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Biomedical subjects

L Hegedüs

Publications and source records attributed to L Hegedüs.

At least 19 recordsLinked to original sources
PubMed1992

Impaired 1,25-dihydroxyvitamin D production in pregnancy-induced hypertension.

The aim of the study was to evaluate the calcium metabolism in pregnancy-induced hypertension. Fifty-three women with pregnancy-induced hypertension were studied and the control groups comprised 20 women with uncomplicated pregnancies in the third trimester and 51 non-pregnant women, respectively. The mean serum concentrations of 1,25-dihydroxyvitamin D in women with pregnancy-induced hypertension was low (38.6 +/- 21.4 pg/ml) compared to women with uncomplicated pregnancies (91.0 +/- 18.2 pg/ml), but comparable to levels in non-pregnant women (32.2 +/- 11.9 pg/ml). Mean serum levels of PTH and ionized calcium were comparable in women with pregnancy-induced hypertension and women with uncomplicated pregnancies. In conclusion, the calcium metabolism in pregnancy-induced hypertension was changed compared to uncomplicated pregnancies with respect to the serum concentration of 1,25-dihydroxyvitamin D.

Adult↗
PubMed1992

Treatment of hypothyroidism reduces low-density lipoproteins but not lipoprotein(a).

Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL) particle in which apolipoprotein B-100 (apo B) is attached to a large plasminogen-like protein called apolipoprotein(a) [apo(a)]. Apo(a) has several genetically determined phenotypes differing in molecular weight, to which Lp(a) concentrations in plasma are inversely correlated. LDL and apo B levels are often elevated in untreated hypothyroidism and lowered by thyroxine (T4) treatment, probably due to an increase in LDL receptors. We measured plasma concentrations of LDL, apo B, and Lp(a) in 13 patients with symptomatic primary hypothyroidism before and during T4 therapy. The mean concentration of LDL decreased significantly (P = .006) from 6.05 mmol/L to 4.07 mmol/L, and the mean concentration of apo B decreased significantly (P = .005) from 1.42 g/L to 1.12 g/L. Median Lp(a) concentrations remained unchanged (P = .77); they were 17.05 mg/dL before and 16.59 mg/dL during T4 treatment. In both the untreated condition and during substitution therapy, Lp(a) levels were higher in patients than in healthy controls, probably due to a relatively high frequency of the small Lp(a) phenotypes in our patients. Since Lp(a) contains apo B, which is a ligand for the LDL receptor, it is surprising that Lp(a) is not reduced along with LDL and apo B. These findings suggest that the catabolism of LDL and Lp(a) differ in some respect, and that thyroid hormones have little, if any, effect on Lp(a).

Female↗
PubMed1992

Subtle changes in serum thyrotrophin (TSH) and sex-hormone-binding globulin (SHBG) levels during long-term follow-up after radioactive iodine in multinodular non-toxic goitre.

OBJECTIVE: We investigated possible changes in the pituitary-thyroid axis after radioactive iodine (RAI) treatment of multinodular non-toxic goitre. DESIGN: Consecutive patients with multinodular non-toxic goitre, who remained euthyroid after radioactive iodine (RAI) treatment. PATIENTS: Twenty-three women with multinodular non-toxic goitre were followed after treatment with RAI. MEASUREMENTS: Free T4 index (FT4I), FT3I, free T4, SHBG (immunoradiometric assay), and a third-generation TSH assay (chemiluminetric assay) TSH were measured. RESULTS: Three weeks after RAI treatment TSH had decreased and SHBG increased (P < 0.05). Only 2/18 patients actually had suppressed TSH values, while 12/18 had values in between euthyroid and toxic levels. Trend analysis from 1.5 to 24 months after RAI treatment demonstrated a progressive increase in TSH (P < 0.01) and gradual decrease in SHBG (P < 0.02). No changes in FT4I, FT3I, or free T4 were found. CONCLUSION: A third-generation TSH assay gave detailed information about changes in thyroid status when TSH was below normal values. FT4I, FT3I, and free T4 seem to be less sensitive parameters than TSH and SHBG for recording subtle changes in thyroid status after RAI treatment of nodular non-toxic goitre. We demonstrated that changes in the pituitary-thyroid axis continue for a long time after RAI treatment of multinodular non-toxic goitre. These patients should be followed up in order to detect possible late hypothyroidism.

Adult↗
PubMed1992

Effect of occupational exposure to cobalt blue dyes on the thyroid volume and function of female plate painters.

