AND METHODS: By Single Stranded Conformational Polymorphism, we screened the entire TAZ coding sequence for mutations in 96 patients with TD and in 96 normal controls. RESULTS: No mutations were found in patients and controls, but we found several polymorphisms in both groups. No significant differences could be demonstrated in the prevalence of the mutations between patients and controls. CONCLUSIONS: Our data indicate that TAZ mutations are not a cause of TD in the series of patients studied.

Molecular genetics of congenital hypothyroidism.

Congenital thyroid gland defects - resulting in reduced production of the hormones triiodothyronine (T3) and thyroxine (T4) - can be a consequence of either reduced or absent thyroid tissue (thyroid dysgenesis) or, less frequently, of impairment in the biochemical mechanisms responsible for hormone biosynthesis (thyroid dyshormonogenesis). Recent studies have revealed how mutations in the genes encoding either transcription factors or the thyroid stimulating hormone receptor cause, in humans or in mouse models, thyroid dysgenesis. This demonstrates, for the first time, the heritability of this condition. New genes responsible for thyroid dyshormonogenesis have also been discovered.

Integrin expression in thyroid cells from normal glands and nodular goiters.

To assess the expression of the very late antigens family of the integrin superfamily in normal and diseased thyroid glands, tissue specimens were digested to a single cell suspension and analyzed by flow cytometry with antibodies against the common beta 1 chain and the six alpha chains known to be associated to beta 1. In multinodular goiters, two cell populations were recognized. The thyroglobulin containing follicular cell population, represented the majority of cells; a minor population was composed of leukocytes. In normal glands, more than 97% of follicular cells expressed the beta 1 chain, associated with high levels of alpha 3 and very low levels of alpha 1, alpha 5, and alpha 6. The remaining cells (< 3%) expressed the beta 1 chain with a 10-fold higher intensity, associated with relatively high levels of alpha 1, alpha 5, and alpha 6, in addition to alpha 3. This small subset was much more represented in multinodular goiters, where it ranged from 10-60% of the total follicular cell population. Immunofluorescence on tissue sections showed that very late antigens were mostly located on the basal cell membrane and that in multinodular goiters cells expressing the alpha 1, alpha 5, and alpha 6 chains occurred in clusters.

Thyroid function tests and characterization of thyroxine-binding globulin in the carbohydrate-deficient glycoprotein syndrome type I.

Carbohydrate-deficient glycoprotein (CDG) syndrome is a newly recognized hereditary disorder that presents with psychomotor retardation, cerebellar ataxia, peripheral sensorimotor neuropathy, and, variably, skeletal abnormalities, lipodystrophy, and retinitis pigmentosa. These abnormalities appear to be produced by a defect that causes reduced carbohydrate content in glycoproteins. We studied seven patients with CDG type I belonging to five unrelated families. The concentration of serum TBG, a glycoprotein of hepatic origin, was measured by RIA and T4 saturation and was found to be below the normal range in three of the seven patients and normal in four of them. More than half of the total serum TBG had reduced sialic acid content and localized on isoelectric focusing (IEF) as two prominent bands cathodal to the three major bands of normal TBG. The latter two bands are responsible for the characteristic IEF pattern or CDG syndrome. TBG in patients with CDG had immunoreactivity indistinguishable from that of normal TBG and had normal affinity for T4, T3, and rT3. Serum total T4, T3, and rT3 were below the normal range in seven, five, and seven patients, respectively. The free T4 index was also below normal in four patients, but the free T4 concentration, measured by equilibrium dialysis at low dilution, and serum TSH were in the midnormal range. The serum total T4 and rT3 levels were disproportionately reduced relative to the serum TBG concentration and compared to the concentrations of these iodothyronines in matched subjects with inherited partial TBG deficiency. Chronic illness cannot explain these changes, because, contrary to patients with nonthyroidal illness, those with CDG had significantly higher serum total T3/T4 and lower rT3/T4 ratios. It is concluded that IEF of TBG is a rapid and simple method for the diagnosis of CDG type I and that the abnormal pattern can be detected as early as 5 days postpartum. Patients with CDG are chemically euthyroid, and it is postulated that the reduction in serum iodothyronine concentrations beyond that explained on the basis of low TBG levels may be due to the interference with binding to TBG by an unidentified substance.

