Recurrence of thyrotoxicosis after attack of allergic rhinitis in patients with Graves' disease

Graves' disease is frequently aggravated during antithyroid drug therapy; however, little is known of its aggravating factors. We studied 83 patients with Graves' disease who were euthyroid for at least 6 months under antithyroid maintenance therapy, and we examined the relationship between thyrotoxicosis relapse, attack of allergic rhinitis, and peripheral eosinophil increase. Forty-one patients showed thyrotoxicosis relapse; of these, 22 (54%) showed peripheral eosinophil increase, and 14 (34%) had attacks of allergic rhinitis. In the remaining 42 patients without thyrotoxicosis relapse, only 4 (10%, P < 0.001) showed an increase in peripheral eosinophils, and only 3 (7%, P < 0.01) had allergic rhinitis. Recurrence of thyrotoxicosis was observed with the increase in serum levels of TSH-receptor antibodies and increase in eosinophils 2 months after the attack of allergic rhinitis. Three patients with seasonal allergic rhinitis showed thyrotoxicosis relapse at the same time of year within 2 consecutive years. Our findings indicate that allergic rhinitis can be an aggravating factor of Graves' disease and suggest that the preceding increase in peripheral eosinophils can be a predictive indicator of recurrence of thyrotoxicosis during antithyroid drug therapy.     

Sexual behavior in married women with chronic gynecologic inflammation]

In patients with the first manifestation of hyperthyroidism of Graves' disease, antithyroid drug treatment is the therapy of first choice. Treatment has to be carried out depending on iodine supply of the individual patient with the lowest possible drug dose. Controls of treatment have to be done in short intervals (every 2 weeks) until euthyroidism is reached, afterwards controls of thyroid function have to be done every three months. After euthyroidism is established, the combination of antithyroid drug therapy with thyroid hormones may be useful to avoid hypothyroidism or goiter development during treatment in contrast to a monotherapy with antithyroid drugs. Antithyroid drug treatment has to be carried out for one year. The remission rate of patients does not increase with higher doses of antithyroid drugs or a longer treatment duration. The determination of TSH receptor antibodies does not help predicting a relapse of hyperthyroidism of Graves' disease in the individual patient at the end of treatment. Regular follow-up controls after antithyroid drug treatment are necessary to recognize relapse of Graves' disease in time.     

Outcome of Graves' disease after antithyroid drug treatment in Taiwan

The outcome of Graves' disease after treatment with antithyroid drugs (ATDs) varies widely among countries, and large-scale studies in Asia are rare. We investigated the associations of various clinical and laboratory features with the outcome of ATD therapy for Graves' disease in Taiwan. A total of 210 patients (177 women, 33 men; mean +/- SD age, 41.7 +/- 15.1 yr) treated with ATD in Taiwan were included. ATD therapy started with methimazole 30 mg daily or propylthiouracil 300 mg daily and was continued until a euthyroid state was achieved. Afterwards, 154 patients received a maintenance dose of ATD alone, while 56 patients received a combination of an ATD and thyroxine (L-T4). Patients were considered to be in remission if they remained in a euthyroid state for more than 2 years after drug withdrawal. The mean follow-up periods were 45.0 +/- 20.9 months for patients with remission and 30.4 +/- 19.8 months for those with relapse. Relapse occurred in 126 (60%) patients during the follow-up period, within 3 months after drug withdrawal in 47 (37%), and within 6 months in 60 (46%). The relapse rate was 100% among patients with two or more previous relapses. Patients with a second occurrence had a higher relapse rate than those with a first occurrence (84% vs 43%). Past history of recurrence, goiter size, thyroid-stimulating hormone level and thyrotropin-binding inhibition immunoglobulin activity at the end of ATD treatment were independently associated with relapse. Prolonged duration of treatment did not yield better results in patients with larger goiters or a history of recurrence, or both. Combination therapy with L-T4 yielded similar results to those achieved with ATD treatment alone. In conclusion, the relapse rate of Graves' disease after ATD treatment in Taiwanese patients was high, especially in those with a history of recurrence. The treatment duration and drug regimen did not affect the outcome.     

