24-hour Uptake Research Articles

Inhibited Hypothalamic-Pituitary-Thyroid Axis in Type I Pseudohypoparathyroidism

To assess the hypothalamic-pituitary-thyroid axis in two patients with the diagnosis of type I pseudohypoparathyroidism established previously by characteristic clinical features and laboratory findings, including low serum Ca++, high parathyroid hormone concentration, and subnormal urinary cyclic adenosine monophosphate (cAMP) responses to exogenous administration of parathyroid hormone. We determined serum thyroxine, triiodothyronine (T(3)), T(3) resin uptake, and 24-hour thyroidal uptake of 123 I before and after subcutaneous administration of thyroid-stimulating hormone (TSH), 10 U daily for 3 days. Serum TSH levels were determined before and again at 15, 30, 45, and 60 minutes after intravenous administration of thyrotropin-releasing hormone (TRH) (400 microg) after an overnight fast. Values noted in the two patients with type I pseudohypoparathyroidism were compared with those obtained in 10 normal volunteer control subjects. Serum thyroxine (T(4)), triiodothyronine (T(3)), T(3) resin uptake, and 24-hour 123 I uptake values for both patients with type I pseudohypoparathyroidism were within the normal ranges (5.5 to 11.5 microg/dL for T(4), 90 to 190 ng/dL for T(3), 35 to 45% for T(3) resin uptake, and 10 to 35% for 24-hour 123I uptake). Their responses to administration of TSH, however, were all significantly lower in comparison with the mean values for the 10 healthy control subjects. Basal TSH was higher in both patients with type I pseudohypoparathyroidism than in normal subjects, but TSH responses after administration of TRH, although not significantly different from normal, were blunted in relationship to the basal concentrations, as expressed as a percentage increase in TSH as well as a cumulative TSH response. The responses of pituitary thyrotrophs to TRH and the thyroid gland to TSH were both considerably inhibited in the patients with type I pseudohypoparathyroidism in comparison with normal control subjects. This finding may be yet another evidence of the lack of adequate generation of cAMP, an important second messenger needed for normal functioning of most polypeptide hormones, including TRH and TSH, in this syndrome.

The development of transient hypothyroidism after iodine-131 treatment in hyperthyroid patients with Graves' disease: prevalence, mechanism and prognosis.

Recovery of thyroid function in patients following hypothyroidism induced by 131I therapy for Graves' disease has been described, but only a few detailed clinical and biochemical studies of this phenomenon (transient hypothyroidism) have been published. The prevalence, mechanism, and final outcome of transient hypothyroidism in 260 patients with Graves' disease treated with 131I was studied. A retrospective study. Two hundred sixty patients with Graves' disease, treated with 131I between 1 and 15 years previously, were categorized into 4 groups according to their thyroid function during and 1 year after therapy (Group 1: permanent hypothyroidism, 28 patients; Group 2: transient hypothyroidism, 39 patients; Group 3: euthyroidism without transient hypothyroidism, 83 patients; Group 4: hyperthyroidism, 110 patients). We compared total T4, total T3, TSH, anti-thyroglobulin (TGHA) and anti-microsomal (MCHA) antibodies, the TSH-binding inhibitory immunoglobulin (TBII) index, thyroid weight, dose of 131I, and 24-hour 131I uptake as pretreatment variables. The mean time for permanent hypothyroidism to develop was estimated by the Kaplan-Meier product limit method. The TBII index and thyroid stimulating antibody (TSAb) activity were measured in seven patients from Group 1 and in nine patients from Group 2 at the time that they became hypothyroid. Hypothyroidism developing within 12 months of therapy was transient in 58% (39/67) of patients. No pretreatment variables were found to differ between patients with and without transient hypothyroidism. The mean estimated time between therapy and the development of permanent hypothyroidism was 96 months in Group 2; this time interval was significantly shorter than 126 months in Group 3 and 129 months in Group 4 (P < 0.05, P < 0.01, respectively). TSAb activity was > 500% In 78% (7/9) of patients from Group 2, which was significantly higher than that found (14%, 1/7) in Group 1. These results indicate that (1) more than half the patients who developed hypothyroidism within 6 months after 131I treatment for Graves' disease recovered spontaneously, (2) TSAb activity might play some role in the recovery of transient hypothyroidism, and (3) the development of transient hypothyroidism may influence long-term thyroid function.