Search for abnormalities of nuclear corepressors, coactivators, and a coregulator in families with resistance to thyroid hormone without mutations in thyroid hormone receptor beta or alpha genes.

The syndrome of resistance to thyroid hormone (RTH) is characterized by decreased tissue responsiveness to thyroid hormones. Inheritance is usually autosomal dominant due to mutations in the ligand-binding domain or adjacent hinge region of the thyroid hormone receptor beta (TRbeta) gene. Six of 65 families with the RTH phenotype studied in our laboratory had normal TRbeta1 and TRbeta2 gene sequences. Their clinical characteristics were not different from those of subjects with TRbeta gene mutations. Four of the 6 families were amenable to linkage analysis, and TRalpha involvement was excluded. Candidate genes were then evaluated for their possible involvement in the RTH phenotype in these 4 families: 2 coactivators [NCoA-1 (SRC-1) and NCoA-3 (AIB-1)], 2 corepressors (NCoR and SMRT), and a coregulator (RXRgamma). DNA was obtained from 8 affected subjects and 41 of 45 living first degree relatives. In 2 of the 4 families, the mode of inheritance could be determined by pedigree analysis and was found to be autosomal dominant. Linkage analyses were performed using polymorphic markers near or within the 5 candidate genes. When analyses were not informative or linkage could not be excluded, direct sequencing of the genes in question was performed. Involvement of NCoA-1 was excluded in all four families assuming autosomal dominant inheritance. Roles for NCoR, SMRT, and NCoA-3 were excluded in three and a role for RXRgamma was excluded in two of the four families. However, if the two families without proven dominant mode of inheritance were compound heterozygous, only the involvement of NCoA-1 could be excluded in both. Roles for NCoR, SMRT, and RXRgamma were excluded in one of these two families. Thus, NCoA-1 and RXRgamma genes were not found to be the cause of RTH in subjects without TR gene mutations even though the absence of NCoA-1 and RXRgamma is the cause of RTH in mice. Involvement of other candidate genes in the mediation of thyroid hormone action as well as intracellular hormone transport needs to be explored in these families with non-TRbeta, TRalpha RTH.

Orbital scintigraphy with [111In-diethylenetriamine pentaacetic acid-D-phe1]-octreotide predicts the clinical response to corticosteroid therapy in patients with Graves' ophthalmopathy.

Corticosteroid treatment is successfully used in Graves' ophthalmopathy, and its effect varies according to the phase of the disease. The infiltration of the orbit by activated lymphocytes may explain the effectiveness of corticosteroid therapy. Scintigraphy with [111In-DTPA-D-Phe1]-octreotide was recently used to reveal the presence of activated lymphocytes in foci of autoimmune diseases, because elevated amounts of somatostatin receptors are expressed in the surface of these cells. The aim of the current study was to evaluate whether the degree of orbital [111In-DTPA-D-Phe1]-octreotide uptake is able to predict the response to corticosteroid therapy in patients with Graves' ophthalmopathy. Ten patients with Graves' ophthalmopathy entered the study. In all patients scintigraphy was performed, and subsequently, corticosteroid therapy (methylprednisolone, 1 g i.v. for 2 consecutive days a week for 6 weeks) was given. Clinical activity of Graves' ophthalmopathy was evaluated before and after treatment by calculating the ophthalmopathy index (OI). Planar and single photon emission computed tomography (SPECT) images of the head were obtained 24 h after the i.v. injection of 120-190 MBq of [111In-DTPA-D-Phe1]-octreotide. Radioligand uptake within each orbit (O) and brain (B) was measured using the region of interests (ROI) method and the O-to-B ratio was determined. According to the O-to-B ratio, the images were classified using the following three points score: 0 = O-to-B ratio < or =1; 1 = O-to-B ratio between 1 and 2.5; 2 = O-to-B ratio > or =2.5. The value of OI, measured before and after corticosteroid treatment, was correlated to the scintigraphic score. A significant change of OI was observed between posttreatment and pretreatment evaluation both in orbits with score 2 (OI: 15.4 +/- 1.5 vs. 9.6 +/- 0.5, P < 0.005) and in those with score 1 or 0 (OI: 12.9 +/- 1.5 vs. 11.5 +/- 1.4, P < 0.05) at the scintigraphy. However, when the OI was calculated excluding the changes in the soft tissue, which generally occur in all patients independently from the phase of the disease, a significant change of OI was observed only in the orbits with score 2 (OI: 12.9 +/- 1.3 vs. 8.3 +/- 0.5, P < 0.01) but not in those with score 0 or 1 (OI: 11.2 +/- 1.3 vs. 10.4 +/- 1.3). In particular, 6 weeks after corticosteroid treatment, the patients with orbital score 2 at the scintigraphy had a significant improvement of soft tissue changes, proptosis, lagophthalmos, extraocular muscle movements impairment, and diplopia, whereas patients with score 0 or 1 had only a significant improvement of the soft tissue inflammation. In conclusion, the current preliminary data suggested that [111In-DTPA-D-Phe1]-octreotide scintigraphy is able to predict the clinical response to corticosteroid treatment in patients with Graves' ophthalmopathy, and may be considered an useful approach to select the patients for the proper treatment.

