+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found

      Free Thyroxine Measurement by One-Step Method in the Plasma of Treated and Untreated Hypothyroid Infants

      Read this article at

          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.


          The one-step radioimmunoassay of free thyroxine (f-T<sub>4</sub>) using a gamma-coated kit was used in this study. In controls the mean plasma levels (pmol/l) were 20.8 (range 13.5–37) during the first days of life, 17.4 (11.5–27) from 1 week to 1 year, and 17.0 (10–24.5) after 1 year. In preterm newborns it was correlated with the length of gestation. Among 23 untreated hypothyroid infants aged 15–22 days, f-T<sub>4</sub> was undetectable in those with athyreosis, while in cases with dysgenetic thyroid it was variable, correlated to the width of the gland (r = 0.77, p < 0.01). In 44 hypothyroid patients treated with l-T<sub>4</sub>, a highly significant positive correlation was found after the 1 st month of treatment between plasma f-T<sub>4</sub> and the daily l-T<sub>4 </sub>dose (r = 0.46, p < 0.01), and a negative one between f-T<sub>4</sub> and plasma TSH (r = -0.59, p < 0.001). It is concluded that measurement of f-T<sub>4</sub> offers a valuable means for control of diagnosis and treatment in congenital hypothyroidism, especially useful for avoiding both under-and overtreatment. Its correlations suggest that it is the most reliable hormonal measurement in the follow-up of thyroid children.

          Related collections

          Author and article information

          Horm Res Paediatr
          Hormone Research in Paediatrics
          S. Karger AG
          26 November 2008
          : 22
          : 1-2
          : 110-114
          aUnité d’Endocrinologie Pédiatrique, Hôpital Saint-Vincent-de-Paul, et bLaboratoire des Isotopes, Hôpital Cochin, Paris, France
          180082 Horm Res 1985;22:110–114
          © 1985 S. Karger AG, Basel

          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.

          Page count
          Pages: 5
          Pediatric Endocrinology


          Comment on this article