Papillary thyroid cancer in Saudi Arabia. Clinical, pathologic, and management characteristics.

During a 3-year period, 233 patients with papillary thyroid cancer were seen at King Faisal Specialist Hospital (KFSH) (79% were female; 94% were national subjects). Pathology revealed 88% pure papillary carcinoma and 12% mixed papillary and follicular carcinoma, 7% microfocus, 18% well encapsulated, 24% capsular invasion, and 51% soft tissue invasion. Thirty percent of patients who had initial surgery not done at KFSH compared with 93% of patients who had initial surgery done at KFSH had an I-123 24-hour uptake < 5%. One hundred seventeen patients required completion thyroidectomy at KFSH for significant residual thyroid tissue, 56% of those had residual papillary carcinoma. The amenability of papillary thyroid cancer for cure necessitates the optimization of management at the national level. In Saudi Arabia, papillary thyroid cancer presented in an advanced stage, especially in males as manifested by the large primary tumor size, advance pathologic staging, and distant metastases at the time of presentation. Findings at second surgery, showed significant residual disease.

Therapy Dose Calculation in Graves' Disease Using Early I-123 Uptake Measurements

A retrospective study was performed to assess the feasibility of using the 4-hour I-123 early uptake value in the calculation of the treatment dose of radioactive iodine in Graves' disease patients. The Graves' disease patients were randomly divided into two groups. Data from the first group of 35 patients were used to obtain a regression relationship between the early 4-hour uptake (EUp) and 24-hour late uptake values (LUp). This equation, LUp = -38.618 + 65.216 Log (EUp) was used to estimate the predicted late uptake (PUp) from (EUp) in the second group of 34 patients. LUp was used to calculate the I-131 therapy dose for treatment in these patients. In 28 clinically euthyroid patients, the 4-hour uptake I-123 radioactive iodine uptake (RAIU) ranged from 7% to 20% (mean, 12 +/- 3.5%). In 60 Graves' disease patients, the 4-hour RAIU ranged from 15% to 100% (mean, 57 +/- 24.8%). Of these, there were five patients with a normal 4-hour uptake, but elevated 24-hour uptake. LUp correlated well with PUp (r = 0.81162), as did the dose calculation based on predicted and observed 24-hour uptake values (r = 0.82204). Thus, same day measurement of uptake and treatment of Graves' disease is feasible.

A Case of Graves' Disease in which Hypothyroidism First Developed, Followed by Hyperthyroidism, and Finally Hypothyroidism Recurred: A Four-year Follow up

A 63-year-old female with a diffuse goiter was referred for evaluation of her thyroid function. When she visited the hospital in January 1991, her serum levels of free T3 (FT 3), free T4 (FT 4), and TSH were 3.1 pmol/l, 12 pmol/l, and less than 0.10 mU/l, respectively. Her thyroid function was thought to have changed from thyrotoxic to euthyroid or hypothyroid since she had been diagnosed as subclinically hyperthyroid at another clinic in November 1990. Her TSH level later increased to 83.2 mU/l. Treatment with T3 was started in March 1991. The T3 administration was terminated in January 1992, when her FT 4 level had increased to 8 pmol/l. Histological examination revealed the presence of chronic thyroiditis in January 1992. She developed mild hyperthyroidism in February 1992, followed by recurrent hypothyroidism in May 1993. The 24-hour thyroidal radioactive iodine uptake (RAIU) was 32.1% in March 1992. Treatment with T3 was restarted in June 1993. T3 therapy was replaced with T4 therapy in August 1994 since her FT 4 level remained low up to July 1994. Ultrasonography of the thyroid revealed diffuse low echogenicity in the hypothyroid state (January 1991 and March 1994). On the other hand, an ultrasonogram obtained during the mild hyperthyroid state (January 1993) showed echo levels increased in the anterior half of the thyroid. C-reactive protein (CRP) was positive at the first visit, in May 1993 when hypothyroidism recurred and in February and March 1994 when her thyroid function deteriorated. However, she did not complain of neck pain during the course of her illness. The results of TSH-binding inhibitor immunoglobulins (TBII) and thyroid-stimulating antibodies (TSAb) were strongly positive at her first visit. Their activities remained high through the end of 1991 and then gradually decreased, indicating that she had Graves' disease. Thyroid-stimulation-blocking antibodies (TSBAb) were not detected throughout the investigation period. The present findings indicate that her thyroid function changed depending on the balance between TSAb activities and the destructive changes in the thyroid. Inflammation might have played a role in the destruction of the thyroid.