Malaria in the southern sanitary district of Dakar (Senegal). 2. Entomologic data]

This study aimed to investigate the cause of persistently increased serum gastrin concentration seen in some Graves' disease patients even when euthyroid during antithyroid drug treatment. The subjects studied consisted of three groups: 33 patients with a common-type of Graves' disease, 14 with triiodothyronine (T3)-predominant Graves' disease (characterized from previous studies as having potent immunologic abnormalities including greater concentrations of thyroid-stimulating antibodies together with larger goiter size), and a group of 20 normal subjects. Fasting serum gastrin concentrations in common Graves' disease patients were significantly higher than those of normal subjects (58.4 +/- 38.9 pmol/L vs. 37.8 +/- 18.9 pmol/L [mean +/- SD], p < 0.05). The serum gastrin concentrations were even greater in T3-predominant Graves' disease patients than common Graves' disease patients (162.9 +/- 224.0 pmol/L vs. 58.4 +/- 38.9 pmol/L, p < .05). Serum pepsinogen I (PGI) concentrations were significantly lower in the T3-predominant patient group than the common Graves' group (24.0 +/- 12.9 ng/mL vs. 39.7 +/- 19.6 ng/mL, p < .05). Serum ratios of PG I to PG II were significantly lower in the T3-predominant Graves' disease patients than normal subjects (3.59 +/- 2.66 vs. 5.97 +/- 1.56, p < .01). The ratios also had a significant (p < .05) inverse correlation with serum gastrin concentrations in T3-predominant Graves' disease patients. The results suggest that autoimmune gastritis is associated with Graves' disease, particularly in patients with potent thyroid-autoimmunity.     

Management and outcome of borderline ovarian tumors incidentally discovered at or after laparoscopy

OBJECTIVE: The optimal antithyroid drug regimen for Graves' disease remains a matter of controversy. The European Multicentre Trial Group has investigated the effects of methimazole drug dose on the long-term outcome of Graves' disease. DESIGN: Extended follow-up of patients from a prospective multicentre trial, designed to study methimazole dose effects on the outcome of Graves' disease. We have reported previously that the relapse rates did not differ after a medication-free observation period of 12 months; the relapse rates were 37% and 38%, respectively. In this paper, we describe the outcome in these patients after a mean observation period of 4.3 +/- 1.3 years and have looked for potential predictors of this outcome. PATIENTS: Three hundred and thirteen patients with Graves' disease were randomized to treatment with a constant dose of 10 or 40 mg of methimazole for 1 year, with levothyroxine supplementation as required. MEASUREMENTS: At the time of inclusion into the trial: thyroid size, T4, T3, TSH-binding inhibiting immunoglobulins, urinary iodide excretion, thyroid uptake, Crook's therapeutic index of hyperthyroidism (a measure of clinical disease severity). At the time of follow-up examination: TSH, T4, T3, thyroid size, thyroid ultrasound, THS-binding inhibiting immunoglobulins. RESULTS: The overall relapse rate was 58%. There was no difference in relapse rates between patients treated with either 10 or 40 mg of methimazole (58.3 vs. 57.8%). Five patients had become spontaneously hypothyroid, without obvious relationship to antithyroid drug dose. Patients who relapsed and patients who remained in remission did not differ with respect to: age, goitre size, ophthalmopathy, median iodine excretion, serum T4 or serum T3, Crook's therapeutic index and thyroid uptake at the time of study entry. Thus, none of these variables was potentially suitable for predicting outcome. This finding was confirmed by Cox's proportional hazard regression. Thyroid volume, measured by ultrasound, did not differ between patients in remission and patients with relapse. There was no difference in the course of endocrine eye signs, in the requirement for steroid and radiotherapy for eye signs, or in thyroid echostructure between patients in the 10 and in the 40 mg group, nor was serum TSH different in patients who had remained in remission (0.8 +/- 0.6 mU/l in the 10 mg group, 1.0 +/- 0.8 mU/l in the 40 mg group). CONCLUSIONS: The dose of methimazole in Graves' disease therapy can safely be kept to the minimal required dose. This will provide the same chance of remission as higher doses, and provide the best balance of risk and benefit.     

