Improvement of immunologic abnormalities associated with hyperthyroidism of Graves' disease during methimazole treatment

In an attempt to study the effects of methimazole treatment on immunologic abnormality of hyperthyroidism of Graves' disease, TSH receptor antibody (TRab), anti-DNA antibody and HLA-DR were measured in untreated patients with hyperthyroidism of Graves' disease and treated patients with methimazole for 2 years, using peripheral blood. In untreated patients, all 3 parameters elevated above normal. Three parameters decreased 2 years after methimazole treatment, but the magnitude of decrease was more in T3-suppressible patients than in T3-unsuppressible patients. However, both anti-DNA antibody and HLA-DR were significantly more in T3-suppressible patients than in normal subjects. It is suggested that immunologic abnormalities should largely be improved before remission of Graves' disease can be obtained.     

Thyrotropin receptor non-mediated thyroid stimulating immunoglobulin in Graves' disease.

There exists a consensus that hyperthyroid Graves' disease is caused by thyrotropin receptor (TSH-R) autoantibodies. To test the possibility that the TSH-R is the sole antigen for thyroid stimulating antibodies (TSAb), we compared bioactivities of Graves' IgGs between non-thyroid mammalian cells transfected with human TSH-R cDNA and the reference thyroid bioassay. A Graves' IgG with TSH-binding inhibitor immunoglobulin (TBII) activity (89%) markedly stimulated cAMP formation in both CHO-K1 cells transfected with TSH-R cDNA (340 microU/ml of TSH equivalent) and rat thyroid cells, FRTL-5, (410 microU/ml of TSH equivalent). In contrast, a TBII negative (-1.5%) IgG from another patient with Graves' disease showed a strong thyroid stimulating activity (87 microU/ml of TSH equivalent) when FRTL-5 cells were used for the assay. But no stimulating activity was observed in this IgG when CHO-K1 cells transfected with TSH-R cDNA were used, suggesting a possible existence of TSH-R non-mediated thyroid stimulating immunoglobulin in some cases of Graves' disease.     

Serum free thyroid hormones are decreased by betamethasone treatment in Graves' disease

38 patients with Graves' disease were treated at random with the glucocorticosteroid betamethasone or with placebo. The daily oral dose was 6.0 mg for the first 5 days, 4.5 mg for the following week, and then 3.0 mg. The serum free triiodothyronine (FT3) concentration decreased within 5 days, while the free thyroxine (FT4) level was reduced first after 3 weeks of betamethasone treatment. The suppressed serum thyrotropin concentration did not change. In the placebo group no significant constant alterations were found in any of the variables studied. The results corroborate that betamethasone decreases FT3 and to a less degree also FT4, which earlier has been indicated by indirect methods, although the mechanisms behind the changes remain to be clarified. Since FT3 is more readily available for the metabolic effects in tissues the rapid striking fall in its concentration is an argument for glucocorticoid treatment in selected patients with severe hyperthyroidism of Graves' disease.     

Prediction of the outcome of postoperative hypocalcemia in Graves' disease.

Symptomatic hypocalcemia sometimes follows subtotal thyroidectomy for Graves' disease. Irreversible damage to the parathyroids contributes to permanent hypocalcemia and the mechanism for a transient hypocalcemia is thought to be different from that of a permanent one. However, sensitive assays for parathyroid hormones (PTH), which had recently become available, revealed that levels of PTH decrease in patients with transient hypocalcemia. In order to differentiate a prolonged hypocalcemia from a transient one, calcium and inorganic phosphate concentrations in serum as well as in urine, and whole molecule-PTH levels were determined in 18 Graves' disease patients with postoperative hypocalcemia just after the initial symptoms for hypocalcemia appeared. In 13 patients, medication was withdrawn within one month since serum calcium levels had returned to normal (transient hypocalcemia). In five other patients, medication was required for six months or more to maintain normocalcemia (prolonged hypocalcemia). The same parameters were determined after surgery in eight Graves' disease patients without hypocalcemia. Urinary inorganic phosphate concentrations in patients with prolonged hypocalcemia (0.02 +/- 0.01 mmol/mmol Cr) were significantly lower (P less than 0.01) than those in patients with transient hypocalcemia (1.59 +/- 1.59 mmol/mmol Cr) or those in control patients (1.27 +/- 0.70 mmol/mmol Cr). Preoperative concentrations of calcium and inorganic phosphate in serum and urine, and serum alkaline-phosphatase activities were also determined. However, there were no significant differences in these parameters between patients with prolonged and those with transient hypocalcemia. It is concluded that prolonged hypocalcemia is discriminated from the transient type by determining the urinary inorganic phosphate at the time of appearance of the initial symptoms for hypocalcemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Levels of autoantibodies against human TSH receptor predict relapse of hyperthyroidism in Graves' disease.

