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Serum thyroglobulin (Tg) level was determined in 34 biologically euthyroid patients having benign hypofunctioning nodule, before and after surgery. Based on the results of thyroid scanning with radioiodine, 2 groups of patients were considered. Group 1 ( n=18) had solitary hypofunctioning nodule with an otherwise normal thyroid gland and group 2 ( n=16) had hypofunctioning nodule inside an enlarged and/or heterogenous thyroid. Results were compared to a group of 30 control subjects. Mean Tg level was significantly elevated in both groups 1 and 2 before surgery. No significant difference was found between group 1 and group 2. After surgical removal of the hypofunctioning nodule (follicular adenoma), mean Tg level was normalized in group 1 and decreased but still remained elevated in group 2. It is concluded that the observed elevated serum Tg level is due to the presence of hypofunctioning nodule and/or heterogenous thyroid tissue. Thus, Tg determination may be useful in the follow-up of operated hypofunctioning nodules in order to detect abnormality in the remaining thyroid tissue. [ABSTRACT FROM AUTHOR]

The postnatal development of rat microglia is marked by an important increase in the number of microglial cells and the growth of their ramified processes. We studied the role of thyroid hormone in microglial development. The distribution and morphology of microglial cells stained with isolectin B4 or monoclonal antibody ED1 were analyzed in cortical and subcortical forebrain regions of developing rats rendered hypothyroid by prenatal and postnatal treatment with methyl-thiouracil. Microglial processes were markedly less abundant in hypothyroid pups than in age-matched normal animals, from postnatal day 4 up to the end of the third postnatal week of life. A delay in process extension and a decrease in the density of microglial cell bodies, as shown by cell counts in the developing cingulate cortex of normal and hypothyroid animals, were responsible for these differences. Conversely, neonatal rat hyperthyroidism, induced by daily injections of 3,5,3'-triiodothyronine (T3), accelerated the extension of microglial processes and increased the density of cortical microglial cell bodies above physiological levels during the first postnatal week of life. Reverse transcription-PCR and immunological analyses indicated that cultured cortical ameboid microglial cells expressed the alpha1 and beta1 isoforms of nuclear thyroid hormone receptors. Consistent with the trophic and morphogenetic effects of thyroid hormone observed in situ, T3 favored the survival of cultured purified microglial cells and the growth of their processes. These results demonstrate that thyroid hormone promotes the growth and morphological differentiation of microglia during development.

We analyzed the kinetics of CD4 cells, human immunodeficiency virus (HIV) viral load, and autoantibodies in acquired immune deficiency syndrome patients with Graves' disease (GD) after immune restoration on highly active antiretroviral therapy (HAART; retrospective study). Five patients (median age, 41 yr) were diagnosed with GD after 20 (range, 14-22) months on HAART on the basis of clinical and biological hyperthyroidism, diffuse hyperfixation of thyroid scan, and the presence of anti-TSH receptor (anti-TSHR) antibodies (Ab). GD was diagnosed several months after the plasma HIV ribonucleic acid load became undetectable, when the CD4+ cell count had risen from 14 (range, 0-62) to 340 (range, 163-460) x 10(6) cells/L. Antithyroid peroxidase (anti-TPO) and anti-TSHRAb appeared 14 (range, 9-18) and 14 (range, 11-20) months after starting HAART and 12 (range, 6-15) and 11 (range, 9-17) months after the increase in CD4+ cells. In 3 patients, TPOAb preceded TSHRAb by 3-10 months. No other autoantibodies were detected. Thyroid antibodies were absent in a group of 55 HIV-1-positive patients with comparable response to HAART and no symptoms of hyperthyroidism (cross-sectional study). Thyroid-specific autoimmunity can occur upon immune restoration with HAART. Our observations suggest a relationship between thymus-dependent immune reconstitution after immunosuppression and autoimmunity and may provide insight into the pathophysiology of GD.