Dual-electrode detection for capillary electrophoresis/electrochemistry

OBJECTIVE: The aims of the study were to establish the usefulness of color Doppler sonography in assessing changes in thyroid blood flow during the course of Graves' disease and to investigate which of several variables (thyroid volume, number of intraparenchymal vessels, and blood flow in the thyroid artery) were best related to thyroid hyperfunction and therefore could be used to evaluate the course of the disease. SUBJECTS AND METHODS: Fifty-six patients with Graves' disease were selected and divided on the basis of clinical and laboratory data into four groups: patients untreated at first diagnosis, patients undergoing antithyroid drug treatment, patients in remission after withdrawal of therapy, and patients having a relapse of hyperthyroidism. Ten healthy subjects served as controls. RESULTS: Patients with active hyperthyroidism (at first diagnosis, during treatment, or at relapse) had a significantly enlarged thyroid (p = .005); intrathyroid vascularization, evaluated as number of vessels per square centimeter (p < .0001); and blood flow in the thyroid artery (p < .0001) compared with control subjects and with patients in remission after withdrawal of therapy. During treatment, sonographic values were slightly lower but not significantly different from those registered in patients at the onset of hyperthyroidism, indicating that normalization of vascularity does not parallel the drug-induced decrease of hormonal synthesis. Among 21 patients in remission, the nine patients who had a relapse shortly after the examination had a higher number of vessels per square centimeter (2.18 +/- 0.34 versus 1.03 +/- 0.16, p = .03) and higher flow in the thyroid artery (80.3 +/- 19.1 versus 10.6 +/- 2.3 ml/min, p = .01) than did the other 12 patients who remained in stable remission, despite normal hormonal levels in both groups. CONCLUSION: Our results suggest that color Doppler sonography can be used to assess activity of Graves' disease and to predict the outcome of the disease after withdrawal of medical therapy.     

TSH suppression combined with carbimazole for Graves' disease: effect on remission and relapse rates

OBJECTIVE: We studied the influence of TSH suppressive therapy combined with carbimazole (CBZ) on treatment outcome in Graves' disease. DESIGN: Open non-randomized prospective study. SETTING: University Hospital of Montpellier, France. SUBJECTS: Sixty-six consecutive patients without prior treatment were included. All the patients were treated initially with 30 mg of CBZ. After 1 month of treatment, one group continued CBZ alone (n = 23), another group received a combination of CBZ plus T3 (n = 19) and a third group received CBZ and 3,5,3'-triiodothyroacetic acid (Triac, n = 24). Therapy was stopped when remission was obtained based on clinical euthyroidism, normalization of FT4 and of early radioiodine uptake. Nine patients with medical treatment failure or major side effects requiring to stop antithyroid drugs underwent surgery or radioiodine therapy. Nine patients were lost to follow-up. The remaining 48 patients were available for analysis of both remission and relapse. RESULTS: The median duration of therapy was 18 months (range, 4-41 months). Based on clinical examination, goitre size at 4 months decreased more in the CBZ + T3 and CBZ + Triac groups than in the CBZ group (P = 0.02). The overall remission rate tended to be higher in the groups treated with CBZ + T3 and CBZ + Triac than in the group treated with CBZ alone, but the difference did not reach statistical significance (P = 0.17). No difference in the relapse rate was observed between the three groups. CONCLUSION: TSH suppression combined with CBZ has little or no effect on remission and relapse rates in Graves' disease patients.     

Thyroid vascularization by color doppler ultrasonography in Graves' disease. Changes related to different phases and to the long-term outcome of the disease

