Blood pressure response to thyrotropin-releasing hormone in euthyroid subjects.

The iv administration of TRH has been associated with side effects, such as nausea, flushing, and urinary urgency. However, few reports mention changes in blood pressure. This study defines the mean and range of the blood pressure responses in 70 euthyroid patients subjected to iv administered TRH. The mean increase was 21.0 +/- 1.4 mm Hg for systolic and 13.9 +/- 1.0 mm Hg for diastolic blood pressure; however, individual peak values increased as much as 56 and 42 mm Hg, respectively. Thus, the hemodynamic response to iv administered TRH can be quite severe in some subjects, and caution is suggested in selecting patients for testing.

Effect of long-term amiodarone therapy on thyroid hormone levels and thyroid function.

Both hyperthyroidism and hypothyroidism have been noted to occur in some patients treated with amiodarone for cardiac arrhythmias. To determine the frequency of the development of thyroidal abnormalities in patients receiving amiodarone, 45 euthyroid patients were prospectively evaluated. Serum samples were obtained for measurement of thyroxine, thyrotropin, triiodothyronine, and triiodothyronine resin uptake prior to initiation of amiodarone treatment and serially over a 12- to 27-month period during which amiodarone was administered. The patients were divided into four subgroups as follows: Group I (n = 22) had elevated thyroxine levels, Group IIA (n = 13) had normal thyroxine levels and normal thyrotropin levels, Group IIB (n = 7) had normal thyroxine levels and elevated thyrotropin levels, and Group III (n = 3) had subnormal thyroxine levels. Demographic factors (such as route of administration, cardiac diagnosis, sex of the patient, or indication for amiodarone therapy) and amiodarone levels had no significant effect on the thyroid hormone parameters. However, Group I patients were statistically older than the patients in the other groups. Linear regression analysis revealed a negative correlation for thyroxine levels and a positive correlation with thyrotropin levels with age for the whole group. The various groups were not statistically affected by duration of therapy, but a positive trend existed for increasing thyroxine levels. Although virtually all patients showed changes in their thyroid hormone levels, chemical hyperthyroidism (elevated thyroxine and triiodothyronine levels without symptoms) developed in only two patients (4 percent), and clinical hyperthyroidism (elevated thyroxine and triiodothyronine levels with symptoms) developed in no patients. Four patients (9 percent) became biochemically and clinically hypothyroid. Thus, amiodarone frequently influences thyroid hormonal parameters, but less commonly causes a change in actual thyroid function. However, hyperthyroidism and hypothyroidism do occur in a significant number of patients.

The effect of E. coli L-asparaginase on oral glucose tolerance and insulin release in man.

To study the effect of E. Coli L-asparaginase on glucose tolerance and insulin release, 6 patients with neoplastic disease were subjected to 3 hour oral glucose tolerance tests with simultaneous measurement of serum immunoreactive insulin (IRI) levels before and following the intravenous administration of 5000 I. U. L-asparaginase/day for 4 days. Five of the patients exhibited a significant deterioration in glucose tolerance; however, no change was noted in their fasting glucose and IRI levels. The deterioration in glucose tolerance was associated with a decrease in the amount of insulin secreted in the first 30 minutes after the oral glucose load. The total amount of insulin released during the 3 hour test remained unchanged. These studies suggest that L-asparaginase can cause a deterioration of glucose tolerance without accompanying fasting hyperglycaemia. This may be due, in part, to a decrease in glucose-induced insulin release during the first thirty minutes following oral glucose.

Insulin-dependent diabetes mellitus. Sudden onset following hypophysectomy in an acromegalic patient.

A euglycemic woman with acromegaly contracted conspicuous hyperglycemia two hours following transphenoidal hypophysectomy. Insulin therapy was initiated and has by necessity been continued. The development in the immediate postoperative period of blood glucose levels ranging from 300 to 500 mg/dl was totally unexpected, as the levels on the preoperative oral glucose tolerance test were normal. No explanation for this sudden development of hyperglycemia is apparent. Therefore, frequent monitoring of the blood glucose level is necessary in all acromegalic patients following hypophysectomy, even if they are euglycemic prior to surgery.