Soluble forms of adhesion molecules sELAM-1 and sICAM-1 in Graves disease and toxic nodular goiter

Intercellular adhesion molecule-1 (ICAM-1) and endothelial leukocyte adhesion molecule-1 (ELAM-1) are playing a significant role in an inflammatory process. In patients with autoimmune disorders of thyroid gland an increased expression of ICAM-1 and ELAM-1 was found in thyroid and also in orbital tissue in presence of active ophthalmopathy. Reports concerning concentrations of adhesion molecules soluble forms (sELAM-1 and sICAM-1) in sera of patients suffered from different thyroid gland diseases are controversial. The aim of the project was an estimation of levels of adhesion molecules soluble forms in sera of patients with Graves' disease (GD) and toxic nodular goiter (TNG). In the presented research work sICAM-1 and sELAM-1 were determined in 149 subjects (aged 17-69 years) divided to following groups: group 1--16 hyperthyroid GD patients with active ophthalmopathy (GO) (10 females and 6 males); group 2--25 euthyroid GD patients with GO (17 females and 8 males); group 3--41 hyperthyroid GD patients without GO (22 females and 16 males); group 4--36 patients with TNG (20 females and 16 males) and control group (group 5)--31 healthy subjects (16 females and 16 males). sICAM-1 and sELAM-1 serum concentrations were determined using highly sensitive enzyme linked immunosorbent assay (ELISA). In comparison with control group (group 5) in groups 1--3 significant increase of sICAM-1 and sELAM-1 concentrations was found (p < 0.001). The highest values for both adhesion molecules were demonstrated in the group of hyperthyroid GD patients with GO (group 1) as well as in group of euthyroid GD patients with GO (group 2). In group 1 the values were higher than those in group 2. Lower concentrations were present in group of GD patients with hyperthryroidism without symptoms of GO (group 3). The lowest adhesion molecules concentrations in four examined groups were present in sera of patients with TNG (group 4). The level of sICAM-1 in this group was higher than that in control group, but the difference was not statistically significant (p < 0.01), on the contrary sELAM-1 concentration was markedly elevated in comparison with group 5 (p < 0.002). From the obtained results it may be concluded that elevated sICAM-1 and sELAM-1 concentrations in sera of GD patients are dependent on autoimmunological factors, presence of inflammatory changes in the orbital tissue as well as on hyperthyroidism. Nonautoimmune hyperthyroidism has also influence on increase of sICAM-1 and sELAM-1 levels.     

血清可溶性细胞间黏附分子1、透明质酸水平与Graves眼病疾病活动性之间的关系

探讨可溶性细胞间黏附分子1( sICAM-1)和透明质酸(HA)能否反映Graves眼病(GO)的疾病活动性.用ELISA方法检测48例GO患者(眼病组)的sICAM-1、HA水平,同时检测30例单纯Graves甲状腺功能亢进患者作为对照组.与对照组相比,眼病组的血清sICAM-1、HA水平明显增高(P＜0.05);且眼病组活动期的血清sICAM-1、HA水平明显高于稳定期(P＜0.05).Pearson相关性分析显示眼病组的血清sICAM-1、HA水平均与眼病活动分数(CAS)呈显著正相关(r=0.53,P＜0.01;r=0.46,P＜0.01),且sICAM-1与HA亦呈正相关(r=0.31,P＜0.05).GO患者外周血sICAM-1、HA水平可作为评价GO活动性的指标.     

Increased retinal blood flow in patients with Graves' disease: influence of thyroid function and ophthalmopathy