Enhanced Erythropoietin Response to Acute Hypoxemia in Mice with Pharmacological Depression of Erythropoiesis.

The recent report of a depression of stimulated production of erythropoietin (EPO) in mice with enhanced erythropoiesis suggests that unknown mechanism (s) other than hypoxia may be involved in the regulation of EPO formation. The present study was thus designed to investigate EPO production during acute hypoxemia in a mouse model in which the oxygen-carrying capacity of blood, the plasma EPO level, and the plasma EPO half-life were within normal values in spite of a marked depression of the red cell production rate (RCPR) induced by cyclophosphamide (CP) administration. Injection of 100 mg/Kg of the drug into adult female CF-1 mice that previously received 0.4 ml of packed red cells depressed markedly the 24-hour RBC 59Fe uptake without affecting the plasma immunoreactive EPO level and the plasma disappearance of 1251-labeled recombinant human EPO. The EPO production rate, calculated from the change in plasma EPO levels and the estimated EPO clearance rate, after 4 h of exposure to hypobaric air was about 2.8 times higher in mice with CP-induced inhibition of the RCPR than in mice with normal RCPR. The results support the hypothesis that the EPO production rate in mammals is not only related to the oxygen supply to the tissues relative to their oxygen needs (main stimulus) but also to the erythroid activity of the marrow (modulatory action).

Is calculation of the dose in radioiodine therapy of hyperthyroidism worth while?

The persistent controversy as to the best approach to radioiodine dose selection in the treatment of hyperthyroidism led us to perform a study in order to compare a fixed dose regime comprising doses of 185 370 or 555 MBq based on gland size assessment by palpation only, with a calculated 131I dose based on type of thyroid gland (diffuse, multinodular, solitary adenoma), an accurate thyroid volume measurement, and a 24-hour 131I uptake determination. Prospective randomized study. Two hundred and twenty-one consecutive hyperthyroid patients referred for 131I treatment. Four Patients who died for reasons unrelated to hyperthyroidism, 7 lost to follow-up and 47 who did not receive antithyroid drugs after treatment, were excluded. The remaining 163 patients (143 women) were studied, divided into subgroups according to the type of gland. They all received antithyroid drugs prior to 131I treatment and this was resumed 7 days after treatment for a period of 3 weeks. Thyroid function variables were determined approximately 2 weeks before 131I treatment, and again 1, 2, 3, 6, 9 and 12 months after treatment. Prior to 131I therapy the size of the thyroid gland was determined by ultrasound and a 24-hour uptake of 131I was carried out. Thyroid volume was also estimated 12 months after 131I therapy in 78 of the 163 patients. Twelve months after the initial 131I dose patients could be classified as euthyroid, hyperthyroid or hypothyroid. Neither in the group of 163 patients nor within the three subgroups of hyperthyroidism could any significant difference in outcome between the two treatment regimes be demonstrated. Thirty-two of 78 patients (41%) in the calculated dose group and 30 of 85 patients (35%, NS) in the fixed group were classified as hyperthyroid. Seven of 78 (9%) in the calculated dose group and 6 out of 85 (7%, NS) in the fixed dose group were classified as permanently hypothyroid. Finally, 39 of 78 (50%) in the calculated dose group and 49 of 85 (58%, NS) in the fixed group were euthyroid at 12 months after 131I treatment. One year after 131I therapy thyroid volume was reduced from 59.3 +/- 9.2 (mean +/- SEM) to 36.2 +/- 6.6 ml (average reduction 39%) in the calculated dose group (P < 0.001). This reduction did not differ significantly from the fixed dose group where thyroid volume declined from 61.6 +/- 6.1 to 41.17 +/- 4.7 ml (average reduction 32%) (P < 0.001). A semiquantitative approach is probably as good as the more elaborately calculated radioiodine dose for treatment of hyperthyroidism. It is clearly more cost effective and allows the use of predetermined standard doses.

