Prevalence of Congenital Hypothyroidism in Isfahan, Iran: Results of a Survey on 20,000 Neonates

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Aims: To evaluate the prevalence of congenital hypothyroidism (CH) in a screening program performed for the first time in Isfahan, Iran. Methods: From May 2002 to December 2002, T<sub>4</sub> and TSH serum concentrations of 20,000 3- to 7-day-old newborns, born in all 17 hospitals of the city, were measured by radioimmunoassay and immunoradiometric assay, respectively. The newborns with abnormal screening results (TSH >20 mIU/l, T<sub>4</sub> <6.5 µg/dl and based on the weight) were re-examined. Results: Of 531 recalled subjects (recall rate 2.6%), 54 were confirmed to be hypothyroid, showing a prevalence of 1:370 for CH. Conclusion: Considering the high frequency of CH, the necessity of implementing a routine screening program in the healthcare system of Isfahan Province is emphasized.

Related collections

Most cited references 21

Record: found
Abstract: found
Article: not found

Timing of vulnerability of the brain to iodine deficiency in endemic cretinism.

K. O’Donnell, Lei Zhang, G Robert Delong … (1994)

Endemic cretinism, caused by severe iodine deficiency during pregnancy, is the world's most common preventable cause of mental retardation. It can be prevented by iodine treatment before conception, but whether it can be prevented or ameliorated by treatment during pregnancy or after delivery is not known. In a severely iodine-deficient area of the Xinjiang region of China, we systematically administered iodine to groups of children from birth to three years of age (n = 689) and women at each trimester of pregnancy (n = 295); we then followed the treated children and the babies born to the treated women for two years. We used three independent measures of neural development: the results of the neurologic examination, the head circumference (which correlates with brain weight in the first postnatal year), and indexes of cognitive and motor development. Untreated children one to three years of age, who were studied when first seen, served as control subjects. The prevalence of moderate or severe neurologic abnormalities among the 120 infants whose mothers received iodine in the first or second trimester was 2 percent, as compared with 9 percent among the 752 infants who received iodine during the third trimester (through the treatment of their mothers) or after birth (P = 0.008). The prevalence of microcephaly (defined as a head circumference more than 3 SD below U.S. norms) decreased from 27 percent in the untreated children to 11 percent in the treated children (P = 0.006), and the mean (+/- SD) developmental quotient at two years of age increased (90 +/- 14, vs. 75 +/- 18 in the untreated children; P < 0.001). Treatment in the third trimester of pregnancy or after delivery did not improve neurologic status, but head growth and developmental quotients improved slightly. Treatment during the first trimester, which was technically problematic, improved the neurologic outcome. Up to the end of the second trimester, iodine treatment protects the fetal brain from the effects of iodine deficiency. Treatment later in pregnancy or after delivery may improve brain growth and developmental achievement slightly, but it does not improve neurologic status.

0 comments Cited 65 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Applications of a new chemiluminometric thyrotropin assay to subnormal measurement.

Dhyanesh Patel, Keith Vom Eigen, Neil D. Gray … (1990)

A new immunochemiluminometric TSH assay (ICMA) was shown to offer improved analytical (+2 SD of zero) and functional (20% interassay coefficient of variation) sensitivity [0.003 vs 0.045 +/- 0.005 (+/- SE; range, 0.01-0.07); 0.018 vs. 0.23 +/- 0.02 (range, 0.10-0.35, mU/L); analytical vs. functional sensitivity limit for the ICMA vs. 10 other TSH immunometric assays, respectively]. The ICMA was used to study the physiological relationship between serum TSH and free T4 [as reflected by free T4 index (FT4I)] values at both steady state and 14 days after acute pharmacological T4 administration (3 mg oral T4 load plus 0.3 mg daily). At steady state, an inverse log/linear relationship was found between serum TSH and FT4I values (log TSH = 2.56 - 0.022 FT4I; r = 0.84; P less than 0.001). Ten to 14 days after acute T4 suppression in 5 euthyroid subjects, serum TSH/FT4I levels had plateaued after decreasing in parallel to the slope of the steady state relationship, suggesting that the degree of T4 suppression of TSH can be predicted from an individual's pituitary TSH/free T4 set-point and the magnitude of the serum T4 elevation achieved. Ambulatory and hospitalized patient sera, previously identified as having low (less than 0.1 mU/L) TSH levels by a less sensitive assay, were restudied by the TSH ICMA. Normal TSH values ranged from 0.39-4.6 mU/L, whereas the majority of hyperthyroid patients [52 of 54 (96% ambulatory) and 22 of 23 (96%, hospitalized)] had undetectable (less than 0.005 mU/L), basal TSH levels and absent TRH stimulated TSH responses. In contrast, most (32 of 37; 86%) of hospitalized nonhyperthyroid patients with low (less than 0.1 mU/L) TSH values due to nonthyroidal illness or glucocorticoid treatment had detectable (greater than 0.01 mU/L) basal and TRH stimulated TSH levels. The positive relationship between basal and TRH-stimulated TSH levels was shown to extend down to the detectability limit of the assay (0.005 mU/L), which further supported the authenticity of the subnormal TSH ICMA measurements. The new TSH ICMA is considered to represent the first of a third generation of clinical TSH assays, since it has a functional (interassay) sensitivity that is 2 orders of magnitude greater than that of typical first generation TSH RIAs and 1 order of magnitude greater than current second generation TSH immunometric methods. Such third generation TSH assays will facilitate both the optimization of T4 therapy as well as the diagnosis of hyperthyroidism in hospitalized patients with nonthyroidal illness.