OBJECTIVE: Graves' ophthalmopathy (GO), resulting from the inflammation of retro-orbital tissue, is one of the major complications of Graves' disease (GD). We investigated the clinical usefulness of the measurement of retinal blood flow (RBF) in the evaluation of GO and its activity. MEASUREMENT: RBF was quantitated by pulsed Doppler mode at just below the branch of central retinal artery, from which the resistance index (RI) was calculated. PATIENTS: Forty-seven euthyroid GD patients and 70 gender- and age-matched normal controls were measured for RI to investigate the effect of GO on RBF. To investigate the effect of hyperthyroidism, 20 GD patients were measured for RI changes during antithyroid drug (ATD) therapy. Furthermore, 17 GD patients with clinically overt GO were measured for RI changes during treatment with glucocorticoid plus retro-orbital radiation. RESULTS: RI and exophthalmos showed a significant positive correlation in 47 treated euthyroid GD patients without clinically overt GO (r=0.307, P<0.05), but not in 70 age- and sex-matched normal subjects (r=0.185, P=0.161). Furthermore, RI, but not exophthalmos, significantly correlated with serum TSH receptor antibodies, an indicator for the disease activity of GO. ATD therapy significantly reduced RI in GD patients from 0.719+/-0.041 in the hyperthyroid state to 0.661+/-0.051 in the euthyroid state, but not to the levels observed in normal subjects having the similar exophthalmos (0.640+/-0.049). The fractional reduction of RI during ATD therapy significantly correlated with those of pulse pressure and ultrasonographic distensibility in carotid artery, but not with those of serum vascular injury markers. In 17 GD patients with clinically overt GO, all four patients having adipose tissue enlargement but not extraocular muscle hypertrophy (inactive GO) showed RI within the mean +/- 1 s.d. for treated GD patients without GO. In the other 13 GD patients having extraocular muscle hypertrophy (active GO), four and eight patients showed RI outside mean +/- 2 s.d. and mean +/- 1 s.d. respectively. Treatment with glucocorticoid plus radiation moved RI in 8 out of 10 patients toward the mean values of GD patients without GO, in spite of little improvement of exophthalmos. CONCLUSIONS: It was suggested that GD patients showed altered retinal hemodynamics, possibly resulting either from the cardiovascular effect of hyperthyroidism or from retro-orbital inflammation, particularly in extraocular muscle.     

Discordant hypothyroxinemia and hypertriiodothyroninemia in treated patients with hyperthyroid Graves' disease

Hypothyroxinemia and hypertriiodothyroninemia may occur in the course of antithyroid drug or 131I treatment for hyperthyroid Graves' disease. To determine the frequency of combined high serum T3 and low serum T4 concentrations during such treatment and to assess the clinical significance of its recognition, we reviewed 60 patients treated for hyperthyroid Graves' disease with antithyroid drugs (n = 43) or radioactive iodine (n = 17). Six of these patients (10%) were found to have high serum T3 and low serum T4 concentrations during therapy. Four were receiving antithyroid drugs, and 2 had received radioactive iodine. At the time this abnormality occurred, 4 patients were euthyroid, 1 was hypothyroid, and 1 was hyperthyroid. The serum TSH concentration was increased in 2, at the upper limit of normal in 1, and undetectable in 3 patients. In 2 clinically euthyroid patients, these biochemical findings resolved spontaneously. After discontinuation or reduction in the dose of antithyroid drug, clinical and chemical euthyroidism was restored in 2 additional patients with previously elevated TSH levels. In 2 patients, both of whom previously had undetectable serum TSH levels, clinical hyperthyroidism persisted or recurred, and additional therapy was required. No patient developed permanent hypothyroidism during the period of follow-up (1-22 months). An additional 19 of the 60 patients (32%) had an elevated serum T3 level with a normal serum T4 concentration during the course of follow-up. Among these 19 patients, the magnitude of serum T3 elevation was not different between clinically euthyroid (n = 13) and hyperthyroid (n = 6) patients. We conclude that discordance of serum T4 and T3 concentrations is frequently encountered in patients with hyperthyroid Graves' disease during or after therapy. In such patients, the low serum T4 level does not predict hypothyroidism, nor does a high serum T3 level predict hyperthyroidism. Furthermore, the serum T3 concentration in these patients correlates poorly with their clinical thyroid status.     

Serum antibodies to collagen XIII: a further good marker of active Graves' ophthalmopathy