We performed a prospective random study to assess possible thyroid stunning by a 185-MBq iodine-131 dose used to diagnose thyroid remnants. Patients with differentiated thyroid carcinoma were included after total or near-total thyroidectomy. They were randomly assigned to two groups. In group 0 (G0, 32 patients), iodine-123 administration only was used to diagnose thyroid remnants and/or metastasis, so that no thyroid stunning by 131I would occur. In group 1 (G1, 19 patients), diagnostic imaging was performed with 123I and 185 MBq 131I. 123I imaging was less sensitive than 131I imaging in identifying thyroid remnants in both groups (94%). Thyroid uptake of 123I was measured in both groups (at 2 h) and was not significantly different between the groups. Patients with thyroid remnants who remained in the study (28/32 in G0, 17/19 in G1) were treated with 370 MBq 131I, 5 weeks after treatment (mean time, range 12-84 days). In 12/17 G1 patients thyroid uptake measurement was repeated immediately before treatment. Uptake was equal to 1.97% +/- 0.71% and significantly lower (P < 0.05) than the previous measurement (3.76% +/- 1.50%). Patients were imaged 7 days after administration of the therapeutic dose and the images were compared with the diagnostic images. In 28/28 G0 patients thyroid remnants were unchanged and clearly seen. In 5/17 G1 patients, however the remnants were hardly identified, although they had been clearly seen at the time of diagnosis. We conclude the following: (1) a diagnostic dose of 185 MBq 131I decreases thyroid uptake for several weeks after administration and can impair immediate subsequent 131I therapy; (2) 123I is slightly less sensitive than 131I in identifying thyroid remnants; and (3) the need to scan for thyroid remnants remains to be confirmed, since only 2/51 patients enrolled in this study were not treated with 131I.

Objective: To determine the prognostic value of suppressed thyrotropin (TSH) level and positive TSH-receptor antibodies (TSH-R Ab) in patients with Graves' disease who have long-lasting clinical remission., Methods: We retrospectively studied patients with Graves' disease who underwent follow-up for a mean of 55 months after the withdrawal of antithyroid drug treatment. Study patients were 84 consecutive subjects in clinical remission, with normal serum free thyroxine (FT(4)) and free triiodothyronine (FT(3)) levels, regardless of serum TSH levels, a mean of 35 months (range, 6 to 135) after discontinuation of carbimazole therapy. Eighty-seven euthyroid subjects were used as control study participants. All subjects had serum determinations of FT(4) and FT(3) (radioimmunoassay), TSH (highly sensitive immunoradiometric method), TSH-R Ab (radioreceptor assay), and microsomal antibodies (M Ab, passive hemagglutination method)., Results: In the study patients, serum TSH was suppressed (/=15%) in 11 cases (13%), and M Ab were positive (>/=1:100) in 54 cases (64%). Simultaneous suppressed TSH and positive TSH-R Ab levels were present in six patients. During the follow-up, 11 patients had a relapse, demonstrated by above-normal values for serum FT(4) and FT(3) in association with clinical symptoms of hyperthyroidism. Five of them had a previously suppressed TSH level, three had a positive TSH-R Ab level, and six had a positive M Ab titer. Relapse was significantly more likely in patients with a previously suppressed TSH level (P<0.02) but not in patients with a previously positive TSH-R Ab level or positive M Ab titer., Conclusion: Patients with Graves' disease and long-lasting clinical remission after discontinuation of carbimazole therapy may have a suppressed TSH level, a positive TSH-R Ab level, or a positive M Ab titer (or some combination of these findings). Although positive TSH-R Ab and M Ab have no significant prognostic value, a suppressed TSH level is indicative of subclinical hyperthyroidism and higher risk of relapse.

Unlabelled: Patients with an autonomously functioning thyroid nodule (ATN) may be present with various clinical, biochemical and scintigraphic features. To optimize 131I dose planning and treatment timing in these patients, relationships between dosimetric data and clinical follow-up events must be established., Methods: We retrospectively reviewed the records of 88 patients who received 131I (intended dose of 80 Gy) for an ATN, of whom 39 had evidence of extranodular activity (ENA) and 76 presented with overt thyrotoxicosis. In all of the patients, dosage calculation was monitored to estimate precisely both beta and gamma absorbed doses received by the ATN and the nodule-free lobe. The mean duration of follow-up was 75 mo (max 180) and always included biochemical thyroid tests. Finally, we compared the dosimetric profiles of four dosage schemes which had been normalized by simulation to ensure that the same absorbed dose threshold value was always delivered to the ATN., Results: About 75% of the patients were cured at 6 mo for a mean 305 MBq administered. The absorbed doses delivered to the nodule-free lobe ranged from 12% (no ENA) to 86% (ENA) of the values delivered to the ATN, mainly in the form of beta irradiation. Life-table estimates for hypothyroidism and death were 9.6% and 22% at 75 mo, respectively. Hypothyroidism mainly developed in patients with nonsuppressed TSH levels but regardless of ENA, which often accounted for multifocal disease., Conclusion: We suggest that fixed doses bordering on 370 MBq are advizable in younger individuals and in patients with mild thyrotoxocosis, while 555 MBq-740 MBq can be administered in other patients and that ENA indicates multifocal autonomy in patients with toxic ATN and is a further indication for radioiodine treatment which should be begun as soon as possible to avoid the development of cardiac complications.