To investigate possible correlations between thyroid vascularization and activity of Graves' disease, we measured blood flow (TBF) at the inferior thyroid artery and intraparenchymal vascularization (number of vessels per square centimeter) by color Doppler ultrasonography (CDU) on Graves' patients at different phases of the disease. We studied 88 patients cross sectionally: 22 untreated; 17 euthyroid after 6 months of methimazole; 49 euthyroid at drug withdrawal after 12 to 24 months of treatment. The patients of the latter group were followed up for 29.1 +/- 6.3 months after discontinuation of treatment. On the day of CDU examination, free triiodothyronine (FT3), free thyroxine (FT4), thyrotropin (TSH), antiperoxidase and anti-TSH receptor (TRAb) antibodies were measured. Vascularization indices were significantly higher in the Graves' patients than in controls. In the patients euthyroid under treatment, vascularization was not significantly lower than in the untreated group, but TBF and vessel number both appeared clearly reduced in the patients tested at drug withdrawal. The vascularization indices at drug withdrawal were significantly higher in the patients who relapsed than in those in stable remission: TBF (mL/min) 50.6 +/- 36.8 vs. 23.8 +/- 17.5, p = 0.001; vessel number/cm2 1.8 +/- 0.8 vs. 0.8 +/- 0.5, p = 0.002. A multivariate analysis, evaluating the predictive value of vascularization, hormonal and immunological parameters for relapse, demonstrated a significant predictive value for TRAb (RR 8.2; p = 0.001) and a weak predictive value for TBF (RR 1.1; p = 0.02). In conclusion, CDU examination confirms that thyroid hypervascularization in Graves' disease is not related to thyroid hormone circulating levels. The association of increased TBF and high levels of TRAb in the relapsing forms of disease suggests that thyroid hypervascularization is probably related to the activity of the underlying autoimmune processes.     

Hyperthyroidism: diagnosis and management of Graves' disease

Hyperthyroidism, or thyrotoxicosis, results when the body's tissues are exposed to excessive levels of thyroid hormone. Hyperthyroidism affects 2% of women but only one-tenth as many men. Graves' disease is the most common form of hyperthyroidism, often occurring in young adults. It is an autoimmune disorder with an important genetic component. Hyperthyroidism's hallmarks include goiter and myriad signs and symptoms related to increased metabolic activity in virtually all body tissues. Increased sensitivity to circulating catecholamines adds to the clinical picture. Diagnosed by patient history, physical examination, and laboratory tests, Graves' disease is treated with antithyroid drugs, radioactive iodine, and/or surgery, plus supportive therapy. A good treatment outcome can be expected; long-term follow-up is indicated.     

High dosage thyroxine treatment in therapy and prevention refractory patients with affective psychoses

Natural killer (NK) cell activity of peripheral blood lymphocytes (PBL) against k562 human tumor cell targets was studied in patients with Graves' disease and Hashimoto's thyroiditis. NK activity was measured in a standard 4-hour 51chromium (Cr) release assay. Cytotoxicity was expressed as lytic units (LU)/10(6) PBL. Significantly decreased NK cell activity was demonstrated in both groups of patients, with mean (+/- SE) lytic units of 10.3 (+/- 9.1) and 13.3 (+/- 10.3) for patients with Graves' disease and Hashimoto's thyroiditis, respectively, compared with 36.0 (+/- 26.3) for age- and sex-matched normal subjects. When patients with Graves' disease were analyzed according to their thyroid status; NK activity was significantly depressed in (1) hyperthyroid patients before treatment; (2) hyperthyroid patients receiving antithyroid therapy; and (3) euthyroid patients receiving antithyroid therapy, compared with normal subjects. Graves' disease patients who were hypothyroid after radioactive iodine therapy or thyroidectomy had normal NK activity. No significant differences between hyperthyroid and euthyroid patients or between hypothyroid patients and normal subjects were demonstrated. NK activity in patients with Graves' disease did not correlate with serum levels of thyroxine, the presence or severity of ophthalmopathy, or titers of serum thyroid antibodies. In patients with Hashimoto's thyroiditis there was no correlation between NK activity and goiter size, titers of antithyroid antibodies, or thyroid status. These findings suggest that depression of NK activity in both disorders is secondary to abnormalities of thyroid hormone secretion, although an effect of the underlying autoimmune reactions has not been excluded.     