OBJECTIVE: In Graves' ophthalmopathy (GO) intercellular adhesion molecule-1 (ICAM-1) is thought to play a key role in lymphocyte infiltration into the orbit, and serum levels of its soluble form are positively correlated to clinical activity score (CAS). Serum antibodies against collagen XIII (CollXIIIAb), a plasma membrane protein expressed at a low level in almost all connective tissue-producing cells, have been detected in GO, but their significance is unclear. The aim of this study was to search for CollXIIIAb in Graves' patients with and without ophthalmopathy and to correlate their levels with CAS and with serum soluble ICAM-1 (sICAM-1) values. PATIENTS: We studied 66 patients with Graves' disease whose sera had been previously tested for sICAM-1 levels, grouped as follows: 28 with moderate and active ophthalmopathy (group 1), 12 of them hyperthyroid (group 1a) and 16 euthyroid (group 1b); 13 with mild and inactive ophthalmopathy and normal thyroid function (group 2); 25 without ophthalmopathy (group 3), 11 of them hyperthyroid (group 3a) and 14 euthyroid (group 3b). Finally, 26 sera of normal controls were studied. MEASUREMENTs: CollXIIIAb were evaluated by an enzyme-linked immunosorbent assay (ELISA) method. RESULTS: In group 1 patients, CollXIIIAb were detected at high levels in 8/12 (66.6%) in group 1a [optical density (OD) ranging from 0.529 to 0.894] and in 10/16 (62.5%) in group 1b (OD 0.560-0.855). In group 2 patients, CollXIIIAb were detected but at low levels (OD 0.205-0.260) in 4/13 patients (30.7%). In group 3 patients, CollXIIIAb were present at low levels in 6/11 (54.5%) of group 3a and in 5/14 (35.7%) of group 3b (OD 0.215-0.290 and 0.144-0.245, respectively). CollXIIIAb were detected in only 4/26 normal controls (15%) but at low levels (OD 0.150-0.185). CollXIIIAb values in both groups 1a and 1b were significantly higher than those of the remaining groups. A positive correlation between CollXIIIAb levels and CAS but not thyroid hormone levels was found in groups 1a, 1b and 2. Moreover, a positive correlation between CollXIIIAb levels and sICAM-1-values was also evidenced in all three groups. CONCLUSIONS: Our results suggest that CollXIIIAb could be considered as a further good marker of active inflammatory processes involving the adipose connective tissue in GO. In particular, the high levels of CollXIIIAb in sera of Graves' patients with active ophthalmopathy could reflect an increased expression of type XIII collagen on the membrane of activated fibroblasts in these patients. Thus, the evaluation of these antibodies could be added to other known markers as a useful and inexpensive tool in monitoring Graves' patients and in modulating the treatment of GO.     

The mechanism of postoperative tetany in Graves' disease

The levels of serum calcium (Ca), inorganic phosphate (P) and mid-molecular parathyroid hormone (PTH) were measured in 37 patients with Graves' disease (12 in hyperthyroid state, 25 in euthyroid state followed by subtotal thyroidectomy), 6 with papillary carcinoma of the thyroid, 8 with benign nodular goiter and 19 healthy control subjects in order to investigate the change in these levels before and after thyroidectomy. The levels of serum Ca and P of the hyperthyroid patients with Graves' disease were 9.73 +/- 0.30 mg/dl and 4.47 +/- 0.44 mg/dl, respectively, which were significantly higher than those of healthy control subjects. No significant difference in the levels of serum PTH was observed between hyperthyroid patients with Graves' disease and healthy control subjects. The levels of serum Ca, P and PTH of euthyroid patients with Graves' disease were not significantly different from those of healthy control subjects. In the patients with Graves' disease who had undergone subtotal thyroidectomy followed by postoperative tetany, serum Ca and serum PTH decreased significantly from 9.39 +/- 0.45 mg/dl to 7.90 +/- 0.33 mg/dl and from 406.6 +/- 164.4 pg/ml to 229.9 +/- 136.0 pg/ml, respectively, after surgery, but there was no change in serum P. In the patients without postoperative tetany, serum Ca and serum P decreased significantly after surgery from 9.65 +/- 0.36 mg/dl to 9.15 +/- 0.33 mg/dl and from 4.03 +/- 0.46 mg/dl to 3.47 +/- 0.54 mg/dl, respectively, without any change in the levels of serum PTH. In the patients with papillary carcinoma or benign nodular goiter without postoperative tetany, the levels of serum Ca, P and PTH did not change after surgery. In the patients with papillary carcinoma followed by postoperative tetany, serum Ca decreased significantly after surgery with concomitant decrease of serum PTH. It was concluded that excessive thyroid hormones influenced Ca metabolism, and the transient tetany following subtotal thyroidectomy for Graves' disease seemed to be due to both the absorption of Ca by hungry bone and parathyroid hypofunction.     

Ratio of serum IgG3 to total IgG concentration and goiter size are independent factors in intractability of Graves' disease

Peripheral immunoglobulin (Ig) G(3)-secreting cells and serum concentrations of interleukin (IL)-10, a class-switching factor to IgG(3)-secreting cells, increase in patients with intractable Graves' disease (GD). However, they are not practical for laboratory tests. To find more stable and easily detectable markers of disease intractability or disease severity in patients with GD or Hashimoto's disease (HD), we examined the serum concentration of IgG(3) in 58 euthyroid GD patients who had been undergoing antithyroid drug treatment for more than 5 years but still must continue drug treatment to maintain a euthyroid state (intractable GD), 26 GD patients who had maintained a euthyroid state for more than 2 years without any treatment (GD in remission), 20 untreated, thyrotoxic GD patients, 40 euthyroid HD patients treated with thyroxine (5 men and 35 women), 13 untreated, euthyroid HD patients, and 39 healthy volunteers. Serum concentrations of IgG(3 )increased in euthyroid patients with intractable GD and in those with GD in remission, but serum concentrations of IgG were not altered. The ratio of serum concentrations of IgG(3) to total IgG (IgG(3)/IgG ratio) was higher in euthyroid patients with intractable GD than in those with GD in remission. Multiple logistic-regression analysis demonstrated that IgG(3)/IgG ratio and goiter size were independent factors in disease intractability of GD patients. These results suggest that IgG(3)/IgG ratio and goiter size may be used as independent markers associated with GD intractability.     