It has previously been shown that long-term oral exposure to cobalt can cause goiter and myxedema. The effect of industrial cobalt exposure on thyroid volume and function was determined for 61 female plate painters exposed to cobalt blue dyes in two Danish porcelain factories and 48 unexposed referents. Thyroid volume was determined by ultrasonography. The cobalt blue dyes were used in one of two forms, cobalt aluminate (insoluble) and cobalt-zinc silicate (semisoluble). Only the subjects exposed to semisoluble cobalt had a significantly increased urinary cobalt content (1.17 micrograms.mmol-1 versus 0.13 micrograms.mmol-1, P less than 0.0001). These subjects also had increased levels of serum thyroxine (T4) and free thyroxine (FT4I) (P = 0.0001 and 0.0029, respectively), unaltered serum thyroid stimulating hormone (TSH), and marginally reduced 3,5,3'-triiodothyronine (T3), whereas thyroid volume tended to be lower (P = 0.14). The group exposed to insoluble cobalt did not differ significantly in any thyroid-related parameters. No correlation between urinary cobalt and FT4I or thyroid volume was found. The study demonstrates an effect of cobalt on thyroid hormone metabolism.

Air Pollutants, Occupational↗
PubMed1992

Thyroid stimulating immunoglobulins are not influenced by smoking in healthy subjects.

In view of the increasing suggestion of an effect of cigarette smoking on thyroid disease and in particular Graves' ophtalmophathy we investigated thyroid stimulating immunoglobulins in relation to smoking habits in healthy subjects. No difference between smokers and non-smokers could be demonstrated, therefore, our study does not support the previously suggested altered immunologic surveillance of the thyroid in cigarette smokers.

Adenylyl Cyclases↗
PubMed1992

Is standard 555 MBq 131I-therapy of hyperthyroidism ablative?

The effect of a standard 555 MBq 131I dose in ablating the thyroid gland was investigated in 116 consecutive hyperthyroid patients. Fifty-one had Graves' disease, 50 a multinodular toxic goitre and 15 had a solitary toxic nodule. 555 MBq 131I was given regardless of size or type of the gland and severity of the disease. Within one year after this dose hypothyroidism was induced in 41% of patients with Graves' disease, but in only 13% with a solitary toxic adenoma, and 6% with a multinodular gland. Forty-eight percent of the patients with a multinodular gland, 33% with Graves' disease and 13% with a solitary toxic nodule were still hyperthyroid. Since this so called ablative treatment only accomplishes hypothyroidism in 26/116 (23%) of our patients and results seem unpredictable 131I treatment adjusted according to gland size and type aiming at achieving euthyroidism could be contemplated.

Adenoma↗
PubMed1992

Inadequacy of the WHO classification of the thyroid gland.

In order to evaluate the reproducibility of the WHO classification of goitre, the observer variation was estimated as kappa coefficients. Three observers independently inspected and palpated the thyroid gland of 53 patients twice and assessed the thyroid according to the five grades of the WHO classification. The thyroid volume was also measured by ultrasonography. We found kappa values from 0.15 to 0.70 in the interobserver study, and from 0.02 to 0.89 in the intraobserver study. Considerable overlap between the five grades was demonstrated when the assessments were related to volume estimated by ultrasonography. Description of the thyroid gland according to the WHO classification is inaccurate and not reproducible and is therefore of limited value.

Adult↗
PubMed1991

The thyroid function and size in healthy man during 3 weeks treatment with beta-adrenoceptor-antagonists.

The influence of beta-adrenoceptor antagonists on serum TSH level (supersensitive method) and thyroid volume has not previously been studied. Thirty-two young non-smoking males were treated for 3 weeks with either atenolol 50 mg (b.i.d.), metoprolol 100 mg (b.i.d.) or propranolol 80 mg (b.i.d.) in a placebo controlled study. After 1 week, median serum TSH level increased in the atenolol (from 1.76 (range: 0.96-4.04) to 2.25 (range: 1.11-4.22) mU/l, P less than 0.05) and propranolol (from 1.91 (range: 0.90-3.83) to 2.44 (range: 0.75-6.30) mU/l, P less than 0.05) treated groups. After 3 weeks, median serum TSH reached pretreatment level in the atenolol treated, whereas median serum TSH decreased compared to pretreatment values in the propranolol treated (1.68 (range: 0.68-3.62) mU/l, P less than 0.05). Except for a slight increase in the atenolol treated group, no changes in median thyroid volume was seen after 3 weeks. The changes in serum TSH or thyroid volume were not related to changes in the concentrations of thyroid hormones, or of a magnitude likely to interfere with the clinical evaluation of thyroid function.

Adrenergic beta-Antagonists↗
PubMed1991

Glucose tolerance and incidence of pancreatic islet cell antibodies in pregnancy in women with thyroid autoantibodies.