Improved and effective assays of the glutamic oxaloacetic transaminase by the coenzyme-apoenzyme system (CAS) principle

257 patients have been reviewed 1-5 years (mean 3 years 2 months) after receiving one of five dose regimes of 125I for thyrotoxicosis. The cumulative incidence of hypothyroidism was 34% and of persistent thyrotoxicosis 17%. The group receiving doses between 351 and 500 muCi/g had the highest proportion of euthyroid patients (65%) with the lowest requirement for repeat therapy (46%). In the euthyroid patients, increasing dose of 125I was associated with progressive decline in mean thyroxine (T4) level and free thyroxine index (FTI) within the respective normal ranges, and increase in mean thyroid stimulating hormone (TSH) level to above the normal range. Euthyroid patients with elevated TSH levels had significantly lower T4 and FTI values compared with those with normal TSH, and showed a 3-4-fold increased rate of development of hypothyroidism over 1 year. Euthyroid patients with elevated T3 levels remained euthyroid during the subsequent year and mean T3 levels declined significantly, suggesting that abnormally elevated T3 levels after 125I do not generally indicate impending relapse of thyrotoxicosis. It is concluded that the potential admantages of 125I therapy for thyrotoxicosis in reducing the incidence of hypothyroidism have not been realized in practice.     

Haemorrhagic syndrome after massive transfusion of blood for traumatic liver rupture: disseminated intravascular coagulation? (Author''s transl)

The rate of control of thyrotoxicosis during the first 2 weeks of treatment was documented in 63 patients. Twenty-three patients received carbimazole 40 mg plus lithium carbonate 750 mg daily and a comparable group of 20 patients were given carbimazole 40 mg plus potassium iodide 120 mg daily. In the lithium treated patients the mean percentage fall of serum T4 after 2 weeks treatment was 49% and the fall in serum T3 57%. The results were similar in the iodide treated patients; the mean falls in serum T4 and T3 being 47% and 64%, respectively. Serum lithium values varied between 0.1-1.25 mEq./l; lithium side effects were minor. In a companion study 20 patients were treated with carbimazole alone. The responses in this group were less impressive; the mean falls in serum T4 and T3 at 2 weeks being 18% and 36%, respectively. It is concluded that lithium is a safe adjunct to conventional antithyroid drug therapy in the initial treatment of acute thyrotoxicosis.     

Amiodarone-induced thyrotoxicosis: is there a place for surgery?

Amiodarone-induced hyperthyroidism has on most instances been reported as mild, and thyroid functions return to normal after discontinuation of the drug. Nevertheless, life-threatening amiodarone-induced thyrotoxicosis has also been described. Conventional treatments such as antithyroid drugs (thionamide) and corticosteroids are essentially ineffective or fail to alter the dramatic course of the thyroid crisis. This limited effectiveness of medical therapy, particularly in patients with previously neglected or unknown thyroid disease, prompted us to intervene surgically. We report a series of nine patients who underwent total or near-total thyroidectomy as a first-line therapy for five of them. Surgery resulted in rapid resolution of thyrotoxicosis with an uneventful postoperative course. This approach has the advantage of immediate effectivity, low risk of relapse, and appears to be the only treatment that permits continued therapy with amiodarone when the drug appears needed to control a life-threatening arrhythmia.     

Medical therapy of Graves' disease: does thyroxine prevent recurrence of hyperthyroidism?

Sixty patients with Graves' disease (GD) hyperthyroidism were distributed in two randomized groups. Patients in group A (n = 30) received carbimazole by a titration regimen, and patients in group B (n = 30) were treated with higher doses of carbimazole plus T4. Clinical and analytical evaluations were done at baseline, during treatment (18.4 +/- 2.6 months), and after, until the relapse of hyperthyroidism, or for 4.98 +/- 1.6 yr in patients who did not relapse. There were no differences in clinical parameters, thyroid hormones, or TSH binding inhibitory immunoglobulins (TBII) levels between the two groups, either at baseline or at the end of treatment. Serum TSH persisted undetectable in 16 out of 60 patients (group A: 9; group B: 7), after treatment. Relapse occurred in 38 patients (63.3%), (group A: 18 (60%) vs. group B: 20 (66.7%)). Patients who relapsed had bigger goiters at baseline (P = 0.02) and at the end of treatment (P = 0.03). Eighty-seven percent (14/16) of patients with undetectable TSH after therapy relapsed, vs. 54.5% (24/44) of those with normal TSH (P = 0.01). Undetectable TSH at the end of treatment was the only independent variable in the logistic analysis to predict relapse. Treatment modality did not influence the relapse rate. This study has found that, in Spanish patients, the use of high doses of carbimazole with T4 offers no advantages in the treatment of GD hyperthyroidism.     