Interleukin-12B gene polymorphism does not confer susceptibility to Graves' ophthalmopathy in Japanese population

Graves' disease (GD) is an autoimmune disorder with genetic predisposition and frequently associated with Graves' ophthalmopathy (GO). Interleukin 12 (IL-12) is an important mediator of inflammatory immune responses and is expressed in the thyroid and orbit. IL-12B gene, which encodes the p40 subunit of IL-12, is located at chromosome 5q31-33. The aim of the present study was to investigate whether IL-12B gene polymorphism is associated with the development of GD or GO. IL-12B gene polymorphism was studied in Japanese GD patients (n = 329) and healthy control subjects without anti-thyroid autoantibodies or a family history of autoimmune disorders (n = 226). The A/C polymorphism at position 1188 of the 3' untranslated region (3'UTR) of the IL-12B gene was analyzed using the polymerase chain reaction--restriction fragment length polymorphism method. There was no difference in allele or genotype frequency of the IL-12B gene polymorphism (1188A/C) between GD patients and control subjects. There was no association of the IL-12B gene polymorphism with ophthalmopathy, severity of hyperthyroidism or serum IgE levels. There was no association of the IL-12B gene polymorphism with serum IL-12 levels, which were significantly elevated in hyperthyroid phase of GD. In conclusion, IL-12B gene 1188A/C polymorphism is not associated with GD or GO susceptibility in Japanese.     

Graves' ophthalmopathy and atrophic thyroiditis: a case report

Graves' ophthalmopathy (GO)--also known as thyroid-associated orbitopathy or ophthalmopathy--usually affects patients with Graves' disease. Antibodies stimulating the TSH receptor are thought to be involved in the pathogenesis of this important and disabling extra-thyroidal manifestation of Graves' disease. Less frequently, GO occurs in subjects who neither have nor have ever shown evidence of thyroid dysfunction ("euthyroid GO"), while the occurrence of GO in patients with autoimmune Hashimoto's thyroiditis is thought to be quite rare and has sporadically been reported. The late and abrupt occurrence of severe GO without hyperthyroidism in an 88-yr-old woman with primary myxedema due to atrophic thyroiditis must be considered as an exceptional event. In this patient, GO was combined with elevated titres of serum auto-antibodies directed against the TSH receptor, while serum levels of anti-thyroglobulin and thyroperoxidase antibodies were within the normal range or only occasionally slightly above the normal values.     

Prognostic role of adhesion molecules sELAM-1 and sICAM-1 in glucocorticoid therapy of active ophthalmopathy

Inflammatory process is connected with the increased expression on cells of adhesion molecules, also including intercellular adhesion molecule-1 (ICAM-1) and endothelial leukocyte adhesion molecule-1 (ELAM-1). In active ophthalmopathy (GO) this process, of various severity, is progressing in orbital tissue. This is reflected by the increase in blood of these molecules soluble forms. The aim of the project was to study sELAM-1 and sICAM-1 concentrations in sera of patients with GO in the course of Graves' disease (GD) gratified to glucocorticoid therapy, as well as the analysis of this treatment influence on both adhesion molecules with taking into consideration their prognostic role in an applied treatment. The analysis included 25 subjects with eye changes in the class at least 2c (ATA). The duration of GO did not exceed 2 years. Patients received 3 i.v. "pulses" of methyloprednisolone (1 g/d, every second day), followed by oral administration of prednisone during 3 months (60 mg/d, with gradual dose reduction). The blood was taken before treatment, next day after the last methyloprednisolone infusion, after 2 week of prednisone therapy and after completing of glucocorticoid treatment. As a result of the applied therapy 15 subjects obtained clinical improvement (group 1A), on the contrary 10 persons did not gain positive effects after finishing prednisone (group 1B). Before starting the treatment sICAM-1 and sELAM-1 levels in group 1A were lower than those in group 1B. After methyloprednisolone therapy sICAM-1 and sELAM-1 concentrations declined in both groups. This was related in the most of patients to clinical improvement, which occurred at that time. After 2 weeks of prednisone application concentrations of both adhesion molecules were still decreased. After completing of glucocorticoid therapy in patients with clinical improvement (group 1A) sICAM-1 concentration remained suppressed, in the range of concentrations present in sera of healthy subjects (group 2). In patients without clinical response (group 1A), with gradual recurrence of inflammatory symptoms together with reduction of prednisone dose sICAM-1 concentration increased again to values comparable to initial levels. sELAM-1 concentration in group 1A still did not markedly change after completing of glucocorticoid therapy, on the contrary--in group 1B the level of this adhesion molecule slightly increased. These values, in contradistinction to sICAM-1, did not drop during therapy to concentrations characteristic for normal range. According to the results it may be concluded, that clinical improvement after glucocorticoid therapy is connected with lower adhesion molecules concentrations before treatment. Glucocorticosteroids are causing decrease of sICAM-1 and sELAM-1 concentrations in patients with GO in the grade dependent on the dose of medication, on the contrary changes in sELAM-1 concentration are less significant. Maintenance of decreased sICAM-1 concentration during glucorticoid therapy is a positive prognostic factor.     

