Progesterone levels and sleep-related breathing during menstrual cycles of normal women.

The respiratory stimulant effect of progesterone has been known for many years and has led to the hypothesis that this hormone protects young, premenopausal women from disordered breathing and apnea during sleep. Therefore, sleep, breathing, and gonadal hormone parameters were evaluated for 11 normal, menstruating women during times of high and low progesterone levels. No sleep or breathing parameter changed significantly with varying levels of progesterone. Although normal women show a significant change in progesterone levels across the course of the menstrual cycle, the levels achieved did not produce significant changes in breathing parameters.

Epinephrine fraction of adrenal vein blood in pheochromocytoma.

Variability in the levels of epinephrine (E) and norepinephrine (NE) in adrenal vein blood is thought to preclude their usefulness in caval sampling studies for localizing abdominal pheochromocytoma. In this study we demonstrate, in three patients, that the fraction of the total catecholamine level in the adrenal effluent represented by E (E fraction) may differentiate the normal adrenal medulla from the gland containing a pheochromocytoma. This observation is additionally supported by calculations of the E fractions, from adrenal venous E and NE reported recently, in three other patients with pheochromocytoma. Our data, combined with those from the literature, yield a mean E fraction, in adrenal vein blood, of 63.8 +/- 11.4 (SD)% for seven normal adrenal medullae, and of 28.5 +/- 4.8% for five glands bearing pheochromocytoma. The use of this parameter for lateralizing adrenal pheochromocytoma is suggested if other procedures are unable to demonstrate the tumor.

1-Deamino-8-D-arginine vasopressin and urine cyclic adenosine monophosphate excretion in diabetes insipidus.

The response to 1-deamino-8-D-arginine vasopressin (DDAVP), an intranasally administered analogue of vasopressin, was investigated in children and adults with central diabetes insipidus. To assess the action of DDAVP on the distal nephron, cyclic adenosine monophosphate (cAMP) excretion was assayed in urine collected 4 hr before and during four subsequent 4-hr periods after intranasal administration of 5 micrograms DDAVP. Maximal effects on urine volume and concentration were observed between 4 and 12 hr, coinciding with an elevated cAMP excretion in seven subjects. The pretreatment 4-hr cAMP excretion (micrograms/gm creatinine) correlated inversely with age (p less than 0.02) and surface area (p less than 0.001). Subsequent cAMP excretion after DDAVP increased inconsistently with no relationship to duration of antidiuresis, indicating that urinary cAMP is a poor index of antidiuretic hormone action on the distal nephron. We also confirmed that DDAVP intranasally induces antidiuresis in patients with diabetes insipidus over approximately 12 hr.

Myxedema and obstructive sleep apnea.

Three cases of hypersomnolence, snoring and documented sleep apnea are reported. All three patients were profoundly myxedematous, both clinically and biochemically. Polygraphic studies during sleep documented the presence of repetitive episodes of obstructive sleep apnea in all three patients. These were accompanied by arterial oxygen desaturation. After becoming euthyroid following the administration of the l-thyroxine all patients underwent a repeat evaluation in the sleep laboratory. These studies revealed nearly complete resolution of obstructive sleep apnea in all patients. In addition, several sleep parameters showed marked improvement. These data strongly suggest that the presence of profound daytime sleepiness in hypothyroid patients could be indicative of a potentially lethal complication of myxedema, obstructive sleep apnea.

Vitamin D metabolite levels in oncogenic osteomalacia.

Measurements of 1,25 (OH)2D3 and other metabolites of vitamin D in a patient with oncogenic osteomalacia confirm the selective, reversible deficiency of 1,25 (OH)2D3 in this syndrome, and indicate the rapidity of normalization (within days) of the hormone level and associated hypophosphatemia after resection of the tumor. In this patient, the tumor was an intranasal hemangiopericytoma.

Hyperparathyroidism after radiation of the head and neck: a case report and review of the literature.

A 66-year-old woman presented with hypercalcemia and a past history of external radiation to the neck. Hyperparathyroidism in this patient was caused by a parathyroid adenoma. The literature associating hyerparathyroidism with prior radiation of the head and neck was reviewed and analyzed. Current evidence supports a relationship between external radiation of the head or neck and the development of hyperparathyroidism as a late complication. Analysis of data available suggests that radiation-association hyperparathyroidsim develops after an average latent period of 38 years. Parathyroid adenoma occurred more often than did hyperplasia. Parathyroid carcinoma has not been reported in irradiated patients with hyperparathyroidsim. Neither age at radiation exposure, age at diagnosis of hyperparathyroidsim, nor interval between exposure and diagnosis was associated with a specific histologic diagnosis (adenoma or hyperplasis).

Turner's syndrome: index case after 44 years (a tribute to Dr. Henry H. Turner).

Forty-four years after Dr. Henry Turner's original observations, the index case of Turner's syndrome was re-examined. Mild hypertension and sensorineural deafness were found in addition to the classic somatic changes of gonadal dysgenesis. Buccal smear examination and chromosome analysis, previously not performed, revealed absence of chromation bodies and 45,X, respectively.