Evaluation of Early (5 to 6 Hours) Iodine 123 Uptake for Diagnosis and Treatment Planning in Graves' Disease

Twenty-four-hour radioactive iodine uptake measurements necessitate extra visits and time delays in diagnostic confirmation of and therapy planning for hyperthyroid patients. We evaluated the early (5 to 6 hours) measurement of iodine 123 uptake (EU) to predict late (24 hours) uptake (LU) and assessed its value in the management of hyperthyroidism. We conducted a prospective study in 51 previously untreated hyperthyroid and 27 euthyroid patients (initial evaluation group). Patients underwent both 6- and 24-hour 123I uptake measurements. A subsequent 21 patients with Graves' disease (confirmation group) were evaluated in light of regression data generated in the initial evaluation group. An EU value of greater than 20% had a sensitivity of 100%, a specificity of 96%, and a positive predictive value of 98% for the diagnosis of hyperthyroidism and was superior to the most predictive LU value (> 30%), which had a sensitivity of 98%, a specificity of 89%, and a positive predictive value of 94%, in distinguishing the hyperthyroid patients from euthyroid patients or those with subacute thyroiditis. Regression analysis revealed that the 24-hour uptake of the hyperthyroid patients could be predicted from the early measurement with the following formula: LU = 28.94 + 0.584 (EU). The measured EU of the confirmation group was used to calculate a predicted LU with use of this formula. Measured LU and predicted LU correlated well (r = .85, P < .001). Iodine 131 dose calculations were performed post hoc; LU calculated doses correlated with predicted LU doses (r = .91, P < .001). Mean dose differences were small. The EU of 123I can replace 24-hour uptake measurements. Early uptake measurement is reliable and clinically useful for diagnosis confirmation and treatment planning in thyrotoxic patients.

Physical Activity and its Relationship to Cardiovascular Risk Factors in Rural Japanese Men

Methods of quantifying physical activity in a population-based sample are needed to examine the relation of physical activity to cardiovascular diseases. We examined validity and reproducibility of an interviewer-administered physical activity questionnaire for men aged 40-59 years in a rural Japanese population. Validity was tested by comparing the estimate of physical activity from a 24-hour diary and maximum oxygen uptake from ergometer exercise test for forty-five men. There was no difference in the estimates of energy expenditure between the questionnaire and the 24-hour diary in each job classfication. Significant correlations were obtained between total activity estimated by the questionnaire and the 24-hour diary (r=0.66) and between the total activity and maximum oxygen uptake (r=0.30). Correlation coefficients between the test and retest at 1-2 year interval for 83 men were 0.67 for total activity, 0.62 for activity at work, 0.59 for leisure time activity and 0.24 for other activity. Using this questionnaire, energy expenditure in total physical activity was measured in 539 men aged 40-59 years living in a rural community of Akita, northeast Japan. Greater physical activity was associated with higher serum HDL-cholesterol levels, lower relative weight index. There was no significant association of physical activity with blood pressure levels, serum total cholesterol, cigarette smoking, and alcohol intake. Thus, greater physical activity was not always associated with lower coronary risk factors except for HDL-cholesterol. Prospective studies will be needed to clarify the relation of physical activity with cardiovascular disease in Japanese. J Epidemiol, 1992; 2 : 97-104.