Clinical utility of red blood cell carbonic anhydrase I and zinc concentrations in patients with thyroid diseases

We have recently reported that, in patients with hyperthyroidism, the red blood cell (RBC) carbonic anhydrase I (CAI) and zinc (Zn) concentrations both reflect the patient's integrated thyroid hormone level over the preceding few months. In this study, we evaluated the clinical usefulness of determining the RBC CAI and Zn concentrations in patients with various types of thyroid disease. Six patients with painless thyroiditis (PT) had normal RBC CAI concentrations and the two patients tested had normal RBC Zn levels. In four patients with syndromes of inappropriate thyrotropin (TSH) secretion (SITSH) two euthyroid patients had normal RBC CAI and two hyperthyroid patients had subnormal RBC CAI and Zn. In a patient with Graves' disease whose plasma thyroxine (T4) and triiodothyronine (T3) concentrations changed remarkably because of poor compliance with the regimen, the change in plasma thyroid hormone levels preceded the change in the RBC CAI and Zn concentrations by 2 to 3 months. These observations suggest that the measurement of RBC CAI and Zn concentrations may be useful clinically as follows: (1) in differentiating hyperthyroid Graves' disease from transient hyperthyroidism due to destructive thyroiditis; and (2) in obtaining an accurate estimate of the extent of elevated thyroid hormone levels in hyperthyroid patients over time.     

Clinical studies on abnormal thyroid stimulators in patients with Graves' disease. II. Clinical significance of measuring TSAb and TBII in patients with euthyroid Graves' disease and patients with hyperthyroid Graves' disease during antithyroid drug treatment

To evaluate the clinical significance of TBII and TSAb activities in euthyroid and hyperthyroid Graves' disease, these two activities were measured in 8 patients with euthyroid Graves' disease and 29 patients with hyperthyroid Graves' disease during treatment with antithyroid drugs. In 8 patients with euthyroid Graves' disease, TBII activity was detectable only in one patient and TSAb activity detected in 3 patients, these detectabilities being much lower than those in hyperthyroid Graves' disease. However, 2 of 4 patients who had either TSAb or TBII came to have both activities, and one of them became overt hyperthyroid. In patients with hyperthyroid Graves' disease, detectabilities of these activities became lower as they became euthyroid with antithyroid drug treatment, but TSAb tended to be higher than TBII when they remained euthyroid for more than 4 months. Although the majority of the patients who had TSAb and/or TBII activities were T3 non-suppressible, patients with no TSAb and TBII activities did not necessarily show remission of the disease. The present results suggest that patients with euthyroid Graves' disease with both TBII and TSAb may be apt to become hyperthyroid, and that TSAb and TBII activities and T3 suppressibility may not be a definite criteria for the remission of Graves' disease.     

A possible role of immunoglobulin E in patients with hyperthyroid Graves' disease.