0 comments Cited 53 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Screening for congenital hypothyroidism: results of screening one million North American infants.

Delbert A. Fisher, Jean Dussault, Thomas P. Foley … (1979)

Pilot programs for screening of newborn infants for congenital hypothyroidism began in North America in 1972. To date, the five oldest programs (Quebec, Pittsburgh, Toronto, Oregon Regional, and New England Regional) have screened 1,046,362 infants. A total of 277 infants with congenital hypothyroidism have been detected and seven have been missed, resulting in a total of 284 affected infants in the screened population and an overall incidence of one in 3,684 live births. Of the affected infants, 246 were determined to have primary hypothyroidism, an incidence of one in 4,254 births. Ten infants with secondary-tertiary hypothyroidism were detected in Quebec, Oregon, and Toronto, an incidence of one in 68,200 births. Of all the infants with primary hypothyroidism who were adequately studied, 63% were determined to have aplastic or hypoplastic glands, 14% normal or enlarged glands, and 23% ectopic thyroid tissue. The estimated minimum incidence of infants with TBG deficiency is one in 8,913 births. Only 8 of the 277 detected infants were suspected clinically to have congenital hypothyroidism prior to the time of confirmation of the diagnosis at 4 to 8 weeks of age. The cost of screening varied from $0.70 to $1.60 per infant, depending on which costs were included in the estimate. Preliminary evidence from Quebec suggests that infants treated in the program have normal developmental testing scores at 18 months of age.

0 comments Cited 31 times – based on 0 reviews      Review now

Bookmark

All references

Author and article information

Journal

Journal ID (publisher-id): HRE

Journal ID (nlm-ta): Horm Res Paediatr

Journal ID (doi): 10.1159/issn.1663-2818

Title: Hormone Research in Paediatrics

Publisher: S. Karger AG

ISSN (Print): 1663-2818

ISSN (Electronic): 1663-2826

Publication date Subscription-year: 2004

Publication date (Print): September 2004

Publication date (Electronic): 13 September 2004

Volume: 62

Issue: 2

Pages: 79-83

Affiliations

^aIsfahan Endocrine & Metabolism Research Center, ^bDepartment of Pediatrics, School of Medicine, ^cDepartment of Social Medicine, School of Medicine, ^dDepartment of Infectious Diseases, School of Medicine, and ^eDepartment of Physiology , School of Medicine, Isfahan University of Medical Sciences & Health Services, Isfahan, Iran

Article

Publisher ID: 79392 Other ID: Horm Res 2004;62:79–83

DOI: 10.1159/000079392

PubMed ID: 15237248

SO-VID: f95349da-9701-40aa-85af-4dadbdf2655a

License:

Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

History

Date received : 27 September 2003

Date accepted : 20 April 2004

Page count

Tables: 4, References: 45, Pages: 5

Comments

Comment on this article

scite_

Cited by 30

See all cited by

Most referenced authors 198

See all reference authors

- Version 1

Prevalence of Congenital Hypothyroidism in Isfahan, Iran: Results of a Survey on 20,000 Neonates

Read this article at

Abstract

Related collections

Karger: Endocrinology

Most cited references 21

Timing of vulnerability of the brain to iodine deficiency in endemic cretinism.

Applications of a new chemiluminometric thyrotropin assay to subnormal measurement.

Screening for congenital hypothyroidism: results of screening one million North American infants.

Author and article information

Journal

Affiliations

Article

History

Page count

Categories

Comments

Comment on this article

Similar content 290

Cited by 30

Most referenced authors 198