Thyroidology最新文献

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.

The prevalence of thyroid abnormalities was determined in 131 patients: group I = rheumatoid arthritis, 68 patients, group II = systemic immunological diseases (IIa Sjögren's syndrome, n = 6; IIb other rheumatic autoimmune disease, n = 17), group III = other rheumatic diseases n = 13 and control group (n = 27). Thyroid abnormalities (hypo, hyperthyroidism, nodular goiter) were frequent: 33.8% in group I, 100% in group IIa, 11.7% in group IIb. Hypothyroidism was present in 19.1% (group I), 50% (group IIa). 6% (group IIb). Autoimmune thyroiditis was found in 16.2% in group I, 100% in group IIa, 11.7% in group III. Thyroid diseases are frequent in patients with rheumatoid arthritis. Therefore thyroid tests might be performed in patients with rheumatoid arthritis.

The purpose of this review is to describe the two imaging methods which allow direct estimation of stable iodine (127I) within thyroid gland either in vivo by X-ray fluorescence or in vitro by secondary ion mass spectrometry (SISM) microscopy. X-ray fluorescence of thyroid is mainly used for the estimation of thyroid iodine content (TIC) in human pathophysiology. Although its measurement has little revelance for routine explorations of thyroid function, this is a valuable method for understanding complex pathophysiological conditions such as hyperthyroidism without radioactive uptake, the fate of irradiated glands or the thyroid adaptation to iodine overload. On the other hand, SIMS microscopy which combines the phenomena of secondary ion emission and mass spectrometry, makes possible the quantitative mapping of 127I on tissue section. This technique is able to characterize the functional activity of thyroid tissue without prior administration of radioiodine by measuring 127I concentration within the thyroid follicles. Furthermore, SIMS microscopy can be used to determine the extent to which exogeneous iodine affects the regulation of iodine within the thyroid follicles. Both methods were used to evaluate the quantitative changes in thyroid 127I induced by amiodarone overload. TIC measurements shows that hyperthyroidism occurred only in patients who increased their iodine stores, while the patients who developed hypothyroidism had low iodine stores. These data demonstrate that the mechanisms by which subjects who become hypothyroid under amiodarone iodine overload differ from those of subjects who remain euthyroid or become hyperthyroid: iodine organification is blocked in hypothyroid patients and increased in the euthyroid and hyperthyroid patients. The SIMS microscopy data obtained in mice demonstrated that the thyroid response to amiodarone is related to dietary iodine intake leading to an increase in iodine stores in iodine deficient mice and a decrease in iodine supplemented mice. These results could explain that hyperthyroidism with high thyroid iodine content occurred in areas with low thyroid iodine intake and hypothyroidism with low thyroid iodine content in areas with a supplemented iodine diet.

All cases undergoing neck operation for thyroid or parathyroid disease at Lund University Hospital, Lund, over a 7 year period were examined with indirect laryngoscopy pre- and postoperatively for the determination of the true incidence of operatively induced palsy of the recurrent laryngeal nerves. A total of 1.048 patients were operated; 810 females and 238 males. At 439 operations, bilateral neck exploration was performed; hence, 1.487 nerves were at risk for complications. It was found that immediate postoperative recurrent laryngeal nerve palsy was induced in 72 patients (= 4.8% of nerves at risk). In 44 of these patients, the palsy was temporary and disappeared within 6 months. Therefore, a total of 28 patients developed permanent nerve palsy postoperatively. In 5 of these operations, the nerve was intentionally divided, yielding a true incidence of permanent accidental postoperative nerve palsy of 1.6% of nerves at risk.