To investigate the possible participation of immunoglobulin E (IgE) in the autoimmune process of Graves' disease, incidence of elevation of serum IgE level, TSH receptor antibody (TRAb), and thyroid status were studied in 66 patients with hyperthyroid Graves' disease, 54 patients with Hashimoto's thyroiditis, 19 patients with bronchial asthma, and 15 patients with pollen allergy. In hyperthyroid Graves' patients, elevation of serum IgE levels (> or = 170 U/mL) was found in 19 of 66 patients (29%), 11 of whom had hereditary and/or allergic conditions. Elevations of serum IgE levels were found in 63% of patients with bronchial asthma and in 40% of patients with pollen allergy. Mean values of serum IgE were the same in patients with hyperthyroid Graves' disease and with bronchial asthma. During methimazole treatment TRAb decreased without fluctuation of IgE levels in both groups. The decrease in TRAb was significantly greater in patients with normal IgE than in patients with IgE elevation. After prednisone administration, reduction in TRAb was greater in patients with normal IgE than that in patients with IgE elevation. High incidence of IgE elevation in hyperthyroid Graves' disease and slower reduction in TRAb in association with IgE elevation suggest a difference in the autoimmune processes in Graves' disease with and without elevation of IgE.     

Serum thyrotropin receptor antibodies concentrations in patients with Graves' disease before, at the end of methimazole treatment, and after drug withdrawal: evidence that the activity of thyrotropin receptor antibody and/or thyroid response modify during the observation period.

AIM AND METHODS: We performed a quantitative retrospective analysis of serum thyrotropin receptor antibody (TRAb) concentrations measured by a second-generation radioreceptor assay in 58 patients with Graves' disease (GD) at the onset of the disease, at the end of 18 month methimazole (MMI) treatment, and after MMI withdrawal in order to evaluate the correlation between the presence of these antibodies and the relapse of hyperthyroidism. Sixty healthy subjects were enrolled as a control group. RESULTS: Before MMI treatment the best cutoff TRAb value for identifying patients with GD was 1.45 UI/L (specificity, 100%; sensitivity, 98.3%). At the end of MMI treatment, serum TRAb concentrations were significantly lower (p < 0.001) than those measured at baseline, but they were still significantly higher (p < 0.001) than those found in the control subjects. At the end of MMI treatment, 44 patients (75.9%) had positive TRAb values (>1.45 UI/L). After MMI withdrawal (median, 15 months), 34 patients (58.6%) became hyperthyroid, 4 patients (6.9%) became hypothyroid, and 20 patients (34.5%) remained euthyroid. There was a significant correlation between serum TRAb concentrations at the end of MMI treatment and the percentage of patients who became hyperthyroid (r: 0.56; p < 0.001) and the time of appearance of hyperthyroidism (r: -0.38; p = 0.03). All 4 patients with TRAb values below 0.9 UI/L at the end of MMI treatment remained euthyroid throughout the follow-up period. Among the 27 patients who had serum TRAb values higher than 4.4 UI/L, 23 developed hyperthyroidism and 4 hypothyroidism. The TRAb values between 0.9 and 4.4 UI/L did not discriminate between the 27 patients (46.6%) who remained euthyroid from those who had relapse of hyperthyroidism. Thus a different TRAb end of treatment cutoff was calculated to identify patients who became again hyperthyroid. This TRAb cutoff value was 3.85 UI/L (sensitivity, 85.3%; specificity, 96.5%). All but 1 patient who had serum TRAb values above 3.85 UI/L became hyperthyroid after MMI was withdrawn (positive predictive value, 96.7%). In these patients, relapse of hyperthyroidism was independent of the changes in serum TRAb concentrations (r: 0.27; p = 0.15) and occurred after a median period of 8 weeks (range, 4-48). Hyperthyroidism also developed in 5 of 24 patients who had serum TRAb concentrations lower than 3.85 UI/L at the end of MMI treatment. In these 5 patients the relapse of hyperthyroidism occurred after a median period of 56 weeks (range, 24-120) and was always accompanied by an increase in serum TRAb concentrations. CONCLUSIONS: TRAb persist in the blood of most patients with GD after 18 months of MMI treatment. Both the frequency and the time of appearance of hyperthyroidism are closely correlated with serum TRAb concentrations at the end of MMI treatment. Our data would suggest that TRAb maintain stimulating activity after a full course of MMI treatment in the large majority of patients with GD. However, it is likely that the potency of these antibodies and/or the thyroid response to them change during treatment, as suggested by the different values measured in euthyroid control subjects and in euthyroid patients after MMI treatment.     