The aim of this study was to evaluate the ability of the more sensitive second-generation TSH receptor (TRAb) assay to predict recurrent Graves' disease (GD) vs. remission depending on TRAb levels. 93 patients with active GD were included in the study. By using a cut-off limit of 1.0 IU/l, all 93 patients were positive for TRAb (median: 4.6 IU/l) at the time of their first visit (single point measurement in median 5.1 months after initial diagnosis). Subsequently, 33 patients went into remission and were euthyroid during follow-up (median follow-up: 21.7 months), whereas 60 patients did not go into remission or developed relapse over the following 24 months. Median TRAb levels in the group of remission were significantly (p < 0.0001) lower than TRAb values in the relapse group (2.1 compared to 8.6 IU/l). Applying ROC plot analysis to compare different TRAb thresholds, a cut-off of 10 IU/l was established. Here, the specificity for relapse was 97 % as only 1 of 29 patients with TRAb values above 10 IU/l went into remission during follow-up, whereas all other 28 patients developed a relapse (positive predictive value for relapse: 96.4 %). In contrast, TRAb values lower than 10 IU/l had no impact on the prediction of remission. In conclusion, our data clearly indicate that TRAb measurement is useful for identifying patients that will not benefit from long-term antithyroid drug treatment.     

Signaling pathways involved in thyroid hyperfunction and growth in Graves' disease.

The elucidation of the multiple signaling cascades coupled to the TSH receptor has offered new approaches in the understanding of the pathogenesis of Graves' disease. Here we review findings showing that immunoglobulins from Graves' patients are heterogeneous, bind to different epitopes and, similarly to TSH, activate different signaling pathways, including adenylyl cyclase, phospholipase C and phospholipase A2. Evidence that the multiplicity of signals correlates with the different manifestations of the disease is also summarized. We believe that the dissection of the molecular mechanisms involved in the pathogenesis of Graves' disease offers the basis for developing novel therapeutical approaches to this disease.     

Thyrotropin receptor antibody activities significantly correlate with the outcome of radioiodine (131I) therapy for hyperthyroid Graves' disease.

The outcome of 131I therapy for 109 patients with Graves' disease was analysed according to pretreatment laboratory data including thyrotropin receptor antibody (TRAb) activities. Forty-five percent of patients became euthyroid, and 13% of patients became hypothyroid within one year after 131I therapy. Forty-two percent of patients remained hyperthyroid one year after 131I therapy. Pretreatment values for serum T4, T3, and the estimated weight of the thyroid were significantly higher in the hyperthyroid group. The mean for the TRAb index of the hyperthyroid group was significantly higher than that of the euthyroid group. Life table analysis revealed a significant effect of the TRAb index on the rate of hyperthyroidism after 3 months or later. These results appear to suggest that the TRAb index is one of the factors which influence the outcome of 131I therapy for Graves' disease.     

Suppression of thyroid cell growth by serum IgG in Graves' disease.

To determine whether serum immunoglobulin in addition to epidermal growth factor (EGF) augment growth in human thyroid cells, effects of these factors on thyrocytes were tested using IgG derived from 34 patients with Graves' disease and 12 normal subjects. The cell growth was estimated by [3H]-thymidine uptake, cell cycle determined by FACS analysis and the expression of c-fos mRNA in monolayer thyrocytes enzymatically prepared from Graves' thyroid. The addition of IgG taken from patients with Graves' disease inhibited the [3H]-thymidine uptake compared to that taken from control subjects. IgG taken from Graves' disease suppressed EGF-induced increase of S + G2/M phase in cell cycle and the expression of c-fos mRNA, while those taken from normal subjects did not affect at all. [3H]-thymidine uptake was more suppressed by IgG from patients with a smaller-sized goiter than by those with a larger-sized one. There was a negative correlation between the suppression of [3H]-thymidine uptake and levels of TBII (p less than 0.05). There was no correlation between the degree of suppression and the levels of T3, T4, TSAb, TSBAb or MCHA. Thus, in conclusion, IgG derived from sera of Graves' may inhibit the growth of Graves' thyrocytes, leading to the determination of the goiter size.     