Serum TT4, FT4, TT3, FT3 and TSH, concentrations were measured before and 0.5, 1, 2, 3, 4, 5 hours after a single oral dose of L-T4 (150 micrograms) in 21 clinically euthyroid goitrous patients on a long-term therapy program. The mean basal TT4 concentration, 8.85 +/- 0.52 micrograms/dl (mean +/- se), increased significantly at the second hour (10.04 +/- 0.52 micrograms/dl, p < 0.001) and reached the highest value at the third hour (10.35 +/- 0.55 microgram/dl, p < 0.001). Subsequently the mean serum TT4 concentration remained elevated until the fifth hour (10.20 + 0.60 microgram/dl, p < 0.001). The mean basal value of FT4 concentration, 8.66 +/- 0.40 pg/ml, increased significantly at 30 minutes (9.19 +/- 0.40 pg/ml, p < 0.01) and reached the highest value at the third hour (11.81 +/- 0.56 pg/ml, p < 0.001). The mean basal serum FT3 concentration, 3.56 +/- 0.10 pg/ml, increased significantly 30 minutes (3.72 +/- 0.11 pg/ml p < 0.05) after L-T4 administration; the mean serum FT3 concentration was significantly higher than the basal level and 1 and 2 hours as well, and reached the highest value at the third hour (3.86 +/- 0.09 pg/ml). The mean serum TT3 concentration did not show any significant change at any time. The mean basal TSH value (2.73 +/- 0.42 microUI/ml) declined progressively. At 30 minutes it decreased significantly (2.29 +/- 0.38 microUI/ml, p < 0.01) and reached the lowest value at the fifth hour (1.39 +/- 0.26 microUI/ml, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

To evaluate the influence of age on clinical findings of thyroid disease, the records of 209 consecutive hospitalized patients with hyperthyroidism (n = 109) or hypothyroidism (n = 100) over a ten year period (1979 to 1988) were retrospectively reviewed. Patients included 51 males and 158 females, aged 21-99 years. Control euthyroid subjects (n = 70) were selected in the same age range and for similar non-thyroid illness as patients. Patients and controls were sorted by age decade of life. For each group a clinical index was calculated on the basis of 10 symptoms and 10 signs most frequently observed in thyroid disease. With increasing age, the occurrence rate of the clinical manifestations of thyroid disease decreased in patients while it increased in controls. This opposite evolution was less marked in hypothyroidism than in hyperthyroidism and was independent of biological parameters which remained stable whatever the age of patients and controls. Specific clinical features were identified for hyper- and hypothyroidism but none of them had sensitivity higher than 60% except goiter in hyperthyroid patients aged 61-80. In conclusion, a clinical diagnosis of thyroid disease is difficult in aged subjects because there are only a few specific features and their frequency is low. Therefore, in subjects over 60 years, we advocate performance of thyroid biochemical screening.

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.

A case is presented of hyalinizing trabecular adenoma in a 54-year-old Japanese female. The patient underwent a hemithyroidectomy for the diagnosis of thyroid carcinoma. An intraoperative frozen section diagnosis was medullary carcinoma. Hematoxylin and eosin stained permanent sections from the surgical specimen, a well encapsulated 3.0 x 2.0 x 1 cm nodule, also led us to suspect medullary carcinoma, but immunohistochemical staining for thyrocalcitonin, CEA, and thyroglobulin showed that it was a hyalinizing trabecular adenoma.

The molecular mechanisms underlying the development of endocrine active thyroid tumors are poorly understood. These tumors produce excess thyroid hormone, which then suppresses TSH (thyroid stimulating hormone) production. In the present report, we show that the expression of Gi alpha-1 is under control of TSH in the normal human thyroid. In contrast Gi alpha-1 escapes TSH control in autonomous adenoma and thus is constitutively expressed. Since receptor-mediated activation of Gi controlled pathways is known to elicit a proliferative response in several cell types, we propose that in thyroid adenomas the unregulated constitutive expression of Gi alpha-1 is causally related to the autonomous growth.

Some authors have suggested a role of autoimmunity in the pathogenesis of iodine deficiency disorders (IDD). For this purpose we have searched for thyroid adenylate cyclase stimulating antibody (TSAb) and thyroid growth stimulating antibody (TGSAb) in patients with endemic goiter (EG) and endemic cretinism (EC). Immunoglobulins G preparations (IgGs) were tested in FRTL-5 cells. TSAb were calculated as percent of cAMP increase over basal production and TGSAb were expressed as percent of increase of 3H-thymidine incorporation and DNA content in FRTL-5 cells. Our results show that IgGs from goitrous patients were devoid of TSAb and TGSAb activities, while in the same conditions IgGs from patients with Graves' disease had the ability to stimulate cAMP production and 3H-thymidine incorporation in FRTL-5 cells. These data argue against a direct role of TSAb and TGSAb in the pathogenesis of IDD.