The prevalence of pancreatic islet cell antibodies (ICA) and complement fixing ICA (CF-ICA) and the effect of pregnancy of glucose tolerance was studied in 3 groups of women. One group had thyroid autoantibodies in serum detected in early pregnancy and subsequent development of postpartum thyroiditis (PPT), another group had thyroid autoantibodies without signs of PPT and the third group did not have thyroid autoantibodies or PPT. In the women with thyroid autoantibodies and PPT, ICA were found in one of 12 women (8%, 95% confidence limits 0-38%). In the group with thyroid autoantibodies without PPT, ICA were found in three of 27 women (11%, 2-29%), whereas two of 20 women without thyroid autoantibodies had ICA (10%, 1-32%), N.S. Where present, serum ICA levels were very low and similar in early pregnancy and 6 months postpartum. CF-ICA were only found in two women with thyroid autoantibodies without signs of PPT. In all groups glucose tolerance was impaired in pregnancy when compared to postpartum despite an increased insulin response to glucose ingestion. In pregnancy, however, glucose tolerance was more impaired in the women with thyroid autoantibodies and subsequent PPT, than in the women without thyroid autoantibodies. Postpartum glucose tolerance was similar in all groups. It is concluded, that the presence of thyroid autoantibodies in early pregnancy or development of PPT is not accompanied by an increased prevalence of islet cell antibodies, but women with thyroid autoantibodies and subsequent PPT have a significantly more reduced glucose tolerance in late pregnancy than women without thyroid autoantibodies.

Adult↗
PubMed1991

Influence of thyroxine treatment on thyroid size and anti-thyroid peroxidase antibodies in Hashimoto's thyroiditis.

OBJECTIVE: It has been postulated that a decrease in thyroid size can be achieved by thyroxine treatment in patients with goitrous Hashimoto's thyroiditis but no objective data are available. We have therefore investigated the influence of thyroxine treatment on ultrasonically determined thyroid size. We also measured serum antithyroid peroxidase antibodies. DESIGN: Consecutive patients with goitrous Hashimoto's thyroiditis was studied. PATIENTS: Thirteen women participated; all had goitrous thyroiditis. TREATMENT: To render them euthyroid thyroxine was given for 24 months. MEASUREMENTS: Thyroid size was measured ultrasonically and antithyroid peroxidase antibodies were measured using a commercial radioimmunological method. RESULT: Concomitant with the gradual increase in serum free thyroxine and free triiodothyronine index values and a fall in serum thyrotrophin level, a gradual decrease in thyroid volume from 50.4 +/- 6.8 ml (mean +/- SEM) to 34.1 +/- 5.7 ml (32%), P less than 0.001 was demonstrated. Antithyroid peroxidase antibodies were present in high concentrations in all subjects but the mean serum level was not significantly changed at 24 months after initiation of treatment. CONCLUSION: A clinically significant reduction in thyroid volume related to normalization of thyroid function but unrelated to changes in antithyroid peroxidase antibody can be achieved during L-thyroxine treatment of hypothyroid goitrous Hashimoto's thyroiditis.

Adult↗
PubMed1991

Observer variation in the clinical assessment of the thyroid gland.

In order to evaluate the reliability of clinical assessment of the thyroid gland, two specialists in endocrinology and two younger doctors independently examined 53 patients twice, and assessed whether they had a diffuse goitre, a multinodular goitre, a solitary nodule or a normal gland. In 30% of the patients all four observers were in agreement, whereas in 47% and 23% of the patients, two and three different diagnoses were given, respectively. Inter-observer variation was determined and kappa values between -0.04 and 0.54 were found. Intra-observer variation was smaller, revealing kappa values between 0.44 and 1.00. The present study suggests that clinical assessment of the thyroid gland may lead to misclassification of the type of thyroid disease, and thereby to a less than optimal choice of therapy.

Adult↗
PubMed1991

Effect of maternal thyroid autoantibodies and post-partum thyroiditis on the fetus and neonate.

Thirty-five pregnant women with thyroid antibodies were followed during pregnancy and 12 month post partum. Twenty antibody-negative women served as controls and none of these developed postpartum thyroiditis in contrast to 12 of 35 antibody-positive women. Umbilical cord blood was collected at birth for measurements of thyroid antibodies, and blood samples for measurements of thyroid hormones were obtained at 5 and 30 days of age in the infants together with a clinical examination. There were no differences between the infants of antibody-positive and -negative mothers or the infants of those who developed postpartum thyroiditis with regard to gestational age at birth, birth weight, birth length or Apgar score, and no difference in thyroid function of the mothers and infants. However, serum TSH level was significantly higher in mothers who subsequently developed postpartum thyroiditis. Furthermore, a significantly lower growth during the first 30 days of life was observed in their infants. Our observations suggest a relationship between the maternal thyroid status in pregnancy and early growth in infancy.