The influence of hyperthyroidism and glucocorticosteroid treatment on bone metabolism in patients with Graves' disease and ophthalmopathy

The aim of the study was to assess influence of hyperthyroidism and glucocorticosteroid treatment on changes of bone turnover markers in patients with Graves' disease and thyroid ophthalmopathy (TO). MATERIAL AND METHODS: Three groups of patients were included in the study. Group I was composed of 26 euthyroid Graves' disease patients with TO suitable for steroid treatment. Group II included 14 hyperthyroid Graves' patients without TO treated medically with anti-thyroid drugs. Group III (control group) included 20 healthy volunteers. Levels of the bone formation marker, i.e. bone-specific alkaline phosphatase (BALP) and the bone resorption marker, i.e. deoxypyridinoline (DPD) were measured in the group I before steroid treatment administration, after 3 methylprednisolone i.v. pulses and after completing the oral prednisone treatment. In the group II levels of BALP and DPD were assessed twice: before treatment of hyperthyroidism and after 6 months since euthyroid state had been achieved. In the group III levels of BALP and DPD were measured once in the basal conditions. RESULTS: Mean initial levels of BALP in groups I and II did not differ significantly and were increased when compared to healthy volunteers. In the group I a transient significant decrease in BALP levels after 3 i.v. pulses of methylprednisolone was observed, followed by a significant increase in BALP after completing the oral prednisone therapy. The achievement of euthyroid state in Graves' patients (II) did not influence significantly BALP values. In the group I initial DPD levels were significantly lower than those in group II and higher than those in the control group (III). During steroid treatment of TO (group I) no dynamic changes of DPD levels were observed. The achievement of euthyroid state in group II was accompanied by a significant decrease in DPD levels, which were however than those in the control group. CONCLUSIONS: 1. In hyperthyroid state is associated with the profound stimulation of bone resorption, and to a lesser extent of bone formation. 2. The achievement of euthyroid state causes a rapid inhibition of bone resorption and maintains a compensatory stimulation of bone formation. 3. Glucocorticosteroid treatment with methylprednisolone i.v. pulses and orally administered prednisone do not influence significantly the processes of bone formation and bone resorption.     

Graves' hyperthyroidism following primary hypothyroidism due to Hashimoto's thyroiditis in a case of thyroid hemiagenesis: case report

Thyroid hemiagenesis (TH) is a rare inborn anomaly, resulting from failure of one thyroid lobe development. It is usually detected incidentally during investigation of concomitant thyroid disorders. The reported patient first presented hypothyroidism at the age of 49, when Hashimoto's thyroiditis (HT) and left thyroid lobe agenesis was diagnosed. L-thyroxine (LT4) replacement therapy restored hormonal balance. Two years later, the patient developed features of Graves' hyperthyroidism. The antithyroid pharmacotherapy by thiamazole was used. However, due to severe side-effects it was discontinued, and radioiodine treatment was applied. Four months after 131I administration, symptoms of hypothyroidism appeared, so thyroid hormone substitution was reintroduced. The patient, whose observation period has now reached 5 years, under LT4 replacement therapy, remains both clinically and biochemically euthyroid. The described case displays a very rare coincidence of hypothyroidism due to HT converted into Graves' hyperthyroidism, accompanying TH. Each of these three entities, may influence the thyroid function in a different way, hence, systematic follow-up and individual therapeutic management is required.     

Telangiectasia as a presenting sign of Graves' disease

Acquired nevoid telangiectasia (ANT) is observed in several conditions including primary cutaneous disorders, systemic autoimmune disease and hyperestrogenism occurring in puberty, pregnancy and chronic liver disease. We describe a patient in whom ANT was a presenting sign of autoimmune hyperthyroidism, which improved after thyroidectomy. A 43-year-old Caucasian woman experienced an asymptomatic development of multiple widespread red skin lesions, diagnosed to be ANT. Blood tests revealed increased serum levels of free tri-iodothyronine and thyroxine and suppressed thyroid-stimulating hormone. Other causes of ANT were excluded. ANT improved but did not disappear after thyroidectomy. The possible pathogenetic factors linking ANT and Graves' disease, such as an immune-mediated process, altered estrogen metabolism or vasodilatation associated with hyperdynamic circulation, are discussed.     

The management of hyperthyroidism due to Graves' disease in Japan in 1988. The Japan Thyroid Association