Five new families with resistance to thyroid hormone not caused by mutations in the thyroid hormone receptor beta gene.

Resistance to thyroid hormone (RTH) is a syndrome of variable tissue hyposensitivity to TH. In 191 families, the RTH phenotype has been linked to mutations located in the ligand-binding or hinge domains of the TH receptor (TR) beta gene. The defective TRbeta molecules interfere with the function of the normal TRs to produce dominantly inherited RTH. Of the 65 families with RTH studied in our laboratory, 59 had mutations in the mutagenic region of the TRbeta gene that encompasses exons 7-10. Isolation of a TRbeta PAC (P1 derived artificial chromosome) clone provided the intronic sequences necessary to amplify and sequence the entire TRbeta gene from genomic DNA. Not a single nucleotide substitution, deletion, or insertion was found in all coding and noncoding TRbeta1- and TRbeta2-specific and common exons of the five families with RTH reported herein. Furthermore, linkage analysis using polymorphic markers excluded involvement of the TRbeta and TRalpha genes in two and three of the five families, respectively. The phenotype of RTH in patients without TRbeta gene defects was not different from that in patients with RTH due to TRbeta gene mutations in terms of clinical presentation and reduced responsiveness of the pituitary and peripheral tissues to TH. However, the degree of thyrotroph hyposensitivity to TH appeared to be among the more severe, similar to that of patients with mutant TRbetas that have more than 50-fold reduction of T3 binding affinity and strong dominant negative effect. In these five families and another with non-TRalpha/non-TRbeta RTH, previously identified in our laboratory, evidence for dominant inheritance was secured in two families, and the appearance of a new defect or recessive inheritance was found in the remaining four families. RTH without a structural TRbeta defect occurs in about 10% of families expressing the classic phenotype of TH hyposensitivity, and TRbeta and TRalpha gene involvement has been excluded in 5%. We postulate that a cofactor that interacts with TR is potentially responsible for the manifestation of RTH in these families. As affected subjects are not infertile, the high prevalence of putative neomutations and the low rate of transmission in this non-TR form of RTH may be due to reduced survival of embryos harboring the defect.

Cloning, chromosomal localization and identification of polymorphisms in the human thyroid transcription factor 2 gene (TITF2).

The human gene encoding the thyroid transcription factor 2 (TTF-2) was cloned and mapped to human chromosome 9q22. Three polymorphisms were identified in the gene by SSCP and direct sequencing: two consist of a third base substitution in the triplet encoding Leu129 and Ser273, and the third is an alanine stretch that varies from 12 to 17 residues. TTF-2 plays a critical role during thyroid morphogenesis in mice, and in man the TITF2 gene is associated with congenital hypothyroidism and cleft palate with thyroid dysgenesis. The polymorphisms identified in this study can be used as markers to study the role of the TITF2 gene in other cases of thyroid dysgenesis, especially in familial cases.

Thyroid function and effect of aging in combined hetero/homozygous mice deficient in thyroid hormone receptors alpha and beta genes.