Increase of interferon-gamma-inducible CXC chemokine CXCL10 serum levels in patients with active Graves' disease, and modulation by methimazole therapy

BACKGROUND: CXCL10 plays an important role in the initial phases of Graves' disease (GD) and autoimmune thyroiditis (AT); however, until now, CXCL10 serum levels (sCXCL10) in patients with GD have never been evaluated in relation to thyroid function and treatment. OBJECTIVE: To evaluate sCXCL10 in GD. DESIGN: Cross-sectional. PATIENTS: One hundred and three GD, 164 AT, 20 nontoxic multinodular goitre (NTMNG), 16 toxic nodular goitre (TNG) patients and 70 healthy controls (age- and sex-matched). MEASUREMENTS: We measured sCXCL10 in patients and controls, to relate this parameter to the clinical phenotype. RESULTS: Mean sCXCL10 in GD and AT patients were comparable (122+/-81 and 133+/-102 pg/ml) and significantly higher (P<0.01) than in controls or NTMNG patients (73+/- 32 and 76+/- 25 pg/ml, respectively). Hyperthyroid GD had significantly higher sCXCL10 than euthyroid or hypothyroid GD (145+/- 92, 107+/- 56 and 105+/- 46 pg/ml, respectively; P=0.01). GD patients with untreated hyperthyroidism had higher sCXCL10 than hyperthyroid or euthyroid GD patients under methimazole (MMI) treatment (166+/-125, 124+/- 41 and 94+/- 35 pg/ml, respectively; P=0.006). Comparable sCXCL10 levels were observed in newly diagnosed untreated hyperthyroid GD patients with respect to untreated patients with relapse of hyperthyroidism after a previous MMI course (176+/-125, 155+/- 97 pg/ml, respectively). GD had similar sCXCL10 to AT and higher than TNG patients or controls (all age- and sex-matched) (144+/- 81, 149+/- 114, 101+/- 27 and 86+/- 44 pg/ml, respectively; P=0.02). CONCLUSIONS: sCXCL10 is associated with the active phase of GD in both newly diagnosed and relapsing hyperthyroid patients. The reduction in sCXCL10 in treated patients with GD may be related to the immunomodulatory effects of MMI.     

Circulating soluble interleukin 2 receptor concentration is increased in both immunogenic and nonimmunogenic hyperthyroidism.

High serum concentration of soluble interleukin-2 receptor (sIL-2R) is considered a reliable marker of T lymphocyte activation. It has been recently reported that sIL-2R levels are increased in untreated Graves' disease. This finding has been interpreted as the consequence of an active autoimmune state, but the relevance of the thyroid function per se was not investigated. In the present study we assayed sIL-2R by ELISA in 20 normal subjects and in a series of patients with immunogenic (Graves' disease, GD) or nonimmunogenic (toxic adenoma, TA) hyperthyroidism. Significant increased concentrations of sIL-2R were found in 46 patients with untreated hyperthyroid GD (mean +/- SD: 1,683 +/- 1016 U/ml, vs 461 +/- 186 U/ml in normal controls, p less than 0.0001) and in 21 with untreated TA (1,111 +/- 617 U/ml, p less than 0.0001 vs normals). Restoration of the euthyroid state by antithyroid drugs or 131I administration was associated with a normalization of sIL-2R (516 +/- 174 U/ml in 38 patients with GD and 365 +/- 90 U/ml in 12 with TA; p = NS vs normals and p less than 0.001 vs the untreated state for both groups). A highly significant positive correlation between serum sIL-2R and free triiodothyronine (FT3) (r = 0.724, p less than 0.0001) or free thyroxine (FT4) (r = 0.698, p less than 0.0001) concentrations was found in combined sera obtained from all untreated and treated patients, irrespectively of the autoimmune or nonautoimmune nature of the underlying hyperthyroid disease.(ABSTRACT TRUNCATED AT 250 WORDS)     

The possible contribution of anti-Gal to Graves' disease.

Anti-Gal is a natural antibody specific for the alpha-galactosyl epitope. Previous studies suggested that Graves' disease (GD) patients had elevated anti-Gal titers compared to normal controls, but titers returned to normal after treatment. We developed an anti-Gal enzyme-linked immunosorbent assay (ELISA) using the property of anti-Gal to bind tightly to mouse laminin. We found no significant correlations between anti-Gal and thyroidstimulating immunoglobulin (TSI) or free thyroxine (T(4)) in untreated hyperthyroid GD patients (n = 15) without clinical ophthalmopathy or euthyroid, previously treated GD patients with ophthalmopathy. There was a significant regression between TSI and free T(4) in the hyperthyroid patients (p < 0.01). Addition of total anti- Gal antibody to the regression showed a trend toward improved correlation (p = 0.15 for improved correlation relative to TSI and free T(4) alone), suggesting it may stimulate GD thyroid tissue. However, in contrast to previous studies we found hyperthyroid patients (n = 20) had lower levels of anti-Gal immunoglobulin G (IgG) (18.4 +/- 4.0 vs. 41.8 +/- 8.9) than normals (n = 36 p < 0.05). Interestingly, hyperthyroid patients without clinical ophthalmopathy tended to have lower IgG anti-Gal levels than euthyroid patients with ophthalmopathy (p = 0.1). Hyperthyroidism significantly lowers anti-Gal, but the possible increase of anti-Gal in patients with ophthalmopathy suggests anti-Gal may play a role in ophthalmopathy, or may reflect the euthryoid status of these patients. This trend needs further study.     