We retrospectively reviewed the records of 224 patients with diffuse goiters treated with radioiodine, half of which received carbimazole. In all the cases, we carefully monitored the calculation of dosage. A lower percentage of early hypothyroidism but a higher failure rate was observed in the carbimazole subgroup. Nevertheless, after one year, a constant (4.5%) incremental rate of hypothyroidism was found regardless of carbimazole administration. Since we were able to precisely estimate the absorbed doses in our series, we evaluated by simulation the dosimetric profiles of nine methods of dose selection (MDS). These MDS were calibrated in such a way that the same threshold value of absorbed dose would always be reached at the thyroid level. We showed that the more elaborate the MDS, the more accurate the irradiation at the thyroid level and the lower the radiation dose administered. In patients not receiving carbimazole, a rapid MDS using modified early uptake measurements to predict the 24-hr actual value was found to be advisable. With patients receiving carbimazole and if a goal is to delay the occurrence of hypothyroidism, we advise MDS based on either a 48-hr uptake or on the calculation of the individual half-life.

In an earlier study, we evaluated the frequency of clinical manifestations of ovarian insufficiency after radioiodine therapy for thyroid cancer. We were thus led to consider the dose received by the ovary (DRO) during these treatments. In the literature, this dose is expressed as a function of the activity administered. However, in our study, the disorders were not correlated with the activity administered. Faced with this discrepancy, we have attempted to establish a dosimetric model using the parameters available for each patient. The results obtained show that besides the activity administered, which plays a role, morphological and kinetic factors specific to each individual have an importance that cannot be ignored when addressing this problem.

Authors have selected 1928 measurements of thyroglobulin and studied their value in the thyroid pathology. They show that elevated values of thyroglobulin, the only one response in this pathology, can, even if isolated, be the mode of revelation of thyroid illness. They insist, in order to explain this fact, on the presence of a "sixth factor" which depends upon the quality of the thyroid tissue.

The objective of this retrospective survey is a mini-computer system conceived ten years ago to treat all numerical information coming from a hospital unit of clinical biology. The options that we chose for its function remain valid on at least two patients: the necessity, for the hardware, to dissociate the treatment of information from the listing of voluminous files (the former should be done in the real time, using a mini-computer system situated inside the department, and the latter should be done in differed time, using a more sophisticated machine situated in a common computer center); the necessity, for the software, to use a common global system, but it cn be cut down to suit the particular need of individual user with whom there should be a permanent collaboration. The results obtained during this time are discussed. They seem sufficiently positive to invite a appraisal re-examination of the use of such systems (in spite of some disenchantment at present), in the light of new possibilities from present progress in shared time computer system.

Thyroid function was studied in 3 groups of adults (group I = 13 burned patients treated with non iodinated antiseptic, group II = 15 burned patients treated with polyvidone iodine, group III = 50 control subjects) in order to examine: the thyroid hormone status in burned patients, the possible incidence of plasma iodine overload on these endocrine parameters. Burned skin area and thyroid function were measured before treatment, then weekly for 3 weeks. Before treatment a decrease in plasma T4 and T3 with an increase in reverse T3 (rT3) and a decrease in plasma thyroxin binding globulin (TBG) were observed in burned patients. Free T4 index (T4/TBG) was normal, but T3 resin uptake (T3RU) was elevated. During treatment, plasma iodine increase sharply from 6.4 +/- 0.4 to 20.7 +/- 4.7 micrograms/100 ml (p less than 0.02) in group II. Endocrine parameters (not different between group I and II) progressively returned to normal, except for T3RU which remained elevated until the third week. rT3, T4 and T3RU correlated (p less than 0.001) with burned skin area. To conclude, the reversible particularities of thyroid function in burned patients are positively correlated with burned area. The thyroid function does not seen to be modified by plasma iodine overload.

Investigations in 6 cases of congenital or acquired athyreosis show that serum thyroglobulin determined in these cases by radioimmunology is not due to a determination artifact or to another protein, but that, with regard to immunoreactivity, molar mass and isoelectric point, it displays all the features of the standard thyroglobulin of thyroid origin and of the serum thyroglobulin of normal subjects. The authors conclude that small quantities of thyroglobulin are present in the serum of such patients, even where all the other criteria of athyrosis appear to be present.