Showing papers by "Christina Wang published in 1986"

Hypothalamic hypopituitarism following cranial irradiation for nasopharyngeal carcinoma.

Abstract: Eight patients, one male and seven females, with no pre-existing hypothalamic-pituitary disease, who developed symptoms of hypopituitarism following cranial irradiation for nasopharyngeal carcinoma were studied 5 years or more after radiotherapy. All were GH deficient. Four of the patients with no GH response during insulin tolerance tests (ITT) showed increased GH in response to synthetic human growth hormone releasing factor (GRF-44). Four patients had impaired cortisol responses to ITT, and gradual but diminished cortisol responses to ovine corticotrophin releasing factor (CRF-41). There was no significant difference between mean peak increments in response to ITT and those in response to CRF-41. TSH responses to TRH were delayed in five and absent in two patients; four of these had low free T4 index. Prolactin was raised in all seven women and increased further in response to TRH. Two patients had impaired gonadotrophin responses to LHRH. None of the patients had clinical or biochemical evidence of diabetes insipidus. These data suggest that post-irradiation hypopituitarism in these patients results from radiation damage to the hypothalamus leading to varying degrees of deficiency of the hypothalamic releasing or inhibitory factors.

Fifty Cases of Primary Hyperaldosteronism in Hong Kong Chinese with a High Frequency of Periodic Paralysis. Evaluation of Techniques for Tumour Localisation

Abstract: Fifty consecutive Chinese patients with primary hyperaldosteronism were studied. All were considered to have an adrenal cortical adenoma, this being proven by surgery in 46 cases. In contrast to other reports, periodic paralysis was a presenting feature in 42 per cent of patients. Other notable symptoms were palpitations (30 per cent) and syncope (12 per cent). Vascular complications were present in 20 per cent of cases. Mean serum potassium level at presentation was 2.1 +/- 0.1 (mean +/- SEM) and sodium 145.0 +/- 0.1 mmol/l. Serum potassium was significantly lower and plasma aldosterone higher in patients with periodic paralysis. Adrenal venography in order to localise the tumour was unreliable and was misleading in two cases. Adrenal venous sampling for steroid analysis was much more helpful, despite the difficulty of obtaining right adrenal venous blood. The side of the adenoma could be predicted in 97 per cent of cases from measurements of left adrenal venous and vena caval aldosterone levels. The use of high resolution CT gave 100 per cent accuracy in all 18 patients who underwent surgery, the smallest detected tumour being 0.8 cm in diameter. Surgery corrected hypokalaemia in all cases, and 37 of the 46 patients required no further antihypertensive treatment.

Hypothalamic defects in two adult patients with septo-optic dysplasia

Abstract: Two adult patients with unilateral hypoplastic optic nerves, absent septa pellucida and hypopituitarism are described. Patient 1, aged 20, presented with diabetes insipidus due to partial vasopressin deficiency. Patients 2, aged 29, presented with focal epilepsy. Both had short stature. They showed absent growth hormone (GH) response to insulin-hypoglycaemia or glucagon, but responded to 100 micrograms growth hormone releasing factor (GRF-44) with a rise in circulating GH, suggesting a hypothalamic defect in GH release though a co-existing pituitary defect cannot be excluded. Other hypothalamic-pituitary functions were normal. These two patients probably represent the milder form of the clinical spectrum of septo-optic dysplasia which, with the extensive use of CT brain scans, will be increasingly encountered by physicians attending adult patients.