The maintenance of thyroid hormone (TH) homeostasis is dependent on the synthesis and secretion of TH regulated by TSH. This is achieved, in turn, by the negative feedback of TH on TSH secretion and synthesis, which requires the interaction with TH receptors (TRs). Derived by alternative splicing of two gene transcription products, three TRs (TRbeta1, TRbeta2 and TRalpha1) interact with TH while another, TRalpha2, binds to DNA but not to TH. In this study we compare the results of thyroid function tests in mice with deletions of the TRalpha and TRbeta genes alone and present novel data on mice that are double homozygous and combined heterozygous. Homozygous deletions of both the TRalpha and TRbeta in the same mouse (TRalphao/o; TRbeta-/-) resulted in serum TSH values only slightly lower than those in athyreotic, Pax8 knockout mice. Whereas the absence of TRalpha alone does not cause resistance to TH, the absence of TRbeta in the presence of TRalpha results in a 205, 169, 544% increase in serum thyroxine (T(4)), triiodothyronine (T(3)) and TSH concentrations respectively. However, in the absence of TRbeta, loss of one TRalpha allele can worsen the resistance to TH with a 243 and 307% increase in T(4) and T(3) respectively. Similarly, while the heterozygous mouse with a single TRbeta allele shows no alteration in thyroid function, the concomitant deletion of TRalpha brings about mild but significant resistance to TH. Furthermore, the severity of the resistance to TH was noted to decrease with age in parallel with the decrease in serum free T(4) values also seen in wild-type mice. These results demonstrate that (1) unliganded TRalpha or TRbeta are not absolutely necessary for the upregulation of TSH; (2) TRbeta but not TRalpha is sufficient for TH-mediated downregulation of TSH; and (3) TRalpha may partially substitute for TRbeta in mediating a partial TH-dependent TSH suppression.

Mutations in the gene encoding thyroid transcription factor-1 (TTF-1) are not a frequent cause of congenital hypothyroidism (CH) with thyroid dysgenesis.

Permanent congenital hypothyroidism (CH) has an incidence of 1/3000-4000 newborns and is among the most frequent cause of mental retardation and neurological alterations in children. In 80% to 85% of cases CH is associated with thyroid dysgenesis. A group of 61 patients with CH (22 with agenesis, 18 with ectopy, 1 with hypoplasia, and 20 cases with CH without thyroid enlargement but not further characterized) and 30 normal subjects were examined for the presence of mutations in the gene encoding the thyroid transcription factor 1 (TTF-1). The coding-region of the TTF-1 gene was analyzed in all cases by the single stranded conformational polymorphism (SSCP) and no mutations were detected. Direct sequencing also carried out in patients with thyroid agenesis confirmed the absence of mutations or polymorphisms in the TTF-1 gene. The absence of mutations in the TTF-1 gene in our samples indicates that the mutations in the TTF-1 gene are not a frequent cause of CH.

[Endemic goiter: clinical picture and evolution]. / Gozzo endemico: quadro clinico ed evoluzione.

The goiter is the most frequent clinical manifestation of the nutritional deficiency of iodine. If present in more than 5% of the general population or more than 10% of the children in school of a defined geographic area, goiter is defined endemic. Endemic goiter is an adaptive disease produced by the persistent stimulation of the thyroid gland as consequence of the thyrotropin increased secretion due to the iodine deficiency. If iodine deficiency is severe or persistent, other manifestations can be observed in the clinical picture of the iodine deficiency disorders (IDD), such as cretinism. In general goiter is not associated to other manifestations during the initial state of the disease, but nodular and toxic evolution are frequent complication of long standing disease.

[Widespread endemic goiter and iodine deficiency in the province of Avellino]. / Diffusione del gozzo endemico e della carenza iodica in provincia di Avellino.

1352 schoolchildren between 6-14 years old (699 males and 653 females) and 943 adults (176 males and 767 females) from eight villages of the province of Avellino were studied. All subjects were examined for thyroid size by at least two expert examiners. In most of them urine samples were collected for iodine determinations. 387 schoolchildren and 161 adults from Flumeri and Villanova were evaluated by thyroid echography. The prevalence of goiter was from 23.5 to 52.2% and the median urinary iodine excretion was from 42.3 to 66.2 micrograms/l in schoolchildren. In adults the prevalence of goiter was from 41.2 to 86.7% and the median urinary iodine excretion was from 37.1 to 53.7 micrograms/l. Our data showed a degree of iodine deficiency from low to moderate. The echography permitted to point out a greater prevalence of nodules than the thyroid palpation.