Yoichi Koizumi

Concurrent hypersecretion of aldosterone and cortisol from the adrenal cortical adenoma

Hypertension, hypokalemia, suppressed plasma renin activity and increased plasma aldosterone were found in a middle-aged woman. Following removal of the tumor in the left adrenal gland these abnormalities disappeared. Concurrently, however, the plasma cortisol level did not show normal diurnal change, although the value at 6 A.M. was within the normal range. Administration of 2 mg dexamethasone failed to depress the plasma cortisol level and urinary 17-OHCS concentrations. Postoperatively, plasma cortisol and urinary 17-OHCS were below normal. Histologic examination of the tumor indicated the presence of two types of adenoma cells; one was a large watery clear cell with rich lipid and possibly with aldosterone secretion and the other was an acidophilic cell with poor lipid and possibly with cortisol secretion. It is suggested that, in addition to oversecretion of aldosterone, the tumor autonomously secreted cortisol, although the amount of cortisol secreted was not large enough to produce typical Cushings syndrome.

Effects of Antithyroid Drug Therapy on Blood Glucose, Serum Insulin, and Insulin Binding to Red Blood Cells in Hyperthyroid Patients of Different Ages

The mechanism of glucose intolerance in thyrotoxicosis was investigated in 119 patients with Gravess disease with careful consideration of the age-related deterioration of glucose tolerance. Before and after treatment of thyrotoxicosis with antithyroid drug, changes of blood glucose (BG) and serum immunoreactive insulin (IRI) in response to 50 g oral glucose tolerance test (OGTT) and insulin binding to red blood cell (RBC) were evaluated. In control subjects, the ΣIRI/ΣBG ratio after 50-g OGTT decreased progressively with age without significant change in absolute ΣIRI value, suggesting the occurrence of age-related insulin resistance. Glucose intolerance was much more apparent in hyperthyroid patients because of age-related relative decrease of insulin secretion. Such a decrease of insulin secretion was not found in age-matched postgastrectomy patients with a similar degree of hyperglycemia, however. Maximal binding of labeled insulin and number of insulin receptors of RBC were decreased in old patients but binding affinity was unchanged. Elevation of BG was partially suppressed when serum thyroxine (T4) and triiodothyronine (T3) were reduced to moderately supernormal levels, whereas ΣBG, ΣIRI, ΣIRI/ΣBG ratio, and insulin binding to RBC were all returned to normal when normal serum thyroid hormone concentration was maintained. Our data indicate that insufficient insulin secretion and reduced insulin action at the target cell are responsible, at least in large part, for age-related glucose intolerance in hyperthyroid patients.

Endocrinological aspects of aging: Adaptation to and acceleration of aging by the endocrine system

Endocrinological functions of aging subjects deviate from those of young subjects during the aging process. There are two types of deviation expressed as: (i) an adaptation to the aging process; and (ii) an acceleration of aging. The former includes hyperparathyroidism, hyperglycemia and hyperinsulinemia. The latter includes growth hormone resistance and low‐T3 syndrome. Excess adaptation promotes the metabolic syndrome. Excess acceleration of aging easily leads subjects to mental disorder and death. In order to prevent subjects from both excess adaptation to and excess acceleration of aging, endocrinological intervention is required.

Pseudohypoparathyroidism Causing Multiple Brain Calcifications

A 51-year-old Japanese woman without any particular medical and family history presented with the sudden onset of intermittent numbness of the right hand fifth finger. Computed tomography of the head revealed extensive calcification in the bilateral globi pallidi, dentate nuclei, and subcortical white matter (Picture 1-3). However, she did not have any neurological manifestations, such as movement disorder, extrapyramidal signs and cerebellar dysfunction. Trousseau’s sign was observed without hyperventilation and it caused her intermittent numbness. Her serum calcium level was 6.1 (normal 8.7-10.3) mg/dL. Serum phosphate, magnesium, and 1, 25-(OH)2 vitamin D levels and thyroid and renal function were normal; intact-parathyroid hormone (PTH) level was 193 (normal 10-65) pg/mL. A diagnosis of pseudohypoparathyroidism was thus made. There was no calcification observed at any other sites characteristic for this disease. She had no physical characteristics typical of Albright’s hereditary osteodystrophy and she was classified as type 1b. Her serum calcium levels thereafter normalized and the symptoms disappeared following alfacalcidol treatment. Pseudo-