Clinical endocrinology
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Clinical endocrinology · Feb 1989
Case ReportsBilateral testicular tumours in congenital adrenal hyperplasia: a continuing diagnostic and therapeutic dilemma.
Bilateral testicular tumours are a rare but well described complication of congenital adrenal hyperplasia (CAH). It can be extremely difficult to distinguish histologically between Leydig cell tumours and adrenocortical rest hyperplasia which may lead in some cases to unnecessary orchidectomy in young men. A 26-year-old male in whom CAH had been diagnosed neonatally, was referred for further investigation of a craggy mass in the left testis. ⋯ Spermatogenesis returned and the patient's wife became pregnant after 6 months; she gave birth to a normal male infant. To our knowledge, this is the first time in this clinical setting that fertility has been achieved. This case highlights the need for both a functional and histological assessment of such 'tumours' in CAH prior to orchidectomy.
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Clinical endocrinology · Mar 1985
Clinical Trial Controlled Clinical TrialEffect of a single bolus of etomidate upon eight major corticosteroid hormones and plasma ACTH.
In a prospective controlled trial we investigated the effect of an induction dose of etomidate (0.26 mg/kg i.v.) on plasma ACTH, progesterone, 17 alpha OH-progesterone, 11-deoxycortisol, cortisol, cortisone, corticosterone, 11-deoxycorticosterone, and aldosterone in seven males undergoing general anaesthesia. Seven other male patients receiving thiopentone at induction (5.0 mg/kg i.v.) served as controls. Plasma ACTH concentrations rose higher in the etomidate group (346 +/- 124 vs. 117 +/- 74 pg/ml, mean +/- SEM), but the difference was not significant. ⋯ Plasma 11-deoxycortisol and 11-deoxycorticosterone concentrations were grossly elevated 210 min after etomidate (91 +/- 28 nmol/l and 7.04 +/- 0.47 nmol/l, respectively, P less than 0.01) demonstrating inhibition of 11 beta-hydroxylation of both glucocorticoid and mineralocorticoid intermediates. In contrast, no significant difference in plasma progesterone and 17 alpha-OH-progesterone levels was found between the two groups indicating that the cholesterol-side-chain cleavage enzyme is less sensitive to etomidate than 11 beta-hydroxylase. Our results suggest that after induction of anaesthesia with a single bolus of etomidate, inhibition of other enzymes in the corticosteroid-synthetic pathway (e.g. cholesterol-side-chain cleavage enzyme) is of little clinical relevance.
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Clinical endocrinology · Jan 1984
Dopaminergic control of gonadotrophin secretion in normal women and in patients with pathological hyperprolactinaemia.
The role of dopaminergic mechanisms in the control of gonadotrophin secretion in normal and hyperprolactinaemic subjects is controversial. Whilst bromocriptine, a potent dopamine agonist, has been used to restore normal gonadotrophin secretion in subjects with pathological hyperprolactinaemia (PHP), dopamine and dopamine agonists have been reported to suppress basal and stimulated gonadotrophin release. We therefore investigated the importance of dopaminergic control of gonadotrophin secretion by studying LH, FSH and PRL responses in normal and PHP subjects to central dopamine synthesis inhibition using monoiodotyrosine (MIT) and to a 4 h dopamine infusion designed to elevate peripheral plasma dopamine concentration to levels reported for pituitary portal plasma (1-6 ng/ml). ⋯ We conclude that dopamine mechanisms do not play a significant role in modulating gonadotrophin release in normal subjects. In PHP patients, PRL feedback results in increased hypothalamic dopamine activity which in turn inhibits LH release. We conclude that the inhibitory action of dopamine on PRL release restores LH secretion by removing central dopaminergic inhibition through hypothalamic feedback of PRL.
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Clinical endocrinology · Dec 1982
Comparative StudySalivary cortisol assays for assessing pituitary-adrenal reserve.
Cortisol concentrations were determined in matched samples of plasma and saliva from patients and healthy volunteers throughout the course of standard tests of pituitary and adrenal reserve. During insulin tolerance tests the percentage incremental changes in cortisol concentrations in saliva were strictly comparable with those in plasma and showed less inter-subject variance. The clinical decision taken with regard to the integrity of the pituitary-adrenal axis was the same whether plasma or salivary cortisol was measured. ⋯ Absence of the circadian rhythm in cases of hypercortisolism was seen as well in saliva as in plasma. Assays for salivary cortisol therefore provide information which is as clinically useful as that of plasma determinations. Since salivary cortisol concentrations were shown to reflect the free, biologically active fraction in plasma, salivary assay may, in selected cases, provide results of greater diagnostic significance than plasma total concentrations.
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Clinical endocrinology · Sep 1978
Glucose-induced insulin secretion in patients with parathyroid disorders.
Glucose-induced insulin secretion was studied in ten patients with primary hyperparathyroidism and two with idiopathic hypoparathyroidism both before and after treatment. In each individual, insulin secretion during an intravenous glucose tolerance test was greater when the plasma calcium was higher. No consistent change in insulin secretion with plasma calcium concentration was observed during an oral glucose tolerance test. These findings could be explained by the suggestion that insulin secretion provoked by orally administered glucose is enhanced by gut hormones which may stimulate insulin secretion by a mechanism independent of extracellular calcium.