Postpartum thyroiditis and Basedow disease

BACKGROUND: The postpartum period is characterized by a rebound in autoimmunity secondary to immune tolerance induced by pregnancy, creating favorable conditions for flare up of Graves' disease or autoimmune thyroiditis. Postpartum thyroiditis is a recognized clinical entity. CASE REPORT: Six years after onset of Graves' disease treated with antithyroid drugs, a 25-year-old woman had a high serum level of antithyroperoxidase antibodies a few months before she became pregnant. Six weeks after delivery, she developed signs of hyperthyroidism and goiter. The diagnosis of postpartum thyroiditis was retained. Her condition regressed spontaneously to euthyroidism then hypothyroidism. DISCUSSION: The therapeutic options involved underline the importance of distinguishing between Graves' disease and postpartum thyroiditis. The diagnosis of postpartum thyroiditis is based on history taking, clinical findings, and laboratory tests, especially isotope uptake.     

Radioiodine treatment of Graves' disease in young people

In Europe young patients with Graves' disease are usually treated with antithyroid drugs initially, then if hyperthyroidism recurs after a prolonged course of such medication, they are offered definitive treatment by subtotal or total thyroidectomy. Neither of these forms of treatment is free from problems. Impressed with the simplicity and safety record of radioiodine therapy, we have treated 8 young patients with radioiodine. The patients all presented with typical Graves' disease and relapsed after 18-24 months of treatment with antithyroid drugs. They were then given the option of a further course of antithyroid medication or definitive treatment with radioiodine or surgery. Those who opted for radioiodine were treated with 131iodine in a dose of 300 MBq with the intention of ablating the thyroid. Antithyroid medication was resumed for 4-6 months and then withdrawn. Four patients became hypothyroid after a single dose of radioiodine but 4 needed a second dose. All became hypothyroid within 2 years. No adverse effects were observed, in particular no patient showed any deterioration in their eye disease. Radioiodine offers a simple, effective and inexpensive method of treatment for Graves' disease in young patients. There are no immediate adverse effects and, although some theoretical concerns remain, to date the long-term safety record of thyroid ablation is excellent and the potential risks seem to us to be outweighed by the advantages. Even when a moderately high initial dose of radioiodine is used, a second dose may be needed.     

Diagnosis and treatment of thyrotoxicosis in childhood. A European questionnaire study

A covering letter and a questionnaire covering the diagnosis and treatment of thyrotoxicosis in childhood was circulated between October 1992 and February 1993 amongst 672 European members of the European Thyroid Association (ETA) and members of the European Society for Pediatric Endocrinology (ESPE). Almost 50% replied to the letter and 99 individuals or groups from 22 countries completed the questionnaire. A consensus was reached on the use of total thyroxine (T4) and/or free T4 and thyrotropin as routine diagnostic tools. Two-thirds included total triiodothyronine (T3) and/or free T3 and 32% used a thyrotropin-releasing hormone test. Surprisingly, thyroglobulin autoantibodies were used as a routine test by 78%; 63% included thyrotropin receptor antibodies and 60% microsomal antibodies, whereas only 50% measured thyroperoxidase antibodies. For thyroid imaging, 40% performed a thyroid scintigram and 56% measured the size of the thyroid gland by ultrasound. Antithyroid drugs (ATD) were the basic initial treatment of choice given by 99% of the respondents for children with uncomplicated Graves' disease. Carbimazole, methimazole and thiamazole were the most frequently used drugs, with a median initial dose of 0.8 mg.kg-1.day-1. Two-thirds added beta-blockers and a few used sedatives. The ATD dose was adjusted for each patient by 39%, whereas 56% combined ATD with T4 for long-term treatment; 84% gave treatment for a fixed period (44% for 1-2 years). Surgery was considered the treatment of choice in children with an adenoma (83%), with a nodular (53%) or large goiter (16%) and recurrence after ATD (14%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Plasma renin and aldosterone in thyroid diseases