Familial Dysalbuminemic Hyperthyroxinemia Associated with Multinodular Goiter and Elevated Radioiodine Uptake

Familial dysalbumenic hyperthyroxenemia characterized by elevations in serum total thyroxine (T4) and free-thyroxine index and normal free T4 and radioiodine uptake has been previously described. This syndrome is secondary to an autosomal dominant inheritance in which affected individuals are mistakenly diagnosed as thyrotoxic because of the elevation of serum levels of total T4 and free T4. The excess T4 level is caused by the presence of an abnormal serum protein that binds excess T4, thereby raising the level of total T4. The authors report the case of a patient with familial dysalbumenic hyperthyroxenemia who presented with superimposed multinodular goiter and an elevated 24-hour radioiodide uptake.

Endocrine Toxicity of Drinking Water Disinfectants. I. In Vivo Dehalogenation and Clearance of Iodinated Nutrients

Ingestion of aqueous chlorine-based disinfectants has been shown earlier to cause decreased serum thyroxine levels and increased 131-I thyroid uptake in nonhuman primates. Disinfectants also were shown to immobilize iodine on gastric mucosa and cause covalent binding of dietary iodide to gastrointestinal contents in laboratory rodents. It has been demonstrated that nutrients in the presence of chlorine oxides, under conditions simulating the alimentary tract, effectively organify I- in vitro. A logical consequence of these is that traces of iodinated organics are absorbed after ingestion of drinking water disinfectants. Since over 100 million consumers receive a daily dose of about 0.4 mM of free chlorine, the pharmacotoxicology of such modified nutrient molecules is of public health interest. Therefore, we examined the in vivo deiodination of randomly in vitro iodinated organic mixtures prepared from different nutrients. Using adult female rats, we determined the 24-hour thyroid uptake of 125-I liberated from nutrients administered by gavage, relative to simultaneously ip-injected I131-. Also, 24-hour fecal and urinary clearances of the iodinated organics as well as tissue distributions were determined. The results showed that although various iodinated nutrient classes widely differed in their in vivo fate, most were dehalogenated effectively. Thus, their iodine content was returned as inorganic I- for thyroid uptake. It was also shown that tissue (blood, liver, intestinal, adipose, and muscle) distribution of the two isotopes did not differ significantly, suggesting that at 24 hours, the originally organic iodine existed in the tissues as inorganic I-. It is likely that oral exposure to chlorine-based disinfectants did not disturb the bioavailability of I-, and any thyroid effects caused were due to mechanisms other than I- deficiency.

Thyrotoxicosis Induced Sick Sinus Syndrome: Medical Therapy May Avoid Permanent Pacing

A 65-year-old white female developed sick sinus syndrome associated with thyrotoxicosis which resolved upon achieving a euthyroid state, thus obviating the need for permanent pacemaker implantation. TSH was less than 0.1 ng/dL, and 24-hour iodine uptake was 28%. After correction of the hyperthyroid state with propylthiouracil and potassium iodine, sinoatrial pauses up to 6 seconds resolved over 10 days. A subsequent sinus node recovery time was normal and no symptoms recurred over 22 months.

Estimation of 24-Hour Thyroid Uptake of 1-131 Sodium Iodide Using a 5-Minute Uptake of Technetium-99m Pertechnetate

The authors have developed a method to estimate the 24-hour sodium iodide thyroid uptake based on a 5-minute Tc-99m pertechnetate thyroid uptake using the equation: Estimated Iodide Uptake = 17.72*In(Pertechnetate Uptake) + 30.40. This estimation has a correlation coefficient of 0.90. It is based on a data pool of 44 patients who underwent I-131 and Tc-99m studies within 2 weeks of each other from 1978-1988, with established diagnoses as follows: 12 euthyroid, 6 hyperthyroid with multinodular goiters, 15 hyperthyroid with diffuse goiters, 4 with subacute thyroiditis, and 7 unknown. The population consisted of 30 women and 14 men with a mean age of 52.0 +/- 17.5 years; this sample was screened for use of thyroid hormone, propylthiouracil, and radiographic contrast. The authors believe this estimation method is of value whenever a 24-hour iodide uptake is desired, and where speed and minimizing radiation dose are factors. This method is strongly recommended for thyroid uptake evaluation before I-131 therapy.

Studies on the T3 Suppression Test with Reference to the Thyrodial 123I Uptake in Graves' Disease: Comparison of 24-Hour and 3-Hour Uptake.