Autoantibodies↗
PubMed1991

Anti-thyroid peroxidase antibodies in thyroid disorders and non-thyroid autoimmune diseases.

A new commercial method for measurement of anti-thyroid peroxidase (anti-TPO DYNOtest, Henning, Berlin) was evaluated in normal subjects and in patients with autoimmune thyroid and non-thyroid diseases, and compared to an immune fluorescence method for measurement of anti-microsomal antibodies (MicAb), and a radioimmunological method for quantifying thyroglobulin antibodies (TgAb). The majority of normal subjects had anti-TPO levels below 52 U/ml and patients with Hashimoto's thyroiditis had levels above 200 U/ml, with a good correlation to MicAb. In other autoimmune thyroid diseases the correlation was less pronounced. In non-thyroid autoimmune diseases MicAb showed falsely positive reactions in the presence of other autoantibodies, e.g. mitochondrial antibodies. The present study indicates that the anti-TPO method should probably replace measurements of MicAb for routine clinical use, thus providing a sensitive, precise, antigen specific method with the ability to reveal quantitative fluctuations. The study also indicates that TgAb could be abolished in routine diagnosis of autoimmune thyroid diseases and be reserved for special clinical situations, research purposes as well as measurement in sera before evaluation of serum thyroglobulin levels.

Adolescent↗
PubMed1991

Accuracy of the clinical assessment of thyroid size.

A number of clinical decisions regarding treatment of thyroid diseases are influenced by the evaluation of thyroid size. In order to evaluate the accuracy of clinically estimated thyroid size, two experienced specialists in endocrinology and two junior doctors independently examined 53 patients. The ultrasonically-determined size was used as standard. An average error of 39% (range 0-566%) was demonstrated, the experienced doctors being more accurate than the younger ones. No relation was found between type of gland and accuracy of clinical estimation. In conclusion, palpation of the thyroid should not be used when an accurate size evaluation is considered of importance, e.g. in the estimation of radioiodine dose.

Adult↗
PubMed1991

Ultrasonically guided fine-needle biopsies from adrenal tumors.

Ultrasonically guided fine-needle biopsies were performed from 28 adrenal lesions in 28 patients. In 15 patients adrenal enlargement was an incidental finding. In 17 of 18 (94%) patients with metastatic spread combined cytological and histological examination disclosed secondary malignancy, and in 4 of 5 patients with primary neoplastic disease the combined microscopic examination concluded primary neoplasia. However, it was not possible to classify these lesions as being of a malignant or a benign nature. A false positive diagnosis of a hepatocellular carcinoma of the clear cell type was made in one case. In all 5 patients with non-neoplastic adrenal lesions cytological and histological examinations concluded non-neoplastic disease. Electron microscopy was of special benefit in two cases of a non-Hodgkin's lymphoma and a pheochromocytoma. Using ultrasonically guided biopsies it is possible to differentiate between adrenal lesions due to metastatic spread and adrenal lesions due to primary neoplasia or non-neoplastic disease. Compared to other imaging techniques ultrasonically guided punctures of adrenal masses is a simple procedure giving important diagnostic information.

Adrenal Gland Neoplasms↗
PubMed1991

Kidney volume in type 1 (insulin-dependent) diabetic patients with normal or increased urinary albumin excretion: effect of long-term improved metabolic control.

Forty-seven patients with type 1 (insulin-dependent) diabetes mellitus and 14 normal subjects had renal volume determined by an ultrasonic technique. Renal volume of 299 +/- 49 ml/1.73 m2 (mean +/- SD) in type 1 diabetic patients with normal urinary albumin excretion exceeded that in the normal subjects (245 +/- 53 ml/1.73 m2, p less than 0.05). Compared with diabetic patients with normal urinary albumin excretion, renal volume was significantly higher in patients with microalbuminuria (372 +/- 24 ml/1.73 m2, p less than 0.05) and patients with clinical nephropathy (352 +/- 48 ml/1.73 m2, p less than 0.05). In a multiple linear regression with HbA1c, urinary albumin excretion, age, diabetes duration and mean blood pressure as independent variables, variations in HbA1c could account for 33% of the variations in kidney volume (n = 47, r = 0.57, p less than 0.01). The other variables played no role. When only patients without clinical nephropathy were included, HbA1c and kidney volume remained significantly correlated (n = 34, r = 0.60, p less than 0.01). In those patients a strong correlation between kidney volume and function, i.e. the glomerular filtration rate was found (n = 34, r = 0.70, p less than 0.01); metabolic control and function were also correlated (n = 34, r = 0.62, p less than 0.01). The urinary albumin excretion accounted for only 6% of the variation of the kidney volume (NS). In nine patients with microalbuminuria the kidney volume could be reduced during 2 years of improved metabolic control by means of insulin infusion pumps.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