The management of hyperthyroidism due to Graves' disease in Japan was the subject of a survey of the members of the Japan Thyroid Association (JTA), and the results were compared to those of the European Thyroid Association (ETA). In the questionnaire, in vivo and in vitro diagnostic procedures, the choice of treatment and the details of the treatment for a patient with typical, moderate and uncomplicated hyperthyroidism due to Graves' disease was at first asked, and eight variations with a single alternative were proposed to evaluate how each alternative would affect the choice of treatment. For the diagnostic procedures, thyroid uptake/scintigraphy was carried out by approximately 60% of the respondents and the isotope mainly used was 123I. The number of in vitro tests used for diagnosis averaged 8.1 +/- 1.8 tests. Measurements of basal TSH and free T4 were the most frequent tests performed to confirm the diagnosis of hyperthyroidism (94 and 80%, respectively). Determinations of microsomal, thyroglobulin and TSH-receptor autoantibodies were also employed by many respondents (96, 96 and 77%, respectively). On the other hand, the free T4 index and TRH test were less frequently employed. In the treatment of these patients, antithyroid drug treatment was the first choice, and surgery was not, in general, regarded as a primary therapy except in a patient with a large goiter. The frequency of the respondents who advocated radioiodine therapy was considerably higher for patients with recurrences and old age. No respondents proposed radioiodine therapy for young patients. Specialists tended to favor their own specialist treatment regimens. The initial dose of antithyroid drugs was reduced according to thyroid function, and withdrawal of antithyroid drug treatment was determined by some specific criteria (basal TSH in supersensitive assays, TSH-receptor autoantibodies, T3 suppression test, etc.). The aim of radioiodine therapy and surgery was to restore euthyroidism. The significant differences between the results from the JTA and those from the ETA were as follows; radionuclide used for thyroid uptake/scintigraphy was mainly 123I in Japan, but 131I in Europe, the number of diagnostic studies in Japan was more than that in Europe, and the dosage of antithyroid drugs was reduced according to thyroid function and discontinued based on certain specific criteria in Japan, but after fixed periods in Europe. These results may represent actual trends in how hyperthyroidism due to Graves' disease is managed in specialist clinics in Japan today and the differences between the JTA and the ETA.     

Primary malignant lymphoma of the thyroid in a patient with long-standing Graves' disease

We have recently encountered a patient with rapidly enlarging thyroid masses histologically diagnosed as diffuse histiocytic lymphoma which developed in the active course of Graves' disease. The primary thyroid lymphoma has been in complete remission after local radiation therapy. The association of Hashimoto's thyroiditis and thyroid lymphoma has well been recognized. Meanwhile, data have accumulated to demonstrate that Hashimoto's thyroiditis and Graves' disease share possible similar causal immunological abnormalities and are closely related entities. However, the association of Graves' disease and primary thyroid lymphoma has never been reported, as far as we know. Therefore, this case may be the first one that supports the natural concept that thyroid lymphoma develops from pre-existing Graves' disease secondary to the similar immunological abnormalities in Hashimoto's thyroiditis.     

A singular case of Graves' disease in congenital thyroid hemiagenesis

We report the observation of an unusual case of Graves' disease associated with thyroid hemiagenesis. A 41-year-old woman who presented with symptoms and clinical signs of hyperthyroidism was discovered to have thyroid hemiagenesia of the left lobe. Thyroid ultrasound scan showed enlargement of the right lobe with a single nodule, and absence of the left lobe; isotope scan showed homogeneous uptake in the single lobe and nodule. Ophthalmopathy, which was absent at presentation, developed after two years; after a further 2 years the patient developed decompensated hypothyroidism requiring thyroxine replacement. This is the first case of Graves' disease in thyroid hemiagenesis evolved to hypothyroidism, and a rare case of thyroid ophthalmopathy accompanying this condition.     

Optimum duration of antithyroid drug treatment determined by assay of thyroid stimulating antibody in patients with Graves' disease.

OBJECTIVE--To determine the optimal duration of antithyroid drug treatment by monitoring serum thyroid stimulating antibody values in patients with Graves'' disease. DESIGN--Prospective longitudinal trial of patients with Graves'' disease followed up for 24 months after withdrawal of treatment. SETTING--Tertiary referral centre. PATIENTS--A total of 64 consecutive patients with untreated Graves'' disease, eight of whom were subsequently excluded. Fifty six patients completed the study. INTERVENTIONS--All patients were treated initially with carbimazole 40 mg, then with decreasing doses that maintained a euthyroid state. Treatment was scheduled to continue for 18 months but was withdrawn earlier if serum thyroid stimulating antibody became undetectable. END POINT--Serum values of thyroid stimulating antibody (assayed by stimulation of human thyroid cells in vitro) and thyroid hormones and thyroid state every three months during treatment and afterwards every six months for 24 months. MEASUREMENTS AND MAIN RESULTS--In 44 patients serum thyroid stimulating antibody became undetectable during treatment and treatment was withdrawn (median duration of treatment nine months, range 3-18 months). In 12 patients the antibody could be detected during 18 months of treatment. Among the first group of 44 patients initial values of the antibody before treatment were significantly lower than in the second group of 12 patients (median 225% (range 138-1236%) v 570% (250-1480%), p less than 0.001); the incidence of relapse was also lower (41% v 92%, p less than 0.001); and among those who did relapse the disease free interval after treatment was longer (median 12 months v 1 month, p less than 0.001). Moreover, the initial median serum values of thyroid stimulating antibodies were not related to the occurrence of relapse or remission as these did not differ between patients who did and did not have a relapse (median 267% (range 139-1480%) v 220% (range 138-1236%). CONCLUSION--Monitoring of serum thyroid stimulating antibody was a good guide to the duration of treatment as it allowed the treatment period to be considerably shortened in a large group of patients with no loss of efficiency.