Eighty-three patients with Graves' disease had been treated with methylmercaptoimidazole (MMI). They were prescribed a maintenance dose of antithyroid drug (MMI, 5 mg/day) at the time of a T3 suppression test. The 3-hour and 24-hour thyroidal 123I uptake after T3 administration (75 micrograms/day, 2 weeks) were measured (post T3 uptake). In 38 patients whose post T3 uptake was below 35% in post T3 24-hour uptake, treatment was stopped. The T3 suppression test was then repeated 1 and 3 months later. During a one-year follow up, 26 remained well, while 12 relapsed within 6 to 12 months. We have observed a good correlation between 3-hour uptake and 24-hour uptake of 123I after T3 administration (r = 0.847, p less than 0.001). In 38 patients who showed positive T3 suppression, most patients with MMI withdrawal produced a marked overshoot of post T3 3-hour and 24-hour uptake at one month. Retrospective analysis indicated that there was no significant difference in circulating thyroid hormone levels between remission and relapse groups. The present study provides evidence that 3-hour uptake values are able to be substituted for 24-hour uptake values during a T3 suppression test. In addition, overshoot of thyroidal uptake after antithyroid drug withdrawal was observed in 3-hour values, similar to 24-hour values.

Radioiodine uptake following iodine-131 therapy for Graves' disease: an early indicator of need for retreatment.

Forty-five patients with Graves' disease were studied prospectively to determine if 24-hour I-131 uptake measurements alone or in combination with serum thyroid hormone levels at six weeks would determine the necessity for retreatment of the thyrotoxicosis. All patients with an I-131 uptake greater than 30% at six weeks required retreatment. No patient with an I-131 uptake of less than 15% required retreatment. Patients with uptakes between 15% and 30% were variable. An elevated free thyroxin index at 6 weeks is not helpful to determine which patients will remain thyrotoxic. Patients with a free thyroxin index within the normal range at six weeks can be predicted to be euthyroid by 12 weeks if their 24-hour I-131 uptake is between 15% and 30% and to be hypothyroid if their 24-hour I-131 uptake is below 15%. There was no difference between patient groups treated initially with antithyroid medication and those who were not.

Alteration of radioactive iodine uptake after treatment of hyperthyroidism with iodine 131.

To determine whether a therapeutic dose of iodine 131 affects the results of 24-hour radioactive iodine uptake (RAIU) testing, we reviewed records of hyperthyroid patients previously treated with 131I at Michigan State University and its affiliated hospitals. We identified 26 patients who had had clinical evaluation and determination of the serum thyroxine (T4) level, triiodothyronine resin uptake (T3RU), and RAIU (using 131I) within two weeks before and several months after the therapeutic dose of 131I. Before treatment, all patients had clinical hyperthyroidism, with an elevated T4 level and increased T3RU and RAIU. After treatment with 131I, eight patients (31%) had an RAIU that was discordant with their clinical and biochemical (T4 and T3RU) assessment. In six patients (23%) of the RAIU was inappropriately high, and in two patients (8%) it was inappropriately low. Since we did not identify any other factors known to interfere with the results of RAIU testing, we conclude that a therapeutic dose of 131I, may by itself increase or decrease a subsequent RAIU determination; therefore, after treatment with 131I, RAIU is not a good diagnostic index of thyroid activity.

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<h3>PATHOLOGIC QUIZ CASE 1</h3> Richard Scharf, DO; Jamie R. Stern, MD; Barry L. Wenig, MD, New Hyde Park, NY. A 53-year-old man presented with a 5 × 5-cm firm, nontender, midline neck mass inferior to the hyoid bone that moved during deglutition. The patient denied drainage from the mass hoarseness, hemoptysis, otalgia, or dysphagia. There was no change in the patient's weight, skin, hair, or bowel habits. He denied cigarette smoking or alcohol abuse. Results of a thyroid scan using technetium 99m (Fig 1) demonstrated normal thyroid tissue with a small increase in activity in the region of the mass. Results of laboratory studies disclosed the following values: 24-hour uptake of radioiodine, 0.24 (24%) (normal, 0.15 to 0.40 [15% to 40%]); triiodothyronine, 2.6 nmol/L (167 ng/dL) (normal, 1.5 to 2.9 nmol/L [100 to 190 ng/dL); thyroxine, 132 nmol/L (10.28 μg/dL) (normal, 71 to 148 nmol/L [5.5 to 11.5 μg/dL]); and thyroid-stimulating hormone, 5 mU/L (5 μU/mL) (normal, 0 to 10 mU/L [0 to 10 μU/mL]).