The effect of thyroid hormones on the renin-angiotensin-aldosterone system has not been fully resolved. Highly specific immunoassays for measurement of renin, aldosterone, free T4 (fT4), free T3 (fT3) and ultrasensitive TSH enables a direct and more accurate measurement of these hormones. We investigated the relationship between plasma renin, aldosterone and thyroid hormones in the basal state and after intravenous frusemide. This is a cross-sectional study involving 37 patients with thyrotoxicosis, 42 rendered euthyroid with normal fT4, fT3 and TSH levels, 17 with euthyroid levels of fT4 and fT3 but suppressed TSH, and 11 with hypothyroidism. Basal plasma renin was significantly higher in thyrotoxicosis (63.4 +/- 9.8 microU/ml, mean +/- SEM) compared to euthyroid (32.7 +/- 4.4 microU/ml) and hypothyroid (26.7 +/- 9.8 microU/ml). Basal plasma renin for euthyroid with suppressed TSH (41.0 +/- 7.4 microU/ml) was significantly higher than hypothyroid (p = 0.02). Basal plasma aldosterones were not significantly different except for suppressed TSH (157.7 +/- 13 pg/ml), which was higher than normal (109.9 +/- 10.4 pg/ml; p = 0.04). Following frusemide, plasma renin and aldosterone were significantly increased in all groups. Plasma renin was highly correlated to fT3 (r = 0.405, p < 0.001), total T3 (r = 0.359, p < 0.001), fT4 (r = 0.331, p < 0.001) and TSH (r = 0.300, p < 0.001) in the basal state, but less to total T4 (r = 0.248, p < 0.01). Plasma renin correlated poorly to serum aldosterone (r = 0.212, p < 0.03). This study clearly showed that regulation of renin was mainly influenced by fT3, and that aldosterone response to frusemide was blunted in thyrotoxicosis despite normal electrolytes.     

Thyroid hormones modulate serum leptin levels: observations in thyrotoxic and hypothyroid women

Thyroid hormones and leptin are both involved in the regulation of energy metabolism. Serum leptin concentrations were measured in women with thyrotoxicosis (n = 21, mean age 45 years) or hypothyroidism (n = 14, mean age 44 years) before and 3 months after restoration of the euthyroid state. Serum leptin concentration tended to increase in both hypothyroid (14.7+/-3.5 vs 17.8+/-3.9 ng/ml, p = 0.06) and thyrotoxic (11.9+/-1.7 vs 14.4+/-2.0, p = 0.08) women after treatment (values given as mean +/- SE in the untreated and the euthyroid state respectively). Body mass index (BMI) was lower in thyrotoxic women than in hypothyroid women in the untreated state (22.1+/-0.7 vs. 26.2+/-1.9, p < 0.05). BMI was not different between both groups after treatment (24.5+/-0.7 vs. 26.3+/-2.1, p = 0.37), due to an increase of BMI in the thyrotoxic women; BMI did not change in the hypothyroid group. After controlling for BMI in a multivariate regression analysis, serum leptin concentrations were lower in hypothyroid women than in thyrotoxic women (p < 0.05), whereas posttreatment values of leptin did not differ (p = 0.44). When leptin concentrations were expressed as standard deviation scores (Z-scores) from the mean value of female controls matched for BMI and age as reported earlier, Z-scores were lower in the hypothyroid than in the thyrotoxic women (-0.63+/-0.21 vs. 0.53+/-0.18, p = 0.001). After treatment, Z-scores did not deviate from the expected values (0.05+/-0.28 vs. 0.08+/-0.16, p = 0.98). Z-scores differed before and after treatment in both hypothyroid (p = 0.01) and thyrotoxic (p = 0.02) patients. In conclusion, these data obtained in thyrotoxic and hypothyroid women indicate that thyroid states modulates serum leptin concentrations independent of BMI, with a small decrease in hypothyroidism and a small increase in thyrotoxicosis.