SINGLE DAILY DOSE SHORT TERM CARBIMAZOLE THERAPY FOR HYPERTHYROID GRAVES''DISEASE

Twenty-one patients with hyperthyroid Graves' disease were treated with carbimazole 30 mg daily, given as a single dose. Propranolol was also given for the first 3 weeks. All became clinically euthyroid with normal serum thyroxine (T4) levels, usually within 1-3 months. Patients with large goitres and raised serum alkaline phosphatase concentrations took longer to respond. In 19 patients a positive thyroid stimulating hormone (TSH) response to intravenous thyrotrophin releasing hormone (TRH) developed. Carbimazole was stopped soon after (median time of treatment 18 weeks, range 9-41 weeks) and 18 patients have been followed. Seven of these (39%) have remained in remission from hyperthyroidism for more than one year (median 77 weeks). Carbimazole 30 mg once daily is a convenient and effective treatment for hyperthyroid Graves' disease. Many patients will achieve prolonged remissions if treatment is stopped when serum T3 and T4 levels are in the low-normal range, usually 2-4 months after clinical euthyroidism has been reached.     

STUDIES ON THYROTROPHIN RECEPTOR ANTIBODIES IN PATIENTS WITH EUTHYROID GRAVES'' DISEASE

Thyroid stimulating antibodies (TSAb) and TSH-binding inhibitor immunoglobulins (TBII) were assessed in 30 patients with euthyroid Graves' disease. TSAb were detected in 24 cases (80.0%), the incidence being not significantly different from that in hyperthyroid Graves' disease (29/30, 97.6%). On the other hand, the incidence of TBII in patients with euthyroid Graves' disease (12/30, 40.0%) was significantly lower than that in patients with hyperthyroid Graves' disease (30/30, 100.0%). The mean TSAb and TBII activities in the euthyroid patients were significantly lower than in the hyperthyroid patients (P less than 0.005 and P less than 0.001, respectively). Both TBII and, more closely, TSAb activities correlated with T3-nonsuppressibility and inhibition of serum TSH response to TRH stimulation. The findings supported the stimulation in vivo of the thyroid by these antibodies. Both antithyroglobulin and antimicrosomal antibody titres in euthyroid Graves' disease were significantly lower than in hyperthyroid Graves' disease (P less than 0.05, P less than 0.01, respectively). Goitre size was significantly smaller (P less than 0.001), and 99mTc thyroid uptake was significantly lower (P less than 0.001) in the euthyroid than in the hyperthyroid group. Thus, the reduced mass of thyroid tissues responding to the stimulators was considered to be one of the factors responsible for the euthyroidism despite the presence of TSAb. The high incidence of TSAb and relatively low incidence of TBII in euthyroid Graves' disease indicate that the presence of TSAb does not necessarily lead to hyperthyroidism and that the development of overt thyrotoxicosis may require augmentation of both TSAb and TBII.     

DEPRESSED NATURAL KILLER ACTIVITY IN GRAVES'' DISEASE AND DURING ANTITHYROID MEDICATION

To investigate the natural killer (NK) cell mediated immunity in Graves' disease (GD) and the effect of antithyroid drugs upon NK cell activity, 51Cr release assay for NK cytotoxicity against K562 cells was examined in patients with GD before and during antithyroid medication and after drug withdrawal. Fifty-eight patients were divided into three groups: the untreated thyrotoxic patients (n = 33), the euthyroid patients under antithyroid treatment (n = 19) and the euthyroid patients after drug withdrawal (n = 6). The results of the three groups were compared to 23, 15 and 5 sex- and age-matched controls, respectively. The data revealed a significant NK dysfunction in the untreated hyperthyroid patients, although the number of the NK cells was not decreased. NK function was normal when patients were no longer taking antithyroid medication and in euthyroid state. However, euthyroid patients under antithyroid medication had markedly depressed NK activity, suggesting an immunosuppressive effect of the antithyroid drugs. This study demonstrated that both the hyperthyroid state and the antithyroid drugs exerted immunosuppressive effects upon the NK cells. Since such an immunosuppressive effect on NK cells might be associated with a decreased immune surveillance against tumour growth, this study implies that a long-term follow up of GD patients treated with antithyroid drugs may be indicated to guard against a possible increased incidence of malignancy.