MR imaging in thyroid disorders: correlation of signal intensity with Graves disease activity.

Thirty-six patients with a variety of thyroid disorders and eight healthy subjects were studied with T1- and T2-weighted magnetic resonance (MR) imaging. Solid benign nodules, malignant tumors, and inflammatory conditions were not distinguishable by thyroidal MR signal intensity, but almost all patients with Graves disease had a moderate to marked diffuse increase in signal intensity at both settings. Quantitative evaluation showed that in these patients, the thyroid-muscle signal intensity contrast ratio was linearly related to both the serum thyroxine (T4) level and the 24-hour radioactive iodine uptake. In three patients treated with iodine 131, this contrast ratio rose or fell in parallel with the serum T4 level and 24-hour radioactive iodine uptake. Either parenchymal changes or increased vascularity in Graves disease, or both, could produce these findings. In patients without Graves disease, signal intensity was not correlated with serum T4 levels. These findings suggest that MR signal intensity may reflect the activity of the stimulatory process in Graves disease and may therefore be a useful measure of thyroid function in this disorder, with both diagnostic and prognostic value.

Total Bone Uptake in Management of Metastatic Carcinoma of the Prostate

The status of patients with skeletal metastases from prostatic carcinoma was determined from a quantitative uptake and retention measurement of the bone scanning radiopharmaceutical 99mtechnetium-methylene diphosphonate. Whole body counts were performed 5 minutes and 24 hours after intravenous administration of 99mtechnetium-methylene diphosphonate, and were expressed as the percentage uptake by the skeleton at 24 hours. Skeletal uptake determinations were done in 29 patients with prostatic cancer (17 with osseous metastases) who were evaluated at 3 to 6-month intervals. Group 1 consisted of patients who responded to therapy and achieved remission, group 2 included patients with relapse or progressive disease, group 3 consisted of those with metastases who were in remission for longer than 6 months and group 4 included those without evidence of any bony metastases. The baseline mean ± standard deviation 24-hour skeletal uptake values were 46.1 ± 12.0 per cent in group 1, 34.3 ± 13.9 per cent in group 2, 27.0 ± 5.9 per cent in group 3 and 28.9 ± 5.5 per cent in group 4. At 3 to 6 months the values in group 1 (responders) decreased by 18 per cent, while those in group 2 (relapse or progression) increased by 19 per cent and those in group 3 (remission) increased by 1.5 per cent.The quantitative 24-hour skeletal uptake test was performed easily, reproducible and at least as useful as concurrent chemical blood tests and subjective bone scan interpretations.

Cresyl fast violet staining method for Campylobacter like organisms.

Over a 7-year period transient hyperthyroidism was diagnosed in 35 patients seen in a consulting practice in a community hospital. The patients were followed up for an average of 15 months. Initially all of them had biochemical evidence of hyperthyroidism but a very low 24-hour uptake of radioiodine. The hyperthyroid phase was short, and there were no relapses. Seventeen patients subsequently became hypothyroid; this phase, too, was almost always transient. The clinical course of the disease in the 11 women who became hyperthyroid within 6 months after giving birth was similar to that experienced by the other patients, but of the 11 who had increased titres of antimicrosomal antibodies a significantly greater proportion (73%) showed at least transient evidence of hypothyroidism; 1 patient remained frankly hypothyroid for a year. Transient hyperthyroidism can be distinguished from Graves9 disease only if the uptake of radioiodine is measured. It is important to make this distinction, as transient hyperthyroidism can be managed safely and symptomatically with beta-blockers alone. The propensity of this disease for the postpartum period and the high proportion of patients with antithyroid antibodies suggest an autoimmune cause.